EP1740080A1 - Device particularly for toilet seats for water closet - Google Patents

Abstract

A cushioning device suitable for the manufacture of toilet seats, comprising a sheet (3) of an elastomeric gelatinous material which is completely covered by a film (4) of a resilient polymeric material that constraints its periphery, wherein said sheet has a minimum thickness of 2cm; and a toilet seat (1) comprising a lower rigid member (5) and an upper cushioning device as defined; and the use of an elastomeric gelatinous material for the manufacture of a toilet seat (1) as defined above, where the toilet seat prevents a decubitus-like effect consisting of the paraesthesia of lower limbs and its correlated injuries, in a subject resting on it.

Description

DEVICE PARTICULARLY FOR TOILET SEATS FOR WATER CLOSET Technical Field The present invention relates to a cushioning device suitable for toilet seats for sanitary. More in particular, the present invention relates to a cushioning device which can be advantageously used for the manufacture of a toilet seat for preventing paraesthesia of lower limbs due, for example, to prolonged sitting of a subject on a toilet seat. Background Art In the prior art, there have been numerous attempts to provide cushioning devices such as pads which provide proper positioning and stabilisation of a human body on a rigid surface by eliminating peak pressure areas and by evenly distributing the pressure force of said body over a broad surface area. Among the relevant prior art there are foam, fluid and gel cushions. In general, the foam cushions show the significant problem that protruding portions of the object being cushioned (such as a body) are placed under the highest pressure due to the foam spring-like behaviour, resulting in pressure on the cushioned object not being equalized. The cushion devices which use some type of a flowable fluid (such as liquid, air, gas, emulsion, lubricated objects or particles, etc.) suffer with a number of problems. For example, when the cushioned body is shifted or repositioned on the fluid cushion, instability may result; due to the necessity of maintaining a fluid-tight bladder, fluid cushions may be unreliable due to the possibility of bladder puncture; if a fluid cushion is not of sufficient thickness, the resting body being cushioned may displace enough of the cushioning fluid to bottom out against a base on which the fluid bladder is resting, resulting in little or no cushioning effect; finally fluid cushions have little shape memory. The cushion devices which rely on conventional non-specific gelatinous materials have limited compressibility and therefore do not permit the cushioned object to sink deep into the gel. As a result, only a small surface area of the cushioned object is cushioned by a prior art gel cushion, resulting in a greater supporting force being applied on that small surface area than would be applied if a greater surface area of the cushioned object were to contact the gel cushion for support. Irrespective of the type of material used for the device, no cushioning device has ever been applied to toilet seats. However, such an application would be highly desirable since the conventional toilet seats are rigid and are not suitable to distribute the weight of a human body resting on them. Upon a prolonged sitting on the toilet seat, this condition may lead to a decubitus- like effect consisting of the paraesthesia of lower limbs due to an excessive pressure on nerves and vessels of the rear part of legs and thighs. In old people or obese subjects as well as in those who suffer with invalidating pathologies to lower limbs, even a mild form of paraesthesia may result in severe straining, fractures, or dislocations. Disclosure of the invention The aim of the invention is to provide a cushioning device, particularly suitable for the manufacture of toilet seats for water closet, that overcomes the above drawbacks. It is an object of the invention to provide a cushioning device as defined above that effectively prevents pressure peaks, that maximizes the surface area of the resting body that is in contact with it, that does not lose its structural integrity or cushioning effect if punctured, that has shape memory, that shows cushioning protection to a cushioned body or part thereof even if the body has bottomed out within the cushion, that has a great range of compressibility. It is another object of the invention to provide a toilet seat for water closet comprising the cushioning device as above, that even upon a prolonged resting of a subject on the seat, prevents the decubitus-like effect consisting of the paraesthesia of lower limbs and its dangerous correlated injuries. These and other objects are achieved by a cushioning device as defined in claim 1. These and other objects are achieved by a toilet seat as defined in claim 2. These and other objects are also achieved by the use of an elastomeric gelatinous material as defined in claim 3. Brief description of the drawings These and other objects will become apparent to those skilled in the art upon reading the specification in conjunction with the accompanying drawings wherein: FIG. 1 depicts a perspective view of a water closet having a toilet seat, according to an embodiment of the present invention, mounted on it. FIG. 2 depicts a cross sectional view of a portion of the toilet seat of figure 1, wherein the cross section is made according to line II-II of figure 1. FIG. 3 depicts a sectional broken-away view of a water closet on which a toilet seat of the invention is mounted. FIG. 4 depicts a side view of a water closet, having a conventional cover and a toilet seat, according to an embodiment of the invention, mounted on the water closet and pivoted to the cover by means of hinges. FIG. 5 depicts a perspective view of a water closet having a toilet seat, according to an embodiment of the present invention, mounted on it. FIG. 6 depicts a cross sectional view of a portion of the toilet seat of figure 5, wherein the cross section is made according to line VI- VI of figure 5.

Ways of carrying out the Invention The cushioning device of the invention comprises, preferably consists of, a sheet of an elastomeric, gelatinous material 3 and is totally covered by resilient polymeric film 4 that constraints its periphery. The elastomeric, gelatinous material is latex-free and glass-fibre free, antistatic, has shape memory even after repeated use, is water-repellent, has no fluid or odour absorption, is non inflammable and fire-rated as self extinguishing, is easy to be cleaned, it can be decontaminated by routine techniques, and is fungus and bacterial resistant. Suitable elastomeric, gelatinous materials displaying the required properties are well-known per se. An example of a suitable marketed gelatinous material is a silicone or silicone derivative combined with any hypoallergenic adhesive conventionally used in the medical field for the manufacture of objects which come into direct contact with human or animal bodies. Examples of suitable gel materials to carry out the invention are the gels marketed under the trade name PurGel®, Oasis® or Oasis elite® and Xcelgel™, by Gaymar Inc., Trulife and PCI Inc., respectively. The skilled person in the field being told of the properties listed above would immediately and unambiguously identify other suitable gelatinous materials by using his common general knowledge or by means of routine tests. The same holds for the silicone or silicone derivatives as well as the hypoallergenic adhesives and the their respective amounts to be mixed. It is essential that the sheet of gel material be at least 2cm thick. In a preferred embodiment the thickness of the sheet may vary along the device depending on the pressure that will rest on the different portions of the device. In a preferred embodiment, the minimum thickness (at least 2cm) will correspond to the rear part of the device 8, i.e. the one which is the closest to the pivoting point to the water closet, while the maximum thickness will correspond to the front part of the device 9. The surface of the gelatinous material may have any desired appearance. The shape may be uniform, planar or corrugated and, if desired, it may be coloured. The sheet of gelatinous material is totally covered by a film 4 of a resilient polymeric material such as a conventional polyurethane film. The covering film can be made up of any resilient material provided that it displays at least the same advantageous properties listed above for the gel with respect to water-repellence, resistance to biological contaminants, and decontamination and cleaning easiness, preferably it displays all the properties listed above for the gel. The choice of a resilient material for the covering film is important to the extent that it reduces the risk of damages (such as the puncture) to the covering that could cause leaking of the inner gel material. Nevertheless, since the gel material is also auto-sealing, such risk is further reduced. The outstanding properties of the gel combined with the resiliency of the film have proved to provide a sufficient compressibility and strength to effectively accommodate a wide range of weights such as in the case of obese subjects. The device of the invention may be provided as such or, as discussed in detail below, it can already be provided in combination with any rigid support 5 such as a conventional toilet seat. In any embodiment of the invention, the shape of the cushioning device is substantially U-shaped so that it substantially overlaps with, and fits to the rigid member. Thus, even in the embodiment wherein the cushioning device is provided as such, it can be easily adapted to any conventional rigid toilet seat directly by the final user. In a further aspect the present invention provides a toilet seat 1 suitable for water closet, wherein said toilet seat comprises, preferably consists of, a lower rigid member 5 joined to an upper cushioning device 3 and 4 as defined above. By "lower" and "upper" when referred to the reciprocal position of the rigid member and the cushioning device, it is intended that the rigid, supporting member 5 is positioned under the cushioning device 3 and 4 and the skin and tissues of the subject resting on the toilet seat come in contact mostly, preferably exclusively, with the cushioning device. The rigid member 5 may be any conventional toilet seat. Said member can be made of any rigid suitable material known in the field such as plastics, wood, metals or combinations thereof. Said first member is substantially U-shaped, like a conventional toilet seat, and contains means 7 for pivoting to a water closet 2 and a water closet cover 6 (which in Figure 4 is depicted in both an open-position 6 and in a closed-position 6'). Suitable pivoting means 7 are, for example, conventional hinges. In the event that the cushioning device is slightly larger than the rigid supporting member, thus requiring larger toilet covers, conventional hinges can optionally be adapted so as to be suitable for larger toilet covers. The rigid member is joined to the cushioning device through its upper surface. As said, both the rigid member and the cushioning device are roughly U-shaped so that in the preferred embodiment they substantially overlap. Nevertheless, the outstanding advantages of the cushioning device are present even though it is slightly larger or narrower than the rigid member. As said, the cushioning device can be provided as such, i.e. as a sheet of gelatinous material 3 wrapped in a film 4 of a resilient material as defined above, wherein the combination with a conventional toilet seat can be made by a final user. According to this embodiment (Figures 5 and 6), the device can be joined to any conventional toilet seat for example by means of a bi- adhesive tape 8 or any adhesive composition. The bi-adhesive tape 8 is preferred because it entails a better flexibility of the device since it allows an easier adjustment of the device to rigid supporting members of different shapes. Alternatively, the device is provided as a toilet seat 1, i.e. combined to a lower rigid member 5. In one embodiment, the device is joined to the rigid member by means of a bi-adhesive tape or any adhesive composition, as disclosed above. In a different embodiment (Figures 1 and 2) the resilient film 4 covering the gelatinous sheet 3 is designed so as to contain the rigid member too. According to this embodiment, there is a unique film 4 covering both the gel sheet 3 and the supporting rigid member 5 but the device and the rigid member are not in direct contact since a diaphragm 10 is provided between the two. The diaphragm 10 is made up of the same resilient polymeric material of the covering film. In a third aspect, the present invention relates to the use of a gelatinous material as defined above for the manufacture of a toilet seat having a near-hydrostatic pressure distribution across the surface area of a body cushioned on the seat. The effect may be due to the fact that it has been found that the cushioned body sinks into the gel. As a result, the body resting on the toilet seat is not exposed to pressure peaks. Also, since a gel material as defined above has shape memory, i.e. it is capable of returning to its original shape after the cushioned body is removed, its use according to the invention has the advantage of reducing the "bottoming out" effect due to a repeated and continued use of conventional cushioning devices. Another advantage of the toilet seat of the invention is that it is comfortable and does not tend to constrict blood flow in the tissue of a human being resting on the device even for long time so that the paraesthesia of lower limbs is reduced or eliminated. As said, the gel sheet has a constrained periphery by means of a resilient polymeric film 4. The presence of the covering film still permits a cushioned body to sink deeply into the upper soft part of the device. Generic flowable media may be drawn by gravity. If such fluid media were used, the toilet seat would thus exert pressure on some portions of the cushioned body as the flowable media attempt to flow in response to the gravitational force. This pressure is commonly referred to as "head pressure". Head pressure can cause discomfort and tissue damage to a human using the cushion. The use of a gel according to the invention has removed the drawback of head pressure because the gel material does not excessively flow. Another advantage of the use of a gelatinous material as defined above combined with the use of a resilient covering film, is that the toilet seat tends to be relatively rigid in a horizontal direction and thus resists horizontal displacing forces, even when a heavy body, such in the case of an obese subject, is resting on it. Consequently, the toilet seat remains substantially stable and the weight of the resting body may be shifted without a concurrent tendency of the seat to move unpredictably underneath the body. Due to its outstanding properties and the presence of the hypoallergenic adhesive, the gelatinous material used to make the toilet seat according to the invention is sufficiently solid at ordinary room temperatures so that even if the upper gel sheet is punctured there is no escape of the gel. A superior durability of the toilet seat is thus provided. Suitable gel materials to practice the invention such as those mentioned above (PurGel®, Oasis® or Oasis elite® and Xcelgel™) are also used in surgery for the manufacture of cushions for a proper positioning of patients during operations. This use requires air circulation between the cushion and the cushioned part of the patient to avoid ulcer formation and lessen the sweat build-up. When these gel materials are used according to the invention, the above advantages are thus also achieved by the toilet seat thus manufactured without relying on complex, expensive, functionally similar, prior art solutions such as the presence of hollow columns. within the device in which the air is forced to flow. Due to the elastic nature of the elastomeric gel material used in the upper portion of the toilet seat, the toilet seat 1 of the invention offers a comfortable protection to a body resting on it even if the cushioned body has significantly sunk into the upper, soft device. In addition, the toilet seat has been found to keep on providing a pressure reduction and distribution effect beneath the portion of the body that has sunk within the gel. All the above advantages and features make the elastomeric gelatinous material as defined above particularly suitable for the manufacture of a toilet seat 1 for water closet 2 to avoid the paraesthesia of lower limbs and injuries correlated to it such as severe straining, fractures, or dislocations, in a subject resting on said toilet and selected among old people, obese subjects and those who suffer with invalidating pathologies to lower limbs. The disclosures in Italian Patent Application No. MI2004A000826 from which this application claims priority are incorporated herein by reference.

Claims

CLAIMS 1. A cushioning device, suitable for the manufacture of toilet seats, comprising a sheet (3) of an elastomeric gelatinous material which is completely covered by a film (4) of a resilient polymeric material that constraints its periphery, wherein said sheet has a minimum thickness of 2cm. 2. A toilet seat (1) comprising a lower rigid member (5) and an upper cushioning device as defined in claim 1 , wherein: - the rigid member (5) is tightly joined to the cushioning device by means of one of the following solutions: - a bi-adhesive tape (8), - an adhesive composition, and - by being wrapped together with the cushioning device within the covering film (4) of the resilient polymeric material, provided that between the rigid member and the cushioning device it is provided a diaphragm (10) made up of the same resilient polymeric material of the covering film (4). 3. Use of an elastomeric gelatinous material for the manufacture of a toilet seat (1) as defined in claim 2, which prevents a decubitus-like effect consisting of the paraesthesia of lower limbs and its correlated injuries, in a subject resting on said toilet seat. 4. Invention according to any claims 1, 2 or 3, wherein - said rigid member (5) is substantially U-shaped and is made up of a material selected among plastics, wood, metals or combinations thereof and - said cushioning device (3 and 4) has a shape that substantially overlaps with, and fits to said rigid member (5). 5. Invention according to any claims 1, 2 or 3, wherein said resilient polymeric material is a polyurethane film. 6. Invention according to any claims 1, 2 or 3, wherein said elastomeric gelatinous material has the following properties: - is a latex-free, - glass-fibre free, - is antistatic, - has shape memory even after repeated use, - is water-repellent, - has no fluid or odour absorption, - is non inflammable and fire-rated as self extinguishing, - is easy to be cleaned, - it can be decontaminated by routine techniques, and - is fungus and bacterial resistant. 7. Invention according to claim 6, wherein said elastomeric gelatinous material is the combination of a silicone or silicone derivative with any hypoallergenic adhesive conventionally used in the medical field for the manufacture of objects which come into direct contact with human or animal bodies. 8. The use of claim 3, wherein said paraesthesia correlated injuries are injuries caused by an excessive pressure of nerves and vessels of the rear part of legs and thighs of a subject. 9. The use of claim 8, wherein said paraesthesia correlated injuries are selected among severe straining, fractures, and dislocations. 10. The use of claim 2, wherein said subject is selected among old people, obese subjects and a subject who suffers with invalidating pathologies to lower limbs.