US 3914881 A
A support pad including an envelope of flexible material is disclosed. A core of cellular material occupies substantially all of the space in the envelope. A liquid is dispersed in the cells of the core, the amount of the liquid being less than that which will saturate the core.
Claims available in
Description (OCR text may contain errors)
United States Patent Striegel 5] Oct. 28, 1975 [5 SUPPORT PAD 3,237,319 1/1966 Hanson 36/71 X 36 71 X 1 287 Costa Mesa Calif- 92627 3,724,106 4 1973 Magidson 36/44 3,765,422 10/1973 Smith 128/594  1975 3,795,994 3/1974 Ava 36/29  Appl' 546362 FOREIGN PATENTS 0R APPLICATIONS 406,529 3/1934 United Kingdom 36/44 36/44; 128/594; 36/71; 172,187 7/1960 Sweden 128/594 136/29 CLZ Primary Examiner-Alfred Guest  Field Of Search 36/44, 71, 29, 25 R; Attorne Agent, or Firm-William F McDonald 128/594, 595  R f Ct d 57 ABSTRACT e erences l e A support pad including an envelope of flexible mate- UNITED STATES PATENTS rial is disclosed. A core of cellular material occupies 2,080,469 5/1937 Gilbert 36/29 substantially all of the space in the envelope. A liquid 2,084,517 6/ 1937 V0881 36/29 X is dispersed in the cells of the core, the amount of the 2477588 8/1949 'f 36/44 X liquid being less than that which will saturate the core. 7 3,121,430 2/1964 ORe1l1y..... 128/594 X 3,170,178 2/19 65 Scholl 36/44 X 4 Claims, 8 Drawing Figures III/II/II/l IIIIIII/IIIIIIII/IIIII,
U.S. Patent Oct. 28, 1975 Sheet10f2 3,914,881
US. Patent Oct. 28, 1975 Sheet2o f2 3,914,881
SUPPORT PAD BACKGROUND OF THE INVENTION The present invention relates to support pads. 'It is particularly applicable to the use of support pads for supporting parts of the human body, such as the sole of the foot or some part thereof.
Various people have suffered from various ailments over the years which would be alleviated or at least made more endurable if the afflicted portion of the body received additional support in some way. For example, athletes might be able to perform better or not tire as easily in their particular sport if their feet were to receive more support than the normal shoe construction will give them. Long distance walkers and runners also would benefit from an improved support for their feet. Many supplemental or special supports for the human foot have been proposed in the past. Foam or sponge pads have been tried. They do help somewhat, but are not as effective as one might desire. Fluid filled pads, either gaseous or hydraulic, have been tried. However, the freely moving fluid has presented a number of problems. Paste filled supports or supports filled with small glass beads have been tried. All have helped to some extent but none have been entirely satisfactory. Either it is difficult to have the support in the right place at the right time or there'are durability problems and very serious problems for the user if the support should burst, for example, if the support is a waterfilled pad containing free water.
Accordingly, there has continued to be a very real need for a support pad which will support the desired areas in the desired manner and at the same time be durable and easily applied.
SUMMARY OF THE INVENTION It is an object of the present invention to provide a support pad which overcomes the deficiencies of the prior art. The device is simple and easy to apply and use and at the same time quite durable. The construction is such that support is automatically maintained in the necessary areas depending upon what the user is doing.
The support pad comprises an envelope of flexible material. A core of cellular material occupies substantially all of the space within the envelope. A liquid is dispersed in the cells of the core, the amount of the liquid being less than that which will saturate the core.
Other objects and advantages of the present invention will be apparent from the following detailed description in conjunction with the accompanying drawmgs.
BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are illustrative of advantageous embodiments of this invention.
In the drawings: FIG. 1 is a top plan view of a support pad for the human foot according to the present invention;
FIG. 2 is an elevational view, in section, taken along line 2-2 of FIG. 1;
FIG. 3 is a partial top plan view, with parts removed for purposes of clarity, showing liquid being inserted into the structure of FIG. 1;
FIG. 4 is a top plan view, with parts partially removed for purposes of clarity, of the support pad of FIG. 1;
FIG. 5 is a partial top plan view of another embodi ment of the present invention;
FIG. 6 is a side view illustrating a foot resting on a pad according to the instant invention;
FIG. 7 is a side view of the pad of FIG. 6 showing the effect of the foot pressure on the heel.
FIG. 8 is a side view of a foot with pressure on the toes showing the movement of fluid to the heel area of the embodiment shown in FIG. 6;
DETAILED DESCRIPTION FIG. 1, the support pad is for supporting part of the human body, particularly the foot and the pad is shaped to conform to the part of the body, i.e. the foot, being supported.
Referring now to FIG. 2 it will be seen that envelope 12 comprises two sheets of flexible material 18, 20. Core 22 of cellular material occupies substantially all of the space within envelope 12. An appropriate means for forming sheets 18 and 20 into an envelope 12 around core 22 is by disposing the three materials one on top of the other in the order in which they will be present in the final pad 10 and then heat and pressure bonding the edges to one another and sealing envelope 12 by suitable hot stamping means and the like, as is well known to those skilled in the art.
Core 22 may be of any suitable cellular material. Desirably,.the cellular material is fully reticulated, open pore, cellular structure. A particularly effective material is a fully reticulated open pore polyurethane foam manufactured by the Scott Paper Company and sold under the trade name product No. 250. This material has a density of 4.7 pounds per cubic foot, a compression-deflection of 0.21 PSI at 25 percent, a 27 percent ball rebound, a 10 percent compression set, a percent ultimateelongation, and'a 16 PSI tensile strength, all determined by the ASTM Procedure 1564-64T Method. The compression deflection value shows the pounds per square inch required to compress one inch thick foam by a comparable percentage.
Referring now to FIG. 3, an appropriate means of dispersing liquid in the cells of core 22 may be seen. A hypodermic syringe 24 containing an appropriate amount of liquid 26 such as water is inserted by means of its needle 28 through opening 14 in envelope 12. The liquid 26 is then injected by hypodermic syringe 24 into the cells of core 22. Needle 28 is removed from opening 14 and adhesive sealant 16 applied thereto as shown in FIG. 1. It is an important feature of the invention that the amount of liquid present in the core is less than that which will saturate the core. No free water, i.e. water that can move about freely should be present. All the water present should be dispersed in the cell structure of core 22. In a typical application of a support pad 10 to support a human foot of average size, say mans shoe size 8, the amount of liquid present is about 8 to about 25 cubic centimeters. This amount of water is so slight relative to the amount of core structure in which it is dispersed that if one were to then cut open pad 12 the core 22 would appear at best only very slightly damp. No undispersed water would be apparent.
The amount of liquid present may of course be varied somewhat with the weight of the part of the body, which generally is proportional to the overall weight of the human being being supported. More water will be required in pad 10 to support a heavy human than a light human. However, in no case should the amount of water be at a level that will fully saturate the core. In all cases it should be less than saturated.
FIG. 4 is a partially cutaway view of the pad shown in the preceding figures and illustrates the overall structural arrangement of the various components, i.e. sheets 18 and 20, which are bonded together to form envelope 12, with core 22 occupying substantially all of the space within envelope 12. The amount of liquid 26 present is uniformly dispersed in core 22 and therefore no free water i.e. water which is not dispersed in the cells of core 22 can be detected by the naked eye.
In the embodiments shown in FIGS. 1 through 4 inclusive it is apparent that pad 10 is shaped like the entire plantar area of the human foot. In fact, while this will be desirable much of the time it may not always be necessary. Pad 10 may be shaped like no more than the area of the foot or other part of the body which it is desired to specifically support. FIG. 5 illustrates such a pad which is designed to support the plantar area of the foot from the ball of the foot back, and not support the toe area.
Referring now to FIGS. 6 through 8 inclusive, the operation of pad 10 when the weight of the body is variably applied thereto by means of the movement of the human foot may be observed. As shown therein, foot rests on pad 10. As can be seen in FIG. 6, when foot 30 is not moving, the amount of liquid 26 in core 22 of pad 10 is sufficient, together with the inherent resiliency of core 22 to keep either the heel area 32 or the toe area 34 of foot 30 supported or both supported. Referring now to FIG. 7, when heel 32 bears the pressure of the body in a forward walking movement, the liquid 26 dispersed in the heel area of core 22 tends to act as a hydraulic shock absorber and cushion in impact of heel 32. The pressure of heel 32 on support pad 10 will tend to force some of liquid 26 out of the cells of core 22 immediately therebelow and forward towards the area of support pad 10 below toes 34. Thus the ball 36 of the foot and toes 34 are received by a semi-hydraulic cushion of liquid 26 dispersed in the cells of core 22. This disperses the pressure evenly over the plantar area of foot 30. Then, referring to FIG. 8,as one continues with a walking movement, as shown in FIG. 8, the pressure now is concentrated on toe area 34 of the foot 30. Ball 36 and toes 34 take the weight of the body, initially compressing core 22 therebelow. This will tend to push liquid rearwardly to the area of core 22 in pad 10 below heel 32. This tends to support the entire plantar area of the foot rearward of ball 36 and spread the pressure uniformly over the entire plantar area of foot 30. At all times the arch and metatarsal will receive support. The action is repeated every time one goes through a walking step.
It will be appreciated that while there have been shown and described hereinabove possible embodiment of this invention, the invention is not limited thereto, and various changes, alterations, and modifications can be made thereto without departing from the spirit and scope thereof as defined in the claims.
What is claimed is:
1. A support pad comprising:
a. an envelope of flexible material;
b. a core of cellular material occupying substantially all of the space within the envelope;
0. a liquid dispersed in the cells of the core, the
amount of liquid being less than that which will saturate the core.
2. The support pad of claim 1 wherein the pad is for supporting part of the human body and the pad is shaped to conform to the part of the body being supported.
3. The support pad of claim 2 wherein the pad is supporting part of a foot and the amount of liquid present is from about eight to about twenty-five cubic centimeters.
4. The support pad of claim 1 wherein the core of cellular material is an open-pore polyurethane foam.