This nonprovisional application is based on Japanese Patent Application No. 2021-041707 filed on Mar. 15, 2021 and No. 2020-077796 filed on Apr. 24, 2020, with the Japan Patent Office, the entire contents of which are hereby incorporated by reference.
The present disclosure relates to a last, a method for manufacturing a last, and a method for manufacturing a footwear upper.
When producing an article of footwear, a last (or a footwear model) for being covered with a cloth configuring a footwear upper is used in order to form the footwear upper into a predetermined shape.
U.S. Patent Application Publication No. 2018/0014609 discloses manufacturing an article of footwear in a portable housing. US 2016/0206049 discloses a last preform reformable with a shape memory polymer. Chinese Patent No. 109732913 discloses forming a last by 3D printing.
When making a made-to-order article of footwear fitting a user's feet, a dedicated last reflecting the shape of the feet of each individual is produced. Manufacturing a user-dedicated last in a conventional manner employs dedicated large-size equipment and requires time and cost.
The present disclosure proposes a user-dedicated last that can be easily manufactured without using large-scale equipment, a method for manufacturing the last, and a method for manufacturing a footwear upper using the last.
According to an aspect of the present disclosure, a last for forming a footwear upper configuring an article of footwear is proposed. The last comprises a foot length forming member that defines a shape of the last at least in a lengthwise direction of the article of footwear, and a plurality of foot width forming members that define a shape of the last at least in a widthwise direction of the article of footwear and are assembled to the foot length forming member.
According to an aspect of the present disclosure, a method for manufacturing a last for forming a footwear upper configuring an article of footwear is proposed. The method for manufacturing a last comprises the following steps. A first step is a step of preparing a foot length forming member that defines a shape of the last at least in the lengthwise direction of the article of footwear, and a plurality of foot width forming members that define a shape of the last at least in the widthwise direction of the article of footwear. A second step is a step of assembling the foot width forming member to the foot length forming member.
According to an aspect of the present disclosure, a method for manufacturing a footwear upper is proposed. The present method for manufacturing a footwear upper comprises the following steps. A first step is a step of covering the above-mentioned last with an unformed upper made of a fiber sheet including a heat-shrinkable yarn. A second step is a step of applying heat to form the unformed upper along the shape of the last to be a formed upper.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
Hereinafter, embodiments will be described with reference to the drawings. In the following description, identical components are identically denoted. Their names and functions are also identical. Accordingly, such components will not be described repeatedly.
A last (or a footwear model) of an embodiment described below is mainly a last for a made-to-order article of footwear made to fit a user's foot. It should be noted, however, that the last of the embodiment is also applicable to a last for articles of footwear in mass production.
Foot model FM may be formed in the same shape as the user's foot F. Alternatively, for some reason in design or functionality, foot model FM may have a specific portion corrected from the shape of the user's foot F by a desired dimension.
Note that in the present specification, a lengthwise direction refers to a direction along a straight line connecting a foremost end on a toe side and a rearmost end on a heel side when an article of footwear or a last is seen in plan view. A widthwise direction refers to a direction orthogonal to the lengthwise direction in plan view. A heightwise direction refers to a direction orthogonal to a plane defined by the lengthwise direction and the widthwise direction.
Cross-sectional last model 110 is formed as a combination of a plurality of foot length forming models 120 extending in the lengthwise direction and a plurality of foot width forming models 140 extending in the widthwise direction.
As shown in
By processing base member 10 along foot length forming model 120 and foot width forming model 140 disposed on base member 10, parts of the last, more specifically, foot length forming member 20 and foot width forming member 40 described below, are formed. For example, foot length forming member 20 and foot width forming member 40 may be formed by cutting them out of base member 10 with a laser cutter or the like. Foot length forming member 20 and foot width forming member 40 formed from a single base member 10 are each in the form of a plate and equal in thickness.
Base member 10 is in the form of a flat plate and foot length forming member 20 is formed as it is cut out of base member 10, and accordingly, foot length forming member 20 is also in the form of a plate. Foot length forming member 20 extends in the lengthwise direction of the last. Foot length forming member 20 defines a shape of the last at least in the lengthwise direction. Foot length forming member 20 defines a shape of the last in the lengthwise direction and the heightwise direction.
Foot length forming member 20 has a plurality of engagement grooves 30 formed therein. Engagement grooves 30 are aligned at equal intervals in the lengthwise direction. Each engagement groove 30 is in the form of a slit extending in the heightwise direction. Engagement groove 30 extends downward from an upper edge of foot length forming member 20. Engagement groove 30 has an opening 31 that opens at the upper edge of foot length forming member 20, and has a bottom 32 at an intermediate position that does not reach a lower edge of foot length forming member 20. As shown in
Base member 10 is in the form of a flat plate and foot width forming member 40 is formed as it is cut out of base member 10, and accordingly, foot width forming member 40 is also in the form of a plate. Foot width forming member 40 extends in the widthwise direction of the last. Foot width forming member 40 defines a shape of the last at least in the widthwise direction. Foot width forming member 40 defines a shape of the last in the widthwise direction and the heightwise direction. Foot width forming member 40 shown in
Foot width forming member 40 has a plurality of engagement grooves 50 formed therein. Engagement grooves 50 are aligned at equal intervals in the widthwise direction. Each engagement groove 50 is in the form of a slit extending in the heightwise direction. Engagement groove 50 extends upward from a lower edge of foot width forming member 40. Engagement groove 50 has an opening 51 that opens at the lower edge of foot width forming member 40, and has a bottom 52 at an intermediate position that does not reach an upper edge of foot width forming member 40. Engagement groove 50 may have a length that is half a length from the upper edge to the lower edge of foot width forming member 40 at a position where engagement groove 50 is formed. As shown in
Since foot length forming member 20 has engagement grooves 30 formed at equal intervals in the lengthwise direction, the plurality of foot width forming members 40 are equally spaced in the lengthwise direction. Since foot width forming member 40 has engagement grooves 50 formed at equal intervals in the widthwise direction, the plurality of foot length forming members 20 are equally spaced in the widthwise direction.
Position identifier 60 has character information “L” indicating that foot width forming member 40 is a part of last 1 for a left foot, character information “H” indicating that foot width forming member 40 is foot width forming member 40, and character information “6” indicating that foot width forming member 40 is a sixth part as counted from a toe. Position identifier 60 has a mark. By matching the mark in direction, foot width forming member 40 can face in a correct direction, position identifier 60 is observable, and each piece of character information can be recognized correctly.
Position identifier 60 shown in
Position identifier 60 is not limited to the above-described examples. For example, coloring engagement groove 30 of foot length forming member 20 and foot width forming member 40 to be assembled to engagement groove 30, and combining the same colors, allow an appropriate foot width forming member 40 to be assembled in an appropriate engagement groove 30.
While foot length forming member 20 and foot width forming member 40 may be assembled manually, they may be assembled automatically by a robot. The robot reads the positional information of foot length forming member 20 and foot width forming member 40 recorded in position identifier 60 and recognizes a position of position identifier 60 in foot length forming member 20 and foot width forming member 40, and thus ensures that foot length forming member 20 and foot width forming member 40 are each assembled in an appropriate position and an appropriate orientation.
Hereinafter, although there will be a description partially overlapping with the above description, a characteristic configuration as well as function and effect of the present embodiment will be listed below.
As shown in
Based on foot model FM of a target user, foot length forming member 20 and foot width forming member 40 are prepared by cutting them out of sheet-shaped base member 10. Foot width forming member 40 is assembled to foot length forming member 20 to form last 1. No large-scale equipment is required to prepare foot length forming member 20 and foot width forming member 40 and assemble foot width forming member 40 to foot length forming member 20. Thus, last 1 dedicated to the target user can be easily manufactured.
As shown in
As shown in
As shown in
As shown in
Instead of tapered portions 33 and 53, engagement grooves 30 and 50 may be provided with a different engagement means such as a protrusion. Engagement grooves 30 and 50 having their respective, internal protrusions engaged with each other can suppress disengagement of foot length forming member 20 and foot width forming member 40 and also allow foot length forming member 20 and foot width forming member 40 to be correctly assembled together.
As shown in
As shown in
Incorporating foot length forming member 20 and foot width forming member 40 into a packing material allows a user to bring foot length forming member 20 and foot width forming member 40 back to home. The user can assemble last 1 at home, and can use it when ordering the same article of footwear next time, use last 1 that is assembled as a shoe tree, store it as a child's growth record, etc.
As shown in
In the above description of the embodiment, an example has been described in which foot length forming member 20 and foot width forming member 40 are formed by cutting them out of base member 10. Foot length forming member 20 and foot width forming member 40 are not limited to being cut out of base member 10 in the form of a plate, and may be formed in other methods such as using a 3D printer.
Last 1 shown in
Last 1 of the second embodiment has adjacent foot width forming members 40 spaced narrower in the middle foot portion than in the front foot portion. The front foot portion has a small variation in foot shape for each user, and the middle foot portion has a relatively large variation in foot shape for each user. Reducing a spacing between adjacent foot width forming members 40 in the middle foot portion that tends to have a difference in foot shape for each user allows last 1 to have a middle foot portion having a shape with improved accuracy.
Thus increasing/decreasing a spacing between foot width forming members 40 in the lengthwise direction allows last 1 to be produced to reflect the user's foot shape with high accuracy. Since a spacing between foot width forming members 40 in the front and rear foot portions that are less likely to have a difference in foot shape for each user is not excessively reduced, the number of parts is suppressed, and last 1 can be manufactured faster.
When the middle foot portion has foot width forming member 40 small in thickness, the middle foot portion can have adjacent foot width forming members 40 easily spaced narrower. This can further improve accuracy in shape of the middle foot portion of last 1, and last 1 can be produced to reflect the shape of the foot of the user with higher accuracy.
As shown in
By forming foot length forming member 20 in the form of a rod, forming throughhole 42 through plate-shaped foot width forming member 40, and passing rod-shaped foot length forming member 20 through throughhole 42, foot width forming member 40 can be assembled to foot length forming member 20. Thus, foot length forming member 20 and foot width forming member 40 can be assembled more easily and faster than in the first embodiment.
Last 1 can be easily disassembled by pulling foot length forming member 20 out of foot width forming member 40 through throughhole 42. This facilitates recycling foot width forming member 40. Foot length forming member 20 may be made of paper or resin and recycled in the same manner as foot width forming member 40, or foot length forming member 20 may be reused as it is.
When rod-shaped foot length forming member 20 is passed through throughhole 42 of foot width forming member 40, managing a dimension of a gap between adjacent foot width forming members 40 is required. By disposing spacer 24 between adjacent foot width forming members 40 separately from foot length forming member 20, a position where foot width forming member 40 is assembled with respect to foot length forming member 20 can be controlled. Foot width forming members 40 can thus be spaced as specified. For example, forming all spacers 24 identically in shape allows foot width forming members 40 to be equally spaced, and applying short spacer 24 to the middle foot portion can reduce a spacing between foot width forming members 40.
Last 1 shown in
When throughhole 42 is formed in plate-shaped foot width forming member 40, throughhole 42 can be burred to circumferentially have a cylindrical wall to form a structure in which foot width forming member 40 and spacer 24 are integrated together. In this case, last 1 shown in
Base portion 26 has a shape corresponding to that of an upper surface of a footwear sole to which a footwear upper is bonded. Core portion 28 has a three-dimensional shape obtained by reducing last model 100 (see
Last 1 is thus formed by fitting foot width forming member 40 into core portion 28 having a three-dimensional shape. Foot width forming member 40 can thus be easily assembled to foot length forming member 20. An area of foot width forming member 40 formed in accordance with the user's foot shape is reduced, and accordingly, an area of base member 10 used to cut out foot width forming member 40 can be reduced, and a user-dedicated last can be efficiently manufactured with a small amount of material. Engagement groove 30 formed in core portion 28 extends along a surface of core portion 28 having a three-dimensional shape and thus has the same curvature as the surface of core portion 28, and last 1 can achieve high reproducibility for a shape of a foot of a user.
Last 1 shown in
That is, foot length forming member 20 does not necessarily define the shape of last 1 along the entire length of last 1 in the lengthwise direction. Foot length forming member 20 may be any such member that defines a shape of at least a portion of last 1 at least in the lengthwise direction. Similarly, foot width forming member 40 does not necessarily define the shape of last 1 along the entire width of last 1 in the widthwise direction. Foot width forming member 40 may be any such member that defines a shape of at least a portion of last 1 at least in the widthwise direction.
Thus, last 1 using common portion 70 at a portion which is less likely to provide a difference in foot shape for each user and does not need to change last 1 in shape and position can have a reduced number of parts to be assembled and can hence be assembled in a reduced period of time. Forming a portion that provides a large difference in foot shape for each user and thus significantly affects an article of footwear in fitness by a combination of foot length forming member 20 and foot width forming member 40 exclusively for the user allows the user's foot shape to be better reproduced.
Using movable portion 80 at a portion where users are less likely to have a difference in shape while having a positional difference allows last 1 to be assembled in a reduced period of time. Simply positionally modifying an existing part allows last 1 to be adjusted in shape to match a shape of a foot of a user.
With reference to
The movable portion for the heel portion may also be movable in the heightwise direction in addition to the lengthwise and widthwise directions. The movable portion for the heel portion may be angularly variable with respect to common portion 70. In this case, a cavity may be formed above and/or below the movable portion for the heel portion for allowing movement of the movable portion. After the movable portion is positionally adjusted, the cavity may be filled with any filler. The filler may be shaped to match the shape of the user's foot F.
When a footwear sole is formed in a mold, the footwear sole has a fixed shape regardless of a shape of a foot of a user. A bottom surface of a footwear upper that is bonded to the footwear sole has a fixed shape regardless of a shape of a foot of a user. As the footwear upper has the bottom surface fixed in shape, last 1 for forming the footwear upper also has a bottom surface fixed in shape. Accordingly, last 1 having a bottom surface portion in a shape that is common portion 70 can be stabilized in shape.
When last 1 is covered with cover 90, last 1 of the embodiment can be used to form a footwear upper while suppressing an effect that a gap formed between foot length forming member 20 and foot width forming member 40 has on a shape that the footwear upper has after it is formed. This further ensures that the footwear upper is formed to have a predetermined shape.
Cover 90 may be a film that shrinks when it is heated, such as polystyrene film. In this case, last 1 can be covered with the film, which can in turn be heated and thus deformed to form cover 90 to cover a surface of last 1. In thermally deforming cover 90, (warm) air may be sent from the inside of cover 90. This can suppress excessive inward shrinkage of cover 90 between adjacent foot length forming members 20 and adjacent foot width forming members 40 and can further increase accuracy in forming a footwear upper.
Cover 90 may be metal foil represented by aluminum foil, and in this case, covering a surface of last 1 with metal enhances thermal conductivity, which is advantageous in heating and thus forming a footwear upper, as will be described hereinafter. Alternatively, cover 90 may be a sock.
As shown in
Cap 92 allows last 1 to have a smoothly curved external surface. When last 1 is used to form a footwear upper, cap 92 can prevent an end surface of foot length forming member 20 and/or foot width forming member 40 from being transferred to the footwear upper and prevent a gap between foot length forming member 20 and foot width forming member 40 from affecting the shape of the footwear upper. This further ensures that the footwear upper is formed to have a predetermined shape.
Last 1 of the tenth embodiment is characterized by a configuration of foot width forming member 40 at a portion corresponding to a heel portion of a foot. Specifically, at the portion corresponding to the heel portion of the foot, foot width forming members 40 are aligned in the heightwise direction of last 1. In the heel portion of last 1, foot length forming member 20 has formed therein a plurality of engagement grooves 30 aligned at equal intervals in the heightwise direction. In the heel portion of last 1, a plurality of foot width forming members 40 are assembled in engagement grooves 30 and thus aligned at equal intervals in the heightwise direction. It should be noted that the pitch of the plurality of foot width forming members 40 may be fixed or changed to be smaller for a portion which requires accuracy, in particular, than other portions.
A radial engagement groove 50 is formed in each of foot width forming members 40 in the heel portion. A plate-shaped engagement member 44 extending in the heightwise direction is assembled in radial engagement groove 50. Combining a plurality of foot width forming members 40 and a plurality of engagement members 44 in the form of a grid enhances the heel portion of last 1 in strength.
The heel portion has a relatively large variation in foot shape for each user. In addition, when the heel portion is compared with other portions, the former has a surface of a foot having protrusion and depression with significant variation in shape. A plurality of foot width forming members 40 aligned in the heightwise direction can reproduce a shape of a foot better than using foot width forming member 40 that extends in the heightwise direction to form a heel portion of last 1. This can further improve accuracy in shape of last 1, and last 1 can be produced to reflect the shape of the foot of the user with higher accuracy.
In an eleventh embodiment will be described one example of a method for manufacturing a footwear upper using last 1 described in the above embodiments.
Through such a manufacturing process, a footwear upper matching a user's foot F in shape and thus dedicated to the user can be manufactured without using large-scale equipment.
Heating box 210 may be a steam oven. While unformed upper 200 is heated with steam, unformed upper 200 may be heated with hot air, warm water or the like. Unformed upper 200 may be heated partially rather than entirely. The thus formed upper is attached to a separately formed footwear sole through adhesion, thermal fusion bonding, or the like.
While each step is performed or after the whole process is completed, a footwear tongue is formed, a footwear opening is processed, eyelets are attached for passing a footwear lace therethrough, an ornament and a tag are attached, a logo is printed, an insole is attached and the like to manufacture an article of footwear.
The method for manufacturing the footwear upper is not limited to thermal shrinkage of a fiber sheet including a heat-shrinkable yarn, as described above, and a variety of methods may be employed, for example, knitting a material around last 1 directly, additive manufacturing with a 3D printer, or the like. It is also possible to use last 1 of the embodiments in a conventionally known process of forming a footwear upper in a factory.
The characteristic configurations disclosed in the above-described embodiments and modifications thereof will be summarized as follows.
A last according to an embodiment of the present disclosure is directed to forming a footwear upper configuring an article of footwear. The last comprises a foot length forming member that defines a shape of the last at least in a lengthwise direction of the article of footwear, and a plurality of foot width forming members that define a shape of the last at least in a widthwise direction of the article of footwear and are assembled to the foot length forming member.
In a last according to an embodiment of the present disclosure, at least one of the foot length forming member and the foot width forming member may have a position identifier that indicates a position of the foot length forming member and the foot width forming member in the last.
In a last according to an embodiment of the present disclosure, a plurality of foot width forming members may be aligned in the lengthwise direction, and adjacent foot width forming members may be spaced narrower in a middle foot portion of the last than in a front foot portion of the last.
In a last according to an embodiment of the present disclosure, the foot width forming member may be in the form of a plate, a plurality of foot width forming members may be aligned in the lengthwise direction, and the foot width forming member may be smaller in thickness in the middle foot portion of the last than in the front foot portion of the last.
A last according to an embodiment of the present disclosure may have a heel portion with a plurality of foot width forming members aligned in the heightwise direction.
In a last according to an embodiment of the present disclosure, the foot length forming member may be in the form of a rod extending in the lengthwise direction and the foot width forming member may have a throughhole formed therein to pass the foot length forming member therethrough.
A last according to an embodiment of the present disclosure may have a plurality of foot width forming members aligned in the lengthwise direction and may further comprise a spacer disposed between adjacent foot width forming members to define a spacing between the adjacent foot width forming members.
In a last according to an embodiment of the present disclosure, the foot length forming member may be in the form of a plate.
In a last according to an embodiment of the present disclosure, the foot length forming member may have a hollow or solid three-dimensional shape.
In a last according to an embodiment of the present disclosure, the foot length forming member may have an engagement groove, and the foot width forming member may be assembled to the engagement groove.
In a last according to an embodiment of the present disclosure, the foot width forming member may have a second engagement groove, the foot length forming member may be assembled to the second engagement groove, and the engagement groove and the second engagement groove may each have a tapered portion allowing the groove to have a width reduced as it approaches the bottom of the groove.
In a last according to an embodiment of the present disclosure, the foot length forming member and the foot width forming member may be formed of paper.
In a last according to an embodiment of the present disclosure, the foot length forming member and the foot width forming member may configure a part of a packing material for packing an article of footwear.
A last according to an embodiment of the present disclosure may further comprise a common portion invariable in shape and position.
In a last according to an embodiment of the present disclosure, the common portion may configure a bottom surface of the last and have a shape corresponding to that of an upper surface of a footwear sole to which a footwear upper is bonded.
A last according to an embodiment of the present disclosure may further comprise a movable portion invariable in shape and positionally variable.
A last according to an embodiment of the present disclosure may further comprise a cover in the form of a sheet or a plate and externally covering at least a portion of the last.
A method for manufacturing a last according to an embodiment of the present disclosure is a method for manufacturing a last for forming a footwear upper configuring an article of footwear. The method for manufacturing a last comprises the following steps. A first step is a step of preparing a foot length forming member that defines a shape of the last at least in the lengthwise direction of the article of footwear, and a plurality of foot width forming members that define a shape of the last at least in the widthwise direction of the article of footwear. A second step is a step of assembling the foot width forming member to the foot length forming member.
In a method for manufacturing a last according to an embodiment of the present disclosure, the step of preparing the foot length forming member and the foot width forming member may include the steps of: generating a foot model for a user; generating a foot width forming model from the foot model for forming the foot width forming member; and processing a base member based on the foot width forming model to form the foot width forming member.
A method for manufacturing a footwear upper according to an embodiment of the present disclosure comprises the following steps. A first step is a step of covering the last of any one of the above aspects with an unformed upper made of a fiber sheet including a heat-shrinkable yarn. A second step is a step of applying heat to form the unformed upper along the shape of the last to be a formed upper.
Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the scope of the present invention being interpreted by the terms of the appended claims.
Number | Date | Country | Kind |
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JP2020-077796 | Apr 2020 | JP | national |
JP2021-041707 | Mar 2021 | JP | national |
Number | Name | Date | Kind |
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39034 | Clark | Jun 1863 | A |
838874 | Legge | Dec 1906 | A |
1565057 | Chappell | Dec 1925 | A |
4000845 | Zeller | Jan 1977 | A |
6896175 | Duke | May 2005 | B2 |
20110277250 | Langvin et al. | Nov 2011 | A1 |
20160206049 | Kallayil | Jul 2016 | A1 |
20180014609 | Bruce et al. | Jan 2018 | A1 |
20200113291 | Smith | Apr 2020 | A1 |
Number | Date | Country |
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109732913 | May 2019 | CN |
2865358 | Jul 2005 | FR |
Entry |
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The extended European search report issued by the European Patent Office dated Sep. 24, 2021, which corresponds to European Patent Application No. 21168427.9-1005 and is related to U.S. Appl. No. 17/237,996. |
Number | Date | Country | |
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20210330041 A1 | Oct 2021 | US |