US2715674A - Electrically heated mattress and sleeping pad - Google Patents

Description

' g- 1955 H. c. ABBOTT ET AL ELECTRICALLY HEATED MATTRESS AND SLEEPING PAD Filed March 12, 1955' 3 j yyfoiidf gi/milai ZZ 00mm g 97mm v 5% W 10 fir? United States Patent ELECTRICALLY HEATED MATTRESS AND SLEEPING PAD Howard C. Abbott, Chicago, and Thomas J. McDermott,

- Oak Park, Ill.

Application March 12, 1953', Serial No. 341,858

3 Claims. (Cl. 21946) Our invention relates to an electrically heated mattress and sleeping pad.

One of the objects of this invention is to provide an electrically heated mattress and sleeping pad, formed of a foam latex material of a thickness which will cause the heat to be transmitted to the body and which will cushion the heating element so that same does not impart any unevenness or lumping to the pad.

Other objects of this invention are to provide an electrically heated mattress and pad formed of a material such as foam latex which may be used by persons with allergic conditions, which will not absorb liquids, moisture or perspiration, which is sanitary, and which is highly resilient.

The prior art electrically heated mattress and sleeping pads are made of a cloth or fabric material in which the heating element is sewn or stitched to the cloth. Such cloth pads or coverings are objectionable to persons suffering from allergic conditions, likewise the cloth tends to absorb water, moisture and perspiration and hence become unsanitary unless cleaned frequently. Furthermore such cloth coverings are not sufficiently resilient. In addition such fabric coverings require the use of sewing machines and skilled operators and the stitching of the heating element or electric wire to the pad is laborious and time consuming, all adding to the cost of the product. All of the foregoing objections are eliminated with the use of this invention.

Other objects will become apparent at this description progresses:

In the drawing:

Fig. 1 is a top plan view partly broken away of a heated mattress and sleeping pad in accordance with our invention.

Fig. 2 is an enlarged cross-sectional view taken on lines 22 of Fig. 1, and

Fig. 3 is a cross-sectional view taken on lines 33 of Fig. 1.

The pad is made up of a pair of layers of foam latex material, indicated at and 12, cemented together, between which is secured, as will be presently described, the heating means. The layers 10 and 12 of foam latex material are each approximately inch in thickness and of a length and width of the size of a mattress.

The heating means generally indicated at 14, which is positioned between the two layers 10 and 12, comprises a resistant alloy wire 16 preferably of a size number 33, American Wire Guage. This wire is wound helically around a plastic core 18 and both the core 18 and wire 16 are enclosed in a sleeve 19 which is formed of a thermoplastic coating compound. The wire 16 preferably has a resistance of three ohms per running foot and develops a maximum temperature of 75 C. The heat developed by the pad is determined by the total resistance of the heating means, the length of which is adjusted so as to develop a temperature which is about three degrees above normal body temperature. This condition is true so long as the heat can be dissipated into the surrounding space. Thus, under such a condition the heat of the pad will never exceed the temperature indicated. The heating means 14 is preferably in a continuous length, as shown in Fig. 1, and is arranged in a pattern comprising a series of reversing lines which are spaced in substantially parallel relationship so as to cover approximately of the area of the pad. Thus, the head portion of the pad indicated by the numeral 17 upon which the pillow rests has no heating means, while the major portion of the pad on which an individual would normally recline, is substantially covered with a network of the heating means. While the heating means is shown as arranged in a reversing line pattern, it will be understood that it may be arranged in any suitable pattern, such as concentric circles, a spiral or any other pattern desired.

A rubber cement 20 is applied to the inside of each of the layers 10 and 12 and the heating means is then laid out, as shown in Fig. 1 on one of said layers and the other layer is then superimposed so that the two layers of foam latex adhere to each other with the heating element securely positioned therebetween.

The terminal portions 14a and 14b of the heating means 14 are attached to the terminals of a conventional electric cord 22 which is connected to a conventional elec tric plug 24. A switch 26 may be connected on the circuit. A strip of tape material 28 of rectangular shape is positioned adjacent the electrical cord 22 and is cemented and secured between the two layers of foam latex 10 and 12. This prevents any breaking or disconnecting of the terminal portion which may be caused normally by virtue of any tensile stresses applied to the cord.

With the two layers secured as described, a fabric tape 30 is rubber cemented and secured to the border completely around the sides and ends of the pad with the fabric tape overlapping the layers. The pad may be cleaned in the usual manner in which foam latex is cleaned. The electrical wires associated therewith are completely enclosed and waterproofed. Since foam latex is an insulator, uncovered electrical wire may be used. The pad may be used for infants as it will not absorb any liquid, nor will it absorb moisture or perspiration. Due to the resiliency of the pad the danger of breaking of the electrical wire 16 is eliminated.

In use, the pad aforedescribed is merely placed on a conventional mattress to overlie the top surface thereof.

It will be understood that various changes and modifications may be made from the foregoing without departing from the spirit and scope of the appended claims.

We claim:

1. An electrically heated mattress pad adapted to be removably positioned over a mattress and comprising a pad body formed of a pair of foam latex layers secured together by a rubber cement, each layer being approximately A inch in thickness and of a size to substantially cover an entire mattress, an electrical heating element disposed and secured between said layers to cover substantially not more than three-fourths of the area thereof with the head portion of said pad without said heating element, said heating element adapted to develope a maximum temperature of C. and including a wire spirally wound around a core with said wire and core covered by a sleeve in contact with the adjacent surfaces of said latex layers, and a tape secured around the border of said pad.

2. An electrically heated mattress pad adapted to be removably positioned over a mattress and comprising a pad body formed of a pair of foam latex layers secured together by a rubber cement, each layer being approximately A inch in thickness and of a size to substantially cover an entire mattress, an electrical heating element disposed and secured between said layers to cover substantially not more than three-fourths of the area thereof with the head portion of said pad without said heating element, the terminal portions of said heating element connected to an electrical cord extending through said head portion adjacent one side thereof, a strip of tape material positioned adjacent the electrical cord and cemented and secured between the foam latex layers, said heating element adapted to develope a maximum temperature of 75 C., and a tape secured around the border of said pad.

3. An electrically heated mattress pad adapted to be removably positioned over a mattress and comprising a pad body formed of a pair of foam latex layers secured together by a rubber cement, each layer being approximately inch in thickness and of a size to substantially cover an entire mattress, an electrical heating element disposed and secured between said layers to cover substantially not more than three-fourths of the area thereof With the head portion of said pad without said heating element, the terminal portions of said heating element connected to an electrical cord extending through said head portion adjacent one side thereof, a strip of References Cited in the file of this patent UNITED STATES PATENTS Re. 21,474 McCleary June 4, 1940 1,837,117 Dunbar Dec. 15, 1931 1,997,899 Dick Apr. 16, 1935 2,288,232 Driscoll June 30, 1942 2,298,181 Stranszky Oct. 6, 1942 2,606,996 Westerberg et al. Aug. 12, 1952 2,688,070 Freedlander Aug. 31, 1954

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