Title:
APPARATUS FOR LIFTING A BED MATTRESS
Kind Code:
A1


Abstract:
Apparatus suitable for lifting a bed mattress, the apparatus comprising a carriage including a mattress support structure upon which a bed mattress can be carried and an elevating mechanism operatively connected to the mattress support structure for moving the mattress support structure between a lowered and a raised position. The apparatus further includes a bedding retention device operatively connected to the carriage so that when the mattress support structure is in the raised position, the bedding retention device is disposed at a lower position than the mattress support structure, and in the lowered position it is caused to adopt a retention position as a result of relative movement between the bedding retention device and the mattress support structure.



Inventors:
Vasey, Ian Andrew (Forster, AU)
Application Number:
11/760259
Publication Date:
12/13/2007
Filing Date:
06/08/2007
Primary Class:
Other Classes:
5/659
International Classes:
A47C21/02; A47C31/00
View Patent Images:
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Primary Examiner:
POLITO, NICHOLAS F
Attorney, Agent or Firm:
KING & SCHICKLI, PLLC (LEXINGTON, KY, US)
Claims:
1. Apparatus suitable for lifting a bed mattress, the apparatus comprising a carriage including a mattress support structure upon which a bed mattress can be carried and an elevating mechanism operatively connected to the mattress support structure for moving the support structure between a lowered and a raised position, the apparatus further including a bedding retention device operatively connected to the carriage so that when the mattress support structure is in the raised position, the bedding retention device is disposed at a lower position than the mattress support structure and in the lowered position it is caused to adopt a retention position as a result of relative movement between the bedding retention device and the mattress support structure.

2. Apparatus according to claim 1 wherein the retention device includes a platform operatively connected to the carriage for movement relative thereto and extending at least partially around the periphery of the support.

3. Apparatus according to claim 2 wherein the retention platform is suspended from the carriage so that in the raised position it is suspended in a lower position with respect to the support structure.

4. Apparatus according to claim 3 wherein the retention device is suspended from the support structure by straps.

5. Apparatus according to claim 4 wherein the retention device is generally annular in shape.

6. Apparatus according to claim 5 wherein the support structure includes a frame upon which the mattress can rest.

7. Apparatus according to claim 6 wherein the frame includes a generally planar peripheral frame section formed from one or more frame members.

8. Apparatus according to claim 7 wherein the frame is generally rectangular when viewed in plan and is dimensioned so that it is spaced inwardly from the sides of the mattress with which it is to be used.

9. Apparatus according to claim 8 wherein when the support structure is in the lowered position, it is nested within the retention device.

10. Apparatus according to claim 9 wherein the support structure and/or the weight carried thereby may be counter balanced by a counter balancing assembly.

11. Apparatus according to claim 10 wherein the counter balancing assembly includes one or more torsion bars or gas struts.

12. Apparatus according to claim 11 including a drive for moving the support structure between the lowered and raised positions.

13. Apparatus according to claim 12 wherein the elevating mechanism is arranged such that the support structure is adapted to be laterally displaced with respect to an upright axis in addition to being raised and lowered.

14. Apparatus according to claim 13 wherein the elevating mechanism includes a plurality of link members on opposite sides of the support structure each having one end portion pivotally mounted to the support structure and the other end portion thereof pivotally mounted to a base whereby pivotal movement of the link members causes movement of the support structure between the lowered and raised positions.

15. Apparatus according to claim 13 comprising a connector balancing assembly including at least one drum operatively connected between link members on each side of the support member and adapted for at least partial rotation when the links move between the lowered and raised positions, a flexible line one end being operatively connected to said drum and adapted to be wound therein, the flexible line being operatively connected to a spring device at its other end so that in the lowered position the spring device is tensioned.

16. Apparatus according to claim 14 wherein the base is part of the apparatus and includes a frame similar in configuration to the support frame and arranged so that in the lowered position the two frames are nested together.

Description:

FIELD OF THE INVENTION

This invention relates generally to apparatus for lifting a bed mattress. The invention finds particular application in the activity of bed making, although its application may extend beyond bed making to other activities such as, for example, the inspection, cleaning, airing and fumigation of mattresses of beds.

DESCRIPTION OF THE BACKGROUND ART

The typical height of a bed causes bed makers such as, for example, occupational bed makers in the hospitality industry to be prone to back injuries and other injuries. This is because of the continuous stooping required by the bed maker when making the bed. The injury risk is exacerbated by the requirement to lift the weight of the mattress to tuck the bedding under the sides and corners of the mattress. To try to alleviate this problem devices have been proposed to enable the mattress or whole bed to be raised to a suitable height during the bed making procedure. Such devices have generally suffered from being unduly complicated and have not overcome the problem of the bed maker still having to lift the weight of the mattress when tucking-in the bedding. Concerns also have been voiced by occupational bed makers about the risks and difficulties involved in locating used hypodermic syringes, used condoms and the like along the edges of the space between the mattress and the base of a bed during the bed making process. The devices which have been proposed to date do not overcome this problem.

It is therefore an object of the present invention to provide apparatus suitable for lifting a bed mattress which will alleviate one or more of the aforementioned problems.

SUMMARY OF THE PRESENT INVENTION

According to one aspect of the present invention there is provided an apparatus suitable for lifting a bed mattress, the apparatus comprising a carriage including a mattress support structure upon which a bed mattress can be carried and an elevating mechanism operatively connected to the mattress support structure for moving the mattress support structure between a lowered and a raised position, the apparatus further including a bedding retention device operatively connected to the carriage so that when the mattress support structure is in the raised position, the bedding retention device is disposed at a lower position than the mattress support structure, and in the lowered position it is caused to adopt a retention position as a result of relative movement between the bedding retention device and the mattress support structure.

When in use with the mattress support structure in the raised position and with a mattress carried thereon, the mattress is positioned at a height which reduces the risk of back injury to the bed maker by allowing the bed maker to make the bed without the need to stoop. With the mattress support structure in this raised position, the bedding retention device is disposed at a lower position relative to the mattress support structure so that there is an unobstructed gap between an underside of the mattress or support structure and an upper side of the bedding retention device. During the bed making procedure with the mattress support structure raised used bedding can be removed from the gap without the physical effort normally required to un-tuck the bedding in the process of removing it from the bed. The gap allows the region below the mattress to be visually inspected for hypodermic syringes, used condoms and other dangerous or contraband items without any need for the bed maker to touch the bed in any way. The edges of the fresh bedding can then be tucked in by loosely locating them within the open gap. This may be achieved without requiring any part of the mattress to be physically lifted by the bed maker. When the mattress support structure is returned to the lowered position the arrangement is such that relative movement between the mattress support structure and the bedding retention platform causes the gap to be closed, the edges of the bedding thereby being captured and held in place within the closed gap.

The bedding retention device may include a platform operatively connected to the carriage for the movement relative to the mattress support structure and extending at least partially around the periphery of the mattress support structure or beneath the periphery of the mattress support structure. The bedding retention platform may be of any suitable rigid or semi-rigid material such as plastics, metal, wood or the like, or it may consist of fabric or other flexible medium possibly stretched over a frame or other support. In one form the bedding retention platform is suspended from the mattress support structure so that when the apparatus is in the raised position the retention platform is suspended from the mattress support structure in a lower position with respect to the mattress support structure. When the apparatus is in the lowered position the mattress support structure may rest upon and/or nest within the bedding retention platform.

The support structure may have a peripheral edge and the retention platform may extend at least partially outwardly with respect to the peripheral edge. In one form the bedding retention platform may be generally annular in shape having an inner edge and an outer edge. It may for example at or near its inner edge closest to the centre of the bed be attached to or suspended from the mattress support structure by straps or other flexible means. These straps may be of fixed length, or they may be adjustable so as to vary the distance between the lower surface of the mattress and the upper surface of the bedding retention platform. In addition to or in the alternative to these straps, further straps or other flexible means may be attached to the bedding retention platform at or near its edge closest to the centre of the bed in order to differentially lower or raise the position of the bedding retention platform relative to the mattress support structure in the course of raising or lowering the mattress support structure. By this means the weight of the bedding retention platform may be used to counter-balance the weight of the mattress and the mattress support structure as the apparatus of the invention is raised or lowered. It will be appreciated that other forms of connection between the bedding retention platform and the carriage could be used. For example, links which pivotally connect to the frame and carriage could be provided. In another arrangement link assemblies compressing two or more links connected together for relative longitudinal movements could be used. Other arrangements could include springs or piston/cylinder devices.

In one form the mattress support structure may include a frame upon which the mattress can rest. The frame may include a generally planar peripheral frame section formed from one or more frame members. Preferably the frame is generally rectangular when viewed in plan and is dimensioned so that it is spaced inwardly from the sides of the mattress with which it is to be used.

The elevating mechanism may take any suitable form. For example, the elevating mechanism may be arranged such that the mattress support structure may be adapted to be laterally displaced with respect to an upright axis in addition to being raised and lowered preferably in the general direction between a bed head and a bed foot. In this particular form the elevating mechanism may include a plurality of link members on opposite sides of the mattress support structure each having one end portion pivotally mounted to the mattress support structure and the other end portion thereof pivotally mounted to a base whereby pivotal movement of the link members causes movement of the mattress support structure between the lowered and raised positions. In this embodiment the link members are caused to operate as a parallel link mechanism which causes not only upwards and downwards movement of the mattress support structure but also lateral movement. The base may be part of the apparatus and may include a frame or other structure similar in configuration to the mattress support structure and arranged so that in the lowered position the two structures are nested together or the mattress support structure rests wholly or partly upon the base, or alternatively the base may be a dedicated part of the structure of the bed base and/or may be housed partly or wholly within the bed base.

The mattress support structure and the elevating mechanism may be generally housed within a space at the centre of the bedding retention platform. They remain in place under the mattress at all times. With the apparatus in its folded or lowered position, only the edge of the bedding retention platform is visible between the mattress and the bed base.

When the elevating mechanism is deployed, the mattress support structure and the weight carried thereby are raised relative to the bed base. In order to relieve the bed maker of the physical strain involved in raising the mattress support structure, at least part of the weight of the mattress support structure and/or the weight carried thereby may be counter-balanced by a counter-balancing assembly. The counter-balancing assembly may include one or more springs, torsion bars, suspended weights or gas struts. Drive means may be provided additionally or alternatively for moving the mattress support structure between the lowered and raised positions.

In one embodiment the counter-balancing assembly may consist of a rigid cylinder forming the drum of a windlass. The drum may be incorporated into the base of the mattress lifting apparatus. The drum is allowed to rotate around its longitudinal axis of symmetry on an axle or pivot pins. Two parallel arms are welded or otherwise attached to the drum, one at each end thereof and perpendicular to the longitudinal axis thereof. Low-stretch flexible media for example cord or wire are wound around the circumference of the drum and then connected to one or more extension springs fixed into the base of the apparatus. The upper ends of the parallel arms are operationally attached by pivot pins to the mattress support structure, the arms constituting links in the system of parallel links in the elevating mechanism. With the mattress support structure in the elevated position the tension in the extension springs is relatively low. As the mattress support structure is lowered under the weight of the mattress and the mattress support structure itself, the movement of the parallel links connected to each end of the drum causes the drum to rotate about its longitudinal axis. This rotation winds the cord onto the drum, which in turn causes an increase in the tension in the extension springs. The increased tension creates an increasing resistance to the lowering of the mattress support structure and partly or wholly counter balances the weight of the mattress and the mattress support structure. With the mattress support structure in its fully lowered position the tension in the extension springs is at its greatest, and tends to lift the mattress support structure and the mattress sitting thereon.

To lift and counter balance heavier mattresses and/or bedding, more extension springs may be added to the system. In order to minimise the lateral forces exerted upon the drum of the windlass, two identical banks of springs may be used, one at each side of the drum. Fine adjustment of the spring tension in the system may be achieved by the use of a single turnbuckle or screw adjuster at the point where each bank of extension springs is connected to the frame of the apparatus.

The action of the springs or weights can be augmented or replaced with one or more motor drives similarly linked to the drum or otherwise linked directly or indirectly to the mattress support structure, or by one or more gas struts linked directly or indirectly thereto, or by one or more springs or other stored energy devices otherwise linked directly or indirectly to the mattress support structure.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention will hereinafter be described with reference to the accompanying drawings and in those drawings:

FIG. 1 is a schematic plan view of the apparatus according to one embodiment of the invention in an installed position on a bed base and in the lowered position;

FIG. 2 is a schematic side elevation of the apparatus in FIG. 1 with a mattress supported thereon;

FIG. 3 is a schematic plan view of the apparatus in FIG. 1 but in the raised or elevated position;

FIG. 4 is a schematic side elevation of the apparatus in FIG. 2 in the raised or elevated position;

FIG. 5 is a schematic end elevation of the apparatus in the position shown in FIG. 2;

FIG. 6 is a schematic end elevation of the apparatus in the position shown in FIG. 4;

FIG. 7 is detail taken from FIG. 4; and

FIGS. 8a, 8b and 8c are schematic representations of the lifting mechanism of the apparatus according to one embodiment of the invention

DETAILED DESCRIPTION INCLUDING BEST MODE

Referring to the drawings, there is shown an apparatus suitable for raising a bed mattress for a bed. In the form shown the bed comprises a bed base 52 and a mattress 54. The apparatus generally indicated at 10 in FIGS. 4 and 6 comprises a carriage 11 which includes a mattress support structure 12 in the form of a generally planar peripheral frame section 13 upon which a mattress 54 can be carried. The frame section is generally rectangular in shape when viewed in plan and can be formed by one or more frame members. As is best illustrated in FIGS. 4 and 6 the peripheral frame section is dimensioned so that it is spaced inwardly from the sides of the mattress 54. The carriage 11 further includes an elevating mechanism 20 which enables the mattress support structure to be moved from a lowered position (FIGS. 1, 2 and 5) to a raised position (FIGS. 3, 4 and 6). The elevating mechanism in the form illustrated includes two groups of largely parallel links 21, 23, 25 and 22, 24, 26, each link having one end pivotally connected to respective opposite sides of the frame section 13 by pivot pins 28.

The other end of each parallel link is pivotally connected to a base 30 by pivot pins 29. The base 30 is in the form of a generally planar frame section 32. In the form illustrated, the frame section 32 may rest in or be retained within a purpose-built housing or void 53 in the top of the bed base 52. In the form illustrated, parallel links 21 and 22 are interconnected by a rigid cross member 31. Thus rigid cross member 31 presents the base of a rigid u-shaped frame or section and parallel links 21 and 22 present the parallel arms thereof. Rigid cross member 31 lies along the axis of pivot for parallel links 21 and 22 at the point where they are pivotally connected to the base frame section 32. Similarly, parallel links 23 and 24 are interconnected by a rigid cross member 32, and parallel links 25 and 26 are interconnected to a rigid cross member 33.

It can be readily seen from FIGS. 4 and 6 that when the mattress support structure 12 is moved from the lowered position to the raised position, not only is it displaced upwardly but also it is laterally displaced towards one end of the bed base 52.

The mattress support structure can be manually operated or driven by a suitable drive. An elevating or counter balancing arrangement may be provided to at least partially elevate or counter balance the weight of the mattress 54 when moving the mattress support structure 12 and the mattress carried thereby from the lowered position to the raised position. The elevating or counter balancing device may be in the form of stored energy devices such as torsion bars, gas struts, springs, weights, elastic connectors or the like. For example, in the variant illustrated at FIGS. 8a, 8b and 8c, a rigid cylinder 80 has been substituted for cross member 32 connecting parallel links 23 and 24. Fixed to the cylinder 80 is low-stretch cord 81, 82, the free ends of which are respectively tied to one or more extension springs 83, 84 situated in two banks, on either side of the cylinder. The far end of each extension spring is secured to the base frame section 32. Lowering the mattress support structure 13 from the raised position imparts motion to parallel links 23 and 24 which act in relation to the cylinder as the handles of a windlass. As the mattress support structure 13 is lowered, the cord is wound onto the cylinder which acts as the drum of a windlass, creating increasing tension in the extension springs. With the apparatus fully lowered this spring tension is at its maximum and the tension in the extension springs tends to unwind cord from the cylinder, thereby tending to raise the ends of parallel links 23 and 24 and thereby also tending to raise the mattress support structure which is pivotally attached thereto.

It will be appreciated that other forms of elevating or counter balancing mechanism may be provided to elevate or counter balance the mattress support structure, and any form of counter balance or motive power can be used to actuate or assist in this task. The use of parallel links as described herein may be undesirable if the lateral displacement of the mattress is impeded for example by a footboard which is attached to the bed base, in which case it may be necessary to instead use an alternative mechanism which will raise the mattress support platform and mattress generally vertically without lateral displacement, or which will cause such displacement to be delayed until a bed footboard for example is cleared by the lower surface of the platform.

The apparatus 10 further includes a bedding retention platform 40 which in the form illustrated includes a generally planar platform 42 which may be of annular shape and which is operationally connected to and extends around the frame section 13 and/or the elevating mechanism. As best illustrated in FIGS. 1, 4 and 5 the inner edge of the platform 42 is disposed generally adjacent to the frame section 13, and the platform 42 extends outwardly therefrom, with its outer edge terminating in the region of the edges of the mattress with which it is used.

The platform 42 is operatively connected to the frame 13 so that when the frame 13 is in the raised position the platform 42 is disposed in a horizontal plane spaced below the horizontal plane of the frame 13. When in the lowered position the frame 13 is nested substantially within the internal space of the platform 42 so that both of the integers lie in substantially the same plane. Thus in one form the apparatus when in the lowered position appears from the edge of the bed as a substantially flat layer for example about 25 mm in height separating the bed base and mattress with which it is to be used. In this form the base frame section 32 is housed wholly or largely within the rectangular prismatic volume of the bed base, and is not visible from the outside of the bed with the apparatus in the lowered position.

As best illustrated in FIGS. 4, 6 and 7 the platform 42 is operatively connected to the frame 13 by a plurality of straps 46 arranged so that when the frame 13 is in the raised position the platform 42 is suspended on the straps therefrom below the plane of the frame section 13. This provides a gap 18 between the underside of the mattress 54 and the upper side of the platform 42 (FIG. 4). When the platform returns to its lowered position the frame 13 and the connecting straps 46 nest wholly within the platform.

The connecting straps 46 may be fixed or adjustable. In one preferred form the apparatus may be so arranged as to result in the effective length of the supporting straps 46 being gradually reduced or increased during the operation of lowering or raising the mattress support structure. This would have the effect of gradually reducing the separation between the respective planes of the bedding retention platform and the mattress support structure during the lowering process and, conversely, gradually increasing the separation between the respective planes of the bedding retention platform and the mattress support structure during the process of raising the mattress support structure. This gradual increase or decrease in separation could be achieved, for example, by harnessing the gradual lateral displacement of the mattress support structure as it is lowered from its raised position. The benefits of such an arrangement could include, for example, providing an extra counter balancing element to reduce the physical effort involved in raising and lowering of the mattress support structure, increasing the general degree of friction in the apparatus so as to improve the smoothness of activation and operation of the apparatus, and leaving a clear path for the closing of any catch between the mattress support structure and the base frame section 32 at the lowest position of operation.

It will be appreciated that the gradual increase or decrease in separation of the respective planes of the bedding retention platform and the mattress support structure may be alternatively achieved by means other than the shortening of the supporting straps 46. For example, separate cords, wires or levers might be used to achieve the same result, or the bedding retention platform might be suspended from the parallel links 21, 22, 23, 24, 25, 25 rather than from the mattress support structure.

In the form illustrated, and as is best illustrated in FIG. 7, the ends of two or more opposing parallel links, for example links 25 and 26, are offset for a relatively small distance approximately perpendicular to the longitudinal axis of the link at the point of pivotal connection of the link to the frame section 13, to present the general shape of a bladed gold club or hockey stick, so as to prevent the parallel links from coming into contact with the bedding retention platform and interfering with the disposition thereof during the lowering process. Each offset link is pivotally connected to the frame section 13 at a point close to the extremity of the offset section 70 of the link.

With the apparatus in the lowered or folded aspect, the mattress when in use by one or more occupants of the bed may be supported by one or more of the mattress support structure, the bedding retention platform, slats or other forms of support fixed between the opposing parallel links of the elevating mechanism, and slats, ribs, fins or other forms of support protruding in a generally upwardly direction from the base of the apparatus or the bed base and through, within or around the elements of the elevating mechanism within the void in the bedding retention platform.

It will be appreciated from the foregoing that the apparatus of the invention provides benefit to occupational bed makers, as well as to householders who experience difficulty in bed making due to age, infirmity or injury.

Elevating the mattress to a safe and comfortable height permits the bed maker to work with an upright stance, thereby reducing the loads and forces normally imparted to the spine, joints and ligaments of the bed maker during the bed making process. In particular the apparatus also enables the bed maker to tuck-in sheets and other bedding whilst the mattress is elevated without the need to physically lift the edges or corners of the mattress in order to do so, thereby further reducing such physical loads. In the preferred embodiment which enables the mattress to be displaced from the headboard or wall, the bed maker is provided with access to the head of the mattress without having to physically move the bed from the wall, thereby further reducing such loads.

The invention also allows for the non-tactile inspection of the region underneath the mattress, and particularly underneath the edges of the mattress, for objects such as discarded hypodermic syringes and condoms. It may also provide clear and easy access to the underside of the mattress, and to the top surface of the bed foundation or base, for airing and fumigation purposes.

The invention can be easily configured for building into new bed bases/foundations at the point of manufacture with only minimal impact upon the aesthetics or height of the bed. In another configuration it may be easily retro-fitted to most existing beds without major impact upon the aesthetics or height of the bed. In either configuration the bed base or foundation remains resting upon the floor at all times. During the bed making procedure the mattress, the mattress support platform and the bedding retention platform are elevated such that the upper surface of the mattress is raised about 400 mm above its normal position. At all other times the device rests unobtrusively beneath the mattress and inside the bed base until it is deployed by the bed maker. The mattress support platform, the lifting mechanism and the base frame are normally completely encapsulated within the space at the centre of the bedding retention platform and/or within a housing or void within the bed base, and become visible only when the apparatus is extended for bed-making purposes. In commercial or appropriate domestic situations a safety lock may be provided which prevents the accidental activation of the device once folded. A key or the like may be used to unlock the device.

As described above, the bedding retention platform is positioned below the mattress support structure when the apparatus is deployed. For example it may be separated from it by a gap of up to about 100 mm, which can open up when the apparatus is deployed and which can be adjusted if required. Conventional sheets and other bedding can be loosely tucked into this open gap without the need to lift any part of the mattress. In the embodiment described the bedding retention platform is supported from or near its inner edge only, so there are no straps, struts or other supports blocking access to the gap for the purpose of tucking-in bedding. The sheets and bedding can therefore be tucked-in all the way around the mattress without impediment, and they can be tucked conventionally or mitred as desired. The gap into which the bedding has been loosely tucked completely closes up as the mattress is lowered back to its folded position. The sheets and bedding are then held in place only by the normal weight of the mattress as it comes to rest on the bedding retention platform. In this way the degree of “capture” of the tucked-in bedding feels natural to a user of the bed, and the sheets and bedding are held in place in the same way as they would have been if the bed had been made-up by conventional means. Indeed, the bed can still be made up by conventional means if this is desired.

The apparatus of the invention can utilise existing conventional bedding. No special sheets or fastenings or other forms of bedding are required. There is no need to attach the bedding to any clips, clamps, frame or other structure or device prior to making the bed. The separation between the edges of the mattress and the bedding retention platform when elevated also greatly simplifies the process of attaching and removing conventional mattress protectors, fitted undersheets and the like. The mattress sits upon the apparatus under its own weight and need not be attached to any part of the apparatus. It can be turned and rotated in the normal way with the device in the folded position.

The reference in this specification to any prior publication (or information derived from it) or to any matter which is know, is not and should not be taken as an acknowledgment or admission or any form of suggestion that the prior publications (or information derived from it) or known matter forms a part of the common general knowledge in the field of endeavour to which this specification relates.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

Finally, it is to be understood that various alterations, modifications and/or additions may be incorporated into the various constructions and arrangements of parts without departing from the spirit or ambit of the invention.