WATERBEDS

Abstract: A waterbed mattress is made up of a plurality of portions of elongate tube (14) arranged side-by-side, so that the transmission of wave action across the mattress, transversely of the tube portions (14), is inhibited. A single tube (14) can be bent or folded to provide some or all of the parallel portions (14), which preferably extend longitudinally of the frame (10) of the waterbed.

Description: WATERBEDS Thi s invention rel ates to waterbeds and other fl otation furni ture and improvements therein. In the past, waterbeds have been made of a single bladder (typically formed by joining two sheets of vinyl) which is filled with water and heated with an electrical heater positioned underneath the bladder. The bladder and heater are contained within a frame having a base having an impervious lower surface to inhibit the water from leaking onto the floor should the bladder burst or leak. However, if the bladder does burst, all of the water leaks out, often in a rush, and the bed becomes unusable. Any occupants in the bed at the time are l kely to be soaked. The peripheral seam joining the upper and lower sheets of vinyl {or other material ) of the bladder has been a potential source of leaks and attempts have been made to reduce the seam length. Another difficulty with waterbeds is their tendency to transmit waves. In particul ar, i f there are two occupants in the bed, the movements of one occupant are transmitted as waves within the bed to rock the other occupant. Various attempts have been made to i ncorporate dampi ng means withi n the bladder and examples include U.S. Patents 4,152,796; 4,204,289; 4,208,748; and 4,292,702. All of these examples increase the cost of manufacture of the bladder and usually increase the number or length of welds or seams. It is an object of the present invention to provide an improved waterbed, or one which will at least provide the publ ic with a useful choice. Accordingly, in a first aspect, the present invention broadly consists in an article of furniture comprising a frame containing a mattress in the form of a pl ural ity of lengths of flexible tubing capable of containing a l iquid, the mattress being positioned within the frame to provide a flotation layer on which a user may rest. In a second aspect, the present invention broadly consi sts in a mattress comprising a tube of fl exible material adapted to contain l iquid and be fol ded into a waterbed frame to provide a flotation layer upon which one can rest. OMPI X In a thi rd aspect, the present invention broadly consi sts in a mattress comprising a plural ity of lengths of tubing of flexible material adapted to contai n l iqui d, and to be positioned i nto a waterbed frame to provide a flotation layer upon which one can rest. By using one or more flexible tubes the seam length can be minimised (i.e. only at the ends of the tube) whilst at the same time the wall s of the tube or tubes control the spread of waves within the mattress. The above gives a broad description of the present invention, preferred forms of which wil l now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a sectional view through a waterbed of the present invention; Figure 2 is a plan view of a waterbed of the present invention; and Figures 3, 4,and 5 are plan views of al ternative arrangements of the waterbed of the present invention, A typical bed of the present invention comprises a frame 10 incl uding a base pedestal 11 upon which a mattress base 12, which is preferably perforate, and a side frame or upper pedestal 13 are supported. Resting upon the mattress base and confined within the upper pedestal is a flexible tube 14, provided with a bung 15 at either or both of the ends. The tube is partial ly fil led with water and then fol ded within the space defined by the upper pedestal to fill the space, and provide a flotation surface 16 upon which one or two (or more) people may l ie. Because the tube is large enough in vol ume that it can substantially fill the bed space while only partially filled with water, a person resting on the mattress simply causes some of the water to be displaced within the tube, without any tension being applied to the tube wall. The tube can, therefore, simply conform to the user's body shape without any resistance. Preferably, the tube mattress 14 and the mattress base 12 are enclosed within a flexible safety envelope 17 to form a water entrapment reservoir, which provides some protection in the event of water leakage from the tube. The envelope is typically formed of 200 to 250 micron polyethylene. Various arrangements can be provi ded to ensure that the area under the mattress provides a waterproof reservoir. This may be provided with a drain aperture, and a water leakage detection means, typically in the form of a sighting tube, visible from outside the bed. The water entrapment area is preferably part of the pedestal, which can be formed in any convenient manner to provi de support for the fl otation l ayer. It wi l l be generally convenient to provide two or more cross-members between the perforate base and the fl oor, together wi th si de members l ocked together to form a relatively rigid pedestal capable of supporting the weight of water in the flotation layer. By providing a water entrapment area underneath the perforate base of the flotation layer, the risk of leakage interfering with bedding is minimized. Indeed, by providing a further waterproof layer of material over the top of the tube-like members, it is possible to provide heating for the bed in the form of a conventional electric blanket. This can be placed above the tube mattress, so that the risk that water will interfere with the electric blanket is minimized. However, as explained below, electric blankets are unnecessary in any case. Over the envelope there may be a highly stretchable, non-sl ip polyurethane sheet, 50 microns thick, to prevent the upper run of the sheet from "sticking" to the flotation surface and inhibiting its abil ity to conform to the user's body shape. The tube confi guration shown in Figure 2 compri ses the tube bei ng fol ded transversely back and forth across the bed.. This configuration is suited to a single bed or one where the user(s) prefer a "wave" mattress. For example, when applied to a double bed this arrangement suffers from the disadvantage that wave action is directed by the l ie of the tube across the bed, and the movements of one occupant will tend to disturb the other occupant. The configuration shown i n Figure 3 overcomes thi s di fficul ty. In thi s arrangement, waves caused by one occupant's movements are directed l ongitudi nal ly and wi l l be hardly noticed by the other occupant. It i s , therefore, preferred, that the tube be laid so that for the most part the runs of the tube are longitudinal of the bed. It will be noted that the provision of a long tube folded within the confines of a frame tends to prevent two dimensional waves as occur in a conventional bladder. Instead disturbances in this waterbed will tend to be propagated as one dimensional waves along the length of each tube run, which are further damped by the bends or folds in the tube. If desired, there may be a seam 19 in the tube further to inhibit water movement between the two halves of the bed. Alternatively, the tube can be entirely separated at that point, so that there are two d stinct tubes on the bed, one for each occupant, A further optional configuration is shown in Figure 4. Many other configurations are also possible. The flexible nature of the tube allows for circular beds as well as free form furniture without the need for a specially shaped bladder as the tube can simply be folded to fit within a frame of any desired shape. If desired, there may be an additional partition 20, as shown in Figure 5, between the two halves of a double bed, typically made of a flexible material , such as foam plastics. This may be used to provide a thermal barrier between the two users if they wish their mattresses to be heated to di fferent temperatures. Heating can be provided by means of a heater or heaters under the tubing, or el se by an immersion heater in the or each tube. As the tube material is heated (typically to around 35 degrees Cel sius) it becomes more supple and less susceptible to stress cracks. The preferred tube is formed from 475 mm l iefl t tubing with a wall thickness of 0.1 mm. The material is a five layer co-extrusion, the layers comprising l inear low densi ty polyethyl ene, EVA, Nyl on, EVA, and l i near l ow densi ty polyethylene respectively, each layer being 20 microns thick. Many other tube material s and dimensions can be used, however. The only seams in the mattress of the present invention are at the ends of the tube(s). This contrasts greatly with earl ier waterbed mattresses in which the seam, which is the greatest line of weakness in the mattress, extends right around the perimeter. OMP Many modifications may be made without departing from the scope of the present invention as broadly defined or envisaged. For example, there may be more than one layer of tubing in the waterbed. The invention may be applied to articles of furniture other than beds, such as chairs and sofas or divans, as well as to beds or mattresses having substantially non-rigid frames or perimeters, e.g. as shown in U.S. Patents 4,015,299; 4,062,077; and 4,057,862; which are typical of the waterbed genus where the waterfil l ed bladder is concealed within a padded mattress surround. It will be appreciated that various liquids other than water could be used in the bed, such as an oil-l ike substance. Al ternatively, the addition of a thickening substance, such as gelatine, could be used to enhance the comfort of the flotation system. Although it is not illustrated, the water entrapment reservoir in the pedestal could be of a smaller size than the area of the base, so that provision can be made for drawers or the like on either side of the bed. In this case, it is preferred that a waterproof layer be placed over the drawers, to direct water down into the entrapment reservoir.

Claims: CLAIMS : 1. An article of furniture comprising a flexible element capable of containing a liquid to provide support for a user, characterised in that said element comprises at least one elongate tube (1* . 2. .An,article of furniture as claimed in claim 1, characterised in that said tube (14) is bent so that different portions of its length will provide support for the user transversely of the tube (14). 3. An article of furniture as claimed in claim 2, characterised in that said portions are arranged side-by-side. 4. An article of furniture as claimed in claim 3» characterised in that said portions are substantially parallel. 5. "" An article of furniture as claimed in claim 4 in the form of a waterbed mattress having a length and a breadth, characterised in that said portions extend longitudinally of the mattress. ό. An. article of furniture as claimed in claim 1, characterised in that said element comprises a plurality of separate, elongate tubes (14) arranged side-by-side. 7. An article of furniture as claimed in claim β, characterised in that said tubes (14) are substantially parallel throughout at least portions of their lengths. 8. An article of furniture as claimed in claim 6 in the form of a waterbed mattress having a length and a breadth, characterised in that at least most of the lengths of said tubes (14) extend longitudinally of the mattress. 9. A waterbed mattress as claimed in claim 8, characterised in that said tubes (14) are separated by a substantially flexible barrier (20). 10. An article of furniture as claimed in any one of the preceding claims, characterised in that said element lies within a waterbed frame (lO) to provide a flotation layer (16) upon which one can rest.

Inventors: COMPTON RICHARD ALWYN, SPEEDY LLOYD JAMES, COMPTON, RICHARD, ALWYN, SPEEDY, LLOYD, JAMES
Applicants: COMPTON RICHARD ALWYN, COMPTON, RICHARD, ALWYN
Application year: 1984
Main classification: A47C27
IPC codes: A47C27