US 3010121 A
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Description (OCR text may contain errors)
Nov. 28, 1961 A. c. E. BREACH 3,010,121
ADJUSTABLE SUPPORT DEVICE Filed April '7, 1958 2 Sheets-Sheet J.
Nov. 28, 191 c, BREACH 3,91%,121
ADJUSTABLE SUPPORT DEVICE Filed April 7, 1958 2 Sheets-Sheet 2 Unite tates at This invention relates to adjustable support structure and especially concerns invalid adjustable beds.
An object of the invention is to provide an adjustable support structure which may be adjusted by the user from a reclining or lying down position to a sitting up position and vice versa.
According to the present invention an adjustable support device comprises three parts, a seat portion and two members constituting U-shaped leg and back rests, each of said members being hingedly connected to opposite ends of the seat portion, the back and leg rests being actuated by at least one pivotal link mechanism, whereby movement of the seat portion or either of said back and leg rests about its hinge causes movement of the remaining parts.
Preferably two link mechanisms are provided each mechanism comprising three bars or the like pivoted together, one end of each mechanism being fixed to the back rest and the other end being fixed to the leg rest.
The supporting structure may be carried by a base frame which may be mounted upon castor wheels and the three parts of the structure may be pivotally mounted on the frame by means of a pivot rod or the like, hereinafter referred to as a rod, situated adjacent or being provided by the hinge rod between the seat and leg rests, which rod extends across the frame.
One or more radius arms may also be provided pivotally mounted between the back rest and the frame. The arrangement of the radius arms is such that they control the movement of the back rest when the position thereof is being changed.
The invention is illustrated in the accompanying diagrammatic drawing in which:
FIGURE 1 is a side elevation showing one embodiment of the structure constituting an invalid adjustable bed and showing one form of the means for effecting adjustment of the structure;
, FIGURE 2 is a view corresponding to FIGURE 1 showing the structure moved into such a position that it forms a seat and showing an alternative form of the means for effecting adjustment of the structure;
FIGURE 3 is an end elevation of FIGURE 1;
FIGURE 4 is a detail view showing part of the pivotal link mechanism; and
FIGURE 5 is an enlarged fragmentary detail elevational view of a locking tube, a releasing mechanism therefor, and associated parts.
Referring to the drawing, an adjustable support structure comprises three parts, a seat portion 1, and two U-shaped members forming back and leg rests 2, 3, each of said members being hingedly connected at 4-, 5 to opposite ends of the seat portion 1. The back rest 2 is connected at each side to the leg rest 3 by means of a pivotal link ates through a reduction gear 4-3 (see mechanism comprising three bars 6, 7 and 8, the bar 6 being fixed at one end to the back rest 2, a reinforcing bar 9 also extending between the back rest 2 and bar 6. The other end of the bar 6 is pivotally connected at 10 to one end of the bar 7 and the other end of the bar 7 is pivotally attached to the bar 8, the other end of which bar 8 is firmly fixed to the leg rest 3.
The seat portion and back and leg rests are mounted on a rectangular frame generally indicated at 11. The frame 11 comprises two side members 12 and front and rear end bars 13. It is also provided with an upstanding rail 14 on each side. The frame is mounted on castor wheels 15, said wheels being provided with an adjustable brake device 16.
The back and leg rests 2, 3 and the seat portion 1 are attached to the frame 11 by means of the hinged connection at 5 which extends outwardlyfrom the junction between the seat portion 1 and leg rest 3 on each side and is mounted at each side on a the rail 14 of the frame 11.
Two radius arms 18 are provided one on each side of the back rest to limit the movement thereof, one end of each radius arm being pivotally attached to the back rest 2 adjacent the hinged connection 4, the other end of each radius arm being pivotally attached to a transverse member mounted between the side members 12 of the frame 11.
Movement of the bed is caused by a power unit which may comprise a hydraulic jack 19 (see FIGURE 1) or an electric motor 25 (see FIGURE 2). When a hydraulic jack 19 is used this works between a point midway between the ends of rear bar 13 of the frame 11 and a point about midway between the ends of the back rest 2. Operation of the jack 19 is by means of a pump handle 20* operating a pump 21 attached at one side of the bed and the handle 21 extending to a position Within reach of the user of the bed. The pump is connected to the jack through connecting pipes 22, 23. The pump includes a reversing valve operated by a handle 24 whereby the jack may be caused either to raise or lower the back rest as desired.
When an electric motor 25 is provided this may be controlled through a push button 41 or the like on a plate 42 within reach of the user of the bed. The motor 25 oper- FIGURE 2) to rotate a screwed rod 26 which engages with a nut 27 carrying a pivotal arm 28 attached to the back rest 2. Rotation of the screwed rod 26 causes movement of the nut '27 therealong and consequent up or down movement of the back rest 2 according to the direction of rotation of screwed rod 26.
A locking device is provided by two bracing tubes 29 attached to the free end of the leg rest 3 and extending downwardly to rest against the front bar 13 of the frame 11. I
The lower ends of the tubes 29 have an extension 31 to prevent the tubes slipping oh the front bar 13. The arrangement is such that when the lower ends of the tubes 29-rest against the front bar 13, the leg rest 3 is locked in the horizontal position but when the tubes 29 are released from engagement with front bar 13, the leg rest 3 will drop slightly until the sides of tubes 29rest against the side of front bar 13 whenafter tubes 29 may slide over front bar 13. r
trunnion 17 mounted on A release mechanism is provided to move the tubes 29 so that their ends disengage from the front bar 13. The release mechanism comprises a crossbar 32 (see FIGURE 3) extending across the bed and being formed with two shoulders 33, one shoulder being provided coincident with each of the tubes 29'. To release the tubes 29, that is to disengage the tube lower ends from the cross bar 13, the cross bar 32 is rotated clockwise from the position shown in FIGURE 1, causing the shoulders 33 to swing the tubes 29 counter clockwise about their pivots on the leg rest 3 until the tube lower ends are clear of the cross bar 13. The leg rest may then swing downwardly about the hinge rod while the tubes 29 rest and slide on the cross bar 13 until the parts have reached the positions shown in FIGURE 2.
In order to allow the back rest 2 of the structure to be at a slight angle to the horizontal whilst the leg rest 3 remains horizontahthe bar 7 of the pivotal link mechanism includes an adjustment device 34. To provide this the bar 7 is formed in two sections 35, 36 (see FIGURE 4) one end of section 36 being drilled to provide a hole to accommodate a neck portion of reduced diameter formed on section 35, whereby the length of bar 7 may be adjusted by sliding section 35 into and out from the hole in section 36. Holes 37 are provided in both sections 35 and 36 so that a locking pin may be inserted to retain the sections 35, 36 in any desired position.
A tube 33 is provided adjacent one side of each trunnion 17 to receive a support arm 39 (see FIGURE 2) for use when the support structure has been adjusted to take the form of a seat.
The free end of the leg rest 3 is formed with a single transverse U-shaped member 48 to provide a bottom for the bed and a step to assist the invalid in descending from the bed to the floor.
The back rest 2, seat portion 1 and leg rest 3 of the bed each comprise a rigid framework which may be covered with a resin bonded fibre or other backing for a mattress which may conveniently be made of the material known under the registered trademark Dunlopillo.
In operation, when it is desired to alter the position of the seat portion 1, back or leg rests 2, 3, the user of the structure may operate the electric motor 25 by means of the push button 41 conveniently situated on the plate 42 at the side on the structure. Alternatively if the hydraulic jack 19 is provided the patient may operate this by means of the handle 20. Whatever power unit is used however movement of the back rest 2 is caused, which movement is controlled by means of the radius arms 18, the point on the back rest 2 to which each radius arm 18 is pivotally connected being constrained to move around the circumference of a circle having its centre at the point of pivotal attachment of the radius arm 18 to the frame.
Movement of the back rest 2 produces, by means of the link mechanism and the hinged connection 4 between the back rest 2 and the seat portion 1, a slow concerted movement of the seat portion 1 and back rest 2 about their respective pivotal axis.
It will be appreciated that, when the structure is in the fully sitting up position as shown in FIGURE 2, the seat portion 1 will assume an angle to the horizontal thus avoiding the position in which the patient is propped up with his back at an angle to the horizontal whilst his upper legs remain in a horizontal plane, which position has been the cause of pressure sores and the like. When the structure is in the sitting up position, the leg rest 3 is tilted downwardly about its hinged connection to the seat portion 1 so as to provide a natural supporting surface for the legs below the knee.
When the leg rest is in the horizontal position and it is desired to lock it in this position so that itmay not be adjusted, the foot of the leg rest 3 is pulled slightly upwards from its normal position which is at an angle of about 2 below the horizontal, until the lower ends of the tubes 29 slip over the front bar 13 whereupon downward movement of the leg rest 3 can occur. When it is desired once more to allow adjustment of the structure by the user, therelease mechanism 32, 33 is rocked clockwise as viewed in FIGURE 1, causing the shoulders 33 to swing the tubes 29 clockwise and disengage the tube lower ends from the bar 13. The leg rest 3 will then drop slightly down from the horizontal to its nor trial operating position so that the sides of tubes 29 rest against front bar 13, whenafter the structure may be adjusted at will.
When it is desired to adjust the back rest 2 and seat portion 1 relative to the legrest 3, this latter is locked in position, the locking pin is pulled out from the hole 37 and relative movement between the sections 35 and 36 of the link 7 may then take place.
Thus the back rest 2 and seat portion 1 may perform their concerted movements leaving the leg rest 3 in the horizontal position. The locking pin will then be reinserted in a new hole 37 in the section 35 and the original hole 37 in the section 36 to provide once again a rigid bar 7.
The back rest 2 and seat portion 1 may be held stationary by the hydraulic jack 19 or the electric motor 25 and screw and nut drive 26, 27; and the locking pin withdrawn from the hole 37 so as to permit relative pivotal movement of the leg rest whilst the seat portion 1 and back rest 2 remain in stationary positions. The positions of the structure which may thus be obtained are useful in the nursing of certain surgical and medical cases.
It will be appreciated that the support structure may also be converted to serve as a reclining couch, seat or ordinary bed and that the back rest, seat portion and leg rest, together with their pivotal link mechanism, may be supported on a household bedstead.
What is claimed is:
1. A support structure, convertible for use as a chair or as a bed, comprising a supporting framework, a seat portion hingedly connected at its front end to said sup porting framework, a leg rest hingedly connected to the front end of said seat portion, a back rest hingedly connected to the rear end of said seat portion, at least one radius arm pivotally mounted between said back rest and said supporting framework, operating means operable by the occupant and mounted between and operatively connecting said back rest and said supporting framework to effect pivotal movement between said back rest and said seat portion and to stabilize said back rest and said seat portion, at least one pivotal link mechanism mounted between and operatively connecting said leg rest and said back rest, whereby movement of said back rest is transmitted to said leg rest to cause simultaneous relative movement between said leg rest, said seat portion and said back rest and to cause movement of said structure from a bed position to a chair position or vice versa, said structure also including at least one releasable lock ing member mounted between said leg rest and said supporting framework for locking said leg rest in a horizontal position, and means for adjusting said pivotal link mechanism whilst said locking member is effective for holding said leg rest in horizontal position, whereby relative movement of said seat portion and said back rest can be effected by operation of said operating means whilst said leg rest is held in a stationary position by said locking means and pivotal movement of said leg rest can be effected when said locking means is released and whilst said seat portion and said back rest are stabilized in stationary positions by said operating means.
2. A support structure as claimed in claim 1, in which the adjusting means is included in one link of said pivotal link mechanism to render said one link adjustable in length, said one link being formed in two telescoped parts which parts are adjustable one within the other, corresponding transverse holes being formed in both of said parts, .and a locking pin receivable in selected pairs of 5 said holes to retain said two parts in a predetermined relative position.
3. A support structure as claimed in claim 2, in which the means operable by the occupant comprises a hydraulic jack mechanism.
4. A support structure as claimed in claim 2, in which the means operable by the occupant comprises an electric motor mounted on said supporting framework, a screwthreaded rod in driving connection with said motor, a correspondingly screw-thread nut mounted for movement along said rod, and a connecting arm mounted between and operatively connecting said nut and said back rest.
References Cited in the file of this patent UNITED STATES PATENTS Cuthell v Nov. 28, 1933 Oapron Aug. 29, 1939 Loxley June 12, 1951 Burke Apr. 13, 1954 Miller et al Apr. 27, 1954 FOREIGN PATENTS Great Britain May 8, 1939