Abstrict An adjustable bed is shown having an adjustable frame which supports
an articulated mattress. The frame mounts a single motor which lifts
a first adjustable section thereof through a threaded drive shaft.
A push linkage connects from the first adjustable section of the
frame back to the frame itself where a conversion plate connects
the push linkage to a pull linkage. The pull linkage connects to
a second adjustable section of the frame. The single motor thus
raises the first adjustable section and, through the linkage, the
second adjustable section.
Claims I claim:
1. In an adjustable bed having an adjustable frame that supports
an articulated mattress including at least first, second and third
sections adjusted by adjustment of said frame, the improvement comprising:
support sections forming the sides of said frame;
at least one lateral support member joining said support sections;
a single motor mounted within said frame upon said lateral support
member;
said frame having a first adjustable section to support and adjust
said first section of said articulated mattress and a second adjustable
section to support and adjust said third section of said mattress,
said second section thereof being mounted upon said frame;
said first and second adjustable sections pivotally mounted upon
said adjustable frame;
mechanical drive means connecting said single motor to said first
adjustable section of said frame for raising and lowering said first
section;
linkage means connected from said first adjustable section to said
lateral support member and then to said second adjustable section
for raising and lowering said second adjustable section, including:
(a) a pivot converter mounted upon said lateral support member;
(b) a first push linkage means attached from said first adjustable
section to said pivot converter; and
(c) a second pull linkage means attached from said pivot converter
to said second adjustable section wherein the raising of said first
adjustable section will push said first push linkage against said
converter for pulling said second pull linkage against said second
adjustable section for raising said second adjustable section.
2. An adjustable bed, as claimed in claim 1 wherein:
said first push linkage means includes a pair of pushing arms pivotally
connected from said first adjustable section to said pivot converter;
and
said second pull linkage means includes a single arm pivotally
connecting said pivot converter to said second adjustable section.
3. An adjustable bed, as claimed in claim 2 wherein said second
pull linkage means includes two linkage elements joined at each
end by serrated end sections to permit the longitudinal adjustment
of said linkage to assure that said articulated mattress lies flat
upon said frame.
4. An adjustable bed, as claimed in claim 1 wherein said single
motor and said pivot converter each pivotally mount upon connector
means attached to said lateral support member.
5. An adjustable bed, as claimed in claim 1 wherein said first
section of said articulated mattress is a back section, said second
section thereof is a seat section, and said third section thereof
is a leg section having a thigh and lower leg section and additionally
comprising:
a third adjustable section of said frame pivotally connected to
said second adjustable section of said frame wherein adjustment
of said second section by said linkage means also adjusts said third
adjustable section.
6. An adjustable bed, as claimed in claim 1 wherein said adjustable
frame includes:
a bed frame;
an adjustable power drive module nested within said bed frame;
said support sections form the sides of said power drive module;
and
said first and second adjustable sections pivotally mounted upon
the ends of said support section.
7. An adjustable bed, as claimed in claim 1 wherein said mechanical
drive means connecting said sngle motor to said first adjustable
section includes:
a threaded shaft driven by said single motor;
a threaded bushing mounted upon said shaft; and
pivot means mounting said threaded bushing to said first adjustable
section.
8. An adjustable bed, as claimed in claim 7 wherein said threaded
bushing is formed from a moldable, low friction material to provide
smooth, low friction operation of said threaded shaft and said pivot
means.
9. In an adjustable bed driven by a single motor having an adjustable
frame that supports an articulated mattress including at least first,
second and third sections adjusted by adjustment of said frame,
the improvement comprising:
side support sections forming the sides of said adjustable frame;
at least one lateral support member joining said side support sections;
a single motor mounted upon said lateral support member;
first and second adjustable sections pivotally mounted upon opposite
ends of said side support sections to respectively support and adjust
said first and third sections of said articulated mattress, said
second mattress section mounted upon said frame;
drive means connecting said single motor to said adjustable section
of said frame for raising and lowering said first section;
pivot means mounted upon said lateral support member;
first linkage means mounted between said first adjustable section
and said pivot means; and
second linkage means mounted between said pivot means and said
second adjustable section wherein the raising of said first adjustable
section will push said first linkage against said pivot means for
pulling said second linkage against said second adjustable section
to raise said second adjustable section.
10. In an adjustable bed, as claimed in claim 9 wherein said drive
means connecting said motor to said first adjustable means is in
tension, said first linkage means is in compression, and said second
linkage means is in tension during adjustment of said frame.
11. In an adjustable bed, as claimed in claim 9 wherein said first
linkage means include a pair of parallelly connected links for increased
strength and said second linkage includes a pair of serially connected
links for adjustability.
Description BACKGROUND OF THE INVENTION
The concept of an adjustable bed has been known for some time.
Early adjustable beds utilized several motors to adjust a bed frame
upon which an articulated mattress rested. A typical articulated
mattress might be divided into three, four or more sections each
mounted upon an adjustable frame section and each driven by an electric
motor. Examples of adjustable beds utilizing at least two motors
may be found in the following patents: U.S. Pat. No. 2500742 by
A. J. Taylor; U.S. Pat. No. 2582565 by E. V. Schnippel, et al.;
U.S. Pat. No. 3262133 by S. W. Beitzel; and U.S. Pat. No. 3644946
by L. W. Swatt.
Early adjustable beds were manufactured and sold to hospitals and
convalescent homes where individuals could be expected to be confined
to a bed for an extended period of time. However, with an increasingly
affluent society, the market for adjustable beds has been expanding
to home usage. During this same time period, the economy has experienced
a general inflation. Thus, it is desired to provide an adjustable
bed with as few components as possible for economy while retaining
as many comfort features as possible.
One component which could be eliminated is the use of a second
motor. An example of a single motor adjustable bed wherein the motor
is a hydraulic pump which uses two hydraulic cylinders may be found
in U.S. Pat. No. 2520849 by G. D. McVicker. Another adjustable
bed arrangement in which a single motor drives two adjustable sections
through a transmission is found in U.S. Pat. No. 3191196 by L.
E. Holm or U.S. Pat. No. 3278952 also by L. E. Holm. A hospital
bed utilizing a single motor and three clutches to obtain adjustment
of an articulated mattress is shown in U.S. Pat. No. 3465373 by
H. A. Wilson.
While the foregoing examples represent various approaches for powering
an adjustable bed, each of the adjustable beds shown in the examples
cited and known in the prior art require complicated drive mechanisms
when but a single motor is utilized.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide
an adjustable bed which may be manufactured with a rugged and reliable
and economical design utilizing fewer components including one motor.
A further object of the present invention is to provide an adjustable
bed which may be manufactured with a modular configuration that
can be assembled and disassembled for easy shipping, storage and
reassembly.
A still further object of the present invention is to provide a
linkage mechanism which may be retrofit into existing adjustable
beds and which is rugged, reliable and economical.
In accomplishing these and other objects there is provided an adjustable
articulated mattress including head, seat, thigh and lower leg sections
which rests upon a frame that includes a power drive module that,
in turn, nests within a bed frame. The power module comprises a
pair of central support sections joined by a lateral support member
which supports, at each end, a first and second adjustable section.
A single drive motor is mounted upon the lateral support member
for driving the first adjustable section through a threaded drive
shaft.
Mounted from the first adjustable section back to the lateral support
member and then to the second adjustable section of the power drive
module is a linkage arrangement which is pushed by the first adjustable
section and which pulls the second adjustable section into the desired
position. In the preferred embodiment, shown herein as an example,
the second adjustable section of the module is provided with a third
adjustable section which hinges from the outer end thereof to adjustably
support the lower leg portion of the articulated mattress.
DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention summarized above and
of the objects and advantages thereof, the reader's attention is
directed to the following specification and accompanying drawings,
wherein:
FIG. 1 is a top plane view of a frame including a power drive module
nested within a bed frame which mounts the module showing a single
motor drive of the present invention mounted within the module;
FIG. 2 is a cross-sectional view of the power drive module which
mounts the single motor drive linkage of the present invention taken
along line 2--2 of FIG. 1; and
FIG. 3 is a cross-sectional view of the single drive motor linkage
taken along line 3--3 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings, FIG. 1 shows an adjustable articulated
bed including a frame 10 formed from a bed frame 12 and a power
module 14 nested within the frame. The bed frame 12 consists of
two longitudinal supports 16 joined by two cross supports 18. The
opposite ends of the longitudinal supports 16 are bent at right
angles to form vertical, frame support legs 20 FIG. 2. The lower
portion of the vertical legs 20 may be provided with sockets or
other suitable means for mounting casters, not shown, which assists
in moving the bed from place to place. Each cross support 18 is
attached to the longitudinal supports 16 by suitable nuts and bolts,
22 and 24.
The power drive module 14 includes a pair of central support sections
26 which are L-shaped in cross section each with the shorter leg
27 thereof extending outwardly therefrom to land upon the longitudinal
support 16 of the frame 12. A tubular lateral support member 30
having a square cross section passes between the central support
sections 26 for securing these sections of the power module 14 in
a spaced, parallel relationship. The square cross section of the
lateral support member 30 is inserted into a square aperture 32
found within each support member 26. In stamping the support members
26 the square aperture 32 is formed by a U-shaped stamp which bends
the material removed from the square aperture at right angles to
the surface of the support members to form tabs 34. The tabs 34
extend under the square cross section of lateral member 30 to support
that member and align the central support sections 26 with that
member. An aperture may be tapped in the support member 30 to receive
a screw 36 for fastening each central support section 26 to the
lateral member.
Mounted midway between the central support sections 26 on support
member 30 are a pair of motor connecting plates 38 which have been
stamped to produce a square aperture 39 FIG. 2 whose material
has been bent at a right angle to produce a tab 40 similar to tab
34. Again, the lateral support member 30 may be tapped to receive
mounting screws 36 which secure the motor connectors to the support
member 30. The motor connectors 38 are stamped in the shape of a
rhombus having apertures at one end through which a pin 42 may be
inserted to pivotally mount a drive motor 44. The single drive motor
44 is provided with a gear train 46 having tabs 48 extending from
its lower surface through which the pin 42 passes to provide the
pivotal mounting. The gear train 46 drives a threaded shaft 50 which
passes through a threaded, low friction bushing 52 which may be
constructed from a moldable, low friction material, such as nylon.
Mounted to the lower outer corners of each of the central support
sections 26 is one leg of an H-shaped torque arm 54 FIG. 2. Each
torque arm 54 is constructed from two triangularly shaped plates
56 whose inner ends pivotally connect to the central support sections
26. The pivotal connections are accomplished by stamping a boss
58 into the central support section 26 to provide a raised anular
surface against which the plate 56 may ride. The boss 58 is drilled
to provide an aperture into which is inserted a shouldered stud
60 which is retained therein by welding. The plate 56 is drilled
to provide a larger aperture which receives a pair of shouldered,
low friction bushings 62 through which the stud 60 is inserted so
that the shoulders of the bushings assure the separation of the
plate 56 from the boss 58. A self-locking flange nut 64 retains
the plate 56 upon the stud. Between each plate 56 is welded a cross
member 66 which completes the H-shaped torque arm subassembly 54.
The right-hand, H-shaped torque arm subassembly 54 in combination
with pivot arm 74 and horizontal support members 76 to be described
herein below, form a first adjustable section of the power drive
module 14 that raises and lowers one section of the articulated
mattress.
Extending perpendicularly from the center of the cross member 66
of H-shaped torque arm 56 are a pair of bushing mounting tabs 68
which may be welded to the cross member 66 and which are provided
with threaded apertures for receiving shouldered bolts 70 each having
a reduced shouldered portion 72 that slidably fit into suitable
apertures within the side wall of the bushing 52 to pivotally retain
the bushing 52 between tabs 68. The bushing 52 and tabs 68 form
the first link in a single motor drive linkage 73 FIG. 3.
Connected to the outer end of the triangular plates 56 which form
the H-shaped torque arms 54 are a pair of upwardly extending pivot
arms 74 which are pivotally attached to the plate 56 by use of the
stud 60 busining 62 and flange nut 64. Similarly, a pair of horizontal
support member 76 are pivotally mounted about bosses 58 located
in the upper, outer corners of the central support sections 26 by
the use of the stud 60 bushing 62 and flange nut 64. In the positions
shown, the horizontal support members 76 extend parallel with the
central support section 26. Pivotally connected to the horizontal
support members 76 are the pivot arms 74 which are attached by the
stud, busing, and jam nut 60 62 and 64 respectively.
It will be understood from the foregoing description that the structural
elements attached to the right-hand end of the central support sections
26 form a parallelogram which may be raised when motor 44 is energized
for rotating the threaded shaft 50. Rotation of the threaded shaft
50 causes the bushing 52 to move along the longitudinal axis of
the shaft 50 for rotating the H-shaped torque arm 54 about the pivot
point located at the lower, outer ends of the central support sections
26. This causes the first adjustable section of the power module
formed by the members 56 74 and 76 to rotate in an upward or downward
direction with the members 56 and 76 remaining generally parallel
to one another; while the member 74 remains generally parallel to
a line drawn between the pivot points located in the upper and lower
corners of the central supported sections 26.
The structural parallelogram thus described is also found at the
left-hand end of the power drive module 14 which forms a second
adjustable section of the power module 14 that may be moved up or
down by a suitable drive mechanisms such as linkage 73.
As seen in FIG. 2 an articulated mattress 78 formed from a plurality
of sections rests upon the drive module 14. In the embodiment shown,
the mattress is divided into four sections including a back section
80 seat section 82 thigh 84 and lower leg section 86. The seat
section 82 mounts upon the center support sections 26 of module
14 and is secured thereto by screws, not shown. Similarly, the back
section 80 mounts upon the right-hand horizontal support members
76 and is secured thereto by screws to form a back raising section;
while the thigh section 74 mounts upon the left-hand horizontal
support members 76 that form the leg rising section of the power
drive module 14.
The embodiment for adjusting the lower leg mattress section 86
FIG. 2 includes a hinge 88 which is pivotally attached to the outer
end of the left-hand horizontal support member 76. This hinge is
secured to the lower leg section 86 of the mattress 78 by screws,
not shown. The far end of the lower leg section 86 is supported
by a pair of J-shaped pivotal linkages 90 that are removably mounted
upon the cross support 18 of the frame 12 by a U-shaped hinge element
92 which receives the pivotal linkages 90 between the upwardly extending
legs and retains them by use of hinge pins 94. An L-shaped pivot
hinge 96 is mounted at the end of the short leg of each J-shaped
linkage to attach the outside edge of the mattress section 86.
The single motor drive linkage 73 transfers the mechanical motion
of the first right-hand adjustable section to the second left-hand
adjustable section of the power module 14 through a unique push-pull
linkage arrangement which may be adjusted to assure that the articulated
mattress 78 lies in a coplanar position.
Welded to the right-hand cross member 66 is a tab 98 FIG. 3 which
extends at right angles to member 66 and which is substantially
identical to the tab 68. The outermost end of tab 98 is pivotally
connected to a pair of push linkage arms 100 by a pin 102. Pin 102
may be formed in a manner similar to the stud, bushing, and flange
nut arrangement 60 62 and 64 described above or may be attached
by other suitable means, such as cotter pins. The first push linkage
formed by push arms 100 pivotally connects to a pivoted converter
104 through the use of a second pin 106. The converter plate 104
is generally triangular with a notched section which rests upon
lateral support member 30 to form a stop for the single motor drive
linkage 73. The converter 104 is connected to member 30 by a connector
38 having a tab 40 which is secured to the member 30 by a screw
36. Converter 104 pivotally attaches to the connector 38 by a post
108 which mounts low friction bushings having flanges thereon that
separate the converter 104 from the connector 38. On the opposite
end of the converter 104 from the pivotal connection of the push
linkage 100 is connected a pull linkage 110. In the preferred embodiment,
there is but one pull linkage 110 used since there is no tendency
to buckle when the linkage is placed in tension.
However, the linkage 110 is constructed from two pieces having
their mating ends offset and serrated to permit an adjustable connection.
The first link 111 of the pull linkage 110 pivotally connects to
the converter 104 by a pin 112; while its opposite, serrated end
is provided with a clearance hole through which a bolt 114 is inserted.
Bolt 114 passes through a slot 116 in the serrated end of a second
pull link 118 of linkage 110. By loosening a nut 120 upon the bolt
114 it is possible to adjust the length of the pull linkage 110.
The single motor drive linkage 73 is completed by a tab 122 welded
to the left-hand cross member 66 which pivotally secures the linkage
110 thereto by a pin 124.
From the foregoing, it will be noted that the adjustable articulated
bed may be driven by a single motor 44 through the drive linkage
73. As the motor 44 causes the shaft 50 to turn, the bushing 52
travels along the longitudinal axis of shaft 50 for raising or lowering
the structural parallelogram formed on the right-hand side of the
power module 14 by elements 56 74 and 76. The rotational motion
of the cross member 66 about the pivot point in the lower right-hand
corner of support sections 26 causes tab 98 to push the linkages
100 against the converter 104. Converter 104 then rotates about
pin 108 and pulls the linkage 110 which, in turn, pulls the tab
122 and rotates the left-hand cross member 66 for raising the thigh
section 84 of the mattress 78. As the thigh section of the mattress
raises under the urging of the parallelogram formed by the left-hand
element 56 74 and 76 the lower leg section 86 of the mattress
follows but remains generally parallel to the original plane of
the mattress.
Thus, it will be seen that the single motor 44 is capable of adjusting
the four sectioned articulated mattress 78. By use of the flat on
convertor 104 which engages the lateral support 30 it is possible
to reference the articulated mattress to a horizontal position.
Using the flat as a reference point, the linkage 110 may be adjusted
to assure that the thigh and lower leg portions are horizontal when
the back portion is in that position.
The single motor drive of the present invention may be utilized
in existing articulated beds or in beds of a new design. The plate
38 is arranged with a square apperture for retrofit upon square
cross sectioned members 30. Similarly, pivot pins 102 106 108
112 and 124 may be easily removed and replaced by the use of threads
or cotter pins for ease of retrofitting or module construction.
While the present invention has been described within a particular
embodiment of an articulated bed, it will be understood that other
embodiments are also possible. Accordingly, the present invention
should be limited only by the appended claims. |