Abstrict An adjustable bed carriage for supporting a main bed frame above
a substantially planar floor. The adjustable bed carriage has one
or more first legs, each with an upper end slidably attached to
a first end of the main bed frame, and one or more second legs,
each with an upper end pivotably attached to a second end of the
main bed frame. Each first leg is paired with a second leg, and
they are pivotably connected to each other at a central pivot located
substantially at a midpoint of each. The carriage also includes
a first caster base with one or more first casters for engaging
the floor, the first leg being attached to the first caster base.
Also, the carriage has a second caster base with one or more second
casters for engaging the floor, the second leg being attached to
the second caster base.
Claims We claim:
1. An adjustable bed carriage for supporting a main bed frame above
a substantially planar floor, the adjustable bed carriage having:
at least one first leg having an upper end slidably attached to
a first end of the main bed frame; at least one second leg having
an upper end pivotably attached to a second end of the main bed
fame; each of said at least one first leg and said at least one
second leg being pivotably connected to each other at a central
pivot located substantially at a midpoint of each, to permit pivoting
movement of each of said at least one first leg and said at least
one second leg about the central pivot in opposite directions to
move the adjustable bed carriage between an extended condition and
a retracted condition; a first caster base with at least one first
caster for engaging the floor; said at least one first leg being
attached to the first caster base; a second caster base with at
least one second caster for engaging the floor; and said at least
one second leg being attached to the second caster base.
2. An adjustable bed carriage according to claim 1 in which said
at least one second caster includes: a wheel assembly having a housing
and a wheel rotatable about an axis defined by an axle subassembly
positioned in the housing; a mounting portion for mounting the wheel
assembly to the second caster base; and a directional lock for locating
the wheel assembly in at least one predetermined position relative
to said at least one second leg.
3. An adjustable bed carriage according to claim 1 in which said
at least one first caster includes: a wheel assembly having a housing
and a wheel rotatable about an axis defined by an axle subassembly
positioned in the housing; a mounting portion for mounting the wheel
assembly to the first caster base; and a brake for preventing rotation
of the wheel about the axis, the brake being adapted for braking
the wheel upon activation thereof and releasing the wheel upon deactivation.
4. An adjustable bed carriage according to claim 1 in which said
at least one second caster includes: a wheel assembly having a housing
and a wheel rotatable about an axis defined by an axle subassembly
positioned in the housing; a mounting portion for mounting the wheel
assembly to the second caster base; and a brake for preventing rotation
of the wheel about the axis, the brake being adapted for braking
the wheel upon activation thereof and releasing the wheel upon deactivation.
5. An adjustable bed carriage according to claim 1 in which said
at least one first caster includes: a wheel assembly having a housing
and a wheel rotatable about an axis defined by an axle subassembly
positioned in the housing; a mounting portion for mounting the wheel
assembly to the first caster base; and a directional lock for locating
the wheel assembly in at least one predetermined position relative
to said at least one first leg.
6. An adjustable bed carriage according to claim 1 in which each
said caster includes: a wheel assembly having a housing and a wheel
rotatable about an axis defined by an axle subassembly positioned
in the housing; a mounting portion for mounting the wheel assembly
to each said caster base respectively; and a directional lock for
locating each said wheel in at least one predetermined position
relative to each said leg respectively.
7. An adjustable bed carriage according to claim 1 in which each
said caster includes: a wheel assembly having a housing and a wheel
rotatable about an axis defined by an axle subassembly positioned
in the housing; a mounting portion for mounting the wheel assembly
to each said caster base respectively; and a brake for preventing
rotation of tho wheel about the axis, the brake being adapted for
braking the wheel upon activation thereof and releasing the wheel
upon deactivation.
8. An adjustable bed carriage according to claim 1 in which pivoting
movement of said at least one second leg results in corresponding
pivoting movement of said at least one first leg and movement of
the upper end of said at least one first leg relative to the main
bed frame to move the main bed fame relative to the plane of the
floor between a fully raised position, in which the adjustable bed
carriage is in the extended condition, and a fully lowered position,
in which the adjustable bed carriage is in the retracted condition.
9. An adjustable bed for use on a substantially planar floor, the
adjustable bed including: a main bed frame having a first end and
a second end; an adjustable bed carriage for supporting the main
bed frame, the adjustable bed carriage having: at least one first
leg having an upper end slidably attached to the first end of the
main bed frame; at least one second leg having an upper end pivotably
attached to the second end of the main bed fame; each of said at
least one first leg and said at least one second leg being pivotably
connected to each other at a central pivot located substantially
at a midpoint of each said leg, to permit pivoting movement of each
of said at least one first leg and at least one second leg about
the central pivot in opposite directions to move the adjustable
bed carriage between an extended condition and a retracted condition,
moving the main bed frame relative to the plane of the floor; a
first caster base with at least one first caster for engaging the
floor; said at least one first leg being attached to the first caster
base; a second caster base with at least one second caster for engaging
the floor; and said at least one second leg being attached to the
second caster base.
10. An adjustable bed carriage according to claim 9 in which said
at least one second caster includes: a wheel assembly having a housing
and a wheel rotatable about an axis defined by an axle subassembly
positioned in the housing; a mounting portion for mounting the wheel
assembly to the second caster base; and a directional lock for locating
the wheel assembly in at least one predetermined position relative
to said at least one second leg.
11. An adjustable bed carriage according to claim 9 in which said
at least one first caster includes: a wheel assembly having a housing
and a wheel rotatable about an axis defined by an axle subassembly
positioned in the housing; a mounting portion for mounting the wheel
assembly to said the first caster base; and a brake for preventing
rotation of the wheel about the axis, the brake being adapted for
braking the wheel upon activation thereof and releasing the wheel
upon deactivation.
12. An adjustable bed carriage according to claim 9 in which said
at least one second caster includes: a wheel assembly having a housing
and a wheel rotatable about an axis defined by an axle subassembly
positioned in the housing; a mounting portion for mounting the wheel
assembly to the second caster base; and a brake for preventing rotation
of the wheel about the axis, the brake being adapted for braking
the wheel upon activation thereof and releasing the wheel upon deactivation.
13. An adjustable bed carriage according to claim 9 in which said
at least one first caster includes: a wheel assembly having a housing
and a wheel rotatable about an axis defined by an axle subassembly
positioned in the housing; a mounting portion for mounting the wheel
assembly to the first caster base; and a directional lock for locating
the wheel assembly in at least one predetermined position relative
to said at least one first log.
14. An adjustable bed carriage according to claim 9 in which each
said caster includes: a wheel assembly having a housing and a wheel
rotatable about an axis defined by an axle subassembly positioned
in the housing; a mounting portion for mounting the wheel assembly
to each said caster base respectively; and a directional lock for
locating each said wheel in at least one predetermined position
relative to each said leg respectively.
15. An adjustable bed carriage according to claim 9 in which each
said caster includes: a wheel assembly having a housing and a wheel
rotatable about an axis defined by an axle subassembly positioned
in the housing; a mounting portion for mounting the wheel assembly
to each said caster base respectively; and a brake for preventing
rotation of the wheel about the axis, the brake being adapted for
braking the wheel upon activation thereof and releasing the wheel
upon deactivation.
16. An adjustable bed according to claim 9 in which pivoting movement
of said at least one second leg results in corresponding pivoting
movement of said at least one first leg and movement of the upper
end of said at least one first leg relative to the main bed frame
to move the main bed frame relative to the plane of the floor, between
a fully raised position, in which the adjustable bed carriage is
in the extended condition, and a fully lowered position, in which
the adjustable bed carriage is in the retracted position.
17. An adjustable bed according to claim 9 additionally including
at least one motor mounted on the main bed frame and coupled to
the adjustable bed carriage, for acting upon the adjustable bed
carriage to move the adjustable bed carriage between the extended
condition and the retracted condition.
18. An adjustable bed according to claim 17 in which the adjustable
bed carriage is positionable between the extended condition and
the reacted condition.
19. An adjustable bed according to claim 9 additionally including
at least one motor mounted on the main bed frame and coupled to
said at least one second leg, said at least one motor being adapted
to push the lower end of said at least one second leg away from
the main bed frame and to pull the lower end of said at least one
second leg toward the main bed frame.
20. An adjustable bed according to claim 9 additionally including
at least one motor mounted on the main bed frame and coupled to
said at least one first leg, said at least one motor being adapted
to push the lower end of said at least one first leg away from the
main bed frame and to pull the lower end of said at least one first
leg toward the main bed frame.
21. An adjustable bed for use on a substantially planar floor,
the adjustable bed having: a main frame for supporting a mattress,
the main frame having a first end and a second end; a scissor leg
assembly for supporting the main frame; a motor mounted on the main
frame and attached to the scissor leg assembly, for causing the
scissor leg assembly to move between an extended condition, in which
the main frame is in a fully raised position, and a retracted condition,
in which the main frame is in a filly lowered position; the scissor
leg assembly including: a first pair of legs having a proximal end
slidably attached to the main frame at the first end and a second
pair of leg having a proximal end pivotably attached to the main
frame at the second end; a first caster base mounted at a distal
end of the first pair of legs and positioned distal to the first
end of the main frame, the first caster base including at least
one first caster for engaging the floor; the first pair of legs
being attached to the first caster base; the first caster base being
disposed in a preselected position relative to the floor; a second
caster base mounted at a distal end of the second pair of legs and
positioned distal to the second end of the main frame, the second
caster base including at least one second caster for engaging the
floor; the second pair of legs being attached to the second caster
base; the first and second pairs of legs being pivotably connected
to each other at substantially coplanar central pivot points disposed
substantially midway between the proximal ends and the distal ends
of each said pairs of legs respectively, such that the scissor leg
assembly is movable between the extended condition and the retracted
condition; at least one first follower strut having an upper end
and a lower end, the lower end being pivotably attached to the first
caster base; the upper end of said at least one first follower strut
being pivotably attached to at least one of said legs in said second
pair of legs at a predetermined pivot point located between said
central pivot point and the proximal end of said second pair of
legs; and said at least one predetermined pivot point being selected
such that said at least one first follower strut maintains the first
caster base substantially in the preselected position relative to
the floor as the scissor leg assembly moves between the extended
condition and the retracted condition.
22. An adjustable bed according to claim 21 additionally including:
at least one second follower strut having an upper end and a lower
end, the lower end being pivotably mounted on said at least one
second caster base; the second caster base being disposed in a preselected
position relative to the floor; the upper end of said at least one
second follower strut being pivotably attached to at least one of
said legs in said first pair of legs at a predetermined pivot point
located between said central pivot point and the proximal end of
said second pair of legs; and said at least one predetermined pivot
point being selected such that said at least one second follower
strut maintains said at least one second caster base substantially
in the preselected position relative to the floor as the scissor
leg assembly moves between the extended condition and the retracted
condition.
23. An adjustable bed according to claim 22 in which each said
caster base includes: at least one locator element to which the
lower end of one of said follower struts is pivotably attached,
said at least one locator element being positioned relative to the
predetermined pivot point location such that said at least one follower
strut maintains said caster base substantially in the preselected
position relative to the floor as the main frame is moved between
the fully raised and the filly lowered positions.
24. An adjustable bed according to claim 21 additionally including
a lock assembly for maintaining the adjustable bed in a stationary
position, the look assembly having: a body pivotably mounted to
the first caster base; a means for urging the body to pivot upwardly;
a lock linkage pivotably mounted to the first caster base at an
upper pivot point the lock linkage being pivotable between a low
position and a high position; a release linkage pivotably mounted
to the body at at least one lower pivot point; the release linkage
and the lock linkage being pivotably attached to each other at a
middle pivot point disposed between the upper and lower pivot points;
the release linkage being pivotable about the middle pivot point
between a first position and a second position; the body being movable
between a locked position, in which the body engages the floor,
and a released position, in which the body is disengaged from the
floor; and the body being maintained in the locked position when
the lock linkage is in the low position thereof, and the body being
maintained in the released position when the release linkage is
in the second position thereof.
25. An adjustable bed for use on a floor, the adjustable bed having:
a main frame for supporting a mattress, the main frame having a
first end and a second end; a scissor leg assembly for supporting
the main frame; a motor mounted on the main frame and attached to
the scissor leg assembly, for causing the scissor leg assembly to
move between an extended condition, in which the main frame is in
a fully raised position, and a retracted condition, in which the
main frame is in a fully lowered position; the scissor leg assembly
including: a first pair of legs having a proximal end slidably attached
to the main frame at the first end and a second pair of legs having
a proximal end pivotably attached to the main frame at the second
end; the first pair of legs including at least one caster for engaging
the floor and positioned in at least one caster base mounted at
a distal end thereof positioned distal to the first end of the main
frame; said at least one caster base being disposed in a preselected
position relative to the plane of the floor when the scissor leg
assembly is in the extended condition; p2 the second pair of legs
having at least one wheel for engaging the floor and mounted at
a distal end thereof positioned distal to the second end of the
main frame; the first and second pairs of legs being pivotably connected
to each other at substantially coplanar central pivot points disposed
substantially midway between the proximal ends and the distal ends
of each said pairs of legs respectively, such that the scissor leg
assembly is movable between the extended condition and the retracted
condition; at least one follower strut having an upper end and a
lower end, the lower end being pivotably attached to said at least
one caster base; the upper end of said at least one follower strut
being pivotably attached to at least one of said legs in said second
pair of legs at a predetermined pivot point located between said
central pivot point and the proximal end of said second pair of
legs; said at least one predetermined pivot point being selected
such that said at least one follower strut maintains said at least
one caster base substantially in the preselected position relative
to the plane of the floor as the scissor leg assembly moves between
the extended condition and the retracted condition; a lock assembly
for maintaining the adjustable bed in a stationary position, the
lock assembly having: a body pivotably mounted to said at least
one caster base; a means for urging the body to pivot upwardly;
a lock linkage pivotably mounted to said at least one caster base
at an upper pivot point, the lock linkage being pivotable between
a low position and a high position; a release linkage pivotably
mounted to the body at at least one lower pivot point; the release
linkage and the lock linkage being pivotably attached to each other
at a middle pivot point disposed between the upper and lower pivot
points; the release linkage being pivotable about the middle pivot
point between a first position and a second position; the body being
movable between a locked position, in which the body engages the
floor, and a released position, in which the body is disengaged
from the floor; and the body being maintained in the locked position
when the lock linkage is in the low position thereof, and the body
being maintained in the released position when the release linkage
is in the second position thereof.
Description [0001] This application is a continuation-in-part of prior application
Ser. No. 10/692675 filed Oct. 27 2003 which claims the benefit
of Provisional Application No. 60/421077 filed Oct. 25 2002.
FIELD OF THE INVENTION
[0002] This invention relates to an adjustable bed carriage for
supporting a main bed frame.
BACKGROUND OF THE INVENTION
[0003] Known adjustable bed carriages are generally of three types.
One type of adjustable bed carriage includes leg assemblies which
are positioned at both ends of a main bed frame. An example of this
type of known adjustable bed carriage is disclosed in U.S. Pat.
No. 4023849 (Bethlen).
[0004] A second general type includes extendable linkages at both
ends of the main bed frame. For instance, such an adjustable bed
carriage is disclosed in U.S. Pat. No. 4097939 (Peck et al.).
[0005] The other well-known type of adjustable bed carriage includes
a base supported by casters, wheels or feet on which legs (or linkages),
are positioned, extending upwardly to the main bed frame. U.S. Pat.
No. 3462772 (Morrison) discloses an example of this general type
of known adjustable bed carriage.
[0006] Scissor leg assemblies are also known and can provide relative
simplicity and generally greater overall strength and stability.
However, scissor leg assemblies have not generally been used in
adjustable bed carriages, and those that have suffer from some deficiencies.
For example, in U.S. Pat. No. 5613255 (Bish et al.), an adjustable
bed carriage is disclosed in which two scissor leg assemblies support
the main bed frame. However, the Bish et al. adjustable bed carriage
is relatively complex, involving a relatively large number of components.
In particular, the two scissor leg assemblies are shown (in FIGS.
4 and 5 of Bish et al.) to include a number of slidable connections
between the scissor leg assemblies and a base and a main bed frame.
Such slidable connections should be minimized in order to reduce
manufacturing costs.
[0007] There is therefore a need for an improved adjustable bed
carriage for supporting a main bed frame.
SUMMARY OF THE INVENTION
[0008] In its broad aspect, the invention provides an adjustable
bed carriage for supporting a main bed frame above a substantially
planar floor. The adjustable bed carriage has one or more first
legs, each with an upper end slidably attached to a first end of
the main bed frame, and one or more second legs, each with an upper
end pivotably attached to a second end of the main bed frame. Each
first leg is paired with a second leg, and they are pivotably connected
to each other at a central pivot located substantially at a midpoint
of each, to permit pivoting movement of each of the first and second
legs about the central pivot in opposite directions, to move the
adjustable bed carriage between an extended condition and a retracted
condition. The carriage also includes a first caster base with one
or more first casters for engaging the floor, the first leg being
attached to the first caster base. Also, the carnage has a second
caster base with one or more second casters for engaging the floor,
the second leg being attached to the second caster base.
[0009] In another aspect, the second caster includes a wheel assembly
having a housing and a wheel rotatable about an axis defined by
an axle subassembly positioned in the housing, a mounting portion
for mounting the wheel assembly to the second caster base, and a
directional lock for locating the wheel assembly in at least one
predetermined position relative to said at last one second leg.
[0010] In another aspect, the first caster includes a wheel assembly
having a housing an a wheel rotatable about an axis defined by an
axle subassembly positioned in the housing, a mounting portion for
mounting the wheel assembly to the first caster base, and a brake
for preventing rotation of the wheel about the axis, the brake being
adapted for braking the wheel upon activation thereof and releasing
the wheel upon deactivation.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The invention will be better understood with reference to
the drawings, in which:
[0012] FIG. 1 is an isometric view of a preferred embodiment of
an adjustable bed carriage of the invention as well as a main bed
frame positioned thereon, the adjustable bed carriage being shown
in an extended condition;
[0013] FIG. 2 is an isometric view of the back and bottom of the
adjustable bed carriage of FIG. 1 and of the main bed frame;
[0014] FIG. 3 is a side view of a right side of the adjustable
bed carriage of FIG. 1 and of the main bed frame;
[0015] FIG. 4 is a side view of a left side of the adjustable bed
carriage of FIG. 1 and of the main bed fame,
[0016] FIG. 5 is a side view of the right side of the adjustable
bed carriage of FIG. 1 with the main bed frame positioned thereon,
and showing the adjustable bed carriage in a retracted condition;
[0017] FIG. 6 is a side view of the left side of the adjustable
bed carriage of FIG. 1 and of the main bed frame in the retracted
condition;
[0018] FIG. 7 is a side view of the front side of the adjustable
bed carriage of FIG. 1 in the extended condition and of the main
bed frame;
[0019] FIG. 8 is a side view of the rear side of the adjustable
bed carriage of FIG. 1 in the extended condition and of the main
bed frame;
[0020] FIG. 9A is a top view of the adjustable bed carriage of
FIG. 1 in the extended condition, as well as the main bed frame;
[0021] FIG. 9B is a section view of the adjustable bed carriage
of FIG. 9A and the main bed frame, taken along line A-A in FIG.
9A;
[0022] FIG. 10 is a bottom view of the adjustable bed carriage
of FIG. 1 in the extended condition and of the main bed frame;
[0023] FIG. 11A is a top view of the adjustable bed carriage of
FIG. 1 in the retracted condition and the main bed frame, drawn
at a larger scale;
[0024] FIG. 11B is a section view of the adjustable bed carriage
of FIG. 11A and the main bed fame taken along line B-B in FIG. 11A;
[0025] FIG. 12A is a side view of the adjustable bed carriage of
FIG. 1 in the extended condition and the main bed frame;
[0026] FIG. 12B is a side view of a caster base included in the
adjustable bed carriage of FIG. 12A, drawn at a larger scale;
[0027] FIG. 13A is a side view of the adjustable bed carriage of
FIG. 12A and the main bed frame, showing the adjustable bed carriage
in a first intermediate condition, drawn at a smaller scale;
[0028] FIG. 13B is a side view of the caster base included in the
adjustable bed carriage of FIG. 13A, drawn at a larger scale;
[0029] FIG. 14A is a side view of the adjustable bed carriage of
FIG. 12A and the main bed frame, with the adjustable bed carriage
in a second intermediate condition, drawn at a smaller scale;
[0030] FIG. 14B is a side view of the caster base included in the
adjustable bed carriage of FIG. 14A, drawn at a larger scale;
[0031] FIG. 15A is a side view of the adjustable bed carriage of
FIG. 12A and the main bed frame, with the adjustable bed carriage
in the retracted condition, drawn at a smaller scale;
[0032] FIG. 15B is a side view of the caster base included in the
adjustable bed carriage of FIG. 15A, drawn at a larger scale;
[0033] FIG. 16A is a bottom view of an alternative embodiment of
the adjustable bed, drawn at a smaller scale;
[0034] FIG. 16B is a section view of the adjustable bed of FIG.
16A, taken along line C-C in FIG. 16A;
[0035] FIG. 17 is a side view of an alternative embodiment of the
adjustable bed showing the adjustable bed carriage in the retracted
condition;
[0036] FIG. 18 is a side view of another alternative embodiment
of the adjustable bed showing the adjustable bed carriage in the
retracted condition;
[0037] FIG. 19 is an isometric view of another alternative embodiment
of an adjustable bed of the invention including an actuator assembly
positioned at a front end of the adjustable bed, the adjustable
bed carriage thereof being shown in an intermediate condition, drawn
at a smaller scale;
[0038] FIG. 20 is an isometric view of the adjustable bed of FIG.
19 showing the adjustable bed carriage in a retracted condition;
[0039] FIG. 21A is an isometric view of the front end of the adjustable
bed of FIG. 19 showing the adjustable bed carriage in the intermediate
condition, drawn at a larger scale;
[0040] FIG. 21B is an isometric view of the front end of the adjustable
bed of FIG. 20 showing the adjustable bed carriage in the retracted
condition;
[0041] FIG. 21C is an isometric view of the front end of the adjustable
bed of FIG. 20 showing the adjustable bed carriage in the retracted
condition showing a release mechanism in a released position;
[0042] FIG. 21D is a partial isometric view of the actuator assembly
and part of the adjustable bed showing the release mechanism in
the released position in dotted outline;
[0043] FIG. 21E is a top view of the actuator assembly of FIG.
21D, showing the release mechanism in unreleased and released positions;
[0044] FIG. 21F is a front view of the actuator assembly of FIG.
21D, showing the release mechanism in unreleased and released positions;
[0045] FIG. 22 is a side view of the adjustable bed of FIG. 19
drawn at a smaller scale;
[0046] FIG. 23 is an elevation view of the front end of the adjustable
bed of FIG. 22;
[0047] FIG. 24 is a bottom view of the adjustable bed of FIG. 22;
[0048] FIG. 25 is an isometric view of an alternative embodiment
of an adjustable bed carriage of the invention with a main bed frame
positioned thereon, the adjustable bed carriage having casters at
its rear side with directional locks mounted thereon in a disengaged
state, the adjustable bed carriage being shown in the extended condition;
[0049] FIG. 25A is an isometric view of a caster shown in FIG.
25 drawn at a larger scale;
[0050] FIG. 25B is another isometric view of the adjustable bed
of FIG. 25 drawn at a smaller scale;
[0051] FIG. 25C is an isometric view of a caster shown in FIG.
25B, drawn at a larger scale;
[0052] FIG. 26 is an isometric view of the adjustable bed carriage
of FIG. 25 and of the main bed frame with the directional locks
in an engaged state, drawn at a smaller scale;
[0053] FIG. 26A is an isometric view of a caster shown in FIG.
26 drawn at a larger scale;
[0054] FIG. 27 is a side view of a right side of the adjustable
bed carriage of FIG. 25 and of the main bed frame with the directional
locks in the disengaged state, drawn at a smaller scale;
[0055] FIG. 27A is a side view of a front side of the adjustable
bed carriage of FIG. 27 drawn at a larger scale;
[0056] FIG. 27B is a cross-section of the adjustable bed of FIG.
27 taken along line 27B-27B in FIG. 27A, drawn at a smaller scale;
[0057] FIG. 28 is a side view of the right side of the adjustable
bed carriage of FIG. 25 and the main bed frame with the directional
locks in the engaged state;
[0058] FIG. 29 is an isometric view of the adjustable bed carriage
of FIG. 25 and of the main bed frame with the directional locks
in the disengaged state, the adjustable bed carriage being shown
in the retracted condition;
[0059] FIG. 30 is an isometric view of the adjustable bed carriage
of FIG. 29 with the directional locks in the engaged state;
[0060] FIG. 31 is a side view of the right side of the adjustable
bed carriage of FIG. 29 and of the main bed frame with the directional
locks in the disengaged state;
[0061] FIG. 32 is a side view of the right side of the adjustable
bed carriage of FIG. 30 and of the main bed frame with the directional
locks in the engaged state;
[0062] FIG. 33 is a side view of the rear side of the adjustable
bed carriage of FIG. 30 and of the main bed frame with the directional
locks in the engaged state, drawn at a larger scale;
[0063] FIG. 34 is a side view of the right side of another alternative
embodiment of the adjustable bed carriage of the invention and of
the main bed frame including a lock assembly, the lock assembly
being in a locked position, the adjustable bed carriage being shown
in the extended condition, drawn at a smaller scale;
[0064] FIG. 35 is a side view of a front side of the adjustable
bed carriage of FIG. 34 and of the main bed frame, drawn at a larger
scale;
[0065] FIG. 35A is a cross-section of the lock assembly in the
locked position taken along line 35A-35A in FIG. 35 drawn at a
larger scale;
[0066] FIG. 36 is an isometric view of the adjustable bed carriage
of FIG. 34 and of the main bed frame, drawn at a smaller scale;
[0067] FIG. 37 is a side view of the right side of the adjustable
bed carriage of FIG. 34 and of the main bed frame in which the lock
assembly is in a released position, the adjustable bed carriage
being shown in the extended condition;
[0068] FIG. 38 is a side view of a front side of the adjustable
bed carriage of FIG. 37 and of the main bed frame, drawn at a larger
scale;
[0069] FIG. 38A is a cross-section of the lock assembly in the
released position taken along line 38A-38A in FIG. 38 drawn at
a larger scale,
[0070] FIG. 39 is an isometric view of the adjustable bed carriage
of FIG. 37 and of the main bed frame, drawn at a smaller scale;
[0071] FIG. 40 is a side view of the right side of the adjustable
bed carriage of FIG. 34 and of the main bed frame with the lock
assembly in the locked position, the adjustable bed carriage being
shown in the retracted condition; and
[0072] FIG. 41 is a side view of the right side of the adjustable
bed carriage of FIG. 37 and of the main bed frame with the lock
assembly in the unlocked position, the adjustable bed carriage being
shown in the retracted condition.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)
[0073] Reference is first made to FIGS. 1-8 9A, 9B and 10 to describe
a preferred embodiment of an adjustable bed carriage indicated generally
by the numeral 30 in accordance with the invention. The adjustable
bed carriage 30 is for supporting a main bed frame 32 above a substantially
planar floor 34. In the preferred embodiment, the adjustable bed
carriage 30 has first legs 40 41 with upper ends 4243 respectively.
Each upper end 42 43 is slidably attached to a first end 44 of
the main bed frame 32 as will be described. As can be seen in FIGS.
1 and 2 the adjustable bed carriage 30 also includes second legs
46 47 with upper ends 48 49 respectively, and each upper end 48
49 is pivotably attached at a second end 50 of the main bed frame
32. In addition, each of the first legs 40 41 and the second legs
46 47 are pivotably connected respectively at central pivots 52
53 located substantially at the midpoints of the legs 40 41 and
46 47. The connections of the legs 40 41 and 46 47 at the central
pivots 52 53 permit pivoting movement of the legs 40 41 and 46
47 respectively about the central pivots 52 53 in opposite directions,
as will be described. The pivoting movement of the legs 40 41 and
46 47 about the central pivots 52 53 respectively moves the adjustable
bed carriage 30 between an extended condition (FIGS. 1-4 7 8
9A, 9B and 10) and a retracted condition (FIGS. 5 6).
[0074] In the preferred embodiment, pivoting movement of the legs
46 47 results in a corresponding pivoting movement of the legs
40 41 to move the adjustable bed carriage between the extended
condition and the retracted condition, so that the main bed frame
32 is thereby moved between a fully raised position (FIGS. 14 7
8) in which the adjustable bed carriage 30 is in the extended condition
and a fully lowered position (FIGS. 5 6), in which the adjustable
bed carriage 30 is in the retracted condition. For example, as shown
in FIG. 3 pivoting movement of the leg 46 in the direction indicated
by arrow "A" would result in pivoting movement of the
leg 40 in the direction of arrow "B". Also, the pivoting
movement of the second leg 46 results in sliding movement of the
upper end of the first leg 40 in the direction of arrow "X"
in FIG. 3.
[0075] As can be seen in FIGS. 1-8 the first legs 40 41 preferably
include a first leg base 54 and the second legs 46 47 preferably
include one or more second leg bases 56. In the preferred embodiment,
the first leg base 54 includes one or more casters 58 and the second
leg base 56 includes one or more wheels 60. It will be appreciated
by those skilled in the art, however, that various devices may be
included in the first leg base 54 and the second leg base 56 for
engaging the floor 34. For example, each of the first leg base 54
and the second leg base 56 may include one or more casters, one
or more wheels, or one or more feet for engaging the floor 34.
[0076] A preferred embodiment of an adjustable bed 64 of the invention
includes the main bed frame 32 and the adjustable bed carriage 30
for supporting the main bed frame 32 on a substantially planar floor
34. Preferably, the adjustable bed 64 includes a motor 66 mounted
on the main bed frame 32 and coupled to the adjustable bed carriage
30 for positioning the adjustable bed carriage 30. Although various
types of motors could be used, the preferred motor 66 is a linear
screw drive motor powered by electricity, as is known in the art.
As shown in FIG. 9B, the motor 66 is preferably pivotably mounted
on the main bed frame 32 and pivotably mounted on the second leg
46. In the preferred embodiment, the second legs 46 47 each include
a downwardly depending flange 68 in which a distal end 70 of the
motor 66 is mounted, as will be described. When the adjustable bed
carriage 30 is to be moved from the extended condition (FIG. 9B)
(or from an intermediate position) to or towards the retracted condition,
a movable portion 72 is retracted into a motor body 74 in a controlled
manner, in the direction shown by arrow "C" in FIG. 9B.
When the adjustable bed carriage 30 is to be moved from the retracted
condition (FIG. 11B) (or from an intermediate position) to or towards
the extended condition, the movable portion 72 is pushed outwardly
from the motor body 74 in the direction of arrow "D" in
FIG. 11B.
[0077] In the preferred embodiment, the adjustable bed 64 includes
a linkage assembly (also referred to as a scissor leg assembly)
76 which includes the adjustable bed carriage 30 with follower struts
78 79 (FIGS. 1-4), as will be described. As can be seen in FIGS.
1-4 the first legs 40 41 include a caster base 80 positioned distal
to the first end 44 of the main bed frame 32. The caster base 80
includes one or more casters 58 for engaging the floor 34.
[0078] Preferably, the caster base 80 is disposed in a preselected
position relative to a plane 36 of the floor 34 when the linkage
assembly is in the extended condition, as shown in FIGS. 12A, 12B.
The follower struts 78 79 each have respective upper ends 81 82
and lower ends 83 84. As can be seen in FIGS. 1 2 and 9B, in the
preferred embodiment, the lower ends 83 84 are pivotably attached
to the caster base 80. The upper ends 81 82 of the follower struts
78 79 are pivotably attached to the second legs 46 47 respectively
(FIG. 9B). This pivotable attachment is at predetermined pivot points
86 87 on the second legs 46 47 above the central pivots 52 53.
The predetermined pivot points 86 87 are selected so that the follower
struts 78 79 can act on the caster base 80 to maintain the caster
base 80 substantially in the preselected position relative to the
plane 36 of the floor 34 as the linkage assembly 76 moves between
the extended and retracted conditions.
[0079] As can be seen in FIGS. 12A, 12B, 13A, 13B, 14A, 14B, 15A,
and 15B, in the preferred embodiment, the follower struts 78 79
only maintain the caster base 80 in substantially the preselected
position relative to the plane 36. Generally, for example, a top
surface 88 which is substantially planar is approximately horizontal
in FIG. 12A. However, the top surface 88 may be gradually inclined,
up to approximately 3-5.degree. from the horizontal (FIGS. 13B,
14B, 15B), as the linkage assembly is moved to the retracted position.
[0080] The follower struts 78 79 form a "modified" parallelogram
with the legs 40 41 and portions of the legs 46 47 i.e., they
preferably do not form a perfect parallelogram. The location of
the follower struts does not provide perfect alignment, as a perfect
parallelogram would, but is optimized to provide the best alignment
possible. As the bed is raised, the angle changes above and below
horizontal so that the bed has a level surface at the highest and
lowest positions while maintaining a substantially level surface
through the range of motion from high to low.
[0081] In the preferred embodiment, the caster base 80 includes
one or more locator elements 89 90 to which the lower ends 83
84 of the follower struts 78 79 are pivotably attached. Each of
the locator elements 89 90 is positioned so as to enable the follower
struts 78 79 to maintain the caster base 80 in substantially the
preselected position relative to the plane 36 of the floor 34.
[0082] Preferably, main bed frame 32 defines a footprint periphery
90 circumscribing the perimeter of the main bed frame 32 (FIGS.
9A, 10 11A). In addition, the caster base 80 includes one or more
mounting brackets 94 positioned, at least in part, adjacent to footprint
periphery 92. Due to the positioning of the mounting brackets 94
caster locks (i.e., brake activator/deactivators) on the casters
58 are readily accessible by an operator (not shown), even when
the adjustable bed carriage 30 is in the retracted condition, as
shown in FIG. 11A.
[0083] In use, the motor 66 is activated by a switch or other control
means (not shown), as is known in the art, if movement of the linkage
assembly 76 between the extended condition and the retracted condition,
and consequent movement of the main bed frame 32 relative to the
plane 36 of the floor 34 is desired. For example, referring to
FIGS. 12A, 13A, 14A, and 15A, to move the linkage assembly 76 from
the extended condition (FIG. 12A) to the retracted condition (FIG.
51A), the movable portion 72 is retracted into the motor body 74.
Retracting of the movable portion 72 is controlled by an electric
motor in the motor body 74 thereby ensuring that the retracting
is at a desired rate (i.e., controlled by an operator (not shown)).
Also, as will be appreciated by those skilled in the art, the retraction
could be stopped, if the operator wishes to have the linkage assembly
remain at any position intermediate between the extended and retracted
conditions. The motor 66 holds the adjustable bed carriage 30 in
the intermediate position.
[0084] Preferably, and as shown in FIG. 9B, the motor 66 is pivotably
mounted to a flange 96 which is secured to the main bed frame 32.
The flange 96 is positioned so as to locate an upper end 97 of the
motor 66 as high (in relation to the plane 36 of the floor 34) as
is feasible. Also, the flange 96 is positioned as low (in relation
to the plane 36 of the floor 34) as is feasible. The result is that
the initial raising force required to raise the linkage assembly
from the retracted condition (FIGS. 11B, 15B) is relatively low.
[0085] It will be appreciated by those skilled in the art that
the main bed frame 32 can comprise a chassis portion 98 and deck
portions 100 mounted on the chassis portion 98 (FIG. 2). The main
deck portions 100 (which would support a mattress (not shown) when
in use) are positionable in a variety of positions relative to the
chassis portion 98 as is known in the art For example, the deck
portions 100 are positionable so as to allow adjustable head and
foot elevation, so that the patient can be positioned as necessary.
Preferably, motors 102 are used to position deck portions 100 accordingly,
as is known in the art.
[0086] Preferably, the legs 40 41 and 46 47 are configured so
as to provide maximum clearance between the floor 34 and the adjustable
bed carriage 30 through a middle portion of the adjustable bed carriage
30 when in the retracted condition (FIGS. 5 6). As shown in FIGS.
5 and 6 because the legs 40 41 and 46 47 each include lower ends
which are bent relative to the substantially straight elongate other
portions of the legs 40 41 46 47 such clearance is provided
in the middle portion of the adjustable bed carriage 30 when the
adjustable bed carriage is in the retracted condition. Preferably,
the bent portion is aligned at a significant angle (e.g., up to
approximately 11.5.degree.) from the axis of the main portions of
each leg. Due to the clearance, lift devices, movable tables and
other devices for use by or with a patient (not shown) which require
clearance under the adjustable bed carriage 30 for their operation
can be used, when the adjustable bed carriage 30 is at any height.
[0087] The adjustable bed carriage 30 has the advantage of including
slidable connections only where the first legs 40 41 are connected
to the main bed frame 32. The second legs 46 47 are only pivotably
connected to the main bed frame 32 rather than also being slidably
connected. The cost of manufacturing the adjustable bed carriage
30 is thereby significantly reduced, and its operation is much simpler,
and therefore more reliable.
[0088] Additional embodiments of the invention are shown in FIGS.
16A, 16B, 17-20 21A-21F, and 22-45. In FIGS. 16A, 16B, 17-20 21A-21F,
and 22-45 elements are numbered so as to correspond to like elements
shown in FIGS. 1 to 15B inclusive.
[0089] In another embodiment shown in FIGS. 16A and 16B, an adjustable
bed 164 has an adjustable bed carriage 130 in which the first legs
140 141 are pivotably connected to the main bed frame 132 at a
first end 144 and the second legs 146 147 are slidably connected
to the main bed frame 132 at a second end 150. As can be seen in
FIG. 16b, the motor 66 is preferably mounted on the main bed frame
132 and pivotably connected to the adjustable bed carriage 130.
More particularly, the motor 66 is preferably pivotably connected
to the second legs 46 47 at a point below the central pivots.
[0090] In an alternative embodiment, shown in FIG. 17 an adjustable
bed carriage 230 includes a first leg base 254 including one or
more foot elements 262 for engaging the floor 34. As can be seen
in FIG. 17 the adjustable bed carriage 230 additionally includes
a second leg base 256 including wheels 260.
[0091] In another alternative embodiment, an adjustable bed 364
includes one or more casters 363 mounted on the main bed frame 332.
As shown in FIG. 18 the casters 63 are mounted so that, when the
adjustable bed carriage 330 is in the retracted condition, the casters
363 engage the floor 34. Accordingly, the adjustable bed 364 can
be moved on the casters 363 when the adjustable bed carriage 330
is in the retracted condition.
[0092] In another alternative embodiment, an adjustable bed 464
(shown in FIGS. 19 20 21A-F, and 22-24) includes a lock actuator
assembly 404. Preferably, the adjustable bed 464 includes a main
bed frame 432 supported by an adjustable bed carriage 430 which
includes one or more casters 458. It is preferred that, as is known
in the art, casters 458 on the adjustable bed 464 include caster
locks (or brakes) (not shown). For example, a Tente-Rollen model
2946 UAP 100 R26-28S45 includes a caster lock or brake which, when
activated, prevents rotation of a caster wheel about a caster wheel
axis and also prevents a caster housing (in which the caster wheel
is mounted) from pivoting about a caster stem. Other locking means
can be used instead of caster locks.
[0093] Preferably, the lock actuator assembly 404 includes a lock
bar 406 secured in two connectors 408 one located at each end 410
of the lock bar 406 (FIGS. 19 21A, 21B). The connectors 408 are
in turn each secured to activators 412 respectively. The lock bar
406 is movable between an activated position (FIG. 20), in which
the connectors 408 cause the activators 412 to activate the caster
locks, and a deactivated position (FIG. 19), in which the activators
412 are maintained in a position which does not result in activation
of the caster locks. Movement of the lock bar 406 from the deactivated
position to the activated position results in rotation of the activators
412. This in turn causes the caster locks to lock. Movement of the
lock bar 406 from the activated position to the deactivated position
causes rotation of the activators in the other directions, so that
the caster locks are thereby unlocked.
[0094] Preferably, an actuator 414 is mounted on the main bed frame
432 for engaging the lock bar 406 when the main bed frame 432 is
moved downwardly to an engagement position (FIG. 20). The lock bar
406 is normally in the deactivated position. It is preferred that
the engagement position be at a height which is close (i.e., a relatively
small distance above) to the main bed frame's fully lowered position.
Upon the main bed frame 432 being lowered to the engagement position,
the actuator 414 engages the lock bar 406 urging the lock bar 406
to move from the deactivated position (FIG. 19) to the activated
position (FIG. 20). The caster lock is thereby activated.
[0095] The actuator assembly 404 also includes a release plate
416 which is engageable with the actuator 414. As can be seen in
FIGS. 21C, 21D, 21E, and 21F, the release plate 416 is attached
to the frame 432 by a pin 418 about which the release plate 416
is pivotable. The release plate includes a bevelled edge 420 which
is positioned adjacent to the actuator 414. As can be seen in FIG.
21F, the actuator 414 is also attached to the main bed frame 432
by an actuator pin 422 about which the actuator is also pivotable.
[0096] Preferably, the bevelled edge 420 forms a cam surface so
that, when the release plate 416 is pivoted about the pin 418 the
bevelled edge 420 in turn engages the actuator 414 causing the
actuator 414 to move, as follows. As can be seen in FIG. 21E, movement
of the release plate 416 from an unreleased position (designated
as "U" in FIG. 21E) to a released position (designated
as "R" in FIG. 21E) causes the edge 420 to be pushed against
the actuator 414. This in turn causes the actuator 414 to pivot
about the actuator pin 422 resulting in the disengagement of the
actuator 414 from the lock bar 406. In pivoting about the actuator
pin 422 the actuator 414 moves from the engaged position (shown
as "E" in FIG. 21F) to the disengaged position (shown
as "D" in FIG. 21F).
[0097] The lock bar 406 is intended to be kept in the locked position
during use. The unlocked position is only required when moving the
bed, with or without the patient If casters are not locked, problems
can result when the patient is trying to enter or exit the bed with
no assistance. The automatic activation of a locking mechanism helps
solve the problem of accidentally leaving the bed in the unlocked
position, where the patient may be vulnerable to unexpected movement
of the bed. In practice, the bed is typically lowered to its lowest
height for sleeping, or when no treatment is required.
[0098] Another embodiment of an adjustable bed carriage 530 of
the invention is shown in FIGS. 25-33. The adjustable bed carriage
530 which is for supporting a main bed frame 532 above a substantially
planar floor 34 (FIG. 27), has one or more first legs 540 541
each with an upper end 542 543 FIG. 25B) respectively which is
slidably (and pivotably) attached to a first end 544 of the main
bed frame 532 as will be described. As can be seen in FIG. 25
the adjustable bed carriage 530 also includes second legs 546 547
with upper ends 548 549 respectively, and each upper end 548 549
is pivotably attached at a second end 550 of the main bed frame
532. Also, each of the first legs 540. 541 and the second legs 546
547 are pivotably connected respectively at central pivots 552 located
substantially at the midpoints of the legs 540 541 and 546 547.
The connections of the legs 540 541 and 546 547 at the central
pivots 552 permit pivoting movement of the legs 540 541 and 546
547 respectively about the central pivots 552 in opposite directions,
as will be described. The pivoting movement of the legs 540 541
and 546 547 about the central pivots 552 results in movement of
the adjustable bed carriage 530 between an extended condition (shown
in FIGS. 25 25B, 26 27 27A, and 27B-28) and a retracted condition
(shown in FIGS. 29-33). In the preferred embodiment, the first legs
540 541 are pivotably attached to a first caster base 580 which
includes one or more first casters 515. Also, the second legs 546
547 are pivotably attached to a second caster base 539 which includes
one or more second casters 517 for engaging the floor 34. The first
legs 540 541 are attached to the first caster base 580 at pivot
points 554 (FIG. 27B), and the second legs 546 547 are attached
to the second caster base at pivot points 555 (FIG. 27B). As shown
in FIG. 25D, crossbars 562 564 join the first legs 540 541 and
the second legs 546 547 respectively, to strengthen the adjustable
bed carriage 530.
[0099] As can be seen in FIGS. 25A and 26A, each second caster
517 includes a wheel assembly 519 having a housing 521 and a wheel
523 rotatable about an axis 524 defined by an axle subassembly 525
positioned in the housing 521. Each second caster 517 additionally
includes a mounting portion 526 for mounting the wheel assembly
519 to the second legs 546 547 respectively.
[0100] In addition, each of the second casters 517 preferably includes
a directional lock 527 for locating the wheel assembly 519 in one
or more predetermined positions relative to the second legs 546
547. The directional lock 527 is described in the Applicant's application
Ser. No. 10/406253 filed on Apr. 4 2003 the complete specification
of which is hereby incorporated by reference. Preferably, in the
predetermined position, the axis 524 in each second caster 517 is
substantially orthogonal to the second legs 546 547.
[0101] In the preferred embodiment, each first caster 515 includes
a wheel assembly 528 having a housing 529 and a wheel 523 rotatable
about an axis 524 defined by an axle subassembly 525 positioned
in the housing 529 (FIG. 25C). Each first caster 515 additionally
includes a mounting portion 531 for mounting the wheel assembly
528 to the second legs 546 547 respectively.
[0102] In addition, each of the first casters 515 preferably includes
a brake (or caster lock, described above) 533 for preventing rotation
of the wheel 523 about the axis 524. The brake 533 is adapted for
braking the wheel upon activation thereof and releasing the wheel
523 upon deactivation, as is known in the art. Preferably, the brake
533 is activated by the operator depressing an activator 534 (thereby
moving the activator 534 to an engaged position) and subsequently
deactivated by pressing again on the activator 534 (thereby moving
the activator 534 to a released position), as is known in the
[0103] It will be appreciated by those skilled in the art that
the mounting portion can have various forms. For example, as shown
in FIG. 25A, the mounting portion is a bolt (not shown) secured
by a nut. However, any suitable type of mounting portion can be
used, as is known in the art.
[0104] As can be seen in FIG. 25B, the first caster base 580 preferably
includes a crossbar 611 on which mounting brackets 94 are positioned.
In the preferred embodiment, the first casters 515 are mounted to
ends 612 of each of the mounting brackets 94 which are located distal
to the crossbar 611.
[0105] The first caster base 580 additionally includes the locator
elements 589 590 and each locator element 589 590 is spaced inwardly
from the mounting brackets 94 respectively so that the first follower
struts 578 579 are positioned to be spaced apart from the first
legs 540. 541 respectively and can pivot without interference from,
or interfering with, the first legs 540 541 and the second legs
546 547 (FIG. 27A). The first caster base 580 also includes depending
flanges 613 which preferably extend downwardly from the crossbar
611. The first legs 540 541 are pivotably mounted to the depending
flanges 613 at pivot points 554 (FIG. 27B). In the preferred embodiment,
the lower ends 583 of the first follower struts 578 579 are pivotably
attached to the locator elements 589 590. Each of the locator elements
589 590 is positioned so as to enable the follower struts 578
579 to maintain the first caster base 580 in substantially the preselected
position relative to the plane 36 of the floor 34 to the extent
feasible. Although any suitable materials could be used, in the
preferred embodiment, the first caster base 580 is made of tubular
steel and steel plate.
[0106] As can be seen in FIGS. 25 25A, and 25B, the second caster
base includes a crossbar 621. The crossbar 621 has elevated portions
622 at each of its ends. Preferably, the second casters 517 are
mounted to mounting brackets 594 which are attached to the crossbar
621 at the elevated portions 622 thereof. The mounting brackets
594 include ends 623 located distal to the crossbar 611 and the
casters 517 are mounted to the ends 623 of the mounting brackets
594.
[0107] The second caster base 539 additionally includes locator
elements 689 690. Each locator element 689 690 is spaced inwardly
from the mounting brackets 594 respectively so that the second follower
struts 535 537 are positioned to be spaced apart from the second
legs 546 547 and the first legs 540 541 (FIG. 26). The second
caster base 539 also includes depending flanges 624 which preferably
extend downwardly from the crossbar 621 (FIG. 25B). The second legs
546 547 are pivotably mounted to the depending flanges 624 at pivot
points 555 (FIG. 27B). Also, the lower ends 584 of the second follower
struts 535 537 are pivotably attached to the locator elements 689
690. Each of the locator elements 689 690 is positioned so as to
enable the follower strut 535 537 to maintain the second caster
base 539 in substantially the preselected position relative to the
plane 36 of the floor 34. Although any suitable materials could
be used, in the preferred embodiment, the second caster base 539
is made of tubular steel and steel plate.
[0108] As can be seen in FIGS. 25-33 the first end 544 of the
main bed frame 532 is preferably used as the head end of a bed including
the adjustable bed carriage 530 i.e., the end of the main bed frame
532 at which the patient's head would customarily be positioned
in use. Also, the second end 550 is preferably used as the foot
end of the bed. However, it will be appreciated by those skilled
in the art that the first end 544 could be used as the foot end,
and the second end 550 could be used as the head end of the bed.
[0109] Accordingly, in an alternative embodiment of the adjustable
bed carriage 530 each second caster 517 includes the brake 533.
Also, each first caster 515 includes the directional lock 527.
[0110] In yet another alternative embodiment, each of the first
and the second casters 515 517 includes the brake 533. Alternatively,
each of the first and second casters 515 517 includes the directional
lock 527.
[0111] Alternatively, the second casters 517 can have neither the
brake 533 nor the directional lock 527. Similarly, the first casters
515 can have neither the brake 533 nor the directional lock 527.
In each case, however, a brake device should preferably be provided
with the bed.
[0112] A preferred embodiment of an adjustable bed 564 of the invention
include the main bed frame 532 and the adjustable bed carriage 530
for supporting the main bed frame 532 on the substantially planar
floor 34. Preferably, the adjustable bed 564 includes a motor 566
mounted on the main bed frame 532 and coupled to the adjustable
bed carriage 530 for positioning the adjustable bed carriage 530.
Although various types of motors could be used, the preferred motor
566 is a linear screw drive motor powered by electricity, as is
known in the art. As shown in FIG. 27 the motor 566 is preferably
pivotably mounted on the main bed frame 532 and pivotably mounted
on the second legs 546 547. In the preferred embodiment, a downwardly
depending flange 568 in which a distal end 570 of the motor 566
is pivotably mounted (directly or indirectly) is centrally positioned
on the crossbar 564 (FIGS. 25 and 25B). When the adjustable bed
carriage 530 is to be moved from the extended condition (or from
an intermediate position) to or towards the retracted condition,
a movable portion 572 is retracted into a motor body 574 in a controlled
manner, in the direction shown by arrow "F" in FIG. 27.
When the adjustable bed carriage 530 is to be moved from the retracted
condition (or from an intermediate position) to or towards the extended
condition, the movable portion 572 is pushed outwardly from the
motor body 574 in the direction of arrow "G" in FIG. 28.
[0113] In the preferred embodiment, the adjustable bed 564 includes
a linkage assembly (or a scissor leg assembly) 576 which includes
the adjustable bed carriage 530 with first follower struts 578
579 positioned adjacent to the first legs 540 541 respectively
and second follower smuts 535 537 positioned adjacent to the second
legs 546 547 respectively. As can be seen in FIGS. 27 and 28 the
first legs 540 541 are pivotably attached to the first caster base
580 which is positioned distal to the first end 544 of the main
bed frame 532. The second legs 546 547 are pivotably attached to
the second caster base 539 and the second caster base 539 is positioned
distal to the second end 550 of the main bed frame 532.
[0114] For convenience, the elements on only one side of the bed
564 are shown in FIGS. 27 and 28. It will be understood that the
corresponding elements on the side not shown are the same in all
relevant aspects, as those which are shown.
[0115] Preferably, each of the caster bases 580 539 is disposed
in a preselected position respectively relative to the plane 36
of the floor 34 when the linkage assembly is in the extended condition,
as shown in FIGS. 27 and 28. The first follower struts 578 579
each have upper ends 581 and lower ends 583 and the second follower
struts have upper ends 582 and lower ends 584. As can be seen in
FIGS. 25 and 25B, in the preferred embodiment, the lower ends 583
584 are pivotably attached to the caster bases 580 and 539 respectively
at pivot points 585 and 588 respectively. The upper ends 581 of
the first follower struts 578 579 are pivotably attached to the
second legs 546 547 respectively (FIG. 27). This pivotable attachment
is at predetermined pivot points 586 on the second legs 546 547
above the central pivots 552. The location of the predetermined
pivot points 586 is selected so that the follower struts 578 579
can act on the caster base 580 to maintain the caster base 580 substantially
in the preselected position relative to the plane 36 of the floor
34 as the linkage assembly 576 moves between the extended and retracted
conditions.
[0116] Similarly, the upper ends 582 of the second follower struts
535 537 are pivotably attached to the first legs 540 541 respectively.
This pivotable attachment is at predetermined pivot points 587 on
the first legs 540 541 above the central pivots 552 (FIG. 27).
The location of the pivot points is selected so that the second
follower struts 535 537 act on the second caster base 539 to maintain
the second caster base 539 substantially in the preselected position
relative to the plane 36 of the floor 34 as the linkage assembly
576 moves between the extended and retracted conditions.
[0117] In the preferred embodiment, the follower struts 578 579
535 and 537 only maintain the caster bases 580 539 respectively
in substantially the preselected positions relative to the plane
36. The movement from the preselected position has been found to
be less than 5.degree. from the horizontal.
[0118] As can be seen in FIG. 27B, the first follower struts 578
579 generally form a "modified" parallelogram with the
legs 540 541 and portions of the legs 546 547 i.e., they preferably
do not form an exact parallelogram. For clarity of illustration,
FIG. 27B shows the first leg 541 and the first follower strut 579
only. However, it will be understood that the first leg 540 and
the first follower strut 578 are included in a modified parallelogram
which is identical to that shown in FIG. 27B, in all relevant aspects.
[0119] As shown in FIG. 27B, the modified parallelogram related
to the first leg 541 and the first follower strut 579 is defined
by the central pivot 552 and pivot points 554. 585 and 586. Also,
another "modified" parallelogram (i.e., slightly different
from the modified parallelogram defined by the pivot points 552
554 585 and 586) is related to the second follower struts 535
537 and the legs 546 547 and portions of the legs 540 541.
[0120] As shown in FIG. 27B, the modified parallelogram related
to the second leg 547 and the second follower strut 537 is defined
by the pivot points 555 552 587 and 588. The modified parallelogram
related to the second leg 546 and the second follower strut 535
is not shown in FIG. 27B for clarity of illustration. It will be
understood that such modified parallelogram is the same, in all
relevant aspects, as the modified parallelogram shown in FIG. 27B.
[0121] The location of the follower struts does not provide perfect
alignment, as an exact parallelogram would, but is optimized to
provide the best alignment possible. As the bed is raised, the angle
changes above and below horizontal 60 that the bed has a level surface
at the highest and lowest positions while maintaining a substantially
level top surface through the range of motion from high to low.
(In the foregoing discussion it is assumed that deck portions are
lowered, so that the bed preferably has a substantially level top
surface.)
[0122] Pivoting movement of the legs 546 547 results in a corresponding
pivoting movement of the legs 540 541 to move the adjustable bed
carriage between the extended condition and the retracted condition,
so that the main bed frame 532 is thereby moved between a fully
raised position (FIGS. 25-28) in which the adjustable bed carriage
530 is in the extended condition and a fully lowered position (FIGS.
29-33), in which the adjustable bed carriage 530 is in the retracted
condition. For example, as shown in FIG. 27 pivoting movement of
the legs 546 in the direction indicated by arrow "H" would
result in pivoting movement of the leg 540 in the direction of arrow
"I". Also, the pivoting movement of the second leg 546
results in sliding movement of the upper end of the first leg 540
in the direction of arrow "Y" in FIG. 27. The motor 566
initiates movement of the second legs 546 547 which results in
corresponding movement of the first legs 540 541.
[0123] In use, the motor 566 is activated by a switch or other
control means (not shown), as is known in the art, to cause movement
of the linkage assembly 576 between the extended condition and the
retracted condition, and consequent movement of the main bed frame
532 relative to the plane 36 of the floor 34. For example, referring
to FIGS. 27 and 28 to move the linkage assembly 576 from the extended
condition to the retracted condition, the movable portion 572 is
retracted into the motor body 574. Retraction of the movable portion
572 is controlled by an electric motor in the motor body 574 thereby
ensuring that the retraction is at a desired rate. Also, it will
be appreciated by those skilled in the art that the retraction could
be stopped at any time, if the operator wishes to have the linkage
assembly 576 maintain any position which is intermediate between
the extended and retracted conditions. The motor 576 holds the adjustable
bed carriage 530 in any intermediate position, as required.
[0124] It will be appreciated by those skilled in the art that
the main bed frame 532 can include a chassis portion 598 and deck
portions 599 mounted on the chassis portion 598. The main deck portions
599 are for supporting a mattress (not shown), and the main deck
portions 599 are positionable in a variety of positions relative
to the chassis portion 598 as is known in the art. For example,
the deck portions 599 are positionable so as to allow adjustable
head and foot elevation, to position the patient as required. Motors
590 (FIG. 28) are preferably used to position deck portions 599
as needed, as is known in the art.
[0125] As can be seen in FIGS. 27 and 28 each of the first legs
540 541 has an upper section 650 and a lower section 651 and each
of the second legs 546 547 has an upper section 652 and a lower
section 653. Preferably, the legs 540 541 and 546 547 are configured
so as to provide maximum clearance between the floor 34 and the
adjustable bed carriage 530 through a middle portion of the adjustable
bed carriage 530 when in the retracted condition (FIGS. 29-33).
As shown in FIGS. 31 and 32 because the legs 540 541 and 546
547 each include lower sections 651 653 which are bent relative
to the substantially straight elongate upper sections 650 652 of
the legs 540 541 and 546 547 such clearance is provided in the
middle portion of the adjustable bed carriage 530 when the adjustable
bed carriage is in the retracted condition. Preferably, the lower
section is aligned at a significant angle (e.g., up to approximately
11.5.degree.) from the axis of the upper section of each leg. Due
to the relatively high clearance lift devices, movable tables and
other devices for use by or with a patient (not shown) which require
clearance under the adjustable bed carriage 530 for their operation
can be used, when the adjustable bed carriage 530 is at any height.
[0126] The use of casters on all the legs of the adjustable bed
carriage 530 permits maximum maneuverability. The directional locks
provide a simple way to control the direction of travel, as required.
The brakes on the first casters are provided for safety, so that
the bed can be maintained in a stationary position as required.
[0127] In another alternative embodiment of the adjustable bed
764 the adjustable bed 764 includes a lock assembly 720 for maintaining
the adjustable bed 764 in a stationary position. Preferably, the
lock assembly 720 includes a body 722 pivotably mounted to a first
caster base 780 including a crossbar 711 and one or more springs
724 for urging the body 722 to pivot upwardly, as will be described.
The body 722 is movable between a locked position, in which the
body 722 engages the floor 34 (FIGS. 34 35 35A, 36 and 40), and
a released position, in which the body 722 is disengaged from the
floor 34 (FIGS. 37 38 38A, 39 and 41). When the body 722 engages
the floor 34 the bed 764 is thereby held stationary.
[0128] In the preferred embodiment, the lock assembly 720 additionally
includes a lock linkage 726 pivotably mounted to the crossbar 711
(directly or indirectly) at one or more upper pivot points 728.
The upper pivot point 728 is preferably located in a flange 713
extending upwardly from the crossbar 711 (FIG. 35A). The lock linkage
726 is preferably pivotable between a low position (FIGS. 35 35A)
and a high position (FIGS. 38 38A), as will be described. The lock
assembly 720 also includes a release linkage 732 pivotably mounted
to the body 722 at one or more lower pivot points 734. The release
linkage 732 and the lock linkage 726 are pivotably attached to each
other at a middle pivot point 736 disposed between the upper and
lower pivot points 728 734. As can be seen in FIGS. 35A and 38A,
the release linkage 732 is pivotable about the middle pivot point
736 between a first (high) position (FIG. 35A) and a second (low)
position (FIG. 38A). The body 722 is maintained in the looked position
when the lock linkage 726 is in the low position, and the body 722
is maintained in the released position when the release linkage
732 is in the second position thereof, as will be described.
[0129] As can be seen in FIGS. 35 and 36 the body 722 preferably
includes a main portion 738 with two arms 739 740 extending therefrom
in substantially the same direction. Preferably, ends 742 of the
arms 739 740 are pivotably attached to the first caster base 780.
As can be seen in FIGS. 35 35A, and 36 the body 722 includes one
or more feet 743 which engage the floor 34 when the body 722 is
in the locked position. The body 722 and the feet 743 thereon are
positioned such that, when the feet 743 engage the floor 34 an
end 751 of the adjustable bed 764 (at which the lock assembly 720
is located) is slightly raised relative to the floor 34.
[0130] In the preferred embodiment, the lock assembly 720 includes
a bracket 753 which is secured to the main portion 738 of the body
722 (FIG. 39). A release pedal 754 forms part of the release linkage
732 which is pivotably mounted to the bracket 753 at the lower
pivot points 734. As can be seen in FIG. 35 the release pedal 754
is adapted to receive at least a portion of the operator's foot.
The release pedal 754 is attached to a link element 755 by a pedal
arm 756. The release link element 755 is pivotably mounted (at the
lower pivot points 734) to the bracket 753 and the release link
element 755 are also pivotably attached to the lock linkage 726
at the middle pivot point 736.
[0131] Preferably, the release linkage 732 also includes a supplemental
link 757 attached to the release link element 755 at a lower pivot
point and at the middle pivot point 736 for balancing the release
linkage 732 to prevent binding of the lock assembly 720. The release
link element 755 and the supplemental link 757 are pivotably attached
at the middle pivot point 736 to the lock linkage 726 at upper ends
758 759 thereof respectively (FIGS. 35 38).
[0132] As can be seen in FIGS. 35A and 38A, the lock linkage 726
include a body portion 760 on which a lock pedal 762 is mounted.
The lock pedal 762 is adapted to receive at least a portion of the
operator's foot.
[0133] If the operator wishes to move the body 722 to the locked
position (FIG. 35A) from the released position (FIG. 38A), the operator
presses down on the lock pedal 762 until the lock linkage 726 is
in the low position. In so doing, the operator overcomes the resistance
of the springs 724 to move the middle pivot point 736 downward,
causing upper ends 758 759 of the link element 755 and the supplemental
link 757 respectively to move downward to the positions shown in
FIG. 35A.
[0134] As can be seen in FIGS. 35A and 38A, the lock assembly 720
is an "over-center" mechanism, in which the urging by
a spring 724 of the body 722 to pivot upwardly requires the lock
linkage 726 to be in the low position (FIG. 35A) or the release
linkage 732 to be in the high position (FIG. 38A), due to compression
of the structure by the spring 724. It is preferred to use a spring
to provide compression, but other means could be suitable.
[0135] It will be evident to those skilled in the art that the
invention can take many forms, and that such forms are within the
scope of the invention as claimed. Therefore, the spirit and scope
of the appended claims should not be limited to the description
of the preferred versions contained herein. |