US20180116334A1 - Footwear with mechanical foot-insertion assist - Google Patents

Abstract

An article of footwear and methods include an insole, an upper configured to form a space between the upper and the insole configured to admit and secure a foot of a wearer, and a rotatable conveyor element. The rotatable conveyor element is seated in at least one of the insole and the upper. The rotatable conveyor element is configured to rotatably engage a body part of the wearer as the foot enters the space and draw the foot into the space.

Description

PRIORITY
• This application claims the benefit of priority to U.S. Provisional Application No. 62/413,600, “FOOTWEAR WITH FOOT-ENTRY-CONVEYOR ASSIST”, filed Oct. 27, 2016, which is incorporated by reference herein in its entirety.
TECHNICAL FIELD
• The subject matter disclosed herein generally relates to an footwear with a mechanism for foot-insertion assistance.
BACKGROUND
• Articles of footwear that enclose a foot, such as shoes, boots, and close-toed sandals, conventionally utilize a sole and a textile and/or leather “upper” to define a space into which the foot may be inserted and secured. A collar and throat of the upper provides a point of entry to the space. A wearer positions the footwear such that the foot can pass through the collar and throat and applies enough relative force between the foot and the footwear that the foot overcomes the friction with the footwear that the foot passes through the collar and into and substantially into the space.
BRIEF DESCRIPTION OF THE DRAWINGS
• Some embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings.
• FIGS. 1A and 1B are a cutaway depiction of footwear and a block circuit diagram of electronic components of the footwear, in an example embodiment.
• FIGS. 2A and 2B are side and top-down views of the insole conveyor belt with respect to the insole, in an example embodiment.
• FIGS. 3A-3C illustrate the insole conveyor belt being utilized to draw a foot into the space within the footwear, in an example embodiment.
• FIGS. 4A and 4B illustrate side and top cutaway views of footwear including a collar mechanism configured to draw a foot the footwear, in an example embodiment.
• FIGS. 5A and 5B are images of footwear including an upper having an integrated sock section, in an example embodiment.
DETAILED DESCRIPTION
• Example methods and systems are directed to an footwear with a mechanism for foot-insertion assistance. Examples merely typify possible variations. Unless explicitly stated otherwise, components and functions are optional and may be combined or subdivided, and operations may vary in sequence or be combined or subdivided. In the following description, for purposes of explanation, numerous specific details are set forth to provide a thorough understanding of example embodiments. It will be evident to one skilled in the art, however, that the present subject matter may be practiced without these specific details.
• In general, overcoming the friction between the foot and footwear (herein after simply “footwear”) may conventionally involve techniques including gripping the footwear with the hands and one or both of pulling the footwear over the shoe and pushing the foot into the footwear. Additionally, the footwear may be secured against a wall, floor, or other apparatus and the foot pushed into the footwear. Devices, such as shoehorns and the like, have been developed for temporary insertion into the footwear to reduce the friction needed to overcome to insert the foot. However, in such cases, the footwear itself may tend to passively oppose the insertion of the foot.
• Footwear has been developed that includes one or more integrated rotatable conveyor elements to assist the insertion of the foot into the footwear and/or to actively draw the foot into the footwear. In various examples, a the rotatable conveyor elements are one or more of a conveyor belt integrated into the sole and/or the upper functions to draw the foot into the space. The conveyor belt may be unpowered and passively reduce the friction between the footwear and the foot or may be powered to actively draw the foot into the space. In further examples, the rotatable conveyor element may be an integrated collar mechanism in the collar and/or throat of the footwear further configured to engage with the foot, ankle, and/or leg to assist or draw the foot into the footwear and, in certain examples, secure the footwear around and to the ankle and/or leg.
• FIGS. 1A and 1B are a cutaway depiction offootwear100 and a block circuit diagram102 of electronic components of thefootwear100, in an example embodiment. Thefootwear100 includes anoutsole104 designed to come into contact with a surface, such as the ground or a floor, an insole106 configured to seat a human foot, an upper section (“upper”)108 configured to enclose the human foot, and atongue110 configured to facilitate securing thefootwear100 to the human foot vialaces112. A collar114 of the upper108 defines athroat section116 into and through which a foot is inserted to gain access to aspace118 in which the foot is seated. It is to be recognized that this is a simplified depiction ofconventional footwear100 and that thefootwear100 may incorporate any of a variety of components or features. Further, thefootwear100 may not incorporate all of these features or may include these features in other formats (e.g., a sandal may incorporate theoutsole104 and a reconfiguredupper section106 and noinsole106,tongue110, and laces112). It is contemplated that the principles disclosed herein will be applicable and adaptable to any of a range offootwear100.
• Thefootwear100 further includes aninsole conveyor belt120 integrated into theinsole106. Thefootwear100 further optionally includes anupper conveyor belt122 integrated into the upper108. Alternatively, thefootwear100 does not include theinsole conveyor belt120 but does include theupper conveyor belt122. While theinsole conveyor belt120 andupper conveyor belts122 are described as conveyor belts in particular, it is to be understood that any suitable mechanism for longitudinally conveying the foot along theinsole106. As such, mechanisms such as a clamp that runs along a track integrated into theinsole106 or other related mechanisms may also be utilized instead of in addition to theconveyor belt120 or may be applied in addition to or instead of theconveyor belt122.
• In an example, theinsole conveyor belt120 is coupled to amotor124 which is coupled to apower source126, such as a battery, capacitor, supercapacitor, or other suitable energy storage device. Thepower source126 may be replaceable and/or rechargeable. In examples where thepower source126 is rechargeable, thepower source126 may include or may be coupled to a kinetic energy generator, such as a piezoelectric generator or other suitable power generation mechanism. Acontroller128 is coupled to themotor124 andpower source126 and is configured to cause themotor124 to deliver power to one or more components of theinsole conveyor belt120 to cause theinsole conveyor belt120 to turn to draw the foot into thefootwear100. It is noted that themotor124 may include one or more individual motors coupled to thepower source126 andcontroller128 to deliver motive power to discrete components of theinsole conveyor belt120.
• In various examples, thecontroller128 is coupled to anactivation mechanism130, such as a switch or mechanism to detect the presence of the foot or other body party of the user. The switch may be located so that the foot triggers the switch when the foot enters thefootwear100 or the switch may be accessible so that the wearer may intentionally trigger the switch. The switch may be any of a variety of mechanisms, including but not limited to a pressure sensor, a magnet may be positioned in relation to a magnetometer such that the entry of the foot into thefootwear100 causes a sensed magnetic field by the magnetometer to change, a sensor may sense a change in capacitance that may be induced by the presence of the foot, and so forth. Additionally or alternatively, theactivation mechanism130 may be or may include an accelerometer, a gyroscope, or other sensor configured to detect a change in the physical orientation or movement of thefootwear100.
• Upon theactivation mechanism130 being triggered, thecontroller128 may cause themotor124 to drive theinsole conveyor belt120 to draw the foot into thespace118. A further triggering of theactivation mechanism130 may cause the controller to induce the motor to drive in the opposite direction to help move the foot out of thespace118. In various examples, theactivation mechanism130 may utilize the switch to draw the foot into thespace118 and may utilize the sensor to detect a change in orientation or movement of the footwear, e.g., by implementing a predetermined movement with thefootwear100, such as clicking the heels, to push the foot out of thespace118.
• FIGS. 2A and 2B are side and top-down views of theinsole conveyor belt120 with respect to theinsole106, in an example embodiment. Theinsole conveyor belt120 includes abelt200 secured between at least twowheels202,204. In various examples, one or both of thewheels202,204 are coupled to and driven by themotor124. In various examples, thebelt200 may have a relatively sticky or abrasiveexternal surface206 to promote contact with the toes and/or bottom surface the foot or a sock worn by the foot. In various examples, thebelt200 may have a relatively smoothinner surface208 to promote low friction in circumstances where theinner surface208 comes into contact with itself between thewheels202,204 owing to slack in thebelt200 or force imparted by the foot. In examples where theinner surface208 is smooth, one or both of thewheels202,204 may include teeth, nubs, or other mechanisms to promote engagement with theinner surface208 even when theinner surface208 promotes relatively low friction. In various examples, thebelt200 is made from latex, another suitable polymer, or any suitable material.
• In the illustrated example, theinsole conveyor belt120 extends from approximately the middle210 of theheel region212 to anarea214 consistent with the ball of the foot, though different lengths of theinsole conveyor belt120 are contemplated. As such, theinsole conveyor belt210 may tend to maintain contact with at least a portion of the foot that tends to have relatively high pressure on theinsole106 during a normal insertion of the foot into thefootwear100. Thebelt200 has awidth216 approximately one third that of amaximum width218 of theinsole106, though alternative width ratios are contemplated.
• The principles described with respect to theinsole conveyor belt120 apply as well to theupper conveyor belt122. Rather than being configured to engage with the toes or bottom of the foot, though, theupper conveyor belt122 may engage with an upper surface of the foot or sock. As noted herein, thewheels202,204 may in certain examples of theupper conveyor belt122 not be connected to amotor124 and instead may function to provide for reduced friction on the top of the foot rather than providing motive force to actively draw the foot in to thespace118.
• FIGS. 3A-3C illustrate theinsole conveyor belt120 being utilized to draw afoot300 into thespace118 within thefootwear100, in an example embodiment. For simplicity, theupper conveyor belt122 is omitted but it is to be understood that various examples may include theupper conveyor belt122.
• InFIG. 3A thefoot300 is inserted through thethroat section116 of thefootwear100 until thetoes302 are in contact with theinsole conveyor belt120. At some point during the insertion of thefoot300 through thethroat section116 and contact with thebelt200 theactivation mechanism130 is triggered by pressure from or otherwise by the presence of thefoot300 in thefootwear100. Alternatively, the wearer of thefootwear100 manually triggers a switch of theactivation mechanism130.
• InFIG. 3B, thecontroller128 causes themotor124 to deliver power to one or both of thewheels202,204 which turn, causing thebelt200 to impart force on thefoot300 to draw the foot into thespace118. In various examples, thefootwear100 may optionally incorporate additional mechanisms to aid in the insertion and removal of thefoot300. In an example, theinsole106 and/or the upper108 are equipped with a lever or ramp303 configured to deploy behind thewheel204 and sloping upward toward theheel308 of thefootwear100. In such an example, theramp303 may be coupled to themotor124 and other electronic components and deployed at the same time theinsole conveyor belt120 begins to rotate. Alternatively, theramp303 may be spring loaded or otherwise mechanically deployed, e.g., by thefoot300 touching a mechanical switch coupled to a spring mechanism or other deployment mechanism. Theramp303 may provide for relative ease of insertion or removal of the foot by reducing the angles thefoot300 may tend to encounter during insertion and removal, e.g., by not running directly into theinsole106 or heel of thefootwear100.
• In various examples, thecontroller128 provides an acceleration and deceleration profile for theinsole conveyor belt120. While thecontroller128 may control the movement on a binary on/off basis, in certain examples the starting and stopping of turning thewheels202,204 may have a deliberate acceleration and deceleration profile to lessen a likelihood of sudden starts and stops which may provide discomfort to the wearer. Thus, in an example in which themotor124 turns thewheels202,204 for two seconds during insertion and/or removal of thefoot300, themotor124 may accelerate thewheels202,204 for three-quarters of a second, hold a constant speed for one-half of a second, and decelerate for three-quarters of a second, among any of a variety of potential acceleration and deceleration profiles.
• InFIG. 3C, thecontroller128 causes themotor124 to cease to deliver power, causing thebelt200 to stop turning. In various examples, theactivation mechanism130 includes a sensor in or near atoe box304 of thefootwear100 to detect when thetoes302 generally occupy thetoe box304, meaning that thefoot300 is generally seated within thespace118. Alternatively, thecontroller128 may cause themotor124 to cease to delivery power after a predetermined period of time sufficient to draw thefoot300 into thespace118 or the wearer may perform a predetermined action, such as one of those disclosed herein, to cause thecontroller128 to cease operation of themotor124.
• Upon completion of insertion of thefoot100, thecontroller128 may cause themotor124 and/or thewheels202,204 to lock to prevent free movement of thebelt200. In such an example, themotor124 may be configured to actively resist movement of thewheels202,204 if force is exerted on thewheels202,204 by way of thebelt200 during normal wear. Additionally or alternatively, a physical brake may be deployed on thewheels202,204 to passively prevent turning of thewheels202,204 unless deliberately caused by themotor124. Any of a variety of additional brakes or mechanisms for preventing unintentional turning of theinsole conveyor belt120 are contemplated.
• The sequence described herein with respect to drawing thefoot300 into thefootwear100 may be repeated in reverse to push thefoot300 out of thefootwear100. It is noted that aheel306 of thefoot300 may advantageously be slipped form aheel region308 of thefootwear100 prior to engaging themotor124. Additionally or alternatively, a conveyor belt or other mechanism disclosed herein may be positioned in theheel region308 or throat section114 to promote the removal of thefoot300 from thefootwear100.
• FIGS. 4A and 4B illustrate side and top cutaway views, respectively, offootwear400 including acollar mechanism402 configured to draw afoot300 into thefootwear400, in an example embodiment. Thefootwear400 includes some or all of the components of thefootwear100, including, in examples in which thecollar mechanism402 is an active collar mechanism, themotor124, thepower source126, thecontroller128, and the activation mechanism. Examples in which thecollar mechanism402 is passive may omit some or all of themotor124, thepower source126, thecontroller128, and the activation mechanism.
• Thecollar mechanism402 includesmultiple wheels404,406,408,410. Various examples may include more or fewer wheels than the four illustrated. In the illustrated example, thewheels404,406,408,410 are rotatably coupled to the inside oftubing412 of thecollar mechanism402. In various examples, thetubing412 is flexible and is made from a polymer, a medical-grade plastic, or any other suitable material. In various examples, thetubing412 is comprised of a single length of tubing circumferentially joined together, or is comprised of multiple discrete segments each coupled to at least one but not all of thewheels404,406,408,410. In various examples, thetubing412 is or is coated on anexterior surface414 with latex or other material suitable to promote a friction engagement with a foot, leg, sock, or other apparel worn by a wearer of thefootwear400.
• In an alternative example, thetubing412 is omitted and thewheels404,406,408,410 are positioned to come into contact with a foot, leg, sock, or other apparel worn by a wearer of thefootwear400. In such an example, thewheels404,406,408,410 may be coated with latex or other suitable material or my otherwise be configured to promote engagement with the wearer. As such, thewheels404,406,408,410 may be coated in or made from latex, another suitable material, or may be roughened or otherwise configured to promote engagement with the wearer. The principles described with respect to thetubing412 may, as such, also apply to any examples in which thetubing412 is omitted in favor of direct contact with thewheels404,406,408,410.
• As the wearer inserts afoot300 into thethroat section416 thefoot300 and/or associated sock or apparel may come into contact with thetubing412. In examples where thecollar mechanism402 is passive, the force imparted by the wearer on thetubing412 may cause thetubing412 to rotate with thewheels404,406,408,410, providing for comparatively less friction than would be the case if thefoot300 was rubbing against only the upper418. Where thecollar mechanism402 is active, theactivation mechanism130 may output a signal as described herein, based on which the controller causes themotor124 to drive the wheels so as to draw thefoot300 into thespace420. In contrast to theinsole conveyor belt120 offootwear100, thecollar mechanism402 may engage with first thefoot300 and then one or both of the ankle and/or leg of the wearer as thefoot300 is drawn further into thespace420. Similarly, when the wearer is ready to remove thefootwear400 thecontroller124 may reverse the drive on thewheels404,406,408,410, again as disclosed herein with respect to theinsole conveyor belt120.
• FIGS. 5A and 5B are images offootwear500 including an upper502 having anintegrated sock section504, in an example embodiment. Thefootwear500 may be an adaptation of thefootwear400, in that thecollar mechanism402 may be included or otherwise adapted herein. In particular, thesock section504 includes at least a semi-rigidinterior portion506 configured to engage with aposterior side508 of thewheels404,408 (wheels406,410 may be present but are omitted from this image for clarity) relative to ananterior side510 of the wheels which is configured to engage with thefoot300. Anoptional exterior portion508 may be relatively more flexible than theinterior portion506. Alternatively, theexterior portion508 may be semi-rigid in addition to or instead of theinterior portion506.Portions506,508 may be defined as semi-rigid to the extent that they are configured to receive force from thewheels404,408 and transfer the force to thesock section504 generally.
• As thewheels404,408 turn as thefoot300 is inserted into thefootwear500, thewheels404,408 impart a force on theinterior portion506. InFIG. 5A thesock section502 is in a coiled state in which the interior andexterior portions506,508 are relatively low and coiled or bunched. The force from thewheels404,408 causes theportions506,508 to uncoil or unbunch and rise relative to thewheels404,408, as illustrated inFIG. 5B. As such, in an illustrative example, in the coiled state inFIG. 5A thesock section502 may rise approximately to an ankle of a wearer while in the uncoiled state inFIG. 5B thesock section502 may rise over the ankle and a portion of the way up the leg of the wearer.
• Because thewheels404,408 function as part of thecollar mechanism402 generally, it is to be understood that the rising of thesock section502 occurs as the wearer inserts theirfoot300 into thefootwear500. Thus, before the wearer inserts theirfoot300 thesock section502 is coiled and low. As thefoot300 enters thefootwear500 and thewheels404,408 turn, either actively or passively, the force imparted from thewheels404,408 to theinterior portion506 causes thesock section502 to rise and crawl up thefoot300, ankle, and/or leg during the insertion process. Similarly, during the removal process, as thewheels404,408 turn the opposite direction, the force on theinterior portion506 causes thesock portion502 to lower and coil or otherwise bunch. Thus, as thefoot300 withdraws from thefootwear500 thesock portion502 automatically lowers.
• Thefootwear500 may optionally include a zipper or other mechanism that may function to provide an additional opening in the collar and/or throat of thefootwear500 to ease admitting thefoot300 into thefootwear300. The zipper may be manual or may be coupled to themotor124 for automation either separately from or in conjunction with thecollar mechanism402 and the raising and lowering of thesock section502. Thus, in an example, as thesock section502 rises as the wearer puts thefootwear500 on, the zipper may similarly rise from a lowered position to a raised position. As thesock section502 lowers as the user goes to remove thefootwear500, the zipper may similarly lower. It is emphasized that while the zipper is discussed for purposes of illustration, any suitable mechanism may be utilized accordingly. Moreover, multiple zippers and/or other mechanisms may be incorporated to provide a desired look or wearing profile.
• The principles disclosed herein with respect toindividual footwear100,400,500 may be combined in individual footwear. Thus, footwear may incorporate both theinsole conveyor belt120 and thecollar mechanism402. Thefootwear400,500 may incorporate theramp303 while thefootwear100,400 may incorporate the zipper offootwear500. Theramp303 may be mechanically deployed while the zipper may be electromechanically operated by themotor124. It is specifically contemplated that any particular component of each of thefootwear100,400,500 may be incorporated in various combinations as desired.
• Throughout this specification, plural instances may implement components, operations, or structures described as a single instance. Although individual operations of one or more methods are illustrated and described as separate operations, one or more of the individual operations may be performed concurrently, and nothing requires that the operations be performed in the order illustrated. Structures and functionality presented as separate components in example configurations may be implemented as a combined structure or component. Similarly, structures and functionality presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter herein.
• The performance of certain of the operations may be distributed among the one or more processors, not only residing within a single machine, but deployed across a number of machines. In some example embodiments, the one or more processors or processor-implemented modules may be located in a single geographic location (e.g., within a home environment, an office environment, or a server farm). In other example embodiments, the one or more processors or processor-implemented modules may be distributed across a number of geographic locations.
• Some portions of this specification are presented in terms of algorithms or symbolic representations of operations on data stored as bits or binary digital signals within a machine memory (e.g., a computer memory). These algorithms or symbolic representations are examples of techniques used by those of ordinary skill in the data processing arts to convey the substance of their work to others skilled in the art. As used herein, an “algorithm” is a self-consistent sequence of operations or similar processing leading to a desired result. In this context, algorithms and operations involve physical manipulation of physical quantities. Typically, but not necessarily, such quantities may take the form of electrical, magnetic, or optical signals capable of being stored, accessed, transferred, combined, compared, or otherwise manipulated by a machine. It is convenient at times, principally for reasons of common usage, to refer to such signals using words such as “data,” “content,” “bits,” “values,” “elements,” “symbols,” “characters,” “terms,” “numbers,” “numerals,” or the like. These words, however, are merely convenient labels and are to be associated with appropriate physical quantities.
• Unless specifically stated otherwise, discussions herein using words such as “processing,” “computing,” “calculating,” “determining,” “presenting,” “displaying,” or the like may refer to actions or processes of a machine (e.g., a computer) that manipulates or transforms data represented as physical (e.g., electronic, magnetic, or optical) quantities within one or more memories (e.g., volatile memory, non-volatile memory, or any suitable combination thereof), registers, or other machine components that receive, store, transmit, or display information. Furthermore, unless specifically stated otherwise, the terms “a” or “an” are herein used, as is common in patent documents, to include one or more than one instance. Finally, as used herein, the conjunction “or” refers to a non-exclusive “or,” unless specifically stated otherwise.

Claims (24)

1. An article of footwear, comprising:

an insole;

an upper configured to form a space between the upper and the insole configured to admit and secure a foot of a wearer; and

a rotatable conveyor element, seated in at least one of the insole and the upper, configured to rotatably engage a body part of the wearer as the foot enters the space and draw the foot into the space.

2. The article of footwear ofclaim 1, further comprising:

a motor, coupled to the rotatable conveyor element, configured to deliver motive power to the rotatable element;

an activation mechanism, configured to output a signal to activate the motor; and

a controller, coupled to the motor and to the activation mechanism, configured to cause the motor to deliver motive power to the rotatable element based, at least in part, on the signal form the activation mechanism.

3. The article of footwear ofclaim 2, wherein the activation mechanism is a foot sensor.

4. The article of footwear ofclaim 2, wherein the activation mechanism is a switch.

5. The article of footwear ofclaim 1, wherein the rotatable conveyor element is a conveyor belt.

6. The article of footwear ofclaim 5, wherein the conveyor belt is seated in and extends along a portion of the insole.

7. The article of footwear ofclaim 5, wherein the conveyor belt is seated in an extends a long a portion of the upper.

8. The article of footwear ofclaim 1, wherein the upper forms a collar to admit the foot of the wearer and wherein the rotatable conveyor element is a collar mechanism positioned in the collar.

9. The article of footwear ofclaim 8, wherein the collar mechanism comprises a wheel.

10. The article of footwear ofclaim 9, wherein the collar mechanism further comprises a flexible tube extending around at least a portion of the collar, wherein the wheel is secured within the tube.

11. The article of footwear ofclaim 10, wherein the collar mechanism further comprises a coating around the flexible tube comprised of at least one of: latex and a polymer.

12. The article of footwear ofclaim 9, wherein the upper forms a sock section and wherein the collar mechanism is coupled to the sock section and configured to cause the sock section to extend and retract as the wheel turns.

13. A method of making an article of footwear, comprising:

seating a rotatable conveyor element in at least one of an insole and an upper, the rotatable conveyor element configured to rotatably engage a body part of the wearer as the foot enters a space and draw the foot into the space; and

securing the insole with respect to the upper, the insole and upper form the space between the upper and the insole configured to admit and secure a foot of a wearer.

14. The method ofclaim 13, further comprising:

coupling a motor to the rotatable conveyor element, the motor configured to deliver motive power to the rotatable element;

coupling a controller to the motor, the motor configured to cause the motor to deliver motive power to the rotatable element; and

coupling an activation mechanism to the controller, the activation mechanism configured to output a signal to activate the motor.

15. The method ofclaim 14, wherein the activation mechanism is a foot sensor.

16. The method ofclaim 14, wherein the activation mechanism is a switch.

17. The method ofclaim 13, wherein the rotatable conveyor element is a conveyor belt.

18. The method ofclaim 17, wherein seating the rotatable conveyor element comprises seating the conveyor belt in and extending along a portion of the insole.

19. The method ofclaim 17, wherein seating the rotatable conveyor element comprises seating the conveyor belt in an extending a long a portion of the upper.

20. The method ofclaim 13, wherein the upper forms a collar to admit the foot of the wearer and the rotatable conveyor element is a collar mechanism, and wherein seating the rotatable conveyor element comprises securing the collar mechanism in the collar.

21. The method ofclaim 20, wherein the collar mechanism comprises a wheel.

22. The method ofclaim 21, wherein the collar mechanism further comprises a flexible tube extending around at least a portion of the collar, wherein the wheel is secured within the tube.

23. The method ofclaim 22, wherein the collar mechanism further comprises a coating around the flexible tube comprised of at least one of: latex and a polymer.

24. The method ofclaim 21 wherein the upper forms a sock section and wherein the collar mechanism is coupled to the sock section and configured to cause the sock section to extend and retract as the wheel turns.

Images