US 2917843 A
Description (OCR text may contain errors)
Dec. 22, 1959 v w, SCROLL 2,917,843
FOOT CUSHIONING DEVICE WITH SECURED PAD F1186 56131;. 13, 1956 2 Sheets-Sheet l 4 1 5 :7 Tax Dec. 22, 1959 w. M. SCHOLL 2,917,843
FOOT CUSHIONING DEVICE WITH SECURED PAD Filed Sept. 1:5. 1956 2 sheets-shed 2 Maw/v #62404 L 15; 444 aw. zwpafiir United States Patent FOOT CUSHIONING DEVICE WITH SECURED PAD William M. Scholl, Chicago, Ill.
Application September 13, 1956, Serial No. 609,738
6 Claims. (Cl. 36-71) This invention relates to improvements in a foot cushioning device with a secured pad, and more particularly to a foot cushioning device which may readily be made in the form of a full or partial insole for disposition in a shoe or the like beneath the plantar surface of the foot, the device being provided with a pad or a lift at a judicious location depending upon the treatment desired for a particular foot, although the device may have other uses and purposes as will be apparent to one skilled in the art. 1
In the past, many and various types of foot cushioning devices for insertion in a shoe or other article of footwear and which incorporated a pad or lift at some judicious location, have been developed, but: in every instance of which I am aware devices of this character in which the laminations were secured together by heat sealing did not employ such a lift. Frequently, cushioning devices as heretofore known and which were provided with a lift did not have the layers or parts thereof heat sealed together, and the lift was free to move out of position. In other cases, where laminated foot cushioning devices were made with the lift secured, the, entire structure was objectionally expensive. Further, while cushioning insoles have heretofore been provided especially for use in ladies high-heeled and open-heeled shoes, such insoles were extremely diflicult to maintain in proper position, and frequently wrinkling of the device resulted particularly if it incorporated a metatarsal liftvand the lift itself was disposed at the sharp bend where the sole turns from the tread into the shank of the toe.
With the foregoing in mind, it is an important object of the instant invention to provide a foot cushioning device embodying a lift, and wherein the laminations of the structure may be heat sealed together at the bounding edges and also around the lift, whereby the lift is maintained positively in position. I
Another object of the invention is the provision of a foot' cushioning device embodying a plastic cover member and a plastic cushioning member heat sealed together at the very bounding edges, andwith a lift dis-' posed between said members, with the members heat sealed together inside the bounding edges around the lift itself.
Also a feature of the invention resides in the provision of a foot cushioning device embodying a thermoplastic cover sheet, a thermoplastic cushioning sheet, and a thermoplastic lift inserted between said sheets, the sheets being heat sealed at their bounding edges, and also heat sealed together around the lift with the very edge of the lift itself caught in the heat seam.
It is also a feature of this invention to'provide a foot cushioning device embodying a thermoplastic cover member, a thermoplastic cushioning member, and a lift element interposedbetween said members, the members being heat sealed to eachother at their'bounding edges and also around the lift, but the members and the lift being otherwise unconnected to each other.
A 2,917,843 Patented Dec. 22, 1959 It is also an object of this invention to provide a foot cushioning appliance highly desirable for use in ladies open-heeled shoes, the device being so constructed as to stay in position against slippage, and so arranged as to be substantially invisible when worn, and yet the laminations of the device are heat sealed together.
Still another object of the invention resides in the provision of a laminated foot cushioning insole highly desirable for use in a ladies high-heeled open-heeled shoe, which insole is laminated from thermoplastic materials including one layer of thermoplastic foam which is heat sealed to a top lamination by a graduated heat sealed seam, whereby the foam layer is given a rounded margin gradually decreasing in thickness to a fine edge seal, so that when the foot is placed upon the device, the
' device itself is substantially invisible.
Also a feature of the invention is the provision of a foot cushioning insole for disposition in a high-heeled shoe, which insole includes a cover lamination, a cushioning lamination, and a metatarsal lift in the form of a cushioning member disposed between the two laminations which are heat sealed together at the bounding edge and also around the lift, but being otherwise unattached to each other or to the lift, whereby the device will not wrinkle when in use even though the lift is disposed at the sharp bend between the tread of the sole and the shank of the shoe.
Still a further object of the instant invention is the provision of a laminated heat sealed foot cushioning appliance having a secured lift therein which may be extremely economically manufactured.
While some of the more salient features, characteristics and advantages of the instant invention have been above pointed out, others will become apparent from the following disclosures, taken in conjunction with the accompanying drawings, in which:
Figure 1 is a plan view of a foot cushioning device embodying principles of the instant invention;
Figure 2 is a fragmentary central vertical sectional view illustrating the device of Figure l in operative position in a high-heeled, open-heeled shoe;
Figure 3 is a greatly enlarged fragmentary transverse vertical sectional view taken substantially as indicated by the line III-III of Figure 1, looking in the direction of the arrows;
Figure 4 is a plan view of a foot cushioning device of slightly different construction, but also embodying principles of the instant invention;
Figure 5 is a transverse vertical sectional view taken substantially as indicated by the line VV of Figure 4; v
Figure 6 is also a plan view of ;a foot cushioning device of still different construction;
Figure 7- is a transverse vertical sectional view taken substantially as indicated by the line VIIVII of Figure 6; i Figure 8 is a plan view of another form of foot cushioning device embodying principles 'of the instant invention;
Figure 9 is a transverse vertical sectional view taken substantially "as indicated by the line IXIX of Figure 8. 1 1
As shown on the drawings:
The first illustrated embodiment of the instant invention, shown in Figures 1, 2 and 3, is in the form of. a shortened insole highly desirable for disposition in a ladies open-heeled shoe. V 1
This form of the invention preferably comprises a cover sheet or lamination 1 which is preferably relatively'thin and made era thermoplastic material; This cover sheet maybe provided with numerous perforations as indicated at 2, if so'desired.
Underneath that cover sheet is a second and preferably much thicker sheet or lamination 3 of cushioning material which may be in the nature of thermoplastic foam having intercommunicating cells.
By way of example but not by way of limitation, it may be mentioned that a satisfactory material for the cushioning sheet is vinyl foam which may be made from a liquid composition generically known as a plastisol. Such plastisol itself may be a dispersion or suspension of polyvinyl chloride resin, or a copolymer in one or more plasticizers such. as a high boiling ester, for example, dioctyl phthalate, dioctyl adipate, dicapryl phthalate, etc., the plastisol being expanded and then cured to provide an open cell, flexible, structural material.
The cover sheet 1 may satisfactorily be a vinyl film and have substantially the same chemical constituency as the foam sheet, but is made under a different process without expansion and is ultimately rolled by a calender into the resulting sheet or film. Obviously the covered sheet has considerable more density than the foam lamination.
The advantages of the substances abovementioned are more fully pointed out in my co-pending application entitled Foot Cushioning Devices filed September 12, 1956, Serial No. 609,453.
The instant invention also may satisfactorily be manufactured under the process more fully set forth, described and claimed in that co-pending application.
The covering and cushioning laminations are preferably sealed together by electronic heat sealing means, in a fine edge seam at the bounding edges of the sheets as indicated at 4. The heat sealing means are so constructed as to preferably give a graduated heat scaling effect on the marginal portion of the cushioning sheet 3 so that while the bounding seam is a fine edge seam, the cushioning material is affected by the heat sealing operation in a manner to provide a curvate marginal portion which gradually decreases in thickness to the fine edge seam, even though the sheet of cushioning material was initially flat. This curyate margin of the cushioning material is indicated at 5 in Figures 2, 5, 7 and 9 of the drawings. The arrangement renders the actual edge seam 4 of the heat sealing operation substantially invisible.
Between the cover sheet 1 and the cushioning sheet 3 a metatarsal supporting pad or lift 6 is preferably interposed. This lift 6 may be of the same material 'as the cushioning sheet, and of the same or a different thickness, depending upon the degree of support desired. Around the metatarsal lift 6 the upper and lower laminations 1 and 3 are preferably heat sealed together as indicated at 7, and the very edge portion of the lift 6 is preferably caught in this heat seal as indicated at 8, so that the very edge of the lift is also attached to the two other laminations.
As is indicated by the exaggerated spacing at 9, the cover sheet and cushioning sheet as well as the lift 6 are separate from each other andunconnected everywhere but at the seams 4 and 7.
With reference to Figure 1, it will be seen that the insole has a slight recess 10 in the forward end contour thereof, and a similar recess 11 in the rear end contour. As seen in Figure 2, the device is of such length that the metatarsal heads will rest upon the cushioning device, but the toes of the foot will project therebeyond, and the rear end of the device terminates under the forepart only of the heel of the user. Thus, when the device is disposed in an open-heeled shoe generally indicated by numeral 12, and in this instance the shoe is also of the high-heeled type, both the toes and heel of the user will project beyond the insole. In this instance, the metatarsal lift 6 will be disposed inside the bend 13 where the tread of the sole turns upwardly into the relatively high shank of the shoe.
Even though the metatarsal lift is located precisely in the bend 13, there will be no wrinkling, particularly of the cover layer 1, while the device is in. use. That is be.-
cause the cover is not connected to the lower layer or to the insert except at the heat sealed seams. This freedom from connection except at the heat sealed seams also provides another advantage .in that it permits a ready pumping of air from the air pervious foam layer 3 through the apertures 2 in the cover layer, if apertures are provided. On the other hand, if apertures are not provided an extra cushioning effect is obtained by virtue of air entering between the layer 3 and the cover upon pressure relief during walking. When pressure of the foot is again applied, that air will have to be driven in the reverse direction through the cushioning medium and so affect anadded cushioning and massage of the foot. It will also be noted that the arcuate margin 5 of the cushioning layer eliminates any objectionalbe ridge under the foot, permits the cover to tightly contact the shoe itself, and .thus enhance the invisibility of the appliance when in use. Additionally, the soft clinging action caused by the surface of the cushioning layer against the inside of the shoe effectively maintains the device in place against slipping.
It should also be noted that the device is simple in construction, very economical to manufacture, long lived, and may be laundered whenever desired.
In Figures 4 and 5, by way of example, I have shown a full insole utilizing the same metatarsal lift 6 as above described, and made in the same way. In this instance, the insole has the top layer 1a, the bottom layer of cushioning material 311, and these are of the same character as described in connection with Figures 1 to 3 inclusive, except for the external contour. The two layers are heat sealed together at a fine edge seam 4, the bottom layer has the arcuate margin 5, and the layers are heat sealed around thev metatarsal lift 6 as indicated at 7 with the very edge of the lift engaged in that seal. As shown at 9, the layers are otherwise unsecured to each other.
In Figures 6 and 7 I have illustrated a still different form of insole, comprising a top lamination 1b and a cushioning lower lamination 3b heat sealed together as at 4, with the lower cushioning layer having the rounded marginal portion 5. In this instance, however, I have illustrated the inclusion of an added heel lift 14 which is inserted between the upper and lower laminations at the rear end of the device so as to give the heel of the foot an added cushioning support and an added elevation. In order to maintain the added heel lift 14 in position, it is only necessary to heat seal the upper and lower layers together in a transverse line to form the seam 15 in front of the heel lift. As may be noted from the Figure 7, the heel lift 14 need not be engaged in the edge seam 4, although the forward edge of the lift may be engaged by the seam 15, if so desired. Obviously, it is impossible for the heel lift to change position.
By way of further example, I have shown in Figures 8 and 9 an insole with a longitudinal arch lift or support. In this instance, the insole comprises the top lamination 1c, the bottom cushioning lamination 30, heat sealed as at 4 and the lower lamination has the arcuate margin 5, all as above explained. Between these layers a longitudinal arch lift or supporting element 16 is inserted, and this, of course, may be of the same constituency as the cushioning layer 30, and of whatever thickness is'deemed necessary. With the lift 16 in position, the parts 10 and 3c are preferably heat sealed together around the lift as indicated at 17 in a curvate seam, the ends of which reach the bounding edge seam 4. Preferably, the very edge of the insert '16 is engaged in the seam 17 as above explained.
The structures shown in Figures 4 to 9 inclusive-have been given by way of examples of some of the variations that may be made in the instant invention without departing from the teachings hereof. In each instance a foot supporting device that is highly eflicient in use, long lived, and economically manufactured is provided, and the invention has sufficient universality to provide corrective cushioning pressure for substantially any type of affiiction that may be alleviated by cushioning or'supporting contact with the plantar surface of the foot.
It will be understood that modifications and variations of a further nature may be affected without departing from the scope of the novel concepts of the present invention. I
Iclaim as my invention; I
1. In a foot cushioning appliance, a plastic cover sheet, a thicker plastic foam cushioning sheet coextensive with and underlying the cover sheet, a smaller plastic foam cushioning element positioned between said sheets in an together at their edges, and a fused joint securing said sheets together around said element leaving the sheets fixed position, and the fused joint around said element also including the'edge of said element.
3. In a foot cushioning appliance, a cover sheet, a thicker cushion sheet underlying said cover sheet and secured thereto at the edges of said sheets, a cushion element smaller than said sheets disposed therebetween, and a line of securement between said sheets around said element whereby said sheets are unattached to each other elsewhere than at their edges and said line of securement and said element is maintained in fixed position.
4. In a foot cushioning appliance, a cover sheet, a thicker cushion sheet underlying said cover sheet and secured thereto at the edges of said sheets, a cushion element smaller than said sheets disposed therebetween, and a line of securement between said sheets around said element sufficiently close to said element to maintain the margin of the element curved toward the line of securement.
5. A foot cushioning appliance in the-form of a shortened insole for womens open-heeled shoes, comprising a cover sheet, a thicker sheet of cushioning material underlying said cover sheet and secured thereto at the edges of the sheets, a metatarsal lift between said sheets, and a line of securement between said sheets around said lift throughout their foot supporting surfaces.
6. A foot cushioning appliance in the form of an insole to underlie the plantar surface of the foot, comprising a otherwise unattached and holding said element trapped in cover sheet, a thicker foam sheet coextensive with said cover sheet and secured thereto at the edges of the sheets, a foam heel lift between said sheets, and a transverse line of securement between said sheets in front of said heel lift leaving said sheets otherwise unattached to each other throughout their foot supporting surfaces and trapping said heel lift in fixed position.
References Cited in the file of this patent UNITED STATES PATENTS OTHER REFERENCES Modern Plastics Periodical, Nov. 1954 (pages 106-108 and 214-216), Plastic Digest.