AU2002301101B2 - Elevating Bed - Google Patents

Description

Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

(ORIGINAL)

Name of Applicant: HUGH KELLY Actual Inventor(s): HUGH KELLY Address for Service: SANDERCOCK COWIE 69 ROBINSON STREET DANDENONG VIC 3175 Invention Title: ELEVATING BED Details of Associated Provisional Application(s): No(s): Australian Provisional Application No. PR7829 Filed: 19 t h September, 2001.

The following statement is a full description of this invention, including the best method of performing it known to me: -1- 2002-09-19.A:\406maxicare.fle.wpd, I la- TITLE: ELEVATING BED FIELD OF THE INVENTION This invention concerns patients beds of adjustable height.

BACKGROUND OF THE INVENTION Hospitals and nursing homes devote increasing care to aging populations. In aging Copyright. All rights reserved.

C Sandercock Cowie 2002-09-19.A:404maxicare.complee.wpd, I patients, dementia, confusion and behaviour modified by medication, means that even simple operations such as transferring patients in and out of bed brings some risks.

Injury from falling out of bed is not uncommon when non-elevating beds are used. This risk is reduced by introducing beds which rise and fall so that the patient can sleep close to the floor. When the patient is ready to stand up, the bed is raised so that the patient can be seated in the bed with their feet on the floor. Further raising assists the patient to stand. Their bed movements must be controlled by staff who use bed movement in combination with chairs, trolleys, patient lifters and other ancillary equipment which avoids the need for the nursing staff to lift the patient. The bed movement at or close to floor level is crucial to cooperating with such equipment. The carriages of the equipment must underlie the bed frame during patient transfer and accordingly the bed frame thickness must be minimised because to this thickness must be added the mattress thickness. Such mattresses commonly have a concave upper face to centralise the patient and to act as a gravity barrier to falling out of bed.

Mattress contouring was introduced to replace the use of cot type restraints which breached operating protocols concerning the freedom of the patient.

SUMMARY OF THE INVENTION The apparatus aspect of the invention provides a patients' bed of adjustable height comprising a rise and fall bed frame supported between two ends, wherein the rise and fall of each end of the frame is controlled by a motor or an equivalent, wherein the mattress tray is capable of descending floor.

Patients may spend their sleeping hours at a height equal to the thickness of the mattress plus the thickness of the bed frame.

The ends have frame guides which allow the frame to rise and fall parallel to the ground.

The frame may have a mattress support capable of inclination to allow passage of the bed through a door.

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SSandercock Cowie 2002-09-19.A:\404maxicar.completc.wpd.2 The end may have vertical guides along which the ends of a cross bar rise and fall. The ends may support a motor mount, and a motor may drive a screw which engages a nut on the cross bar.

Preferably the motors are controlled for both synchronous rise and fall of the bed frame and asynchronous rise and fall so that the patient can be rested at a desired inclination to assist blood flow.

The motors may be supplied from a 24v dc power pack with means to vary the quantity of current proportionate to the load. The frame may be detachable from the ends for freight convenience.

In an alternative version there may be a motor at each comer of the bed. In such an arrangement the motors in each may work as pairs. The frame may be generally planar with a mattress tray. Conveniently, and in accordance with established practice, the tray may be hinged between the ends so that the patients torso can be raised. This is achieved by a ram fixed at the frame beneath the mattress tray.

BRIEF DESCRIPTION OF THE VIEWS OF THE DRAWINGS One embodiment of the invention is now described by way of example with reference to the drawings in which:- Figure 1 is an end view of the bed.

Figure 2 is an exploded view of an end of the bed.

Figure 3 is analagous to Figure 2.

Figure 4 is a side elevation of the bed showing normal and lowered positions.

Figure 5 shows the geometry of the bed when tilted to the maximum.

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(0 Sandercock Cowie 2002-09-1 9.A\404-idcxompkccwpd.3 DETAILED DESCRIPTION WITH RESPECT TO THE DRAWINGS Referring now to the drawings, the bed comprises a head end 2, a foot end 4 and a rise and fall mattress support 6. The ends are the same and consist of an internal upstanding rectangular frame 8 made of bolt together, flanged sheet steel styles 10 and rails 12.

Internal frame 8 supports an external frame made of C-shaped steel pillars 12 and beams 16. Feet 18 carry casters The internal frame supports a pair of square section hollow tubes 22 which act as linear motion guides for a pair of carriages 24 which ride up and down the guides. The carriages have wheels which roll on the front and rear faces of the tubes 22. The carriages each have a bracket 26 which project through slots 28 in a front panel (see Figure The panel extends from pillar to pillar and corresponds to rear panel 32.

The brackets 26 are L-section and support the bed frame 6. The carriages are linked by a cross member 34 which has a fabricated nut assembly 36. The cross member rises and falls between the top and bottom rail 12 and is driven by a screw 38. The screw has a buttress thread and is seated in a thrust bearing 40 located in the bottom rail 12. The screw has a square upper end (not shown) which projects into the socket of a worm and pinion gearbox 42 bolted to the top rail 12. 24v dc motor 44 is integral with the gearbox.

LINAKTM motors are supplied to the industry by the Swedish company of that name.

They incorporate reed switches (not shown) for sensing the resistance to the motor torque in order to vary the current appropriately from a power pack 46 supplied by mains current in the ward.

The cross member remains parallel to the floor. The mattress support 6 is bolted to brackets 26. Bearers 48 supports sheet metal mattress tray 50. The tray has hinge mounts 52 (see Figure The mattress tray has a leg section 54 and a torso section 56.

The latter is raisable by a ram 58 underneath the leg section. This ram is a standard feature of patients beds.

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Sandercock Cowie 2002-09-19.A:\404maxicare.complct.wpd,4 The power pack 46 supplies motors separately with current via a hand held control The switch for each motor allows an operator to impose an inclination on the bed frame at any height. It is possible for the top of the mattress tray to descend to 90mm above the floor. If a patient rolls off the mattress, injury is unlikely at this height. If a lifting carriage is wheeled up to the bed, the frame is raised to allow the carriage to project beneath. Thereafter the height can be adjusted in accordance with the size and mobility of the patient.

We have found the advantages of the above embodiments to be:- 1. Sleeping height may be very close to the floor precluding injury.

2. A variety of inclinations are possible, especially when a hinged mattress tray is used.

3. Simple construction and assembly techniques reduce the cost of manufacture.

In a non-illustrated version a pair of screw drives at both ends enable the patient to be tilted out of the bed onto a trolley.

It is to be understood that the word "comprising" as used throughout the specification is to be interpreted in its inclusive form, ie. use of the word "comprising" does not exclude the addition of other elements.

It is to be understood that various modifications of and/or additions to the invention can be made without departing from the basic nature of the invention. These modifications and/or additions are therefore considered to fall within the scope of the invention.

A fluid operated ram and a mechanical jack are examples of equivalents to the motor and screw.

Copyright. All rights reserved.

SSandercock Cowie 2002-o9-19,A:\4o4mxicare.complete.wp,S

Claims (9)

1. A patient's bed of adjustable height comprising rise and fall mattress support supported by two bed ends, each end having a static frame and a rise and fall cross member by which the mattress support is borne, a nut fixed to the cross member and a motor mounted to the bed end and coupled to a vertical screw which acts between the static frame and the nut, wherein the mattress tray is capable of descending close to the floor.

2. A patient's bed as claimed in Claim 1, wherein the screw reacts against a bearing in the static frame.

3. A patient's bed as claimed in Claim 1 or 2, wherein each bed end is a rectangular sub frame free to tilt on horizontal axis, whereby the ends remain at 900 to the mattress support at all inclinations of the mattress support.

4. A patient's bed as claimed in any one of Claims 1-3, wherein the mattress support is capable of inclinations about a horizontal longitudinal axis to allow passage of the bed through a door.

A patients bed as claimed in any one of Claims 1-4, wherein the motors are controllable for both synchronous and asynchronous rise and fall.

6. A patient's bed as claimed in any one of Claims 1-5, wherein the motors are dc motors with means to vary the current proportionately to the load.

7. A patient's bed as claimed in any one of Claims 1-6, wherein the mattress support is detachable from the bed ends.

8. A patient's bed as claimed in any one of the preceding claims, wherein the bed ends each have upright frame guides, each with a carriage free to ride between a Copyright. All rights reserved. Sandercock Cowie

2006-01-20,Z:\S pecifications\raxicare. complete amended. wpd,6 -7- high and low position and a cross member mutually connects the carriages, the mattress support being borne by the cross member.

9. A patient's bed as claimed in Claim 8, wherein each carriage has wheels which roll on opposed faces of the guides. A patient's bed as claimed in Claim 8 or 9, wherein the guides have a pair of parallel opposed faces and the carriage has wheels which run on the opposed faces. 11. A patient's bed as claimed in any one of Claims 8-10, wherein guides are square sectioned tubes. 12. A patient's bed as claimed in any one of Claims 8-11, wherein the carriages each have two mutually spaced pairs of wheels. 13. A patient's bed as claimed in any one of the preceding claims, wherein the mattress tray descends to 90mm above floor level. 14. A patient's bed as claimed in Claim 1, wherein the rise and fall of each end of the mattress support is controlled by a pair of motors. A patient's bed substantially as herein described with reference to and as illustrated in the accompanying drawings. Dated this 2 0 t h day of January, 2006. SANDERCOCK COWIE PATENT ATTORNEYS FOR HUGH KELLY Copyright. All rights reserved. (0 Sandercock Cowie 2006-01 -20,Z:\Specifications\maxicare complete.amended wpd,7