IE45533B1 - Improvements relating to seats and beds - Google Patents

Abstract

The bedding prevents soreness of patients caused by sitting or lying, in that the superficial elements (1, 2) forming the surface are cyclically height-adjustable. During each cycle, 25% of the superficial elements (1) are sunk at a lower level while the remaining 75% of elements (2) are in the initial position. The superficial elements are arranged such that each sunken element (1) is surrounded by six elements (2) at identical spacing between each other and the sunken element. The superficial elements (1, 2) are mounted on rods (I-IV) coupled to a drive motor. An equalisation system, for example communicating cylinders, ensures that the sum of spacings of the support surfaces of all the elements on a rod to the particular rod is constant.

Description

This invention relates to seats and beds» and is particularly concerned with a seat or bed, the surface of which is divided up into surface elements which are connected to movable support means in such a manner, that a proportion of the elements may be periodically moved downwards from an initial level to a lower level and then moved upwards back to the initial level, and this cycle repeated for the other elements in sequence.

Such seats or beds are used for persons who must constantly 10 be sitting or lying, e.g. on account of paralysis, and who are therefore prone to contracting seating-or bedsores, unless the attendant nursing personnel help the persons in question to change position at suitable intervals.

A known seat or bed of the type mentioned by way of 15 introduction is known from the Danish Patent No. 133,232, which deals with a seat or bed with surface elements arranged in a square pattern and mounted on parallel horizontal rods. The rods are arranged in two sets which alternate with one another, and each set may be moved up and down in a cycle. When either set is lowered, each lowered element is surrounded by four elements of the -2A 5533 other set at their initial level, with the result that insufficient sidewards movement takes place. The achieved massage effect is, therefore, insufficient to cause the desired circulation of the blood, which is a condition of the healing of seating-or bedsores.

Furthermore the surface pressure is proportionally high as 50% of the support will be removed by the lowering and the weight of the body is supported by the remaining support elements.

According to the present invention there is provided a seat or bed, the surface of which is divided up into individual surface elements which are arranged in rows with the elements in adjacent rows staggered and supported by movable support means such that every fourth row of elements may be moved periodically downwards from an initial level to a lower level and then moved back upwards to the initial level, this cycle being repeated sequentially for all the rows of elements, whereby each lowered element is surrounded by six elements at the initial level equally spaced on the circumference of a circle centred on the lowered element, the spacing between adjacent ones of the said six elements being equal to the radius of the circle.

Hereby it is achieved firstly that the surface pressure is -3” reduced, as only 25% of the support is lowered at any one time, whereby the remaining 75% will be able to bear the weight of the body. This means a relief to the sitting or lying person, in that the surface pressure only rises a little. Furthermore this positioning of the elements causes a considerably greater variation of the support pattern between the single lowerings, as 25% lowered are varied between the remaining 75%, so that there are three lowerings between each repeated initial cycle. This great TO variation means an essentially improved massage effect, such that persons with sores may be expected to be fully cured of sores when using this support.

Each row of elements is preferably mounted on a respective rod in such a manner that the distance of the elements from the rod can be varied continuously and in such a manner, that the sum of the distances of the elements on each rod from the rod remains substantially constant. This contributes to a hitherto unknown form of support, as each element in the initial position will now be able to yield to the user's body and will moreover equalize the surface pressure in such a manner that the body is supported completely uniformly all over the layer of surface elements. This equalizes the variations of surface pressures and will be felt as a great relief by the user, who does hereby become less stressed on particularly exposed parts of the body, which have in the hitherto known cases of supports had to take 4up a disproportionately large weight, resulting in ulceration.

The invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows part of a seat or bed in top view in two situations of support; Figure 2 is a partially sectioned side view of a rod with supporting elements.

The seat or bed shown in Figure 1 commprises individual supporting elements 1, 2 which are mounted on longitudinal or transverse rods I, II, III, IV which rods can be moved vertically in relation to an initial position with all the rods on the same level by a not shown driving means. This driving means moves the rods in such a manner that every fourth rod, e.g. all rods indicated by 1 in the left half cf Figure 1, are moved downwards in relation to the initial position, while the other rods remain on a common level, so that the elements 1, which are shown cross hatched, are lower than the elements 2. -545533 Hereby a pattern appears, which is formed by circles of six elements 2, which are centred ahout each lowered element 1, as indicated by dotted lines in Figure 1.

By raising the rods 1 and lowering e.g. the rods II, as in the right half of Figure 1, the pattern is moved both longitudinally and transversely. By subsequently lowering the rods III and thereafter lowering the rods IV, the support may thus be moved in a very regular and pleasant manner, which ensures the desired massage effect.

The driving means for lowering and raising the rods may be of any known type, such as a hydraulic with a piston and cylinder, a bellows arrangement, or a mechanical device, e.g. rocker arms or cam discs, or an electromagnetic device.

The spacing 3 between the individual elements 1, 2 is equal throughout, as indicated in Figure 1, whereby an event distribution of the points of support is achieved.

Referring to Figure 2, the individual elements 1, 2 consist of a cup-shaped bottom part 7, which is supported by a piston rod 4. In the bottom part 7 is located a resilient top part 8 which can consist of a closed ball-like body -6filled with air. The top part 8 is flatted at its top 9, in order that the elements 1, 2 can together form a generally flat surface of support, where each element can absorb a pressure all over the tops 9.

To ensure the desired equal distribution of the weight of the user's body on the elements 1 and 2, the rods IIV are hollow, liquid filled, and provided with a number of cylinders 6, which have respective pistons 5 each with a piston rod 4, to which the associated element 1, 2 is attached, Thus the tops of all the elements may lie initially at the same distance A from the rods with the piston 5 e.g. in the middle of the cylinder 6, and when the user lies or sits on the elements, they may move up and down relative to one another according to the weight distribution.

In order to ensure that the liquid does not leak out of the cylinders 6 round the pistons 5, there can for example be attached respective membranes e.g. of rubber to the inner sides of the cylinders, said membranes being impenetrable to liquid. Each membrane fits tightly to the under side of the piston and can follow the up and down going movement of the piston without hampering this movement. It is thus -7ensured that the system is completely liquid-tight and simultaneously that the piston can he moved freely up and down, as it is unnecessary to provide the piston with sealing rings such as 0-rings.

By a pressing down of some elements e.g. by a person being seated on the support, the liquid, which may preferably be oil, is pressed over into the other cylinders, and elements of which are hereby raised for contact with the body by virtue of the closed hydraulic system. Hereby a uniform weight of body is absorbed by the elements mounted on the same rod and the surface pressure is reduced to a hitherto unknown level. It has proved in practice that while with a body weight of 70 kg one is exposed to a surface pressure of approx. 35 g/cm in a sitting position, the surface pressure is by means of the invention reduced 2 to between 10 and 15 g/cm when the number of elements is between 500 and 600 in one seat.

In another embodiment each element consists of a stationary, yielding cylinder, a so-called roller membrane, which membrane can be filled with air ora liquid. In order to form a closed system, all membranes on one row, corresponding to the elements on a rod, are connected by means of e.g. a hose or a pipe. By letting the upper side of the membrane form the very support and stress the membrane by a pressing in, the upper side is raised to form an element in the 85533 initial position, while a removal of the stress will result in a lowering of the surface and thus of the element. Hereby is created a leakage-proof system of simple construction.

Claims (5)

1. WHAT WE CLAIM IS:1. A seat or bed, the surface of which is divided up into individual surface elements which are arranged in rows with the elements in adjacent rows staggered and supported by movable support means such that every fourth row of elements may be moved periodically downwards from an initial level to a lower level and then moved back upwards to the initial level, this cycle being repeated sequentially for all the rows of elements, whereby each lowered element is surrounded by six elements at the initial level equally spaced on the circumference of a circle centred on the lowered element, the spacing between adjacent ones of said six elements, being equal to the radius of the circle.

2. A seat or bed according to claim 1, wherein each row of surface elements is mounted on a respective rod which is connected to driving means for moving the rod.

3. A seat or bed according to claim 2, wherein -9the elements are mounted on each rod in such a manner that the distance of the elements from the rod can be varied continuously and in such a manner, that the sum of the distances of the elements on each rod from the 5 rod remains substantially constant.

4. A seat or bed according to claim 3, wherein each rod is hollow and each element is attached to a piston rod the piston of which slides in a cylinder on the rod, said cylinder being hydraulically connected with the other cylinders on the rod so as to form a closed hydraulic system.

5. A seat or bed substantially as herein described with reference to the accompanying drawings.