METHOD AND SYSTEM FOR AN ARTICLE OF FOOTWEAR WITH FUSED CONSTRUCTION

Abstract

A fused article of footwear and method are provided. The method of forming the fused article of footwear includes fitting an untrimmed welt ring to a cassette configured to hold the untrimmed welt ring spaced away from an outsole midsole unit of the fused article of footwear, aligning the cassette to a sole holder, positioning an upper in contact with the untrimmed welt ring to form a cavity and injecting plastic into the cavity defined by the untrimmed welt ring, the outsole midsole unit, the upper and the cassette to form a slip sole and fuse the untrimmed welt ring, the outsole midsole unit and the upper together.

Claims

1. A method of forming a fused article of footwear, comprising: fitting an untrimmed welt ring to a cassette, wherein the cassette is configured to circumferentially surround the fused article of footwear and includes a vertical portion and a ledge extending perpendicularly from the vertical portion towards an interior of the cassette, the ledge configured to hold the untrimmed welt ring spaced away from an outsole midsole unit of the fused article of footwear; aligning the cassette to a sole holder, wherein the sole holder includes a holding ring circumferentially surrounding the outsole midsole unit; positioning an upper in contact with the untrimmed welt ring to form a cavity; and injecting polymer into the cavity defined by the untrimmed welt ring, the outsole midsole unit, the upper, and the ledge of the cassette to form a slip sole and fuse the untrimmed welt ring, the outsole midsole unit, and the upper together.

2. The method of claim 1, wherein the untrimmed welt ring includes an outer flat portion and a radial width of the outer flat portion is longer than a distance that the ledge protrudes into the interior of the cassette.

3. The method of claim 1, wherein aligning the cassette to the sole holder includes placing an inner surface of the cassette in face sharing contact with an outer surface of the holding ring.

4. The method of claim 1, wherein the cassette is configured to flange the untrimmed welt ring up and in towards the upper.

5. The method of claim 1, wherein positioning the upper includes placing a lower edge of the upper in face sharing contact with a ridge portion of the untrimmed welt ring.

6. The method of claim 1, further comprising scuffing a lower edge of the upper before positioning the upper in contact with the untrimmed welt ring.

7. The method of claim 1, further comprising trimming the untrimmed welt ring to form a welt ring with edges flush to edges of the outsole midsole unit.

8. The method of claim 1, further comprising trimming a midsole flashing to form a midsole of the outsole midsole unit with edges flush to edges of an outsole and slip sole.

9. A fused article of footwear, comprising: an upper; a welt ring circumferentially surrounding a lower edge of the upper; an outsole midsole unit including a top portion formed of a midsole and a bottom portion formed of an outsole; and a slip sole fixedly positioned between the upper and the midsole and fused to the midsole, the welt ring, and the upper.

10. The fused article of footwear of claim 9, wherein the welt ring includes an outer flat portion and a ridge portion protruding from an inner edge of the outer flat portion, and wherein the lower edge of the upper is in face sharing contact with the ridge portion.

11. The fused article of footwear of claim 9, wherein the midsole includes a shank and/or a horseshoe positioned between the slip sole and the midsole.

12. The fused article of footwear of claim 9, wherein the welt ring is formed of thermoplastic polymer.

13. The fused article of footwear of claim 9, wherein the slip sole is formed of polyurethane.

14. The fused article of footwear of claim 9, wherein the welt ring includes stitching and wherein the stitching does not couple the welt ring to the upper or the outsole midsole unit.

15. A system for forming a fused article of footwear, comprising: a sole holder including a holding ring configured to hold an outsole midsole unit of the fused article of footwear and an outer surface circumferentially surrounding the holding ring; a cassette aligned with the sole holder, wherein a bottom edge of the cassette rests on the outer surface of the sole holder and the cassette holds an untrimmed welt ring spaced away from the outsole midsole unit; and an upper positioned above the cassette, wherein a lower edge of the upper is in face sharing contact with the untrimmed welt ring, wherein the outsole midsole unit, the cassette, the untrimmed welt ring, and the upper define a cavity configured to receive a plastic to fuse the fused article of footwear and form a slip sole.

16. The system of claim 15, wherein the sole holder is included in an injection molding machine.

17. The system of claim 15, wherein the upper is positioned on a last configured to be positioned by an injection molding machine.

18. The system of claim 15, wherein the cassette aligned with the sole holder circumferentially surrounds the sole holder.

19. The system of claim 15, wherein a ledge of the cassette is flush with an inner surface of the holding ring.

20. The system of claim 15, wherein the cavity is configured to receive the plastic at a heel end of the fused article of footwear.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0006] The present disclosure will be better understood from reading the following description of non-limiting embodiments, with reference to the attached drawings, wherein below:

[0007] FIG. 1 shows a side view of a fused article of footwear with fused construction.

[0008] FIG. 2 shows an exploded view of the fused article of footwear of FIG. 1.

[0009] FIG. 3 shows a side cross section view of the fused article of footwear of FIG. 1

[0010] FIG. 4 shows a flowchart of an example of a method for forming the fused article of footwear with fused construction.

[0011] FIG. 5 shows an example of a cassette used in the method of FIG. 4.

[0012] FIG. 6A shows an example of the cassette fitted with an untrimmed welt ring of the fused article of footwear during the method of FIG. 4.

[0013] FIG. 6B shows a cross section view of the untrimmed welt ring flanged by the cassette.

[0014] FIG. 7 shows an example of a sole holder used in the method of FIG. 4 for holding a bottom of the fused article of footwear.

[0015] FIG. 8 shows the cassette of FIG. 5 mated to the sole holder of FIG. 7.

[0016] FIG. 9A shows a cross sectional view of the fused article of footwear positioned relative to the sole holder and cassette during injection molding.

[0017] FIG. 9B shows a closer view of a portion of the cross sectional view of FIG. 9A.

DETAILED DESCRIPTION

[0018] The following description relates to a fused article of footwear having a fused construction, and a method and system for forming said article of footwear. A side view of an example fused article of footwear having a fused construction is shown in FIG. 1. The fused article of footwear may include an upper, a footbed, a welt ring, a slip sole, an outsole and a midsole as shown in exploded view of the article of footwear in FIG. 2 and the cross section side view in FIG. 3. A method of forming a fused article of footwear, such as the fused article of footwear shown in FIGS. 1-3 is shown in FIG. 4. The method may use a cassette to relatively position the components of the fused article footwear during polymer injection. An example of the cassette is shown in FIG. 5 and the cassette fitted with an untrimmed welt ring is shown in FIGS. 6A and 6B. A sole holder may hold an outsole midsole unit of the fused article of footwear in place as shown in FIG. 7 and may be mated to the cassette as shown in FIG. 8. During injection molding a cavity is defined in which the polymer is injected to form the slip sole. Positioning of the sole holder and cassette with respect to the cavity is shown in cross section in FIGS. 9A and 9B.

[0019] A set of reference axes 101 are provided for comparison between views shown, indicating a y-axis, a z-axis, and an x-axis. In some examples, the z-axis may be parallel with a direction of gravity when an outsole of an article of footwear is resting on the ground, with the x-axis and y-axis defining a horizontal plane. A direction extending from a lateral side to a medial side in the x-y plane may be referred to as a longitudinal direction. A direction extending perpendicular to the longitudinal direction from a toe end to a heel end may be referred to as a latitudinal direction.

[0020] Turning now to FIGS. 1-3 a side view, exploded side view, and a cross sectional side view respectively of a fused article of footwear 100 are shown. FIGS. 1-2 are described together. Fused article of footwear may include an upper 102. Upper 102 may be a flexible portion of the fused article of footwear configured to cover an upper portion of the user's foot. Upper 102 may be formed of a fabric. As one example, upper 102 may be formed of leather. Upper 102 may be configured to receive laces 104 which secure the fused article of footwear 100 to the user's foot. A heel of the user may be positioned towards heel end 103 of article of footwear 100 and a toe of the user may be positioned towards toe end 111 of the article of footwear.

[0021] The upper may include a footbed 105 which may fit inside and be coupled to a bottom (e.g., with respect to gravity) of upper 102. When wearing fused article of footwear 100, a bottom of a foot of the user may rest on an upper surface 107 of footbed 105. Edges of footbed 105 may be positioned inside upper 102 such that footbed 105 is shown in the exploded view of FIG. 2 but is not visible in the side view of FIG. 1. Footbed 105 may be formed of a polymer. For example, footbed 105 may be formed of polyurethane. The polyurethane may be poured polyurethane.

[0022] A welt ring 106 may circumferentially surround a lower (e.g., with respect to a direction of gravity) edge of upper 102. Welt ring 106 may include an outer flat portion 110 and a ridge portion 112. Ridge portion 112 may protrude from an inner (e.g., radially closer to upper 102 in the x-z plane) edge of outer flat portion 110. Ridge portion 112 may be in direct face sharing contact with upper 102. Stitches 108 may be positioned at an interface of outer flat portion 110 and ridge portion 112. Outer flat portion 110 and ridge portion 112 may be integrally formed. Stitches 108 may be decorative and may not couple to upper 102 or an outsole midsole unit 116 of the fused article of footwear. In some examples, welt ring 106 may not include stitches and/or may include other decorative elements or no decorative elements. Welt ring 106 may be formed of a thermoplastic polymer. For example, welt ring 106 may be formed of a thermoplastic polyurethane (TPU).

[0023] A lower side of welt ring 106 may be in face sharing contact with a slip sole 114. An upper side of slip sole 114 may be in face sharing contact with welt ring 106 and a bottom surface of footbed 105. Further, welt ring 106 may circumferentially surround slip sole 114. A lower side of slip sole 114 may be in face sharing contact with an outsole midsole unit 116. Slip sole 114 may be fixedly coupled to welt ring 106, outsole midsole unit 116, and the bottom surface of footbed 105. Slip sole 114 may be formed of a polymer (e.g., plastic). For example, slip sole 114 may be formed of polyurethane. In alternate examples, slip sole 114 may be formed of thermoplastic polyurethane. Slip sole 114 may be fused to welt ring 106, outsole midsole unit 116, footbed 105, and upper 102 of the fused article of footwear. In some examples, slip sole 114 may be fused to midsole 118 of outsole midsole unit 116. In this way, outsole midsole unit 116 may be fixedly coupled to footbed 105, upper 102, and to welt ring 106 via slip sole 114. Slip sole 114 may be formed by injection molding into a slip sole shaped cavity formed between the upper, the welt ring and the outsole midsole unit.

[0024] Outsole midsole unit 116 may include a midsole 118 and an outsole 120. Midsole 118 may form a top portion of outsole midsole unit 116 and may be sandwiched between slip sole 114 and outsole 120. Outsole 120 may form a bottom portion of the fused article of footwear 100 and may be configured to interface with the ground while the fused article of footwear 100 is being worn. In alternate examples, outsole midsole unit 116 may be a single continuous material and may not be divided into a midsole and outsole. An outline in the x-z plane of the upper surface of midsole 118, slip sole 114, and an outer circumference of welt ring 106 may be equivalent. The outer edges of midsole 118, slip sole 114, and welt ring 106 may be flush in the z-y plane. In some examples, outsole 120 or outsole midsole unit 116 may demand resoling. In such examples, outsole 120 and/or midsole 118 may be buffed and/or buffed away and a new outsole or outsole midsole unit may be attached. For example, the new outsole or outsole midsole unit may be attached by cement lamination.

[0025] Turning now to FIG. 3, a cross section side view of fused article of footwear 100 is shown. FIG. 3 shows slip sole 114 in face sharing contact with footbed 105, upper 102, and outsole midsole unit 116. A lower edge 202 of upper 102 may be the portion of upper 102 in face sharing contact with and fused to welt ring 106 and slip sole 114. In some examples, the fused article of footwear 100 may include a toe cap 302 formed of aluminum or carbon fiber. The midsole may include a shank 304 and/or a horseshoe 306, positioned between midsole 118 and slip sole 114. Slip sole 114 may be in face sharing contact with an upper surface of the shank 304 and/or horseshoe 306. Welt ring 106 may be vertically spaced away from outsole midsole unit 116. Welt ring 106 may not directly contact outsole midsole unit 116.

[0026] Turning now to FIG. 4, an example of a method 400 for forming a fused article of footwear, such as the fused article of footwear 100 described above with respect to FIGS. 1-3 is shown. Method 400 may, in some examples, be at least partially automated. At 402, method 400 includes positioning an upper assembly on a last. The upper assembly may include a footbed as described above with respect to FIGS. 1-3. The upper and footbed (e.g., upper 102 and footbed 105 of FIGS. 1-3) may be coupled together. For example, the footbed may be glued, stitched and/or otherwise attached to the upper. The last may be a last configured to hold an upper assembly on an injection molding machine.

[0027] At 403, method 400 optionally includes scuffing the lower edge of the upper. Scuffing the lower edge of the upper may include sanding, scraping or otherwise adding texture to the lower edge of the upper. In some examples, scuffing may be included in method 400 if the upper is formed of leather or other material which does not readily form a mechanical bond with the polymer and omitted if the upper is formed of other materials which do readily form a mechanical bond with the polymer. The lower edge of the upper may be the portion of the upper in face sharing contact with a welt ring and slip sole (e.g., welt ring 106 and slip sole 114 of FIGS. 1-3) when the fused article of footwear is formed, as shown in FIG. 3. Scuffing may increase an amount of surface area on the lower edge of the upper to help fuse the upper to the welt ring and slip sole.

[0028] At 404, method 400 includes fitting an untrimmed welt ring to a cassette. The cassette may be configured to hold the untrimmed welt ring position relative to and vertically spaced away from an outsole midsole unit (e.g., outsole midsole unit 116 of FIGS. 1-3) to define a cavity during injection molding in which the slip sole may be formed as described further below.

[0029] Turning briefly to FIGS. 5 and 6A-6B, an example of a cassette 500 used in method 400 is shown. The cassette may include a vertical portion 502. Vertical portion 502 may be shaped to circumferentially surround the sole of the fused article of footwear. Vertical portion 502 may have a first edge 504 configured to rest on a surface of a sole holder of an injection molding machine as described further below. Vertical portion 502 may extend between first edge 504 and a second edge 508 and include an inner face 506 configured to be in face sharing contact with the sole holder. Second edge 508, opposite the first edge 504 across the vertical (z) axis and also perpendicular to vertical portion 502 may be configured to support an untrimmed welt ring. Cassette 500 may further include a ledge 510. Ledge 510 may protrude from second edge 508 and may be perpendicular to vertical portion 502. Ledge 510 may protrude a distance 512 towards an interior of cassette 500.

[0030] FIG. 6A shows an untrimmed welt ring 602 fitted to cassette 500. Untrimmed welt ring 602 may rest on second edge 508 of vertical portion 502 and on ledge 510. Untrimmed welt ring 602 may include an outer flat portion 603 and a ridge portion 605. Untrimmed welt ring 602 may be circumferentially divided into a toc portion 602a and a mid to heel portion 602b. Line 606 may denote a dividing point between toe portion 602a and mid to heel portion 602b. Untrimmed welt ring 602 may be formed similarly to welt ring 106 of FIGS. 1-3 and ridge portion 605 may similarly protrude perpendicularly from an inner edge of outer flat portion 603. For example, untrimmed welt ring 602 may be precursor to welt ring 106. Radial width 604 of outer flat portion 603 may be reduced to form the welt ring 106 from untrimmed welt ring 602. Welt ring 106 may have edges flush with the sole after injection molding and trimming as described further below. Ledge 510 may protrude the distance 512 towards the interior of cassette 500. Radial width 604 of untrimmed welt ring 602 may be longer than distance 512. For this reason, when untrimmed welt 602 is fitted to cassette 500, an interior portion of untrimmed welt ring 602 which includes ridge portion 605 may extend past ledge 510. The extra width of outer flat portion 603 may provide a point of contact to cassette 500 allowing the inner portion to be suspended above and spaced away from the sole as described further below.

[0031] Cassette 500 may be configured to flange untrimmed welt ring 602 up towards the upper assembly and inward towards a radial center of cassette 500. Toe portion 602a may be flanged upward at a larger angle than mid to heel portion 602b. Turning now to FIG. 6B, a cross sections of toe portion 602a and mid to heel portion 602b are shown. A first cross section 650 shows toe portion 602a. Toe portion 602a may be flanged upward to tilt toe portion 602a at an angle towards an interior of untrimmed welt ring 602. A toe ridge tilt angle 652 of ridge portion 605 tilted away from vertical may be in a range from 4 to 30. In some examples, toe ridge tilt angle 652 may be in a range from 6 to 20. In some examples, toe ridge tilt angle 652 may be in a range from 6 to 10. Further a toe flat portion tilt angle 654 tilted away from horizontal may be in a range 1 to 45. In alternate examples, toe flat portion tilt angle 654 may be in range of 5 to 30. In further examples, toe flat portion tilt angle 654 may be in range of 10 to 20. In some examples, toe flat portion tilt angle 654 may be 15.

[0032] A second cross section 660 shows a cross section of mid to heel portion 602b. Mid to heel portion 602b may also be flanged upward toward to tilt mid to heel portion 602b towards an interior of untrimmed welt ring 602. A heel ridge tilt angle 662 may be tilted away from vertical at an 8 angle. Heel ridge tilt angle 662 may be smaller than toe ridge tilt angle 652. Further a heel ridge tilt angle 662 tilted away from horizontal may be in a range 1 to 45. In alternate examples, heel ridge tilt angle 662 may be in range of 2 to 20. In further examples, heel ridge tilt angle 662 may be in range of 5 to 12. In some examples, heel ridge tilt angle 662 may be 8.

[0033] A heel flat portion tilt angle 664 away from horizontal may be 15. In some examples, heel flat portion tilt angle 664 may be equivalent to toe flat portion tilt angle 654. Further a heel flat portion tilt angle 664 tilted away from horizontal may be in a range 1 to 45. In alternate examples, heel flat portion tilt angle 664 may be in range of 5 to 30. In further examples, heel flat portion tilt angle 664 may be in range of 10 to 20. In some examples, heel flat portion tilt angle may be 15.

[0034] Using cassette 500 to flange the untrimmed welt ring up and in may form an undercut between untrimmed welt ring 602 and the upper when the two are brought into face sharing contact during injection molding as described further below. There may be an undercut of toe portion 60a and an undercut of mid to heel portion 602b. The undercut of each may be the distance in the x-direction in which the untrimmed welt ring is shifted towards the upper assembly as a result of the flange caused by cassette 500. An undercut of toe portion 602a may be greater than an undercut of mid to heel portion 602b. For example, the undercut of toe portion 602a may be less than 2 times the undercut of mid to heel portion 602b. For example, the undercut of mid to heel portion 602b may be .sup.ths of the undercut of toe portion 602a. An extent of the undercut of toe portion 602a is indicated by bracket 656 and may be equal, in one example, to 0.8 mm. An extent of the undercut of mid to heel portion 602b is indicated by bracket 666 and may be 0.5 mm.

[0035] Untrimmed welt ring 602 may further include features configured to mate with features on cassette 500 to prevent untrimmed welt ring 602 from moving relative to cassette 500 during subsequent steps of method 400. The features may be positioned on a portion of untrimmed welt ring 602 that is trimmed away to leave behind the welt ring. For example, untrimmed welt ring 602 may include an indent 668 and a protrusion 670. Ledge 510 of cassette 500 may include complimentary features configured to mate with the features of untrimmed welt ring 602. For example, indent 668 may be mated to a corresponding protrusion on ledge 510 and protrusion 670 may be mated to a corresponding indent on ledge 510. In some examples, the portion of untrimmed welt ring 602 that is trimmed away may be vertically (e.g., in the z-direction) thinner than the rest of untrimmed welt ring 602. As one example, a thickness of a portion of untrimmed welt ring 602 including the mating features may be half the thickness of outer flat portion 603. As one example, the thickness of the trimmed portion may be 1.2 mm, as indicated by bracket 672.

[0036] Returning now to FIG. 4, method 400 proceeds to 406 and includes placing an outsole midsole unit of the fused article of footwear on a sole holder of the injection molding machine. The sole holder may circumferentially surround the outsole midsole unit and may be configured to prevent the outsole midsole unit from moving in the x or y directions during injection molding. The sole holder may be included in the injection molding machine. For example, the injection molding machine may move the sole holder vertically to help position the sole holder relative to the upper assembly positioned on the last. The outsole midsole unit may include both an outsole and midsole, such as outsole midsole unit 116 of FIGS. 1-3. The outsole midsole unit may be placed in the sole holder oriented with an outsole resting on a bottom of the sole holder and an upper surface of the midsole may be exposed for fusing to the upper and the untrimmed welt ring.

[0037] Turning briefly to FIG. 7, an example of an outsole midsole unit 706 placed in a sole holder 700 of the injection molding machine is shown. Sole holder 700 may include an outer surface 702 and a holding ring 704 protruding vertically from outer surface 702. Outsole midsole unit 706 (a non-limiting example of outsole midsole unit 116 of FIGS. 1-3) may be placed within holding ring 704. Holding ring 704 may circumferentially surround outsole midsole unit 706 and an inner surface of holding ring 704 may be in face sharing contact with sides of outsole midsole unit 706. An outsole of outsole midsole unit 706 may rest on a bottom surface of sole holder and a midsole of outsole midsole unit 706 may be facing upwards the last of the injection molding machine. The midsole portion of outsole midsole unit 706 may be the portion seen in FIG. 7. The midsole may include a shank 708 and horseshoe 710 (e.g., similar to shank 304 and horseshoe 306 of FIG. 3). The midsole may be an untrimmed midsole and may include midsole flashing 712. Midsole flashing 712 may rest on an upper edge of holding ring 704.

[0038] Returning now to FIG. 4, method 400 proceeds to 408 and includes aligning the cassette to the sole holder. The sole holder and cassette may be configured to mate together, such that inner surface of the cassette is in face sharing contact with an outer surface of the holding ring of the sole holder and bottom edge of the vertical portion of the cassette may rest on the outer surface of the sole holder. The midsole flashing may be sandwiched between the sole holder and the ledge of the cassette. In this way, the cassette is aligned to the sole holder and may hold the outsole midsole unit and the untrimmed welt ring in a desired position relative to each other. The cassette mated to the sole holder may hold the untrimmed welt ring spaced away from the outsole midsole unit thus defining the cavity which is filled by flowable polymer material (e.g., heated polymer, liquid polymer precursors, heated plastic material, or thermoplastic material) during injection molding to form the slip sole, as described further below.

[0039] Turning briefly to FIG. 8, an example of cassette 500 mated to a sole holder (e.g., sole holder 700 of FIG. 7) is shown. In some examples, cassette 500 may include baffles. As shown in FIG. 8, when mated, cassette 500 may be configured to hold untrimmed welt ring 602 vertically spaced away from outsole midsole unit 706.

[0040] Returning now to FIG. 4, method 400 proceeds to 410 and includes positioning the upper assembly on the last prepared at step 402 in contact with the untrimmed welt ring to form a cavity. The injection molding machine may automatically vertically position the upper and aligned cassette and sole holder within the injection mold such that the optionally textured lower edge of the upper is in face sharing contact with the ridge portion of the untrimmed welt ring. Because the cassette may flange the untrimmed welt ring upward and inward, the untrimmed welt ring may wrap to and pinch the upper. The cavity may be formed with a boundary defined by a portion of the ledge of the cassette, the untrimmed welt ring, a lower surface of the upper and an upper surface (e.g., midsole) of the outsole midsole unit.

[0041] Optionally, at 411, method 400 includes placing a mold release agent on top of the untrimmed welt ring. The mold release agent may help prevent the untrimmed welt from sticking to the injected polymer material (e.g., injected at step 412 as described further below). The mold release agent may be a non-stick material forming a non-stick barrier on the untrimmed welt ring to prevent undesired sticking of injected polymer material or other components of the injection process to the untrimmed welt ring. In one example, the mold release agent may be latex. In an alternate example, the mold release agent may be a polytetrafluoroethylene (e.g., Teflon).

[0042] At 412, method 400 includes injecting polymer, such as polyurethane, into the cavity to form a slip sole (e.g., slip sole 114) and fuse together the untrimmed welt ring, outsole midsole unit, and upper. In some examples, injecting polymer may include injecting polymer heated to be flowable. In alternate examples, injecting may include injecting flowable polymer precursors. A temperature of injection may depend on the polymer being injected. An injection time, injection speed and amount of polymer injected may depend on a size and model of the fused article of footwear being manufactured. For example, a size 12 article of footwear may use more polymer to form the slip sole than a size 8 fused article of footwear. Additionally or alternatively, the injection amount and/or the injection speed may be adjusted depending on a size of the fused article of footwear. The polymer may be injected between a heel end of the upper, outsole midsole unit assembly and the ridge portion of the untrimmed welt ring. Because boundaries of the cavity include surfaces of the untrimmed welt ring, the upper and the outsole midsole unit, when the injected polymer sets to form the slip sole and it fuses the welt ring and upper together and fuses each of the welt ring and upper to the outsole midsole unit via the slip sole. The wrapping and pinching of the untrimmed welt ring to the upper as described above may cap a vertical flow (e.g., in the z direction) of the injected polymer within the cavity. The flashing portion of the midsole may be held in face sharing contact with the inner surface of cassette 500 to help cap planar flow (e.g., in the x-y plane) of the injected polymer within the cavity.

[0043] Turning briefly to FIGS. 9A and 9B, it shows a cross section of the upper and mated sole holder 700 and cassette 500 after injection of the polymer to form slip sole 904. For injecting, mated sole holder 700 and cassette 500 as well as a lower portion of upper 902 may be positioned within bottom plate tooling 908 of the injection molding machine. Bottom plate tooling 908 may help guide the polymer into the cavity to form slip sole 904. Mated sole holder 700 and cassette 500 position and support the untrimmed welt ring 602 in position with respect to outsole midsole unit 706, while the last holds upper 902 at the desired position with respect to untrimmed welt ring 602. An inner edge of ledge 510 of the cassette may be flush in the z-y plane to an inner surface of holding ring 704. Slip sole 904 (e.g., similar to slip sole 114 of FIGS. 1-3) is formed in the cavity described above. In this way, slip sole 904 is in face sharing contact and fused with upper 902, untrimmed welt ring 602, outsole midsole unit 706. Slip sole 904 may also be in face sharing contact with the inner surface of cassette 500, but cassette 500 may be formed of a material that does not fuse to injected polymer forming slip sole 904 (e.g., polyurethane). Further, cassette 500 and sole holder 700 are configured to be easily removed from the fused article of footwear after injection molding.

[0044] Returning now to FIG. 4, method 400 proceeds to 414 and includes removing the fused article of footwear from the injection molding machine and trimming the untrimmed welt ring and midsole flashing. For example, removing includes moving the fused article of footwear in one direction and the sole holder and cassette may be moved in the opposite direction to separate the two. No additional tools or undoing of fasteners may be demanded to unmate cassette 500 and sole holder 700 or to remove the fused article of footwear from cassette 500 and sole holder 700. Trimming the untrimmed welt may include trimming the excess material of the outer flat portion of the untrimmed welt ring 602 to form a welt such as welt ring 106 where an outer edge of the welt is flush with radially outer edges of the slip sole and the outsole midsole unit as shown in the example of fused article of footwear 100 of FIGS. 1-3. Trimming the midsole flashing may include trimming the midsole flashing to make radially outer edges of midsole 118 flush with radially outer edges of the slip sole and the welt ring. Trimming the midsole flashing may also include trimming a slip sole flashing. The slip sole flashing may form by a small leakage of injected polymer between the cassette ledge and an upper edge of the sole holder. The slip sole flashing may be formed of similar material as the midsole flashing. Method 400 ends.

[0045] Returning briefly to FIG. 9A, dashed line 906 indicates where untrimmed welt ring 602, slip sole flashing and midsole flashing are trimmed to form welt ring 106. An area 910 is shown at a larger scale in FIG. 9B. Slip sole flashing 912 and midsole flashing 712 are shown positioned between ledge 510 of cassette 500 and holding ring 704 of sole holder 700. Both may be trimmed away at dashed line 906 along with the excess portion of untrimmed welt ring 602. A vertical thickness 914 of slip sole flashing 912 and a vertical thickness 916 of midsole flashing 712 may each be 0.5 mm. In some examples, slip sole 904 and midsole 118 may be formed of similar material and may be trimmed together in one step. In some examples, untrimmed welt ring 602 may be formed of a different material than slip sole 904 and midsole 118 and trimming midsole flashing 712 and slip sole flashing 912 may be done in a separate step from trimming untrimmed welt ring 602.

[0046] The technical effect of method 400 is to produce a fused article of footwear including a welt ring by injecting a polymer to fuse the welt ring, upper, and a sole of the footwear together. In this way a single, easily automated step that produces a minimal amount of waste is used to assemble the fused article of footwear. Further, a system using an untrimmed welt ring supported by a cassette configured to mate to a sole holder enables the formation of a cavity to receive the polymer to form the slip sole to fuse the fused article of footwear.

[0047] The disclosure also provides support for a method of forming a fused article of footwear, comprising: fitting an untrimmed welt ring to a cassette, wherein the cassette is configured to circumferentially surround the fused article of footwear and includes a vertical portion and a ledge extending perpendicularly from the vertical portion towards an interior of the cassette, the ledge configured to hold the untrimmed welt ring spaced away from a outsole midsole unit of the fused article of footwear, aligning the cassette to a sole holder, wherein the sole holder includes a holding ring circumferentially surrounding the outsole midsole unit, positioning an upper in contact with the untrimmed welt ring to form a cavity, and injecting polymer into the cavity defined by the untrimmed welt ring, the outsole midsole unit, the upper, and the ledge of the cassette to form a slip sole and fuse the untrimmed welt ring, the outsole midsole unit, and the upper together. In a first example of the method, the untrimmed welt ring includes an outer flat portion and a radial width of the outer flat portion is longer than a distance that the ledge protrudes into the interior of the cassette. In a second example of the method, optionally including the first example, aligning the cassette to the sole holder includes placing an inner surface of the cassette in face sharing contact with an outer surface of the holding ring. In a third example of the method, optionally including one or both of the first and second examples, the cassette is configured to flange the untrimmed welt ring up and in towards the upper. In a fourth example of the method, optionally including one or more or each of the first through third examples, positioning the upper includes placing a lower edge of the upper in face sharing contact with a ridge portion of the untrimmed welt ring. In a fifth example of the method, optionally including one or more or each of the first through fourth examples, the method further comprises: scuffing a lower edge of the upper before positioning the upper in contact with the untrimmed welt ring. In a sixth example of the method, optionally including one or more or each of the first through fifth examples, the method further comprises: trimming the untrimmed welt ring to form a welt ring with edges flush to edges of the outsole midsole unit. In a seventh example of the method, optionally including one or more or each of the first through sixth examples, the method further comprises: trimming a midsole flashing to form a midsole of the outsole midsole unit with edges flush to edges of an outsole and slip sole.

[0048] The disclosure also provides support for a fused article of footwear, comprising: an upper, a welt ring circumferentially surrounding a lower edge of the upper, an outsole midsole unit including a top portion formed of a midsole and a bottom portion formed of an outsole, and a slip sole fixedly positioned between the upper and the midsole and fused to the midsole, the welt ring, and the upper. In a first example of the system, the welt ring includes an outer flat portion and a ridge portion protruding from an inner edge of the outer flat portion, and wherein the lower edge of the upper is in face sharing contact with the ridge portion. In a second example of the system, optionally including the first example, the midsole includes a shank and/or a horseshoe positioned between the slip sole and the midsole. In a third example of the system, optionally including one or both of the first and second examples, the welt ring is formed of thermoplastic polymer. In a fourth example of the system, optionally including one or more or each of the first through third examples, the slip sole is formed of polyurethane. In a fifth example of the system, optionally including one or more or each of the first through fourth examples, the welt ring includes stitching and wherein the stitching does not couple the welt ring to the upper or the outsole midsole unit.

[0049] The disclosure also provides support for a system for forming a fused article of footwear, comprising: a sole holder including a holding ring configured to hold an outsole midsole unit of the fused article of footwear and an outer surface circumferentially surrounding the holding ring, a cassette aligned with the sole holder, wherein a bottom edge of the cassette rests on the outer surface of the sole holder and the cassette holds an untrimmed welt ring spaced away from the outsole midsole unit, an upper positioned above the cassette, wherein a lower edge of the upper is in face sharing contact with the untrimmed welt ring, wherein the outsole midsole unit, the cassette, the untrimmed welt ring, and the upper define a cavity configured to receive a plastic to fuse the fused article of footwear and form a slip sole. In a first example of the system, the sole holder is included in an injection molding machine. In a second example of the system, optionally including the first example, the upper is positioned on a last configured to be positioned by an injection molding machine. In a third example of the system, optionally including one or both of the first and second examples, the cassette aligned with the sole holder circumferentially surrounds the sole holder. In a fourth example of the system, optionally including one or more or each of the first through third examples, a ledge of the cassette is flush with an inner surface of the holding ring. In a fifth example of the system, optionally including one or more or each of the first through fourth examples, the cavity is configured to receive the plastic at a heel end of the fused article of footwear.

[0050] It will be appreciated that the configurations and/or approaches described herein are exemplary in nature, and that these specific embodiments or examples are not to be considered in a limiting sense, because numerous variations are possible. The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various features, functions, acts, and/or properties disclosed herein, as well as any and all equivalents thereof.

[0051] FIGS. 1-3 and 5-9B show example configurations with relative positioning of the various components. If shown directly contacting each other, or directly coupled, then such elements may be referred to as directly contacting or directly coupled, respectively, at least in one example. Similarly, elements shown contiguous or adjacent to one another may be contiguous or adjacent to each other, respectively, at least in one example. As an example, components laying in face-sharing contact with each other may be referred to as in face-sharing contact. As another example, elements positioned apart from each other with only a space there-between and no other components may be referred to as such, in at least one example. As yet another example, elements shown above/below one another, at opposite sides to one another, or to the left/right of one another may be referred to as such, relative to one another. Further, as shown in the figures, a topmost element or point of element may be referred to as a top of the component and a bottommost element or point of the element may be referred to as a bottom of the component, in at least one example. As used herein, top/bottom, upper/lower, above/below, may be relative to a vertical axis of the figures and used to describe positioning of elements of the figures relative to one another. As such, elements shown above other elements are positioned vertically above the other elements, in one example. As yet another example, shapes of the elements depicted within the figures may be referred to as having those shapes (e.g., such as being circular, straight, planar, curved, rounded, chamfered, angled, or the like). Further, elements shown intersecting one another may be referred to as intersecting elements or intersecting one another, in at least one example. Further still, an element shown within another element or shown outside of another element may be referred as such, in one example. Elements offset from one another may be referred to as such, in some examples. FIGS. 1-3 and 5-9B are shown to scale, however, other dimensions may be used if desired

[0052] As used herein, an element or step recited in the singular and preceded with the word a or an should be understood as not excluding plural of said elements or steps, unless such exclusion is explicitly stated. Furthermore, references to one embodiment of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments comprising, including, or having an element or a plurality of elements having a particular property may include additional such elements not having that property. The terms including and in which are used as the plain-language equivalents of the respective terms comprising and wherein. Moreover, the terms first, second, and third, etc. are used merely as labels, and are not intended to impose numerical requirements or a particular positional order on their objects.

[0053] This written description uses examples to disclose the invention, including the best mode, and also to enable a person of ordinary skill in the relevant art to practice the invention, including making and using any articles, devices, or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those of ordinary skill in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.