Backless Clog Construction

Abstract

A comfortable, backless clog having a specially shaped rigid upper and a rigid lower is disclosed herein. The clog is held comfortably and snugly to the foot of the wearer by a unique arrangement including a foam lining which cooperates with the rigid upper and lower to define a "keyhole" opening into which the skewed foot of the user may be inserted and then rotated to lock the foot securely in the clog. The clog may be made from wood or plastic and provides a new shoe construction having the appearance of so-called "wooden" shoes, or "Dutch" shoes.

Description

BACKGROUND OF THE INVENTION

Wooden shoes, especially Dutch-type wooden shoes are very well known to the art. Indeed, the patent literature includes disclosures of such wooden shoes dating back more than a hundred years. Foam lined shoes and foam lined rigid boots, all having backs and/or ankle supports, are also well known to the art, and the patent literature is replete with disclosures of this type of ski boots. However, heretofore, a "Dutch shoe" type of clog, which may be securely, safely, and comfortably held to the foot of the wearer and which may be mass produced at reasonable cost, has not been available to the art. Accordingly, it is to the provision of a new and improved "wooden shoe" type construction (although the present shoe may also be manufactured from injection molded plastic or other comparable rigid materials) that the present disclosure is directed.

SUMMARY OF THE PRESENT INVENTION

The new shoe construction comprises essentially a specially configured and foam filled rigid upper and a contoured rigid lower, which rigid elements give the new clog the general appearance of a conventional wooden shoe. However, in accordance with the invention, the rigid upper is shortened and does not include any back portion. The rear edges of the upper are specially arched and disposed in a plane canted with respect to the lower. Most importantly, the upper and lower combine to form an "oversized," in relation to the foot size intended to be accommodated by the new clog, cavity for the foot of the wearer. This cavity is "overstuffed" with a specially configured, partly folded liner of expanded plastic foam sheet material, such as flexible, resilient, polyurethane foam. The liner is blanked out of sheets of foam material and specially shaped and folded to line or to "overstuff" the cavity and to define a foot space between the upper and lower.

Specially, the folded foam liner defines a narrow "keyhole" or throat opening which may be entered by the foot only when it is rotated slightly to a position generally parallel with the opening, a position in which the foot is in a vertical or inclined plane, rather than in a horizontal plane of the surfaces of the lower. In this manner, the user of the shoe may "lock" his foot therein by turning the foot, after its widest portions have passed through the narrow throat opening, to a position in which the widest portions of the foot are in a horizontal plane and locked behind the narrow throat opening. It will be understood, of course, that the flexible foam provides cushioning of the upper portions of the foot as well as locking of the foot within the clog.

For a more complete understanding of the present invention and a greater appreciation of its attendant advantages, reference should be made to the accompanying drawings and the following detailed description.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front, perspective view of a new and improved clog embodying the principles of the present invention;

FIG. 2 is a rear, perspective view of the clog of the invention;

FIG. 3 is a cross-sectional view of the upper of the invention showing details of construction of the plastic foam lining;

FIG. 4 is a plan view of the new and improved foam liner blank of the present invention;

FIG. 5 is a perspective view showing the manner in which the liner is folded twice upon itself for insertion into and assembly with the rigid upper of the clog of the invention;

FIG. 6 is a cross-sectional view of the upper of the invention showing the manner in which the folded liner is inserted into the new clog and secured thereto; and

FIG. 7 is a cross-sectional view of the new and improved clog taken along line 7--7 of FIG. 3 and showing the folded lining of the new clog and the throat-like portions defined by said lining in accordance with the principles of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIG. 1, the new Dutch-type clog of the invention is indicated generally by the reference numeral 10 and includes a rigid upper 11 and a rigid lower 12, both of which advantageously may be carved out of separate solid blocks of wood, as indicated in the drawings, or, alternatively, both of which may be carved out of a single block of wood or injection molded as a single or two plastic components. Regardless of the number of elements or the material used to fabricate the upper and lower, the outer surfaces of the upper and lower are contiguous and the side edges are flush with one another to give the shoe the appearance of being formed from a single element, as, of course, is the case with a conventional "Dutch" shoe. That is to say, the upper 11 and the lower 12 appear to be integral, in accordance with the invention, whether or not they are, in fact, derived from a solid block of wood, two blocks of wood, or one or more plastic elements.

In the illustrated embodiment, the upper 11 and lower 12 are joined to one another by an adhesive 12 along a peripheral joint 14. To provide the clog, or at least the forwardmost portions thereof, with a general "Dutch shoe" or "Wooden shoe" appearance, the lower 12 is of thick dimension and defines a heel 15 and sole 16 separated by an arch 17. The upper surfaces 18 of the lower 12 are contoured and define an insole upon which the foot of the wearer will rest as will be understood. The upper 11, which is in the general nature of a hollow shell having side walls 19, 20 and a top wall 21, as shown best in FIG. 2, has an inverted U-shaped cross section. As will be understood, and may be appreciated by comparison of FIGS. 2 and 7, the shape and contour of the upper 11 varies along its length. The rearmost edges of the upper 11 are disposed in a plane which makes a blunt angle with the insole 18. As shown in the drawings, the upper terminates at the beginning of the heel portions 15 of the lower 12.

Advantageously and in accordance with well known shoemaking practice, the non-skid sole element 22 and a similar non-skid heel element 23, made of rubber or some other resilient wear material, may be appropriately secured to the lower as by nails or adhesive.

In accordance with an important feature of the invention, the backless clog 10 includes a liner 30 of resilient polyurethane foam which reduces the oversized foot cavity defined between the inner surfaces of the upper 11 and the insole 18 to a foot space which, by nature of the configuration and resiliency of the special liner 30, will snugly and comfortably accommodate all widths of a given foot size. More specifically, the liner 30 of the invention, as shown best in FIG. 4, is derived from a bell-shaped blank 31 of polyurethane foam which has its side edges effectively "skived" by a line of stitching 32 running adjacent a periphery thereof. The stitching 32 tends to compress and reduce the thickness of the peripheral portions of the blank 31 so that it may readily conform itself to the corners where the upper and lower meet. The remaining edge of the blank is reinforced and embraced by a leather collar 33 which is secured thereto by stitching 36. The collar 33 will provide a comfortable wear surface for the arched entrance to the shoe, as shown in FIG. 3, as well as providing a reduction in thickness of the liner immediately adjacent the opening to the shoe.

In accordance with principles of the invention, the rearmost portions of the upper 11 and the lining 30 associated therewith define a "keyhole" opening 35 having vertical dimensions which are greater than and horizontal dimensions which are less than the normal full width dimensions of the foot size for which the particular clog is intended. To that end, and as indicated in FIG. 7, the sizing and shaping of the upper 11 and the liner 30 are such that upon insertion of the liner into the shoe, in a manner to be described in greater detail hereinafter, the liner folds and is compressed along an asymmetrical axis 37 providing a foot opening specifically shaped for a left or a right foot. That is to say and referring to FIG. 7, the foot opening 35 in canted toward the instep side, providing a right shoe. In addition and as will be understood, the contour of the insole is also appropriately rightfooted or leftfooted for each shoe. In this manner, the "overstuffed" foam liner tends to lock the new clog onto the foot of the user by trapping the normal arch of the foot and the remaining portions of the foot between the contoured insole and the foam lining 30.

More specifically, since the foam lining 30 is "oversized," although it is resilient and deformable, it is necessary, in accordance with the principles of the invention, to rotate the foot of a user into a vertical or inclined plane to get the widest dimension of the foot through the narrow vertical opening or throat defined by "pillow" portions 38, 39 straddling the fold 37 and by the rearmost portions of the upper. Thereafter, when the widest part of the foot clears the throat and enters the wider portions of the upper disposed forwardly of the opening 35, it cannot be readily withdrawn by a rearward motion after it is returned to a horizontal plane. In other words and as shown in FIGS. 2 and 7, the rearmost portions of walls 19, 20 are more closely mutually spaced than intermediate wall portions. It should be understood that the height of the upper wall 21 or its spacing from the insole 18 is sufficient to accommodate insertion of a twisted foot having predetermined width dimensions, but the spacing of the rearmost portions of upper walls 19, 20 are less than that maximum dimension and do not accommodate the insertion or withdrawal of a foot in its normal flat position or horizontal position. Thus, this unique construction enables a clog to be held securely and comfortably on the foot of a user. Importantly, the "twist and straighten" entry and locking of the foot is facilitated immensely and the styling of the clog is accentuated by the elimination of a back.

In accordance with another aspect of the invention, the new foam lining is inserted in the rigid clog 10 by folding the blank 31 twice upon itself along the Y--Y and then along the X--X axes, as indicated in fig. 5, to form a compressed and four layer subassembly 40 generally having a heart-shaped profile (FIG. 5) which is sufficiently compact to be inserted into the mouth of the clog, as indicated in FIG. 6. Prior to the insertion of the subassembly 40 into the clog, the entrance arch 41 of the upper and other areas of the inner surfaces 11a of the upper may be coated with adhesive 42, as will be understood. Thereafter, the subassembly 40 is inserted into the upper and is opened down to the toe of the shoe, and the bead or skived edges opened into contact with the edges. The geometry and size of the liner will "overstuff" the shoe, as indicated in FIGS. 2, 3 and 7. The skived or effectively skived peripheral portions of the liner are adhered at the interface of the upper and lower along the joint 14, remaining contacting portions of the liner are adhered at the inner surfaces 11a of the upper 11, and the collar 33 is adhered to the arch 41. In accordance with the invention, since the blank 31 is oversized in terms of area, in comparison to the upper area 11a, the lining foam 30, as indicated in FIG. 7, will fold along axis 37 and form a narrow throat portion 35 bounded by pillow portions 38, 39. Beyond the throat are foot-receiving portions which will be leftfooted or rightfooted, depending upon the shape of the upper. The particular clog illustrated in the drawings is a rightfooted shoe. A mating left shoe would, of course, have a mirror image configuration of that shown in the drawings.

It should be understood that the clogs of the present invention may be varied slightly in shape and construction without departing from the principles of the present invention. As contemplated, the present construction accommodates the sizing of shoes in regular whole sizes, without any regard to width or to half-sizes, inasmuch as the resilient foam liners will accommodate any width of given shoe size and slight variations in length quite comfortably. By slightly varying the configuration of the upper and the overstuffed nature of the liner, it may be possible in certain cases to accommodate a series of whole sizes as well as a series of widths of feet for a given size clog. As presently contemplated, however, the above-described Dutch-type shoes are intended to be manufactured in regular shoe sizes, with regard to lengths, with each shoe size accommodating the normal range of foot widths. Thus, in the mass production of these shoes by automatic carving equipment or by injection molding equipment, it will only be necessary to tool up in a manner providing a single mold or single set of caving parameters for each foot size.

Claims

I claim:

1. A backless clog for a predetermined foot size comprising

a. a rigid, solid lower having contoured upper surfaces adapted to support the toes, ball, instep, and heel of a human foot of said predetermined size comfortably thereupon;

b. said lower having forward and rearward bottom surfaces definitive of an inflexible sole and an inflexible heel, respectively, separated by an arch;

c. a rigid hollow upper contiguous with the forward portions of said lower and cooperating therewith to define an arched foot opening;

d. the side edges of said upper and lower being flush and providing forwardmost portions of said clog with the general appearance of a one-piece "wooden" shoe;

e. said upper having contoured inner surfaces of predetermined area substantially larger than the area required to cover the forward portions of a foot of said predetermined foot size and cooperative with said lower to form an oversized liner receiving space;

f. a resilient foam liner means disposed in said liner receiving space and effectively reducing the same to a foot receiving space snugly accommodative of a foot of said predetermined size;

g. means securing said foam to said inner surfaces of said upper;

h. whereby said clog may be securely and comfortably held to the foot of the wearer by the snug enclosure of the forward portions of the foot by said foam, said upper, and said lower.

2. The clog of claim 1, in which

a. said liner is derived from a sheet of plastic foam material having an area greater than said predetermined area of the inner surfaces of said upper;

b. said liner thereby tending to be self-pleating upon insertion into said liner receiving space.

3. The clog of claim 2, in which

a. said liner is generally bell-shaped;

b. a reinforcing collar is secured to the rearward edges thereof.

4. The clog of claim 3, in which

a. said foam is expanded polyurethane;

b. said collar is a sheet material having the characteristics of leather.

5. The clog of claim 3, in which

a. the side edges of said liner are reduced in thickness.

6. The clog of claim 5, in which

a. a peripheral line of stitching extends about the side edges of said liner to form a reduced thickness bead.

7. The clog of claim 1, in which

a. said upper and said lower are separate elements.

8. The clog of claim 7, in which

a. said upper and lower are wood.

9. The clog of claim 1, in which

a. said upper and lower are injection molded plastic.

10. The clog of claim 1, which includes

a. a resilient, non-skid sole wear surface and a resilient, non-skid heel wear surface attached to the bottom surfaces of said sole and heel portions, respectively, of said lower.

11. The clog of claim 1, in which

a. said liner is definitive of a narrow, vertical "keyhole" type opening within said arched opening which may be entered by a foot disposed at an angle to the horizontal;

b. whereby said foot is adapted to be locked in said clog by the insertion of said foot thereinto with the sole thereof at an angle to the plane of said lower and the subsequent rotation of said foot into a plane generally parallel with that of said lower.

12. The clog of claim 11, in which

a. said "keyhole" opening is a narrow, vertical slot having a width dimension at the lowermost portions of said opening less than the maximum full width dimension of said predetermined foot size.

13. The clog of claim 1, in which

a. a separate collar means lines said arched foot opening.

14. The clog of claim 1, in which

a. the rear edges of said upper are in a plane defining an obtuse angle with the horizontal.

15. The clog of claim 14, in which

a. the rear edges of said upper terminate substantially short of the rear edges of said lower.

16. A method of manufacturing a clog for a predetermined foot size, including the steps of

a. shaping an upper and lower into a rigid, backless clog having the general appearance of a "wooden" shoe;

b. providing said clog with a liner cavity substantially larger than said foot size and having a narrow opening, said cavity being defined by the inner surfaces of said upper and top surfaces of said lower;

c. blanking a generally bell-shaped liner out of foam sheet material, the bell shape of the liner having a greater area than that of the inner surfaces of said upper;

d. folding said liner generally into quarters and inserting said liner into said cavity;

e. opening said liner in said cavity;

f. adhesively securing at least the rear edges of said liner to said inner surfaces in a manner whereby said liner is compressed along a fold axis straddled by two pillow-like portions definitive of a flexible, foot receiving cavity having a "keyhole" slot entrance through which a foot in a horizontal plane may not readily pass.

17. The method of claim 16, including the step of

a. reducing the peripheral edge thickness of said liner blank thickness.

18. The method of claim 16, including the step of

a. artificially skiving the peripheral edges of said liner blank by adding a line of stitching thereto.

19. The method of claim 16, further characterized in that

a. said upper and lower are wood.

20. The method of claim 16, further characterized in that

a. said upper and lower are plastic.

21. The method of claim 16, further characterized in that

a. said upper and lower are separate elements which are connected with their edges flush.