Pressure relief cushions

Abstract: The cushion comprises a relatively rigid carrier 10 to which is secured at least one flexible layers 13 to form a sleeve. Each such sleeve receives a liquid or gel-filled cell which comprises a flexible layer 17 secured to a backing layer 16. Opposite ends of the backing 16 preferably project from opposite ends of the sleeve, with the projecting ends being releasably secured to the carrier 10.

Description: TECHNICAL FIELD OF THE INVENTION This invention relates to pressure relief cushions for supporting part of the body. BACKGROUND Such cushions are of particular value in the prevention of pressure sores in people such as the disabled or geriatric, who are obliged to remain in one position for long periods of time. US Patent No. 4 391 466 and European Patent No. 0 284 294 disclose known forms of chair which incorporate pressure relief cushions. An aim of the present invention is to provide a from of pressure relief cushion which is patentably different from existing cushions. SUMMARY OF THE INVENTION The present invention proposes a pressure relief cushion as set forth in the appended Claims. BRIEF DESCRIPTION OF THE DRAWINGS The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings: Figure 1 is a general exploded view of part of a water chair, including two cushions of the invention, Figure 2 is a general view of a water cell for use with the chair of Fig. 1, Figure 3 is a transverse section through the water cell as used in an upright cushion, Figure 4 is a general view of an alternative form of seat cushion for the water chair of Fig. 1, and Figure 5 is a general view of a cushion of the invention as incorporated in a divan. DETAILED DESCRIPTION OF THE DRAWINGS Referring firstly to Fig. 1, the water chair comprises a generally horizontal seat portion 1 and an upright back-rest portion 2. Each portion 1, 2 is provided with a support cushion 3, 4 respectively. Each support cushion includes a planar carrier 10 of relatively rigid plastics sheet which is secured to the frame of the chair by nails 11, staples or the like. It will be appreciated that the carrier could also be of hardboard, plywood or other stiff sheet material. A series of horizontally extending sleeves 12, extending from side-to-side of the chair, are formed from a flexible sheet 13 of cotton, gabardine, canvas or like material, which is secured to the carrier 10 by a series of parallel rows 14 of stitching, staples or similar means. The width of the strips of the sheet 13 defined between the rows of stitching 14 is greater that the linear distance between the rows 14, so that the sleeves can each receive a respective elongate cell 15, one of which will now be described with reference to Fig. 2. Each cell 15 comprises a backing sheet 16 of relatively rigid water-impermeable plastics such as pvc, to which a front body-support sheet 17 of relatively flexible pvc or other water-impermeable plastics is secured by heat welding 18 around the periphery of the sheet 17. The support sheet 17 is either pre-shaped and/or is sufficiently flexible to form an internal space between the sheets 16 and 17 which is partially pre-filled with water prior to sealing the cell. The space is generally filled to between 65% and 98% of its maximum volumetric capacity depending on the application and position of use of the cell. Each cell 15 is slid longitudinally into one end of the respective sleeve 12. The transverse width of each backing sheet is slightly less than the distance between the lines of stitching 14, and the width of the flexible front sheet of the sleeve 12 is dimensioned to hold the cell against lateral movement. Longitudinal movement of the cell may be prevented by providing end portions 20 of the backing sheet 16 which project from each end of the sleeve 12 and are releasably secured to the carrier 10 by press-studs 21, hook-and-loop fasteners or the like. In the case of the cushion 4, which is disposed in an upright, rearwardly inclined position in use, the backing sheet 16 provides integral support for the cell 15 which helps to maintain the shape of the cell as shown in Fig. 3. The cell thus has a less pendulous shape in transverse section than has hitherto been possible for a cell of similar dimensions and filled capacity. The cells are easily removed when required by releasing the fasteners 21 and sliding the cells out of the sleeves 12, and the rigid backing sheet 16 allows the cells to be easily re-inserted. This is very important to allow thorough cleaning. In practice, the cushions will usually have a decorative further outer covering of cotton or the like. It will be appreciated that the sheets 16 and 17 could be secured by means other than heat welding, such as by using a suitable adhesive for example. Also within the scope of the present invention, the rear wall of the cell could be formed by a rear panel of flexible sheet material bonded to an outer layer of stiff board. The rear wall could also be formed of two superimposed panels of flexible sheet with a sheet of stiff board sandwiched between them. Instead of water, the cell could be partially filled with another liquid or a viscous gel. The cell could furthermore be provided with a valve or a capped opening 24 (Fig. 2) to permit drainage and refilling of the cell. This would also allow the volumetric contents of the cell to be adjusted after filling, if desired. In the case of a generally horizontal cushion, as used with the seat portion 1, the cells 15 and sleeves 12 could run from front-to-back of the chair if desired, as shown in Fig. 4. The carrier 10 could also be curved as in the case of the divan illustrated in Fig. 5. It will also be appreciated that the cushion could form a separate entity which can be placed on a conventional seat, bed or the like. The backing portion 16 provides integral support for the cell, which determines the shape of the cell to a large extent whilst still permitting the body-support portion 17 to conform to the shape of the human body. The carrier may be secured to or form part of the back or seat of a multi-seater chair such as a settee. The cushion could also form the support surface of a bed.

Claims: A pressure relief cushion comprising a substantially rigid carrier (10) and at least one relatively flexible layer (13) secured thereto to form a sleeve, the or each sleeve having a cell (15) inserted therein which comprises an envelope partially filled with a liquid or gel, said envelope including a body-support portion (17) and a backing portion (16), characterised in that the cell (15) is provided with attachment portions (20) at opposite ends of the backing portion (16), said attachment portions projecting from opposite ends of the sleeve (10, 13) and both being releasably secured to the carrier (10) such that the backing portion (16) is held rigid against the carrier (10) but the body-support portion (17) is relatively free to change shape. A pressure relief cushion according to Claim 1, in which said attachment portions (20) are releasably secured to the carrier (10) by hook-and-loop fasteners.

Inventors: CAREFLEX LIMITED
Applicants: CAREFLEX LTD, CAREFLEX LIMITED
Application year: 1995
Main classification: A47C4
IPC codes: A47C27, A61G7, A47C4