Abstrict An adjustable bed includes a base frame and a mattress frame having
a plurality of pivotally interconnected sections. A plurality of
links are positioned between the base frame and the mattress frame.
The mattress frame may be moved between a high position and a low
position. A single linear actuator is connected to the mattress
frame. The actuator is extendable and retractable to raise and lower
the mattress frame with the mattress frame sections in a common
plane. The actuator may also be retracted when the mattress frame
is in the low position to articulate the mattress frame sections.
Claims The embodiments of the invention in which an exclusive property
or privilege is claimed are defined as follows:
1. An adjustable bed, comprising:
a base frame;
a mattress frame including a head section and a lower section pivoted
to said head section;
mounting means operatively connected to said base frame and said
mattress frame for permitting said mattress frame to be moved between
a high position and a low position relative to the base frame with
the head section and lower section of the mattress frame lying in
a generally common plane and for permitting said head section to
pivot upwardly with respect to said lower section to define a sated
position only when said mattress frame is in the low position; and
a single actuator pivotally connected to said base frame and having
an extendable and retractable member directly connected to said
head section of said mattress frame for lowering said mattress frame
from the high position to the low position with said sections in
a horizontal orientation and for pivoting said head section upwardly
towards the seated position only when the mattress frame is in said
low position.
2. An adjustable bed as defined by claim 1 wherein said mounting
means comprises:
a first pair of pivotally interconnected links, one of said links
being pivoted to said lower section and the other of said links
being pivoted to said base frame.
3. An adjustable bed as defined by claim 2 wherein said mounting
means further comprises:
a second pair of pivotally interconnected links connected between
said head section and said base frame.
4. An adjustable bed as defined by claim 3 wherein said actuator
comprises:
a crank arm fixed to said head section.
5. An adjustable bed as defined by claim 4 wherein said actuator
extendable and retractable member is connected to said crank arm.
6. An adjustable bed as defined by claim 1 wherein said lower section
of said mattress frame comprises:
a leg section; and
a seat section pivoted to said leg section and said head section.
7. An adjustable bed as defined by claim 6 wherein said mounting
means comprises a plurality of links connected between said base
frame and said mattress frame, said links permitting said mattress
frame to be moved between said low and high positions with said
sections in a common plane.
8. An adjustable bed as defined by claim 6 further including a
leg section pivot link having an end pivoted to said leg section
and another end selectively connectable to said mounting means and
said mattress frame to fix the leg section with respect to said
seat section and permit leg section articulation with respect to
said seat section.
9. An adjustable bed as defined by claim 8 wherein said mounting
means comprises a plurality of links connected between said base
frame and said mattress frame, said links permitting said mattress
frame to be moved between said low and high positions with said
sections in a common plane.
10. An adjustable bed as defined by claim 9 wherein said actuator
comprises:
a crank arm fixed to said head section.
11. An adjustable bed as defined by claim 10 wherein said actuator
further comprises:
a drive including an extendable and retractable member, said member
being connected to said crank arm.
12. A high/low mechanism for an articulating bed of the type including
a base and a mattress support having a back section pivoted to a
leg section, said mechanism comprising:
an arm attachable to the back section;
linkage means adapted to be connected to the base and the mattress
support and permitting the support to be moved between high and
low positions relative to the base with the back and leg sections
lying in a common plane;
an actuator bracket attachable to the base; and
a linear actuator pivoted to said actuator bracket and having an
extendable and retractable element, said element connected to said
arm and wherein said arm and said linkage means are positionable
and dimensioned so that when the element is in a fully retracted
position the back section is angled to a seating position relative
to said leg section and as the element extends towards an outer
limit the back section is lowered to a flat position relative to
said leg section and the mattress support is then raised to the
high position with said sections flat.
13. A high/low mechanism as defined by claim 12 wherein said linkage
means comprises:
a first pair of pivotally interconnected links, one of said links
being pivotable to the leg section of the mattress support and the
other of said links being pivotable to the base of the bed.
14. A high/low mechanism as defined by claim 13 wherein said mounting
means further comprises:
a second pair of pivotally interconnected links connectable between
the back section of the mattress frame and the base of the bed.
15. A high/low mechanism as defined by claim 14 wherein said linkage
means further includes a control link extending between links of
said first and second pairs of links.
16. A high/low mechanism as defined by claim 15 wherein said linear
actuator includes an electric motor and a lead screw.
17. A high/low mechanism as defined by claim 12 further including:
a leg section pivot link selectively connectable to said linkage
means; and
a leg section bracket pivotally supporting said leg section pivot
link, said leg section bracket being attachable to the mattress
support. .Iadd.
18. An adjustable bed, comprising:
a base frame;
a mattress frame including a first section and a second section
pivoted to said first section;
mounting means operatively connected to said base frame and said
mattress frame for permitting said mattress frame to be moved between
a high position and a low position relative to the base frame with
the first section and second section of the mattress frame lying
in a generally common plane and for permitting said first section
to articulate with respect to said second section only when said
mattress frame is in the low position; and
a single actuator pivotally connected to said base frame and having
an extendable and retractable member directly connected to said
first section of said mattress frame for lowering said mattress
frame from the high position to the low position with said sections
in a horizontal orientation and for articulating said first section
with respect to said second section only when the mattress frame
is in said low position. .Iaddend. .Iadd.19. An adjustable bed as
defined by claim 18 wherein said mounting means comprises:
a first pair of pivotally interconnected links, one of said links
being pivoted to said second section and the other of said links
being pivoted to said base frame. .Iaddend. .Iadd.20. An adjustable
bed as defined by claim 19 wherein said mounting means further comprises:
a second pair of pivotally interconnected links connected between
said first section and said base frame. .Iaddend. .Iadd.21. An adjustable
bed as defined by claim 20 wherein said actuator comprises:
a crank arm fixed to said first section, said actuator extendable
and
retractable member being connected to said crank arm. .Iaddend.
.Iadd.22. A high/low mechanism for an articulating bed of the type
including a base and a mattress support having a first section pivoted
to a second section, said mechanism comprising:
an arm attachable to one of said sections;
linkage means adapted to be connected to the base and the mattress
support and permitting the support to be moved between high and
low positions relative to the base with the first and second sections
lying in a common plane;
an actuator bracket attachable to the base; and
a linear actuator pivoted to said actuator bracket and having an
extendable and retractable element, said element connected to said
arm and wherein said arm and said linkage means are positionable
and dimensioned so that when the element is in a fully retracted
position the first section is angled relative to said second section
and as the element extends towards an outer limit the first section
is lowered to a flat position relative to said second section and
the mattress support is then raised to the high position with said
sections flat. .Iaddend. .Iadd.23. A high/low mechanism as defined
by claim 22 wherein said linkage means comprises:
a first pair of pivotally interconnected links, one of said links
being pivotable to the first section of the mattress support and
the other of said links being pivotable to the base of the bed;
a second pair of pivotally interconnected links connectable between
the second section of the mattress frame and the base of the bed;
and
a control link extending between links of said first and second
pairs of
links. .Iaddend. .Iadd.24. A high/low mechanism as defined by claim
23 wherein said linear actuator includes an electric motor and a
lead screw. .Iaddend. .Iadd.25. A high/low mechanism as defined
by claim 23 further including:
a leg section pivot link selectively connectable to said linkage
means; and
a leg section bracket pivotally supporting said leg section pivot
link, said leg section bracket being attachable to the mattress
support. .Iaddend.
Description BACKGROUND OF THE INVENTION
The present invention relates to beds and, more particularly, to
adjustable, multiple position care beds.
Adjustable or articulating beds are commonly used in the healthcare
field. A typical bed includes a base and a mattress frame or support
which is divided into a head or back section, a seat section and
a leg or foot section. The mattress frame sections are pivotally
interconnected and have a continuous range of adjustment. The sections
are moveable from a flat, patient resting position to a seated position
with the legs bent or the legs straight and the patient's back angled
upwardly with respect to the seat section. The sections are pivoted
by motor drives, hand operated cranks or through the patient's weight.
An example of a multi-position adjustable bed may be found in commonly
owned U.S. Pat. No. 5105486 entitled ADJUSTABLE BED, which issued
on Apr. 21 1992 to Peterson. The bed disclosed therein includes
a mattress frame having a head section, a seat or intermediate section
and a foot section, which are pivotally interconnected. A first
link and positioner subassembly interconnects the head section with
the seat section and a second link and positioner subassembly interconnects
the seat section with the foot section. Each link and positioner
subassembly includes an elongated rod and a lock mechanism. The
lock mechanism selectively positions the rod with respect to a lock
housing and, hence, the mattress sections with respect to each other.
In addition, a high/low mechanism is provided for raising the mattress
frame from a low position to a high position for easier patient
care. The mattress frames may be articulated with respect to each
other when the frame is in the high and/or low positions.
Examples or other adjustable beds may be found in U.S. Pat. No.
3036314 entitled ADJUSTABLE BED, which issued on May 29 1962
to Wetzler; U.S. Pat. No. 3059248 entitled ADJUSTABLE BED, which
issued on Oct. 23 1962 to Wetzler; U.S. Pat. No. 4258445 entitled
BEDS AND ADJUSTABLE BODY SUPPORTING ASSEMBLIES, which issued on
Mar. 31 1981 to Zur and U.S. Pat. No. 4472846 entitled COUPLING
SYSTEM FOR THE MOTOR DRIVE IN AN ADJUSTABLE MOTORIZED HOSPITAL BED,
which issued on Sep. 25 1984 to Volk, Jr. et al. The Wetzler patents
disclose adjustable beds including high/low mechanisms and a single
drive motor. In Volk, Jr. et al., an adjustable bed is disclosed
wherein different adjustment functions including high/low, back
and knee adjustments are made by a single, reversible motor which
is selectively coupled to a plurality of output drive shafts by
a multiple clutch arrangement.
In the vast majority of instances, the full range of adjustment
available with beds heretofore provided is not used. The most common
mode of operation is to raise the mattress surface or sleeping surface
in a flat configuration to a high position when patient care is
being given. Raising the sleeping surface reduces back strain while
changing dressings, bandages, clothes and performing other like
operations. When a patient is left unattended, the bed is typically
placed in its lowest position in an attempt to reduce possible injury
in the event the patient tries to leave the bed or falls out of
the bed. When articulating the mattress sections, typically the
back or head section is the most frequently used mode. The back
section is raised while the bed is in the low position. Back section
elevation is used to increase the comfort of the patient while eating,
reading, conversing, watching television and the like. In addition,
a patient will typically use the back section as an arm support
while exiting the bed. As a result, exiting of the bed should be
done while the bed is in the low position. The standard operating
requirements or most typical operational modes of an articulating
bed are, therefore, a) elevated in a flat position and b) back articulation
in a low position.
A need exists for an adjustable or articulated bed of reduced complexity
from that heretofore provided, which meets the most common operating
modes or requirements and which may be manufactured at a reduced
cost with increased reliability.
SUMMARY OF THE INVENTION
In accordance with the present invention, the aforementioned needs
are fulfilled. Essentially, an adjustable bed is provided including
a mattress frame having a head or back section and a lower section
pivoted thereto. Provision is made for attaching the mattress frame
to a base frame so that it may be moved between low and high positions.
A single actuator is operatively connected to a base frame and the
head or back section of the mattress frame. The single actuator
moves the mattress frame to an elevated or high position in a flat
mode with the sections in a common plane. The single actuator articulates
the back section with respect to the lower section only when the
mattress surface or frame is in its low position.
In narrower aspects of the invention, a leg section pivot link
is included to position a leg section of the mattress frame with
respect to a seat section. As a result, different leg articulation
positions may be obtained.
The adjustable bed and actuator in accordance with the present
invention meets the most common operating requirements of the typical
articulating bed. Only a single actuator is needed to achieve high
and low positioning of the mattress frame with respect to the base
frame and also to articulate the mattress frame sections.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of an adjustable bed in accordance
with the present invention;
FIG. 2 is a fragmentary, perspective view of portions of the bed
of FIG. 1;
FIG. 3 is a side, elevational view of a bed in accordance with
the present invention showing the mattress frame in the high position;
FIG. 4 is a side, elevational view showing the mattress frame in
the low position;
FIG. 5 is a side, elevational view showing articulation of the
back section with respect to a lower section; and
FIGS. 6 7 and 8 are side, elevational views illustrating different
positions of the leg section of the mattress frame with the frame
in the low position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An adjustable bed in accordance with the present invention is illustrated
in FIGS. 1 and 2 and generally designated by the numeral 10. Bed
10 includes a base frame 12 a mattress frame 14 and a linkage or
mounting arrangement generally designated 16. In the form illustrated,
base frame 12 includes side rails 18 20 transverse ends 22 24
and a tubular headboard 26. Ends 22 24 define legs 28. Mattress
frame 14 includes a head or back section 32 an intermediate or
seat section 34 and a foot or leg section 36. Sections 34 and 36
define a lower section of the frame. Each section is defined by
a plurality of transverse wires 38 and a plurality of longitudinally
extending wires 40. The sections have a grid work configuration.
Head section 32 includes a pair of transversely spaced, generally
rectangular shaped wire loops 44. Intermediate section 34 includes
elongated straps 46. Leg section 36 includes a pair of transversely
spaced, elongated wire loops 48. Ends 50 of loops 44 are hingedly
connected to ends 52 of straps 46. Ends 54 of loops 48 are hingedly
connected to ends 56 of straps 46. As a result, head section 32
is hingedly connected to intermediate section 34 so that it may
articulate about the hinge points at ends 50 52. The lower section
of the mattress frame, including intermediate section 34 and leg
section 36 are also hingedly interconnected at ends 54 56.
As seen in FIG. 2 and as schematically illustrated in FIG. 3 linkage
arrangement 16 includes links 70 which are pivoted to base frame
18 at pivot brackets 72. A cross member 74 extends between links
70 adjacent the pivot bracket 72. Upper seat links 78 are pivoted
to links 70 adjacent their lower ends at pivot points 79 and to
mattress frame 14 at the pivotal interconnection between sections
34 and 36.
A four bar or parallelogram linkage, generally designated 82 is
also included. Linkage 82 has links 84 86 which are pivoted to
a bracket link 88 on base frame 12 and to a link 90. Link 84 pivots
to link 90 at pivot point 91 and link 86 pivots to link 90 at pivot
point 93. Link 90 extends beyond upper link 84 and is pivoted to
a bracket 92 which is fixed to head section 32. A cross member 94
(FIG. 2) extends between links 84 adjacent bracket 88. A strut 96
is fixed to cross member 74 and a strut 98 is fixed to cross member
94. A control link 102 extends between struts 96 98. As a result,
pivotal movement of link 84 about its pivot point with bracket 88
translates into pivotal movement of link 70 about its bracket 72.
The linkage arrangement, therefore, interconnects mattress frame
14 with base frame 12 so that it may be moved between a high position
illustrated in FIG. 3 and a low position illustrated in FIG. 4.
In accordance with the present invention, a single actuator or
drive means 120 is provided for raising and lowering the mattress
frame. Actuator 120 includes an electric motor 122 and an extendable
and retractable member 124. As shown in FIGS. 2 and 5 one end of
the actuator is pivoted to a strut 130 which is fixed to a cross
piece 132. Piece 132 extends between base frame side rails 18 20.
Extendable member 124 is pivoted to a crank arm 136. Crank 136 is
fixed to head or back section 32 adjacent a pivot or hinge point
142 between back section 32 and intermediate section 34. Crank arm
136 engages the intermediate section undersurface, which forms a
stop, so that clockwise movement of section 32 about pivot point
142 is limited. Section 32 can be moved clockwise only to a flat
or horizontal configuration with section 32 in the same plane as
section 34. In a presently existing embodiment, actuator 120 is
a linear actuator of the type marketed by Fasco under the model
designation VW76. Electric motor 122 rotates a lead screw 145 which
threadably engages extendable and retractable member 124.
A leg pivot link 160 includes an upper end 162 which is pivoted
to leg section 36 at brackets 163. A lower end 164 is attachable
to different portions of the bed. In the form shown in FIGS. 2 and
3 intermediate section 34 includes a fixed depending tab 165 defining
an aperture 167 for receipt of end 164 of link 160. Seat link 78
defines an extension 169 having an aperture or pivot point 171.
As shown in FIGS. 6 and 7 another leg link 173 may also be included.
Link 173 is pivotally connected to links 70 78 at pivot point 79
and to links 84 90 at pivot point 91. Leg link 173 defines apertures
or pivot points 182 186. Link 160 permits adjustment of the articulation
of the leg section 36 with respect to the seat section 34.
OPERATION
When actuator 120 is at its fully extended position, as shown in
FIG. 3 mattress frame 14 is flat or horizontal with sections 32
34 and 36 all lying in a common plane. Mattress section 14 is at
its high position with respect to base frame 12. Movement of mattress
frame 14 to this position with respect to the base frame 12 is controlled
by the links 70 78 82 90 and 92. Crank arm 136 is in engagement
with section 34 of the mattress frame. Actuator 120 retracts member
124 to a low position as shown in FIG. 4. Sections 32 34 and 36
remain in the common plane. Link 70 and parallelogram linkage 82
have bee lowered to their lowermost positions. Further movement
or retraction of member 124 causes back section 32 to pivot about
point 142 to various raised or articulated positions FIG. 5). When
the actuator is at its fully retracted position, the back or head
section will be at its full upright or seated position, illustrated
in solid lines in FIG. 5. Seat section 34 drops below horizontal
and leg section 36 remains in the same plane therewith.
When actuator 120 is reversed and member 124 is moved towards its
outer limits, section 32 will articulate back to the horizontal
position and arm 136 will abut the stops defined by section 34.
Continued extension of actuator 120 shifts mattress frame 14 from
the low position, shown in FIG. 4 to the high position, shown in
FIG. 3.
A single actuator, therefore, provides high and low positioning
of the mattress frame for ease of patient care. Articulation of
the back section with respect to the lower section thereof occurs
only when the mattress frame is in its low position. The adjustable
bed in accordance with the present invention, therefore, meets the
majority of operation requirements of a typical articulating bed.
Leg section articulation, that is angled positioning of section
36 with respect to section 34 is achieved through placement of
the leg pivot link 160. When link 160 is attached to seat tab 165
at aperture 167 it extends substantially parallel to leg section
36. Section 36 will remain in the same plane with seat section 34
(FIGS. 3 4 and 5). Pivot link 160 is in effect locked with respect
to the seat and the lower section.
As shown in FIG. 6 the end 164 of pivot link 160 may be moved
to pivot point 182 on link 187 and which is rearwardly of bracket
72. When in this position, the leg section 36 will be elevated with
respect to seat section 34 during back articulation.
As shown in FIG. 7 end 164 of leg link 160 may be positioned so
that it is within aperture 186 of link 173. When so positioned,
link 160 is substantially parallel to seat link 78. When in such
a position, minimal leg section articulation is achieved. Leg section
36 remains in a substantially horizontal plane, while the back section
32 and seat section 34 articulate with respect to each other.
As shown in FIG. 8 leg pivot link 160 may be pivoted forwardly
so that the lower end 164 thereof engages pivot point 171 which
is defined by seat link 78. When end 164 is thus moved towards head
section 32 leg section 36 will drop with respect to seat section
34 providing a knee break for the patient. When the bed is to be
moved so that the mattress frame is raised to the high position,
leg link 160 is returned to its position on seat section tab 165
parallel to leg section 36.
The use of the pivotally connected leg link, therefore, between
the foot section of the bed and different locations on the bed yield
different characteristics of leg articulation. The specific elevation
of the leg section and/or bending at the knee required by different
patients for comfort and rehabilitation is readily achieved.
A single linear actuator operates in the lift mode in accordance
with the present invention at one limit to raise the mattress frame
to a high position for proper patient care and also for lowering
the mattress frame to its lowest most position for normal patient
use. The same actuator also achieves back articulation only when
the bed is in the lowest position. Multiple actuators, cranks and
motors are eliminated. A bed in accordance with the present invention
is of a significantly reduced complexity from prior motorized beds
while satisfying the vast majority of the operating modes or requirements
for an adjustable bed in a healthcare environment. The adjustable
bed in accordance with the present invention is relatively easily
manufactured at reduced costs from that heretofore experienced.
In view of the above description, those of ordinary skill in the
art may envision various modifications which would not depart from
the inventive concepts disclosed herein. For example, if leg articulation
is not needed, the mattress frame could include only two articulating
sections, namely a head section and a lower section. It is expressly
intended, therefore, that the above should be considered as only
that of the preferred embodiment. The true spirit an scope of the
present invention may be determined by reference to the appended
claims. |