The present invention relates to shoe insoles and in particular to shoe insole elements that can be inserted into a shoe to augment one or more portions of the insole, or even constitute the entire insole.
Shoe insoles have been designed in various forms in order to provide a cushioning action for the wearer's foot. For example, an insole, or parts of an insole, can be formed of a combination of materials having different respective degrees of stiffness. The materials are typically fixedly joined together, e.g., by adhesive or by embedding one material within another. For example, Published U.S. Application No. 2007/0022630 discloses an insole in which an upper gel layer thereof is formed of a stiffer material than a lower gel layer on which it is situated. The underside of the lower layer forms a series of downward spring walls shaped in various patterns.
In U.S. Pat. No. 6,460,275 there is disclosed an orthotic device used in the heel portion of an insole. The device comprises an upper cup portion formed of a soft silicone material seated on a stiffer wedge portion. The cup portion includes an even more flexible blind bore portion arranged to overlie a cutout in the wedge portion. The blind bore portion is able to be pushed into the cutout by the heel of the wearer to cushion the heel and disperse the heel-strike forces. Although the upper cup portion is removable from the wedge portion, those portions are designed only to be used together, not separately.
It would be desirable to provide an improved way of cushioning a wearer's sole.
It would also be desirable to provide a way of cushioning a wearer's sole in a manner that is adjustable.
It would further be desirable to provide a way of cushioning a wearer's sole in such manner that the degree of cushioning can be adjusted by the wearer.
A shoe insole element comprises an upper portion and a lower portion, the upper portion having upper projections and voids located alongside the upper projections. The lower portion includes lower projections which extend into the voids to resist flexing of the upper projections toward one another under the action of a wearer's foot.
In one aspect of the invention, the lower portion is selectively separable from the upper portion to release the resistance to such flexing. In that event, the upper and lower portions can be of the same or different stiffness.
In another aspect of the invention, the upper and lower portions are not selectively separable from one another, in which case the upper projections are of different stiffness (i.e., more or less stiff) than the lower projections.
The insole element can be configured for use in specific regions of the shoe such as the heel region and/or the arch region for example. Separate insole elements for the respective regions could be provided, or a one-piece insole element covering multiple regions or the entire shoe insole could be provided.
The objects and advantages of the invention will become apparent from the following detailed description of preferred embodiments thereof in connection with the accompanying drawings in which like numerals designate like elements and in which:
Illustrated in the accompanying figures are a heel insert 10 (
In another embodiment, the lower portion is not selectively removable, so the degree of flexibility of the upper projections depends on whether the lower projections are stiffer or less stiff than the upper projections.
Depicted in
The insert's lower portion 14 is shaped to mate with the projections/voids 26, 28 and with the projections/voids 36, 34. Thus, the lower portion includes a center section 39 from which extend a series of finger-like projection 40 arranged in an arc along an outer periphery of the center section 39. Each projection 40 includes a horizontal segment 42 and a vertical segment 44. The projections 40 are separated by voids 46 and are arranged to be received in the voids 28 of the upper portion 12, and the projections 26 of the upper portion are arranged to be received in the voids 46 of the lower portion to resist flexing of the projections 26 under the action of a user's foot.
Extending from a top surface of the center section 39 are concentric annular rib-like projections 45 separated by concentric annular voids 47. The projections 45 are arranged to be received in respective voids 34 of the upper part 12 in order to resist flexing of the projections 34 toward one another under the action of a wearer's foot.
In one aspect of the invention, the lower portion 14 is selectively removable from the upper portion, whereby the heel insert 10 can be used with or without the lower portion 14. Without the lower portion 14, the upper portion is more flexible in the rear region thereof. That is, by removing the lower portion 14 from the upper portion 12 before inserting the heel insert 10 into the heel of the shoe 48 (see
If the user elects to assemble the lower portion 14 with the upper portion, then the ability of the upper projections to flex toward and away from one another will be resisted by the lower projections, the degree of resistance being dependent upon the stiffness of the lower projections. In that regard, the lower projections can have a greater, a lesser, or the same stiffness as the upper projections.
In practice, the wearer would determine whether to utilize both of the upper and lower portions 12, 14 of the heel insert 10, to provide a stiffer cushioning action, or to utilize only the upper portion 12 to provide a more flexible cushioning action.
If only the upper portion 12 is to be utilized, the user removes the lower portion 14 prior to inserting the heel insert into the shoe. If desired, the heel insert can be removed from the shoe in order to mount the lower portion into the upper portion to provide a stiffer cushioning action when returned to the shoe. It is required that the heel insert be outside of the shoe in order for the lower portion to be removed or installed.
In another aspect of the invention, the lower portion 14 is not removable from the upper portion 12, i.e., the lower portion is permanently bonded to the upper portion 12, in any suitable manner, e.g., by adhesive or a chemical bond created by molding one portion to the other In that event, the flexibility of the upper projections will be dependent on the amount of the difference in stiffness between the upper and lower projections.
The upper and lower portions 12, 14 can be formed of any suitable materials, most preferably a visoelastic polymer or silicone gel which is highly energy absorbent. Preferred materials include, but are not limited to, thermoplastic elastomers including styrene-olefin-rubber block copolymers, ethylene copolymers, thermoplastic polyolefins, thermoplastic polyurethanes, polyamides, polyureas, polyesters, thermoplastic rubbers, natural rubbers, nylon, ethylvinyl acetate and other materials whose softness is a function of temperature.
Depicted in
The lower portion 54 includes rib-like lower projections 72 spaced apart by upwardly open voids 74. The projections 72 are linear and parallel and are arranged on a flat base portion 75. The projections 72 are arranged to extend into the voids 70 of the upper portion in order to prevent the upper projections 68 from flexing toward one another (i.e., from flexing into the voids 70). As in the case of the first embodiment, the lower portion 54 can be selectively removable from, or permanently bonded to, the upper portion 52. If selectively removable, then by removing the lower portion 54 from the upper portion 52 before inserting the arch insert 50 into the shoe, the projections 68 would be able to flex freely toward one another in response to forces applied by the wearer, the flexing occurring in the generally front-to-rear (longitudinal) direction of the shoe.
If the lower portion 54 is assembled with the upper portion 52, the ability of the upper projections 68 to flex is resisted, depending on the amount of difference in flexibility between the upper and lower projections. The lower projections 72 can be of greater, lesser or equal stiffness relative to the upper projections 68.
If the lower portion 54 is permanently bonded to the upper portion 52, then the degree of flexibility depends upon the amount of the difference in flexibility between the upper and lower projections.
When the lower portion 54 is inserted into the upper portion, a bottom surface 77 of the lower portion lies flush with the border 73 of the upper portion 52.
The upper and lower portions 52, 54 can be formed of the same materials described earlier in connection with the heel insert.
Although the heel and arch inserts 10, 50 have been described thus far as separate units, it will be appreciated that they could be combined into a single integral unit 100 for insertion into the heel/arch region of the shoe as shown in
Although the present invention has been described in connection with preferred embodiments thereof, it will be appreciated by those skilled in the art that additions, deletions, modifications, and substitutions not specifically described may be made without departing from the spirit and scope of the invention as defined in the appended claims. For example, the projections and voids shown in the preferred embodiments could be shaped or oriented differently or disposed at different locations than the ones shown.