Collapsible wheels and methods of making collapsible wheels

Abstract

To provide collapsible wheels and methods of making collapsible wheels.SOLUTION: There is provided a collapsible wheel comprising a hub portion, a plurality of spokes, and a plurality of rim portions. Therein: each spoke of the plurality of spokes engages at least one rim portion of the plurality of rim portions; the plurality of rim portions define a circle in an expanded configuration; the plurality of rim portions define a rotational plane; the rim portions comprise a thickness measured orthogonal to the rotational plane; a thickness of the two end sections of each rim portion of the plurality of rim portions is less than a thickness of a center section; and the collapsible wheel can be configured in the expanded configuration or a collapsed configuration.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] This application is a continuation-in-part of U.S. Patent Application No. 16 / 934,995, filed on July 21, 2020, and U.S. Provisional Application No. 62 / 951,509, filed on December 20, 2019, the entire contents of which are incorporated herein by reference.

[0002] This application generally relates to wheels, and more particularly to foldable wheels and methods of making foldable wheels.

Background Art

[0003] Some exercise equipment may require a wheeled vehicle for transportation. For example, a kayak may be transported on a wheeled kayak cart on a river or lake. Before floating the kayak on water, the kayak cart may be removed from the kayak and stored on the kayak. The kayak cart may have a foldable frame to reduce the size of the cart when not in use. In another example, a golfer may carry their golf bag slung over their shoulder on a golf push cart or an electric golf cart. A golf push cart typically has a frame with two wheels attached to move the cart. The frame may also include a handle for a person to hold to balance the cart and pull or push, and a platform or base for placing the person's golf bag. The frame may be foldable to reduce the size of the push cart when not in use for storage and / or transportation.

Brief Description of the Drawings

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[0067] Referring to FIGS. 1 and 2, a wheel 100 according to an example of an apparatus, method, and article of manufacture described herein is shown. The wheel 100 includes a hub assembly 102 and a tire 104, and at least a portion of the tire 104 is mounted around the hub assembly 102 for contacting the ground. The wheel 100 also includes an axle 106 on which the hub assembly 102 is rotatably mounted. One or more wheels 100 may be used in a cart or vehicle for transporting any object.

[0068] FIG. 1 shows the wheel 100 in the deployed position. To reduce the size of the wheel 100 for transportation and / or storage, a person may fold the wheel 100 into the folded position shown in FIG. 2. For example, the trunk of a car may not have enough space to accommodate a push cart for golf clubs when the wheels 100 of the push cart are in the deployed position. By placing the wheel 100 in the folded position, the push cart and the wheel 100 can fit inside the trunk of the car for transportation. Thus, by folding the wheel from the deployed position to the folded position, the wheel and / or any object to which the wheel is attached can occupy a smaller space. Further, as discussed in detail below, each wheel 100 may be removable from the push cart to further reduce the space that can be occupied by the push cart and the wheel 100.

[0069] Also referring to FIGS. 3 - 6, the hub assembly 102 is shown in its deployed and folded positions, respectively. The hub assembly 102 includes a plurality of stacked wheel portions 110. Each wheel portion 110 includes a hub portion 112 having a central hole 114. The wheel portions 110 may be concentrically stacked such that the central holes 114 are axially aligned to form an elongated hole for receiving the axle 106. Each wheel portion 110 may include at least one spoke 116 and a rim 118. In the examples of FIGS. 1 - 5, each wheel portion 110 has a first pair of spokes 116 that project radially from the hub portion 112 for connecting to the first rim 118, and further has a second pair of spokes 116 that project radially from the hub portion 112 on the side opposite the first pair of spokes 116 for connecting to the second rim 118. Each rim 118 receives and supports a portion of the tire 104. Each wheel portion 110 may include any number of spokes 116 that extend from the hub portion 112 to one or more rims 118. For example, each rim 118 may be connected to a single spoke 116 or a plurality of spokes 116. The spokes 116 may be of any shape. For example, each spoke 116 may be straight, bent at one or more locations along the length of the spoke, and / or have a curved portion. In the examples of FIGS. 1 - 5, the spokes 116 may be curved so as to function as springs when the wheel 100 is in use. Thus, when a force is applied to the rim 118 during operation of the wheel 100, the curved shape of each spoke 116 facilitates elastic bending of the spoke 116 such that the spoke 116 provides a shock - absorbing function.

[0070] Each wheel part 110 may be rotatable freely about the axle 106 so that the wheel part 110 can be deployed from the folded position shown in FIG. 4 to the deployed position shown in FIG. 3. The number of wheel parts 110, the thickness of each wheel part 110, and / or the radial span of each wheel part 110 may be determined such that, in the deployed position of the wheel 100, the wheel is a perfect circle, i.e., approximately 360 degrees is defined by the wheel 100, and the rim 118 provides sufficient support to the tire 104 for proper operation of the wheel 100. Providing sufficient support to the tire 104 at all times during operation of the wheel 100 may be defined by the number of contact points between the wheel 100 and the ground. Each rim 118 may be defined as having one contact point, which is referred to herein as a contact point, but the contact point may represent the area of the rim 118 that contacts the ground. By increasing the number of contact points between the wheel 100 and the ground, the stability of the wheel 100 can be increased, and thus the stability of the vehicle to which the wheel 100 is attached, i.e., the handcart, can be increased.

[0071] The radial span of each wheel part 110 may determine the radial position of each wheel part 110 relative to adjacent wheel parts 110 in the deployed position of the wheel 100, and the number of wheel parts 110 that may be required. As shown in FIG. 5 and as used herein, the radial span 119 may generally define the length of the rim 118 that contacts the ground during operation of the wheel 100. For example, if each rim 118 of a pair of rims 118 of the wheel part 110 defines a radial span of about 90 degrees, only two wheel parts 110 may be required such that the rims 118 generally define a perfect circle or about 360 degrees with no overlap or gap between two adjacent rims 118, or each rim 118 may generally define a 90-degree radial span on the perfect circle that defines the wheel 100. In other words, each wheel part 110 may generally define a 180-degree radial span on the perfect circle that defines the wheel. In another example, if each rim 118 of a pair of rims 118 of the wheel part 110 has a radial span 119 of about 45 degrees, four wheel parts 110, i.e., eight rims 118, may be required such that the rims 118 generally define a perfect circle or about 360 degrees with no overlap or gap between two adjacent rims 118. Thus, the general configuration of the wheel 100 may be defined by the following exemplary equation.

Number

[0072] In the above equation, W represents the number of wheel parts, N represents the number of opposing rims 118 on each wheel (for example, N is 2 in the examples of FIGS. 2-5), C represents the number of ground contact points, and R represents the radial interval (in degrees) of each wheel part relative to adjacent wheel parts.

[0073] As described above, the stability of the wheel 100 may increase by increasing the number of contact points between the wheel 100 and the ground. Each rim 118 may contact the ground at one contact point. By providing a plurality of contact points, i.e., a plurality of rims 118, that contact the ground at all times, the stability of the wheel 100 may increase. In other words, by increasing the number of contact points with the ground at all times during the operation of the wheel 100, the width of the wheel 100 increases, thereby increasing the number of wheel portions 110 that can be used to form the wheel 100.

[0074] Referring to FIG. 5, an example of the wheel 100 is shown where each wheel portion has a rim 118 having a radial span 119 of approximately 45 degrees. Thus, adjacent wheel portions 110 may be radially spaced apart by approximately 45 degrees in the deployed position of the wheel 100, as shown in FIG. 5. In the example of FIG. 5, four wheel portions 110, i.e., eight rims 118, should be required to define a perfect circle or approximately 360 degrees. Thus, if the wheel 100 is constructed of four wheel portions 110, only one rim 118, i.e., one contact point, contacts the ground at all times. To increase the stability of the wheel 100, sixteen wheel portions 110 may be provided as shown in the example of FIG. 4 such that four contact points on the wheel 100 contact the ground at all times during the operation of the wheel 100, i.e., four rims 118 define the width of the wheel 100. Any number of wheel portions 110 may be provided to increase or decrease the contact points. For example, twenty wheel portions 110 should provide five contact points to the ground at all times for the wheel 100. In another example, twelve wheel portions 110 should provide three contact points to the ground. According to the above, at least eight rims 118 may be required such that one contact point contacts the ground at all times during the operation of the wheel 100 as each rim 118 spreads at approximately 45 degrees. A plurality of four wheel portions 110 may be provided to increase the number of contact points along the width of the wheel when each rim 118 has a radial span 119 of approximately 45 degrees. In the example of FIG. 4, the sixteen wheel portions 110 for the wheel 100 provide four contact points at all times during the operation of the wheel as shown in FIG. 6.

[0075] By increasing the number of wheel portions 110, the stability of the wheel 100 and / or the weight that the wheel 100 can support may increase. However, by increasing the number of wheel portions 110, the size and / or weight of the wheel 100 in the folded position may also increase. Thus, the size of each wheel portion 110 and the other characteristics of each wheel portion 110 as described herein may be determined depending on the size and load of the cart to which one or more wheels 100 can be attached.

[0076] FIG. 6 shows the deployed positions of two wheel portions 110. The rim 118 of each wheel portion 110 includes a radially projecting 120. Referring to FIGS. 7-11, the tire 104 may include an inner surface 130 and an outer surface 132. The outer surface 132 may be smooth or may have a tread. The inner surface 130 may have any configuration that provides for attachment of the tire 104 on the rim 118. In the examples of FIGS. 8 and 9, the inner surface 130 includes a plurality of generally parallel ribs 134 that define a plurality of generally parallel grooves 136 between the ribs 134. The ribs 134 and grooves 136 may extend radially into a portion of the inner surface 130. In the examples of FIGS. 8 and 9, the ribs 134 and grooves 136 extend across the entire 360 degrees of the inner surface 130 of the tire 104.

[0077] Referring to FIGS. 10 and 11, the distance between adjacent grooves 136 generally corresponds to the distance between the protrusions 120 of adjacent wheel portions 110. Additionally, the cross-sectional shape of each groove 136 may generally correspond to the cross-sectional shape of the protrusion 120. Thus, when the tire 104 is mounted on the wheel portion 110, the protrusion 120 may engage the groove 136 and generally fit within the groove 136. The protrusion 120 and the groove 136 may have any cross-sectional shape. In the example of FIG. 11, the protrusion 120 is shown as having a generally triangular cross-sectional shape, and the groove 136 is also shown as having a generally corresponding triangular cross-sectional shape. Further, the size of the groove 136 may generally correspond to the size of the protrusion 120. For a tire 104 constructed of an elastic material such as rubber, the groove 136 may alternatively be formed smaller than the protrusion 120 such that the groove 136 elastically expands to provide an engagement that generally mates with the protrusion 120 when receiving the protrusion 120. The tire may be attached to one or more rims 118 such that the tire maintains a configuration mounted on the wheel 100 at both the folded and deployed positions of the wheel 100.

[0078] As described above, each wheel portion 110 may be positioned at a particular angle relative to adjacent wheel portions 110 during operation of the wheel 100 in order to provide a sufficient number of contact points and generally uniformly distribute the positions of the contact points across the wheel 100. For example, the wheel portions 110 of FIG. 5 are positioned at approximately 45 degrees relative to each other in the deployed position in order to provide four uniformly distributed contact points at any given time during operation of the wheel 100. The angle between wheel portions 110 in the deployed position that provides a sufficient number of contact points and generally uniformly distributes the positions of the contact points across the wheel is sometimes referred to herein as the deployment angle. The deployment angle is shown in Equation (1) as the variable R. Thus, the deployment angle for the example of FIG. 5 is approximately 45 degrees.

[0079] As described in detail above and as explained with respect to Equation (1), the deployment angle may vary depending on the configuration and / or characteristics of the wheel portion 110. In order to limit the deployment of the wheel portions 110 relative to each other and / or to provide the positioning of the wheel portions 110 in terms of the deployment angle relative to each other, the wheel 100 may include a deployment angle limiting mechanism by which the rotation of each wheel portion 110 relative to the adjacent wheel portion 110 is limited to the deployment angle. According to an example shown in FIG. 12, the angle limiting mechanism may include a radial slot 140 on the hub portion 112 of each wheel portion 110 and a pin 144 that may be disposed on the hub portion 112 on the opposite side of the slot 142 with respect to the central hole 114. The arc length of each radial slot 140 may generally be equal to or less than the deployment angle. In the example of FIG. 12, the arc length of the radial slot 140 is about 45 degrees, which is the same as the deployment angle. When the wheel portions 110 are assembled as will be described in detail below, i.e., stacked on top of each other, the pin 144 of each wheel portion 110 is placed inside the slot 140 of the adjacent wheel portion 110. Thus, when the adjacent wheel portions are rotated relative to each other, the pin 144 moves within the slot 140. However, the radial movement of the pin 144, which defines the radial movement of the wheel portion 110 having the pin 144, is limited by the arc length of the slot 140.

[0080] Each slot 140 includes a first end 150 and a second end 152. In the folded position of the wheel 100, the pin 144 of each wheel part 110 is disposed near the first end 150 of the slot 140 of an adjacent wheel part 110. As the wheel 100 is deployed, the pin 144 moves within the slot 140 from the first end 150 until the pin 144 contacts the second end 152 of the slot 140. Thus, the slot 140 limits the rotation of two adjacent wheel parts 110 relative to each other to the deployment angle or the radial arc length of the slot 140. The positions of each slot 140 and the pin 144 may be determined such that the wheel 100 can be deployed and folded as disclosed. In the example of FIG. 12, the first end 150 of the slot 140 is generally disposed along the central longitudinal axis 154 of the hub part 112. Thus, the second end 152 of the slot 140 is disposed at approximately 45 degrees from the first end 150. Also, the pin 144 is disposed on the central longitudinal axis 154, but on the opposite side of the first end 150 of the slot 140 with respect to the central hole 114. As will be described in detail below, the arrangement of the pin 144 and the slot 140 provides that each wheel part 110 rotates by the deployment angle relative to an adjacent wheel part as shown in FIG. 12.

[0081] After the wheel 100 is deployed, it is defined by each wheel part 110 having a deployment angle relative to an adjacent wheel part 110, and the wheel 100 may be maintained in the deployed position by any type of latch mechanism, locking mechanism, and / or similar mechanism that prevents the wheel parts 110 from rotating relative to each other. For example, each wheel part 110 may include an opening (not shown) positioned on the hub part 112 such that when the wheel part 110 is in the deployed position of the wheel 100, all the openings of the wheel part 110 are generally aligned to receive a rod (not shown). Thus, the rod prevents the wheel parts 110 from rotating relative to each other. In another example, a U-shaped bracket (not shown) having a width generally similar to the overall width of the hub part 112 may be placed on the hub part 112 to prevent the hub parts 112 from rotating relative to each other.

[0082] Referring to FIGS. 13 and 14, the wheel portion 110 may be rotatably mounted on the axle 106. The axle 106 may be defined by a cylindrical shaft 160 having a first end 162 and a second end 164. In the example of FIGS. 13 and 14, the axle 106 may further include a mounting bracket 166 having a first bracket portion 168 and a second bracket portion 170. The mounting bracket 166 may facilitate the mounting or attachment of the wheel 100 to a cart such as a golf push cart. The wheel portion 110 may be mounted on the shaft 160 by inserting the shaft 160 from the first end 162 into the central hole 114 of each wheel portion 110. The axle 106 may include a mechanism by which the first wheel portion 110 mounted on the shaft 160 is kept stationary, so that the wheel 100 can be deployed from the folded position. In one example as shown in FIG. 13, the first bracket portion 160 includes a pin hole 170 for receiving the pin 144 of the first mounted wheel portion 110. The engagement of the pin 144 with the pin hole 170 of the first mounted wheel portion 110 secures the first mounted wheel portion 110 fixed to the first bracket portion 160 so that the wheel 100 can be deployed from the folded position to the deployed position. After the wheel 100 is deployed, the pin 144 may be removed from the pin hole 170 so that the wheel 100 can rotate about the shaft 160.

[0083] The axle 106 may further include a wheel retaining mechanism by which the wheel 100 is maintained on the shaft 160 during operation of the wheel 100. The wheel retaining mechanism may include any configuration that prevents the wheel 100 from sliding off or being removed from the axle 106 during operation of the wheel 100. For example, the first end 162 of the shaft 160 may be threaded to receive a correspondingly threaded nut (an example is shown in FIG. 22). The threaded nut increases the diameter of the shaft 160 at the first end 162 to a diameter larger than the central hole 114 of the hub portion 112. Thus, the wheel portion 110 is stopped by the nut when it reaches the first end 162 of the shaft 160.

[0084] In the example of FIG. 13, the shaft 160 includes an annular recess 172 at or near the first end 162 of the shaft 160. As shown in FIG. 14, after the wheel portion 110 is mounted on the shaft 160, the spring clip 174 may be mounted on and pressed onto the shaft 160 such that the spring clip 174 is snapped into the annular recess 172 and remains within the annular recess 172. The spring clip 174 increases the diameter of the shaft 160 at the first end 162 to a diameter larger than the diameter of the central hole 114 of the hub portion 112. Thus, the wheel portion 110 is stopped by the spring clip 174 when it reaches the first end 162 of the shaft 160. The axle 106 may also include a washer 176 or the like mounted between the spring clip 174 and the last-mounted wheel portion 110. To provide for easy installation of the spring clip 174 into the annular recess 174, the first end 162 of the shaft may be tapered as shown in FIGS. 13 and 14 such that the spring clip 172 gradually unfolds onto the shaft 160 when pressed onto the first end 162. Thus, the spring clip 174 remains engaged with the annular recess 172 until the spring clip 174 is unfolded, regardless of the presence or absence of a tool for a person to remove the spring clip 174 from the shaft 160, and the wheel portion can then be removed from the shaft 160 thereby. At the second end 164 of the shaft 160, an annular shoulder 178 may be provided such that the first mounted wheel portion 110 is spaced from the first bracket portion 168.

[0085] FIG. 2 shows the wheel 100 in a folded position having a tire 104 mounted thereon. The tire 104 may be constructed from an elastic material such as rubber. Further, the inner diameter of the tire 104 may be smaller than the outer diameter of the circle defined by the wheel 100 in the deployed position. Thus, the tire can be easily mounted on the wheel 100 in the folded position. However, when the wheel 100 is deployed, the tire 104 may elastically deploy. The elastic deployment of the tire 104 may generate a restoring force within the tire 104 that thereby maintains the tire 104 on the wheel 100 as the tire 104 is pressed onto the rim 118 (e.g., the protrusion 120 is pressed into the groove 136) during operation of the wheel 100.

[0086] To deploy the wheel 100 from the folded position to the deployed position, each wheel portion 110 may be rotated by hand. In one example shown in FIGS. 15 and 16, the wheel 100 includes a hub cap 200 by which the wheel portions 110 can be rotated relative to each other to deploy the wheel 100. The hub cap 200 may include two opposing handles 202 and 204 that can be held by a person to rotate the hub cap 200. The hub cap 200 may include pins (not shown) on its inner surface, and the inner surface may engage inside the slot 140 of the last attached wheel portion 110. The hub cap 200 may be rotatably mounted on the shaft 106. Thus, when the hub cap 200 is rotated by a person about the shaft 106, the pins on the inner surface of the hub cap 200 move within the slot 140 of the first wheel portion 110 until the pins engage the second end 152 of the slot 140. After the first wheel portion 110 has been rotated through the deployment angle, the pin 144 of the first wheel portion 110 engages the second end 152 within the slot 140 of the second wheel portion 110 as described above. Thus, further rotation of the hub cap 200 causes the second wheel portion 110 to rotate through the deployment angle relative to the third wheel portion 110. By continuing the rotation of the hub cap 200, the remaining wheel portions 110 rotate until the wheel 100 is fully deployed. The hub cap 200 may be mounted on the shaft 160 between the last attached wheel portion 110 and the spring clip 174. When holding the handles 202 and 204, a person may also hold the second bracket portion 166 to provide the leverage effect when deploying the wheel 100.

[0087] Figures 17 and 18 show a wheel 400 according to another example. The wheel 400 is similar to the wheel 100 in certain aspects. Thus, similar parts of the wheels 100 and 400 are denoted by the same reference numerals. The wheel 400 includes a plurality of wheel portions 110 mounted on an axle 406 (shown in FIG. 17). The axle 406 includes a first end 462 (shown in FIG. 17) and a second end (not shown). The axle 406 receives the wheel portion 110 by being inserted into the central hole 114 of the wheel portion 110. The second end of the axle 406 includes a base 470 having a diameter larger than the diameter of the central hole 114 of the wheel portion 110. Thus, when the wheel portion 110 is mounted on the axle 406, the wheel portion 110 is fixed at the second end of the axle by the base 470. To prevent the wheel portion 110 from being removed from the axle 406 during operation of the wheel 400, the second end 462 of the axle 406 may be threaded to receive a correspondingly threaded nut 480. Thus, tightening the nut 480 on the threaded first end 462 of the axle 406 prevents the wheel portion 110 from being removed from the axle 406 during operation of the wheel 400. Alternatively, the axle 400 may include a wheel retaining mechanism similar to the wheel retaining mechanism of the wheel 100, as detailed above. The wheel 400 includes a hub cap 200, which may be used to deploy the wheel 400 from a folded position to a deployed position, as detailed above with respect to the wheel 100.

[0088] Referring to FIG. 18, the first mounted wheel portion 110 may include two opposing handles 502 and 504 on the central hub portion 112 that are positioned similarly to the handles 202 and 204 of the hub cap 200. Thus, a person can hold the handles 202 and 204 with one hand, rotate the handles 202 and 204 in one direction, hold the handles 502 and 504 with the other hand, and rotate the handles 502 and 504 in the opposite direction to rotate the wheel portions relative to each other to deploy the wheel 400 to the deployed position. The wheel 400 can be deployed from the folded position. The handles 502 and 504 may be part of a hub cap (not shown) that is mounted on the axle 406 before the first mounted wheel portion 110 is mounted on the axle 406. Alternatively, as shown in FIGS. 17 and 18, the handles 502 and 504 may be an integral part of the first mounted wheel portion 110.

[0089] Referring to FIGS. 19 and 20, a wheel 600 according to another embodiment is shown. The wheel 600 is similar to the wheels 100 and 400 in some aspects. Thus, like parts of the wheels 100, 400, and 600 are designated with the same reference numerals. The wheel 600 includes a plurality of wheel portions 610. Each wheel portion 610 includes a hub portion 612 having a central hole (not shown). Each wheel portion 610 includes a pair of spaced generally straight spokes 616 on each side of the outer peripheral portion of the hub portion 612 that project radially outward and connect to a generally curved rim 618. The distance between each pair of spokes 616 may increase from the hub portion 612 to the rim 618. Thus, each pair of spokes 616 and the corresponding rim 618 generally define a trapezoidal shape. The wheel 600 includes an axle 606 that is mounted through the central hole of the wheel portion 610. The axle 606 and the mechanism and method by which the axle 606 is operably connected to the wheel and the cart are similar to the axles 106 and 406. Thus, a detailed description of the axle 606 is not provided.

[0090] Referring to FIGS. 21 - 25, a wheel 800 according to another example is shown. The wheel 800 includes a hub assembly 802 and a tire (not shown) mounted on the hub assembly 802 as described below. The wheel 800 also includes an axle 806 on which the hub assembly 802 and the tire are rotatably mounted. The hub assembly 802 includes a plurality of wheel portions 810 coaxially mounted on the axle 806. Each wheel portion 810 includes a hub portion 812 having a central hole 814 for receiving a portion of the axle 806.

[0091] The tire may be mounted on a plurality of rims 818 positioned along the outer periphery of a circle 817 that defines the central plane of the wheel 800. Each rim 818 is oriented generally perpendicular to the circle 817 (shown in FIG. 24) and is convex with respect to the hub portion 812. Thus each rim 818 is concave with respect to the tire so as to receive the curved portion of the tire (not shown). Each rim 818 is attached to two spaced - apart hub portions 812 by two spokes 816 respectively. The two hub portions 812 to which the rim 818 is attached by the spokes 816 are spaced apart such that the spokes 816 form a V - shaped support for each rim 818. For example, as shown in FIG. 22, the spokes 816 that support the rim 818 connected to the hub portion 812 are spaced apart by only five hub portions 812. Thus each hub portion 812 has one spoke 816 on one of its sides that partially supports the first corresponding rim 818 and another spoke 816 on the opposite side of it that partially supports the second corresponding rim 818.

[0092] Figures 23 to 25 show the deployed position of the wheel 800. The spokes 816 are positioned on the hub portion 812 such that when the wheel 800 is in the deployed position, the spokes 816 are evenly distributed around the wheel, i.e., radially spaced at the same deployment angle on the circle 817. In the example of Figures 23 to 25, the spokes 816 are shown to be approximately 30 degrees apart at the deployed position of the wheel 800. Figures 21 and 22 show the folded position of the wheel 800. To fold the wheel 800, the hub portions 812 may be rotated relative to each other until the rims 818 contact each other and further rotation of the hub portions 812 is prevented. To deploy the wheel 800, the hub portions 812 may be rotated in opposite directions relative to each other such that the wheel 800 reaches the deployed position shown in Figure 23. Since each spoke 816 is disposed on a different hub portion 812, the wheel 800 may require a rotation of less than 180 degrees to deploy from the folded position to the deployed position. Thus, to deploy the wheel 800 from the folded position as shown in Figure 21, the spoke 820 is rotated clockwise until the spoke 820 is positioned close to the spoke 822 and further rotation is prevented by a deployment limiting mechanism as described below. At the same time, the spoke 824 is rotated clockwise until the spoke 824 is positioned close to the spoke 826 and further rotation is prevented by the deployment limiting mechanism. Thus, the maximum rotation of the hub portion 812 may be less than 180 degrees to deploy the wheel from the folded position to the deployed position.

[0093] When the wheel 800 reaches the deployed position shown in Figure 23, the wheel 800 may include a deployment limiting mechanism as described above to prevent further rotation of the hub portions 812 relative to each other. Thus, each wheel portion 810 may include a radial slot (not shown) on the hub portion 812 and a pin (not shown) that may be disposed on the hub portion 812 on the side opposite the slot relative to the central hole 814. The arc length of each radial slot 140 may generally be less than or equal to the deployment angle. In the example of Figure 24, the arc length of the radial slot is approximately 30 degrees, which is the same as the deployment angle.

[0094] A tire (not shown) may be mounted on the wheel 800 before and after the wheel is deployed. The tire may be constructed from solid-piece rubber or other types of plastic materials having sufficient elasticity to allow the tire to be mounted on the wheel 800. Alternatively, the tire may be in the form of an inflatable tube that may be mounted on the rim 818. Thus, the tire may be inflated by a person before operating the wheel 810. As yet another alternative, the tire may be attached to one or more rims 818 such that the tire is maintained in a configuration mounted on the wheel 800 at both the folded and deployed positions of the wheel 800.

[0095] Figures 26 - 33 show several exemplary wheels and / or wheel assemblies according to the present disclosure. As shown in Figure 26, the wheel assembly 1010 may include at least one spoke 1016 on each side surface of the hub portion 1012. The wheel assembly 1010 also includes at least one rim 1018 attached to each spoke 1016. Each spoke 1016 and the corresponding rim 1018 generally define a T-shaped spoke and rim assembly. The wheel assembly 1110 as shown in Figure 27 may include at least one spoke 1116 on each side surface of the hub portion 1112. The wheel assembly 1110 also includes at least one rim 1118 attached to each spoke 1116. Each spoke 1116 and the corresponding rim 1118 generally define an L-shaped spoke and rim assembly. According to the exemplary wheel assemblies 1010 and 1110, at least one rim and at least one spoke may be attached to each other in any configuration. For example, the end of the spoke may be attached to the center of the length of the rim as shown by the wheel assembly 1010 to generally provide a T-shaped spoke and rim assembly. However, in the exemplary wheel assembly 1110, the end of the spoke is attached to one end of the rim. Thus, the spoke and the rim may be attached to each other in any configuration and with any type of offset relative to each other.

[0096] Figures 28 and 29 show a wheel 1200 according to another example. The wheel 1200 includes a plurality of wheel portions 1210, where in this case each wheel portion 1210 may have a different configuration compared to one or more other wheel portions 1210. For example, each wheel portion 1210 may have spokes 1216 of different shapes. The spokes 1216 may be straight, curved, L-shaped, Z-shaped, and / or may have any other shape that may differ from the spokes 1216 of one or more other wheel portions 1210. Depending on the shape of each spoke 1216, each spoke may have a different thickness, may be constructed from a different material, and / or may have certain characteristics that may differ from or be similar to one or more other spokes 1216 of one or more other wheel portions 1210. The tire 1204 may be mounted on the wheel 1200 in both the folded and deployed positions of the wheel 1200.

[0097] Figures 30 and 31 show a wheel 1300 according to another example. The wheel 1300 includes a plurality of spokes 1316. Each spoke may be flexible so as to deform from a deployed position corresponding to the deployed position of the wheel 1300 to a deformed position corresponding to the folded position of the wheel 1300. FIG. 30 shows an example of the wheel 1300 in the process of being deployed between the folded position and the deployed position shown in FIG. 31. In the deployed position of the spokes 1316 as shown in FIG. 31, the spokes 1316 have sufficient overall rigidity to support the loads on the tire 1304 and the hub assembly 1302 to provide the operation of the wheel 1300 as disclosed. However, the spokes 1316 are flexible so that the wheel 1300 can be folded by deforming the spokes 1316 to fold the wheel 1300. As shown in the example of FIG. 30, the spokes 1316 are deformed by being bent and may be stacked on top of each other around the hub 1312. Also, the spokes 1316 may provide a shock absorbing function for the wheel 1300. The wheel 1300 may include a single hub 1312 to which all the flexible spokes 1316 are attached. Alternatively, the wheel 1300 may include a plurality of hub portions, in which case each hub portion is rotatable relative to an adjacent hub portion to facilitate folding and deployment of the wheel 1300 to which one or more spokes 1316 can be attached. As shown in FIGS. 30 and 31, the wheel 1300 may also include a tire 1304, and the tire 1304 may be similar to the exemplary tires disclosed herein.

[0098] Figures 32 and 33 show a wheel 1400 according to another example. The wheel 1400 includes a hub 1412 to which a rim 1418 is attached. The rim 1418 includes a first rim portion 1420 and a second rim portion 1422 that are pivotally attached to the hub 1412 by one or more hinges 1424. As shown in Figure 33, the first rim portion 1420 and the second rim portion 1422 can be pivoted at the hinges 1424 to fold the wheel 1400 from the deployed position shown in Figure 32 to a folded position (not shown). Thus, the size of the wheel 1400 may be reduced for storage and / or transportation when the wheel is folded from the deployed position.

[0099] Referring to Figure 34, a portion of a wheel 1500 according to another example is shown. The wheel 1500 includes at least one spoke 1516 and at least one rim 1518 attached to the spoke 1516. The wheel 1500 may not include an integral tire similar to the examples described above. Instead, a tire portion 1504 is attached to each rim 1518. Thus, when the wheel 1500 is deployed to the deployed position, the tire portion 1504 collectively defines a tire with respect to the wheel 1500. Thus, the tire for the wheel 1500 is defined by a plurality of tire portions 1504 and any gaps that may exist between adjacent tire portions 1504. Similar to the examples described above, the tire portion 1504 may be constructed from an elastic material such as rubber. The tire portion 1504 may then be attached to the rim 1518 with an adhesive, one or more fasteners, and / or one or more other types of attachment devices or procedures.

[0100] Referring to FIGS. 35 - 41, a wheel 1600 according to another example is shown. The wheel 1600 includes a hub assembly 1602. The wheel 1600 may include a tire (not shown) that can be mounted on the hub assembly 1602. Alternatively, the wheel 1600 may include a plurality of tire portions as described above with respect to the wheel 1500. As yet another alternative, the wheel 1600 may operate without a tire. The wheel 1600 also includes an axle 1606 on which the hub assembly 1602 is rotatably mounted. The hub assembly 1602 includes a plurality of wheel portions 1610 that are concentrically mounted on the axle 1606. Each wheel portion 1610 includes a hub portion 1612 having a central bore 1614 for receiving a portion of the axle 1606.

[0101] The wheel 1600 includes a plurality of rims 1618 configured to define a path on a circumferential or circular band 1617 having a width 1619. The path defined by the rims 1618 may be substantially continuous. The circular band 1617 defines a circular contact area similar to a tire (shown in FIG. 38) between the wheel 1600 and the ground. In the deployed position of the wheel 1600, each rim 1618 may be oriented such that at least one point on at least one rim 1618 contacts the ground. In one example, each rim 1618 is positioned obliquely on the circular band 1617. Each rim 1618 may be radially spaced from an adjacent rim 1618 so long as the space does not provide a gap large enough to substantially prevent or impede the wheel 1600 from rotating generally smoothly on the ground. Alternatively, each rim 1618 may not have a radial gap with respect to an adjacent rim 1618. As yet another alternative, each rim 1618 may have a radial overlap with an adjacent rim 1618. In the example of FIG. 38, each rim 1618 has a small gap with respect to an adjacent rim 1618. Also, each rim 1618 may be curved such that points on adjacent rims 1618 spaced at a particular angle are disposed on the circular band 1617. Thus, as shown in FIG. 35, the rims 1618 define a portion of a path on a generally continuous circle in the deployed position of the wheel 1600. In other words, the curvature of each rim 1618 may generally follow the curvature of the circle that defines the plane of the wheel 1600.

[0102] Each rim 1618 is attached to two spaced hub portions 1612 by two respective spokes 1616. The two hub portions 1612 to which the rim 1618 is attached by the spokes 1616 are spaced such that the spokes 1616 form a V-shaped support for each rim 1618. For example, as shown in FIG. 41, the spokes 1616 that support the rim 1618 are spaced only by four hub portions 1612. Thus, each hub portion 1612 has one spoke 1616 on one of its sides that partially supports a first corresponding rim 1618 and another spoke 1616 on the opposite side of it that partially supports a second corresponding rim 1618.

[0103] Figures 35, 36, and 38 show the deployed position of the wheel 1600. When the wheel 1600 is in the deployed position, the spokes 1616 are positioned on the hub portion 1612 such that the spokes 1616 are evenly distributed around the wheel, i.e., equally spaced radially at similar deployment angles. In the example of FIG. 35, the spokes 1616 are shown approximately 30 degrees apart at the deployed position of the wheel 1600. FIGS. 37, 39, and 40 show the folded position of the wheel 1600. To fold the wheel 1600, the hub portions 1612 may be rotated relative to each other until the rims 1618 contact each other and prevent further rotation of the hub portions 1612. Each spoke 1616 may have a particular cross-sectional shape to provide a more compact folded position relative to the wheel 1600. For example, each spoke 1616 may have a diamond-shaped cross-section as shown in FIG. 41. Thus, when the wheel 1600 is folded, each spoke 1616 may be positioned in a complementary or conforming manner relative to the adjacent spoke 1616. Thus, the spokes 1616 may collectively occupy less space compared to a scenario where each spoke 1616 has a particular shape that does not serve such a complementary mating with the adjacent spoke 1616.

[0104] To deploy the wheel 1600, the hub portions 1612 may be rotated in opposite directions relative to each other such that the wheel 1600 reaches the deployed position 1612. Since each spoke 1616 is disposed on a different hub portion 1612, the wheel 1600 may require a rotation of less than 180 degrees to deploy from the folded position to the deployed position, which was described in detail with respect to the wheel 800 and will not be repeated here. Thus, the maximum rotation of the hub portions 1612 may be less than 180 degrees to deploy the wheel 1600 from the folded position to the deployed position.

[0105] When the wheel 1600 reaches the deployed position, the wheel 1600 may include a deployment limiting mechanism as described above to prevent further rotation of the hub portion 1612 relative to each other. Thus each wheel portion 1610 may include a radial slot (not shown) on the hub portion 1612 from 1612, and a pin (not shown) that may be disposed on the hub portion 1612 on the side opposite the slot with respect to the central hole 1614. The arc length of each radial slot may generally be less than or equal to the deployment angle.

[0106] Similar to the example of FIG. 34, each rim 1618 may include a tire portion (not shown) attached to each rim 1618. For example, each tire portion (not shown) may be a generally rectangular strip of rubber or similar elastic material attached to each rim 1618 along the length of the rim 1618. Thus each tire portion generally follows the orientation and spatial position of each rim 1618 on the circular band 1617 as described above. Thus when the wheel 1600 is deployed to the deployed position, the tire portions collectively define the tire of the wheel 1600. Similar to the example described above, the tire portion may be constructed from an elastic material such as rubber. The tire portion may then be attached to the rim 1618 with an adhesive, one or more fasteners, and / or one or more other types of attachment devices or procedures.

[0107] A tire (not shown) may be mounted on the wheel 1600 before and after the wheel is deployed. The tire may be constructed from a solid piece of rubber or other type of plastic material having sufficient elasticity to allow the tire to be mounted on the wheel 1600. Alternatively, the tire may be in the form of an inflatable tube that may be mounted on the rim 1618. As yet another alternative, the tire may be attached to one or more rims 1618 such that the tire is maintained in a configuration mounted on the wheel 1600 at both the folded and deployed positions of the wheel 1600.

[0108] Figures 45-56 illustrate another example of an embodiment of the wheel 1900. The wheel 1900 has a similar structure and / or components as the wheel 100, as well as other embodiments of the wheels described herein. Accordingly, similar terms are used to describe similar components. Referring to FIGS. 45-46, the wheel 1900 includes a hub assembly 1902 that is connected to a tire or track assembly 1904. The track assembly 1904 is a tracked or endless track defined by a plurality of interconnected or interlocking track portions 1905. The track assembly 1904 is connected to the axle 1906 of the hub assembly 1902 by a plurality of wheel portions 1910. The plurality of wheel portions 1910 are aligned and mounted on the axle 1906. Also, it should be understood that the wheel 1900 can be formed from one or more of the wheel portions 110, 610, 810, etc., or aspects or components thereof, as described herein.

[0109] Similar to other embodiments of the wheels disclosed herein, the wheel portions 1910 rotate about the axle 1906 to adjust the wheel 1900 between a deployed position (or deployed configuration) (see FIG. 45) and a folded position (or folded configuration) (see FIG. 46). As illustrated in FIG. 47, folding the wheel 1900 from the deployed position to the folded position achieves a reduction in the height H of the wheel 1900. The reduction in height H can be approximately 35% of the height of the wheel 1900 in the deployed position. However, in other embodiments, the reduction in height H can be any suitable or targeted range of height reduction, including up to a 50% height reduction and / or a 10% height reduction beyond the 50% height reduction. By reducing the wheel height in the folded position, the ground contact area of the wheel 1900 is reduced, which reduces the total space or volume required to store the wheel 1900 (e.g., in a vehicle trunk, garage, basement, luggage, or any other suitable or desired location).

[0110] Figure 48 illustrates an example of one of the wheel portions 1910. The wheel portion 1910 includes a hub portion 1912 that defines a central bore 1914 configured to receive a portion of the axle 1906. The wheel portion 1910 includes a plurality of spokes 1916 that project from the hub portion 1912 to the rim 1918. In the embodiment illustrated in FIG. 48, a first pair of spokes 1916a extend radially from the hub portion 1912 to define a first rim 1918a, while a second pair of spokes 1916b extend radially from the hub portion 1912 to define a second rim 1918b. The first spoke 1916a is positioned on the opposite side of the second spoke 1916b. In other embodiments, each wheel portion 1910 may have any suitable or desired number of spokes 1916 and / or rims 1918. The hub portion 1912 may also include one or more radial slots 1940 that correspond to and function in the same manner as the radial slots 140 (i.e., to limit the rotational distance of the axle 1906 around each wheel portion 1910).

[0111] Figures 49-52 illustrate examples of embodiments of the track portion 1905 used with the wheel 1900. Referring to FIGS. 49-51, each track portion 1905 has a generally arcuate cross-sectional shape for forming the wheel 1900 when a plurality of track portions 1905 are interconnected. The track portion 1905 includes an inner surface 1930 on the opposite side of the outer surface 1932. The inner surface 1930 is configured to engage the wheel portion 1910, while the outer surface 1932 is configured to engage the ground, terrain, or other surface that the wheel 1900 traverses. Thus, the outer surface 1932 has a generally arcuate shape. In the illustrated embodiment, the inner surface 1930 also has a generally arcuate shape. However, the cross-sectional shape of the inner surface 1930 can be any suitable shape for receiving and enabling the rotation of the wheel portion 1910 in accordance with the disclosure provided herein.

[0112] The inner surface 1930 includes a plurality of ribs 1934. The ribs 1934 are substantially parallel to each other and project radially away from the inner surface 1930 to define a plurality of peripheral grooves 1936. Each of the grooves 1936 is configured to receive the rim 1918 of one or more corresponding wheel portions 1910. Thus, the number of grooves 1936 (and thus the number of ribs 1934 that define the grooves 1936) depends on the number of wheel portions 1910 used in the wheel 1900. Any suitable number of grooves 1936 can be defined by each track portion 1905.

[0113] Each track portion 1905 includes a plurality of peripheral protrusions 1950 that define a slot 1954. The protrusions 1950 and the slots 1954 extend circumferentially along the track portion 1905 to facilitate connection with an adjacent track portion 1905. Referring particularly to FIG. 49, the track portion 1905 includes a central member 1958 from which a plurality of protrusions 1950 extend. The central member 1958 includes a first side surface 1962 on the opposite side of the second side surface 1966. The odd-numbered protrusions 1950 extend away from the first side surface 1962 while the even-numbered protrusions 1950 extend away from the second side surface 1966. In the illustrated embodiment, three protrusions 1950 extend circumferentially away from the first side surface 1962 and two protrusions 1950 extend circumferentially away from the second side surface 1966. The adjacent protrusions 1950 on each side surface 1962, 1966 are spaced apart to define the slot 1954. Each slot 1954 is sized and configured to receive a protrusion 1950 from an adjacent track portion 1905. Similarly, each protrusion 1950 is sized to be received by a slot 1954 of an adjacent track portion 1905. To facilitate connection of adjacent track portions 1905, each protrusion 1950 may include an opening 1970 that extends through the protrusion 1950. The openings 1970 are aligned along each side surface 1962, 1966 of the central member 1958 and are configured to receive a dowel, shaft, or other suitable member 1974 (see FIG. 53) to fix or interconnect adjacent track portions 1905.

[0114] When the track portions 1905 are interconnected to define the track assembly 1904, it should be understood that each groove 1936 of the track portions 1905 cooperates with the associated circumferentially aligned groove 1936 of an adjacent track portion 1905 to form a peripheral groove 1936 around the circumference of the wheel 1900. Similarly, each rib 1934 of the track portions 1905 cooperates with the associated circumferentially aligned rib 1934 of an adjacent track portion 1905 to form a peripheral rib 1934 around the circumference of the wheel 1900. The peripheral rib 1934 maintains each wheel portion 1910, and more specifically the rim 1918 of each wheel portion 1910, within the appropriate or associated peripheral groove 1936. Additionally, the peripheral rib 1934 holds one or more of the wheel portions 1910, and more specifically the rims 1918 of those wheel portions 1910, within the appropriate or associated peripheral groove 1936. Thus, as the wheel portions 1910 rotate about the axle 1906 and slide (i.e., move relative thereto) within their respective peripheral grooves 1936, the peripheral rib 1934 helps to keep the wheel portions 1910 within their respective peripheral grooves 1936. In the illustrated embodiment, the rim 1918 has a generally square or rectangular cross-sectional shape when viewed along a cross-section taken in an axial direction parallel to the axle 1906. The groove 1936 has a corresponding cross-sectional shape for receiving the rim 1918 while also allowing the rim 1918 to slide within its respective groove 1936 as the wheel portion 1910 rotates about the axle 1906. In other embodiments, the rim 1918 and the groove 1936 may have any corresponding cross-sectional shape. Generally, the groove 1936 has a shape and / or size corresponding to the shape and / or size of the rim 1918. The groove 1936 can be approximately 0.10 inches to approximately 0.30 inches wide, and more preferably approximately 0.20 inches wide. Each rim 1918 and / or groove 1936 can also be sized to provide sufficient clearance between the rim 1918 and the rib 1934 that defines a portion of the groove 1936 when the rib 1934 is received by the groove 1936.For example, the rim 1918 or the groove 1936 may have a width that provides a gap between the rim 1918 and the rib 1934 of approximately 0.010 inches to approximately 0.030 inches, and more preferably a gap of approximately 0.014 inches between the rim 1918 and the rib 1934.

[0115] FIG. 49 illustrates three protrusions 1950 on the first side 1962 of the central member 1958 and two protrusions 1950 on the second side 1966 of the central member 1958. However, in other embodiments, any number of protrusions may be used. In these other embodiments, however, an odd number of protrusions are provided on one side of the central member 1958 and an even number of protrusions are provided on the other opposite side of the central member 1958. For example, one side of the central member 1958 may have 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, etc. protrusions 1950, while the other side of the central member 1958 may have 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, etc. protrusions 1950. Generally, one side of the central member 1958 will have N protrusions 1950, while the other opposite side of the central member 1958 will have N - 1 (or N + 1) protrusions 1950. The track portion 1905 is defined as above with respect to the protrusions 1950, but the track portion 1905 may be defined similarly with respect to the slots 1954. The track portion 1905 may have an even number of slots 1954 on the first side 1962 of the central member 1958 and an odd number of slots 1954 on the second side 1966 of the central member 1958. Generally, one side of the central member 1958 will have N slots 1954, while the other opposite side of the central member 1958 will have N - 1 (or N + 1) slots 1954.

[0116] Returning to FIG. 50 for reference, each track portion 1905 can have any number of ribs 1934 and any number of grooves 1936. In the illustrated embodiment, each track portion 1905 includes nine ribs 1934 and eight grooves 1936. In other embodiments, each track portion 1905 can include any number of ribs 1934, such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or more. Further, in other embodiments, each track portion 1905 can include any number of grooves 1936, such as 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or more. The number of grooves 1936 generally corresponds to the number of wheel portions 1910 (since each groove 1936 receives at least one wheel portion 1910). In addition, each track portion 1905 can have any suitable distribution of ribs 1934 and grooves 1936 on the protrusions 1950. For example, in the illustrated embodiment, a plurality of protrusions 1950 have two ribs 1934 that define at least one groove 1936 and a portion of a second groove 1936, while one protrusion 1950 (the central protrusion 1950 protruding on the first side 1962 of the central member 1958) has one rib 1934 that defines a portion of two grooves 1936. However, in other embodiments, the protrusions 1950 can have any suitable or desired number of ribs and / or channels (or portions thereof). Further, the protrusions 1950 can have different numbers of ribs 1934 and / or channels 1936 (e.g., one protrusion 1950 can have two ribs 1934 while another protrusion 1950 can have five ribs). Thus, any suitable or desired number of ribs 1934 and / or grooves 1936 can be positioned on each protrusion 1950.

[0117] Each rib 1934 has a rib height 1978. In the illustrated embodiment, the rib height 1978 is substantially constant because the rib 1934 extends from the central member 1958. However, when the rib 1934 reaches the end of the protrusion 1950 on the opposite side of the central member 1958, the rib height 1978 decreases or has a curved end portion 1982. The curved portion 1982 helps to avoid contact with the rib 1934 of the adjacent track portion 1905 when all the track portions 1905 are interconnected to form the wheel 1900.

[0118] Referring to FIGS. 53-54, a plurality of track portions 1905 are connected together to form a track assembly 1904, and only a portion thereof is shown. As previously disclosed, the track portions 1905 are connected by a fixing member 1974 received by an opening 1970 in the protrusion 1950. Any suitable fixing member 1974 may be used, but preferably the track portion 1905 can rotate around the fixing member 1974 to facilitate folding of the wheel 1900.

[0119] FIGS. 53-54 illustrate a portion 1986 of a track assembly 1904 formed by three track portions 1905. Any suitable number of track portions 1905 may be interconnected to form the track assembly 1904. For example, as illustrated in FIGS. 45-46, twenty-four track portions 1905 define a track assembly 1904 that forms a wheel 1900. In other words, each track portion 1905 extends along the wheel 1900 by approximately 15 degrees (15°) (i.e., 360 degrees divided by 24 track portions). In other embodiments, each track portion 1905 may extend along the wheel 1900 by any suitable number of degrees. In other words, any number of track portions 1905 may be interconnected to form the wheel 1900.

[0120] When the wheel 1900 is in the folded position, at least one wheel part 1910a is fixed or attached to a part 1986 of the track assembly 1904 to fix the track assembly 1904 to the hub assembly 1902. In other words, the wheel part 1910a is not configured to slide within the associated groove 1936 of the track assembly 1904. FIGS. 53-54 illustrate a part 1986 of the track assembly 1904 that is fixed to the wheel part 1910a. This part 1986 includes a plurality of openings 1988 defined by associated deployment portions or protrusions 1989 that project from the ribs 1934 (or the edges of the ribs 1934) on both sides of the groove 1936. The openings 1988 are coaxially aligned on the side surfaces of the groove 1936. The opening or rim opening 1990 is defined by a part 1991 of the rim 1918 of the wheel part 1910a (shown in FIG. 55). When the rim 1918 of the wheel part 1910a is positioned within the groove 1936 (such that the groove 1936 receives the rim 1918), the rim opening 1990 is positioned in alignment with each respective opening 1988 on the rib 1934. A fixing member 1992 (shown in FIGS. 58-59) is received by the aligned openings 1988, 1990 to fix a part 1986 of the track assembly 1904 (and thus the track assembly 1904) to the wheel part 1910a. By the fixing, the wheel part 1910a does not slide within the groove 1936 of the track assembly 1904. Other embodiments of the wheel 1900 may include a plurality of wheel parts 1910a that are fixed to the groove 1936 of the track assembly 1904 and do not slide therein. Additionally, any one or more of the grooves 1936 may be configured to fix the track assembly 1904 to the hub assembly 1902. Thus, any one or more of the grooves 1936 may include a plurality of protrusions 1989 that project from the opposing ribs 1934 and define the openings 1988.

[0121] As shown in FIG. 56, a plurality of spacers 1996 can be positioned along the axle 1906 between adjacent wheel portions 1910. The spacer 1996 can have a central bore 1997 that receives a portion of the axle 1906, and radial slots 1998 that are shaped and aligned (when assembled) with the radial slots 1940. The spacer 1996 is composed of or coated with polytetrafluoroethylene (PTFE) or a related polymer to reduce friction between the wheel portions 1910 when the wheel portions 1910 are rotated about the axle between the deployed and folded positions. Additionally, the spacer 1996 can help maintain proper spacing of the wheel portions 1910 within the hub assembly 1902.

[0122] Also, FIGS. 45 - 46 are to be understood as illustrating that four track portions 1905 engage or otherwise connect to each wheel portion 1910 when in the deployed position. In other embodiments, any number of track portions 1905 can be associated with each wheel portion 1910 (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc.).

[0123] FIGS. 57 - 63 illustrate an alternative embodiment of a wheel 1900a that is substantially the same as the wheel 1900. Accordingly, like parts of the wheel 1900 and the wheel 1900a are referenced using the same reference numbers. The wheel 1900a includes a track assembly 1904 defined by a plurality of interlocking track portions 1905a. Additionally, the axle 1906 also carries an end member or sprocket 1999.

[0124] Figures 62-63 illustrate an example of a track portion 1905a used to define a track assembly 1904 of a wheel 1900a. The track portion 1905a is similar to the track portion 1905, and like parts are referenced using the same reference numbers. The track portion 1905a includes two protrusions 1950 on a first side surface 1962 of a central member 1958 and a single protrusion 1950 on a second side surface 1966 of the central member 1958. Thus, the two protrusions 1950 define one slot 1954 on the first side surface 1962, while there are two slots 1954 on the second side surface 1966. Referring to FIG. 63, the track portion 1905a defines the same number of ribs 1934 and grooves 1936 across the width of the track portion 1905a as the track portion 1905. However, the distribution of the ribs 1934 and grooves 1936 on each protrusion 1950 of the track portion 1905a is different from that of the track portion 1905. More specifically, each of the two protrusions 1950 on the first side surface 1962 of the central member 1958 includes two ribs 1934, each defining a part of one groove 1936 and a second groove 1936. The single protrusion 1950 on the second side surface 1966 of the central member 1958 includes five ribs 1934 and defines four grooves 1936. To carry additional ribs 1934 and grooves 1936, the single protrusion 1950 on the second side surface 1966 of the central member 1958 has a greater width than each of the two protrusions 1950 on the first side surface 1962 of the central member 1958. In other embodiments of the track portion, each protrusion 1950 may have the same width or different widths. Further, each protrusion 1950 on a common side surface 1962, 1966 may have the same width or different widths. Additionally, in other embodiments, the number of ribs 1934 and grooves 1936 (or portions thereof) may vary or be different on each protrusion 1950. It should be understood that any number of ribs 1934 and / or grooves 1936 may be implemented or used in the wheels 1900, 1900a.

[0125] During operation, the wheel 1900 can be adjusted between a deployed position (shown in FIG. 45) and a folded position (shown in FIG. 46). To adjust the wheel 1900 between positions, the user can rotate the hub assembly 1902, such as by applying a rotational force to the handles 202, 204 of the hub cap 200. Rotation of the hub cap 200 rotates the wheel portion 1910 about the axle 1906 and slides the wheel portion 1910 (and more specifically the rim 1918) within a corresponding groove 1936 defined by the track portion 1905 of the track assembly 1904. It should be understood that while the wheel portion 1910 rotates about the axle 1906, at least one wheel portion 1910a does not rotate because it is fixed to a portion of the track assembly 1904. This helps maintain the connection between the hub assembly 1902 and the track assembly 1904 (such that the track assembly 1904 does not disengage from the hub assembly 1902 during adjustment between the deployed and folded positions).

[0126] As the wheel portion 1910 slides within the groove 1936 of the track assembly 1904 toward the folded position, the wheel portion 1910 disengages and no longer supports a portion of the track assembly 1904. When the wheel portion 1910 rotates and aligns about the axle 1906 (see FIG. 46), the portion of the track assembly 1904 that is no longer supported by the wheel portion 1910 folds, deforming the wheel 1900 to the folded position.

[0127] When the wheel portion 1910 slides toward a deployed position within the groove 1936 of the track assembly 1904, the wheel portion 1910 engages and supports a portion of the track assembly 1904. The slots 1940 and 1998 provide the same function as the slot 140 and help guide the distance and amount of rotation of the wheel portion 1910 about the axle 1906. When the wheel portion 1910 is rotated completely separately about the axle 1906 (see FIG. 45), the wheel 1900 is in the deployed position. This arrangement advantageously deploys the wheel portion 1910 without requiring any additional user interaction. Additionally, the spaced-apart wheel portions 1910 maintain the circular shape (i.e., 360 degrees) of the wheel 1900 and maintain a constant contact with the ground (or other surface engaged by the terrain or track assembly 1904).

[0128] Referring to FIG. 42, a method 1700 for constructing a wheel according to an example is shown. The method includes forming a plurality of wheel parts (block 1702) and assembling the wheel parts onto an axle (block 1704). The method 1700 may also include forming a tire (not shown) and / or mounting or attaching the tire onto the wheel parts (not shown) and / or mounting or attaching a truck assembly onto the wheel parts (not shown). The wheels according to the present disclosure may be constructed from any metal or metal alloy, plastic, composite material, wood, or combinations thereof. For example, each wheel part such as the wheel part 110 of the wheel 100 may be integrally formed from a plastic material by injection molding. In the injection molding process, a mold having a cavity defining the wheel part may be used. The molten plastic material is injected into the mold and cooled. The formed and cooled wheel part is then removed from the mold. Also, the formed wheel part may be smoothed or cleaned to remove residues of the injection molding. Alternatively, the wheel part may be constructed by stamping (i.e., punching, blanking, coining, bending, flanging, embossing, or casting using a mechanical press or a stamping press), forging, machining, or combinations thereof, or other processes used to manufacture metal, composite, plastic, or wood parts. Each wheel part may be integrally formed. Alternatively, the components of each wheel part may be formed by the processes and materials described herein and assembled to form the wheel part. For example, the wheel part 110 may be formed by assembling individually manufactured hub part 212, spokes 216, and rim 218. The hub part 212, one or more spokes 216, and the rim 218 may be attached to each other by one or more adhesives, welding, soldering, and / or fasteners. Any of the disclosed wheel, axle, and / or tire components may be manufactured using the disclosed materials and / or processes. The tire may be manufactured from an elastic material to provide shock absorption to a handcart to which one or more of the disclosed wheels are attached. The tire may be formed from rubber or other plastic materials.The tire may be formed as an inflatable tube or a solid flexible material.

[0129] Referring to FIG. 43, a golf push cart 1800 for supporting and transporting a golf club bag is shown having wheels 100. Although the push cart 1800 is shown with wheels 100, any of the wheels described herein may be used with a golf push cart. The golf push cart 1800 may include a frame 1810 on which a golf club bag (not shown) may be placed. The golf club bag may also be supported by a bottom support 1812, a bottom side support 1813, and a top side support 1814. The frame 1810 may also include one or more straps (not shown) for securing the golf club bag to the frame 1810. The push cart 1800 may further include two feet 1820 and 1822 that extend outwardly from the frame 1810 on opposite sides of each other. Each foot supports a wheel 100. The frame may also include a hinge 1824 having two hinge rods 1826 and 1828 such that the feet 1820 and 1822 may pivot and fold along the frame 1810. The frame 1810 may also be folded at the hinge to provide a compact golf push cart 1800 for traveling on a golf course, driving range, or any golf-related facility. The folded golf push cart 1800 is shown in FIG. 44. To further reduce the size of the golf push cart 1800, the wheels 100 may be folded as detailed herein. Additionally, the wheels 100 may be removed from the push cart 1800 and stored individually. Thus, the size of any vehicle, such as a golf push cart, may be reduced using the wheels 100 or any of the wheels described herein to facilitate storage and / or transportation. Alternatively, a golf club bag (not shown) may include attachment points or axles for directly attaching two foldable wheels to the golf club bag as detailed herein. For example, a golf club bag may be provided with two foldable wheels that may be stored within one or more pockets of the golf club bag.A person may carry the golf club bag, or attach two wheels to an axle on the golf club bag, deploy the wheels, and pull the golf club bag by using the wheels. The use of foldable wheels as detailed herein is not limited to golf push carts. The foldable wheels as detailed herein may be used on a kayak cart, a shopping cart, a small wagon typically used by children, any type of travel bag, a cart for travel bags, a cooler and / or any other utility cart with wheels, a trailer, an enclosed storage device, or a vehicle.

[0130] Referring to FIGS. 64 - 68, a wheel 2000 according to another example is shown. The wheel 2000 includes a hub assembly 2002. The hub assembly 2002 includes a plurality of spokes 2016 that extend radially from a hub portion 2012. The hub portion 2012, the spokes 2016, and the rim 2018 may form a wheel plane. The wheel 2000 is configured such that the hub portion, the spokes, and the rim do not rotate relative to each other. By varying the length of the spokes, the rim 2018 may be moved towards or away from the hub portion.

[0131] The wheel diameter may be measured in the wheel plane from a first outer edge of the rim 2018 through the center of the wheel to a second outer edge of the rim 2018 on the side opposite the first outer edge. The wheel 2000 may also include an axle 2006 (not shown) to which the hub assembly 2002 is rotatably mounted. The wheel 2000 may include a tire (not shown) attachable to the hub assembly 2002. Alternatively, the wheel 2000 may include a plurality of tire portions as described above with respect to the wheel 1500. As yet another alternative, the wheel 2000 may operate without a tire.

[0132] The wheel 2000 may include a plurality of rims 2018 that can be configured to define a path on a circumferential or circular band (not shown) having a width. The rim width can be measured in a direction toward the center of the wheel within the wheel plane. The width can vary along each rim 2018 or can be constant along each rim 2018. The path defined by the rims 2018 may be substantially continuous. The circular band defines a circular contact area similar to a tire between the wheel 2000 and the ground. In one example, each rim 2018 is disposed in the exact same plane as the circular band. In the deployed position of the wheel 2000, each rim 2018 may be oriented such that at least one point on at least one rim 2018 contacts the ground plane simultaneously. In some embodiments, there are several orientations of the wheel 2000 such that at least one point on at least two rims contacts the ground plane simultaneously.

[0133] In some embodiments, as in the example of FIG. 64, in the deployed position, each rim 2018 may have a radial overlap with an adjacent rim 2018. Each rim 2018 may be radially spaced from an adjacent rim 2018 as long as the space does not provide a gap large enough to substantially prevent or impede the wheel 2000 from rotating generally smoothly on the ground. Alternatively, each rim 2018 may not have a radial gap with an adjacent rim. Each rim 2018 may be curved such that points on adjacent rims 2018 spaced at a particular angle are disposed on the circular band 2017. Thus, as shown in FIG. 64, the rims 2018 define a part of a path on a generally continuous circle in the deployed position of the wheel 2000. In other words, the curvature of each rim 2018 in the deployed position may generally follow the curvature of the circle defining the plane of the wheel 2000.

[0134] Each rim 2018 is attached to a central hub portion 2012 by at least one spoke 2016. In some embodiments, there may be the same number of rims 2018 and spokes 2016. For example, in FIG. 64, there are four rims 2018 and four spokes 2016. In other embodiments, there may be at least two spokes 2016. For example, the wheel 2000 may include one spoke, two spokes, three spokes, four spokes, five spokes, six spokes, seven spokes, eight spokes, nine spokes, or ten or more spokes. Each spoke 2016 includes an inner spoke portion 2015 and an outer spoke portion 2019 that is received by the inner spoke portion 2015 when moving from an extended position to a folded position.

[0135] Each rim 2018 may include at least one thin peripheral region 2023. In many embodiments, each rim 2018 includes a central portion and two end portions. The rim 2018 may include a first end portion 2023a and a second end portion 2023b. In both the folded configuration and the deployed configuration, the first end portion 2023a of one rim 2018 may overlap the second end portion 2023b of an adjacent rim 2018. There may be more overlapping portions of adjacent rims 2018 when the wheel 2000 is in the folded configuration than when the wheel 2000 is in the deployed configuration. At least one of the two peripheral regions may include a thin peripheral region. The width of the rim measured in a direction perpendicular to the wheel plane is smaller in the thin peripheral region than in the central portion. In some embodiments, as shown in FIGS. 64 and 65, in order to form the thin peripheral region 2023, a recess may be defined by one surface of the rim 2018 on each end of each rim 2018. In some of the above embodiments, both of the thin peripheral regions 2023 are on the same surface of the rim 2018. In other embodiments, the thin peripheral region 2023 is on a different surface of the rim 2018. In the deployed configuration and the folded configuration, at least a part of the thin peripheral region 2023 of one rim 2018 may overlap a part of the thin peripheral region 2023 of an adjacent rim 2018. In some embodiments, the adjacent thin peripheral regions 2023 may overlap only in the folded configuration, not in the deployed configuration. The thin peripheral regions 2023 of two adjacent rims 2018 may overlap along the recess 2023 in a different way in the folded configuration than in the deployed configuration. As shown in FIG. 68, in the folded configuration, the rim 2018 may overlap an adjacent rim 2018 and extend beyond the adjacent rim 2018.

[0136] Referring to FIGS. 66 and 67, the diameter D of the wheel 2000 in the folded configuration C is the diameter D of the wheel 2000 in the deployed configuration EIt can be smaller. The diameter of the wheel can be reduced between 15% and 30%. The diameter can be reduced by 15% - 20%, 20% - 25%, or 25% - 30%. For example, in some embodiments, the diameter of the wheel 2000 is reduced by approximately 22%. In the folded position, the surface area of the wheel 2000 can be reduced between 30% and 50%. For example, the surface area of the wheel 2000 can be reduced between 30% - 35%, 35% - 40%, 40% - 45%, or 45% - 50%. In one example, in the folded configuration, the surface area of the wheel 2000 can be reduced by 39%. In the deployed configuration and the folded configuration, the width of the wheel 2000 can remain the same.

[0137] To deploy the wheel 2000, the spokes 2016 can be extended. When switching the wheel 2000 from the folded configuration to the deployed configuration or from the deployed configuration to the folded configuration, the outer spoke portion 2019 is slidable relative to the inner spoke portion 2015. In some embodiments, the spokes 2016 can be extended by applying a force in a direction away from the hub portion 2012 to at least one of the spokes 2016. Alternatively, the wheel 2000 can be deployed by rotating a central hub portion attachment (not shown). Even when changing from the folded position to the deployed position, the hub portion 2012, the spokes 2016, and the rim 2018 can continue to be in substantially the same plane.

[0138] To prevent further extension of the spokes after the wheel 2000 has reached the deployed position, the wheel 2000 may include a deployment limiting mechanism. In some embodiments, a locking mechanism may serve as the deployment limiting mechanism. The deployment limiting mechanism may be engaged to prevent the wheel 2000 from returning to the folded position during use. In some embodiments, once the wheel 2000 has reached the deployed position, the deployment limiting mechanism may automatically engage. In other embodiments, the deployment limiting mechanism may be manually engaged at any point during spoke extension to maintain any desired wheel diameter. The user can unlock the wheel by performing an operation on a component, such as pushing, twisting, pulling, or moving one or more components of the locking mechanism to unlock it.

[0139] Referring to FIGS. 69 and 70, the central hub portion 2112 may include an extension system. The extension system is a mechanism responsible for enabling the spokes 2116 to extend. The extension system may include at least one spoke extension 2120. The first end 2122 of the spoke extension 2120 may be rotatably attached to the central hub portion 2112. The inner end of each spoke 2116 may be rotatably fastened to the second end 2124 of the spoke extension 2120. In the deployed position, the spoke extension 2120 forms part of the spoke and is incorporated into the length of the spoke. In many embodiments, as shown in FIG. 69, in the folded configuration, the spoke extension 2120 forms an acute angle with the spoke 2116. When moving from the folded configuration to the deployed configuration, the extension 2120 rotates about their second ends 2124 and moves away from the center of the hub portion 2112. In some embodiments, when moving from the folded configuration to the deployed configuration, the extension 2120 may rotate between 15 degrees and 40 degrees. For example, the extension may rotate between 15 degrees and 20 degrees, between 20 degrees and 25 degrees, between 25 degrees and 30 degrees, between 30 degrees and 35 degrees, or between 35 degrees and 40 degrees. In some embodiments, as shown in FIG. 70, in the deployed configuration, the spoke extension 2120 forms an obtuse angle with the spoke 2116. In some embodiments, in the deployed position, the spoke extension 2120 forms an angle of 180 degrees with the spoke 2116. The angle between the spoke extension 2120 and the spoke 2116 is greater in the folded position than in the deployed position.

[0140] Similar to the example of FIG. 34, each rim 2018, 2118 may include a tire portion (not shown) attached to each rim 2018, 2118. For example, each tire portion may be a generally rectangular strip of rubber or similar elastic material attached to each rim 2018, 2118 along the length of the rims 2018, 2118. Thus each tire portion generally follows the orientation and spatial position of each rim 2018, 2118 on the circular band as described above. Thus when the wheels 2000, 2100 are deployed to the deployed position, the tire portions collectively define the tires of the wheel 1600. Similar to the example described above, the tire portion may be constructed from an elastic material such as rubber. The tire portion may then be attached to the rims 2018, 2118 with an adhesive, one or more fasteners, and / or one or more other types of attachment devices or procedures.

[0141] A tire (not shown) may be mounted on the wheel 2000 both before and after the wheel is deployed. The tire may be constructed from a solid piece of rubber or other type of plastic material having sufficient elasticity to allow the tire to be mounted on the wheel 2000. Alternatively, the tire may be in the form of an inflatable tube that may be mounted on the rim 2018. As yet another alternative, the tire may be attached to one or more rims 2018 such that the tire is maintained in a configuration mounted on the wheel 2000 at both the folded and deployed positions of the wheel 2000.

[0142] Referring to FIG. 71, a wheel 2200 according to another embodiment is shown. This wheel may be similar to wheel 2100 in many respects. Wheel 2200 includes a locking system. The locking system may include a locking element 2221 accessible from the outside and at least one hole 2225 capable of receiving the locking element 2221 accessible from the outside. The locking mechanism may be operated by engaging / disengaging, operating, or installing / removing the locking element accessible from the outside. The locking element 2221 of the wheel 2200 is a threaded screw 2227. Other embodiments may include different externally accessible locking elements such as buttons, pins, clamps, or other fasteners. The holes 2225 of the wheel 2100 are positioned in each spoke 2216. In other embodiments, the holes 2225 may be present in the hub assembly 2202, the spokes 2216, or the rim. When the wheel 2100 is in the deployed configuration, the spokes 2216 may be mechanically locked. In some of these embodiments, when the wheel 2200 is in the folded configuration, the spokes 2216 may be mechanically locked. In the locked state, the outer spoke portion 2219 is not slidable relative to the inner spoke portion 2215, so the spoke 2216 cannot be deployed or folded. To deploy or fold the wheel 2200, the wheel must be unlocked. To unlock the wheel 2200, the user moves the locking element 2221 in a direction away from the wheel, thereby releasing it from the locked position. The threaded screw 2227 can be moved by being twisted in one direction until it is released from the hole 2225. Once released, the outer spoke portion becomes slidable relative to the inner spoke portion. To lock the wheel 2200, the screw can be twisted in a second direction to engage the desired hole 2225.

[0143] Referring to FIG. 72, a wheel 2300 according to another embodiment is shown. This wheel may be similar to wheel 2100 in many respects. Similar to wheel 2100, wheel 2300 includes a locking system. The locking system may include a locking element 2321 accessible from the outside and at least one hole 2325 capable of receiving the locking element 2321 accessible from the outside. The locking mechanism may be operated by a locking element accessible from the outside. The locking element 2321 of the wheel 2300 is a spring plunger 2327. Other embodiments may include different externally accessible locking elements such as buttons, pins, clamps, or other fasteners. Each spoke 2316 includes at least one hole 2325. In other embodiments, the holes may be present in the hub assembly, the spokes, or the rim. When the wheel 2300 is in the deployed configuration, the spokes 2316 may be mechanically locked. In some of these embodiments, the spokes 2316 may be mechanically locked when the wheel 2300 is in the folded configuration. In the locked state, the outer spoke portion 2319 is not slidable relative to the inner spoke portion 2315, so the spoke 2316 cannot be deployed or folded. To deploy or fold the wheel 2200, the wheel must be unlocked. To unlock the wheel, the user moves the locking element 2321 away from the wheel 2300, thereby releasing it from the locked position. The spring plunger 2327 can be moved by being lifted away from the spoke 2316 until it is released from the hole 2325. Once released, the outer spoke portion 2319 becomes slidable relative to the inner spoke portion 2315. To lock the wheel 2300, the spring plunger 2327 is released from the lifted position and can engage the desired hole 2325.

[0144] Referring to FIGS. 73-77, a wheel 2400 according to another example is shown. The wheel 2400 includes a hub assembly 2402. The hub assembly 2402 may include a plurality of spokes 2416 that extend radially from a hub portion 2412. Each spoke 2416 of the plurality of spokes may be attached to a rim 2418. In some embodiments, each spoke 2416 of the plurality of spokes may be attached to two or more rims 2418. In other embodiments, two or more of the plurality of spokes 2416 may be attached to one and the same rim or a plurality of the same rims 2418. The wheel 2400 is configured such that the hub portion and the spokes do not rotate relative to each other. However, the rim may be partially rotatable relative to the spokes when switching between a folded configuration and a deployed configuration.

[0145] The hub assembly 2402, the spokes 2416, and the rim 2018 may form a wheel plane. The wheel diameter may be measured in the wheel plane from a first outer edge of the rim 2018 through the center of the wheel to a second outer edge of the rim 2018 on the side opposite the first outer edge. The wheel 2400 may include a tire (not shown) attachable to the hub assembly 2402. Alternatively, the wheel 2400 may include a plurality of tire portions as described above with respect to the wheel 1500. As yet another alternative, the wheel 2400 may operate without a tire. The wheel 2400 may also include an axle (not shown) to which the hub assembly 2402 is rotatably attached.

[0146] Wheel 2400 includes a plurality of rims 2418 configured to define a path on a circumferential or circular band having a width. The width may vary along each rim 2418 or may remain constant along each rim 2418. The path defined by the rims 2418 may be substantially continuous. The circular band may define a circular contact area similar to a tire between the wheel 2400 and the ground. In one example, each rim 2418 is positioned in the exact same plane as the circular band. In the deployed position of the wheel 2400, each rim 2418 may be oriented such that at least one point on at least one rim 2418 contacts the ground. In some embodiments, there are some orientations of the wheel 2400 such that at least one point on at least two rims contacts the ground plane simultaneously.

[0147] In some embodiments, as in the example of FIG. 73, in the deployed position, each rim 2418 may have a radial overlap with an adjacent rim 2418. Each rim 2418 may be radially spaced from an adjacent rim 2418, provided that the space does not provide a gap large enough to substantially prevent or impede the wheel 2400 from rotating generally smoothly on the ground. Alternatively, each rim 2418 may not have a radial gap with an adjacent rim. Each rim 2418 may be curved such that points on adjacent rims 2418 spaced at a particular angle are disposed on the circular band 2417. Thus, as shown in FIG. 73, the rims 2418 define a part of a path on a generally continuous circle in the deployed position of the wheel 2400. In other words, the curvature of each rim 2418 in the deployed position may generally follow the curvature of the circle that defines the plane of the wheel 2400.

[0148] Each rim 2418 is attached to the central hub portion 2412 by at least one spoke 2416. In some embodiments, there may be the same number of rims 2418 and spokes 2416. For example, there may be four rims 2018 and four spokes 2016. In many embodiments, there may be at least two spokes 2416. In some examples, the wheel 2400 may include two spokes, four spokes, six spokes, eight spokes, ten spokes, twelve spokes, fourteen spokes, or sixteen spokes.

[0149] The wheel 2400 may include at least one first spoke 2430 and at least one second spoke 2432. Each first spoke 2430 may include a first inner spoke portion 2433 and a first outer spoke portion 2435. Each first outer spoke portion 2435 is slidably received by the first inner spoke portion 2433 when moving from the deployed position to the folded position. Each second spoke 2432 may include a second inner spoke portion 2443 and a second outer spoke portion 2445. Each second outer spoke portion 2445 is slidably received by the second inner spoke portion 2443 when moving from the deployed position to the folded position.

[0150] The first spoke 2430 and the second spoke 2432 may have different cross-sectional shapes and widths. In other embodiments, the first spoke 2430 and the second spoke 2432 may have the same cross-sectional shape. In the embodiments shown in FIGS. 73-77, the first spoke 2430 has a rectangular cross-section, while the second spoke 2432 has a circular cross-section. In other embodiments, the first spoke 2430 and the second spoke 2432 may have any cross-sectional shape among rectangles, ellipses, circles, or other polygons. The cross-sectional width of the first spoke may be larger than the cross-sectional diameter of the second spoke. The first spoke 2430 and the second spoke 2432 may have substantially the same length. One end of each rim is attached to the first spoke, and the other end is attached to the second spoke. The outermost end of each first outer spoke portion 2435 may be fixed to at least one rim 2418 so as to be fixedly or hingedly connected. In some embodiments, the rim 2418 may rotate about the attachment point with the first spoke 2430. The outermost end of each second outer spoke portion 2445 may be slidably attached to at least one rim 2418. As an example, in the embodiment shown in FIG. 69, each first spoke 2430 is attached to two rims 2418, and each second spoke 2432 is attached to two rims 2430.

[0151] Each rim 2418 may include an elongated notch 2450. In some embodiments, as shown in FIGS. 73-77, the notch 2423 penetrates the rim near the end. In both the folded configuration and the deployed configuration, a portion of the notch 2423 of one rim 2418 may overlap a portion of the notch 2423 of an adjacent rim 2418. The notches 2423 of two adjacent rims 2418 may overlap at different points along the notch 2423, when in the folded configuration and when in the deployed configuration. As shown in FIG. 74, in the folded configuration, the rim 2418 may overlap and extend beyond an adjacent rim 2418. In most of these embodiments, the rim 2418 may define a circle in the deployed configuration, but not in the folded configuration.

[0152] To deploy the wheel 2400, the spokes 2430, 2432 may be extended. When switching the wheel 2400 from the folded configuration to the deployed configuration or from the deployed configuration to the folded configuration, the outer spoke portions 2435, 2445 are slidable relative to the inner spoke portions 2433, 2443. By applying a force in a direction away from the hub portion 2412 to at least one spoke 2416, the spokes 2430, 2432 may be extended. Even when changing from the folded position to the deployed position, the hub portion 2412, the spokes 2430, 2432, and the rim 2418 may remain substantially in the same plane.

[0153] Referring to FIGS. 75 and 76, the diameter DC of the wheel 2400 in the folded configuration can be smaller than the diameter DE of the wheel 2400 in the deployed configuration. The diameter of the wheel can be reduced by between 20% and 50%. For example, in some embodiments, the diameter of the wheel 2400 is reduced by approximately 35%. The surface area of the wheel 2400 can be reduced by between 50% and 70%. For example, the surface area of the wheel 2400 can be reduced between 50% - 55%, 55% - 60%, 60% - 65%, or 65% - 70%. In some embodiments, in the folded configuration, the surface area of the wheel 2400 can be reduced by approximately 57%. The width of the wheel 2400 can remain the same in both the deployed and folded configurations.

[0154] To deploy the wheel 2400, the spokes 2416 can be extended. When switching the wheel 2400 from the folded configuration to the deployed configuration or from the deployed configuration to the folded configuration, the outer spoke portion is slidable relative to the inner spoke portion. By applying a force in a direction away from the hub portion 2412 to at least one spoke 2416, the spoke can be extended. Even when changing from the folded position to the deployed position, the hub portion 2412, the spokes 2416, and the rim 2418 can continue to be in substantially the same plane.

[0155] The central hub portion of the wheel 2400 can include an extension system that governs the ability of the spokes to extend and fold. Referring to FIGS. 69 and 70, the extension system of the wheel 2400 can be substantially similar to the extension system of the wheel 2100 disclosed above.

[0156] To prevent further extension of the spokes after the wheel 2400 reaches the deployed position, the wheel 2400 may include a deployment limiting mechanism. The deployment limiting mechanism of the wheel 2400 can be substantially similar to the deployment limiting mechanism of the wheel 2000 disclosed above.

[0157] Wheel 2400 may further include a locking mechanism that prevents folding or unfolding of the wheel 2400 during use. Referring to FIGS. 71 and 72, the locking mechanism of wheel 2400 may be substantially similar to the locking mechanism of wheel 2200 or wheel 2300.

[0158] Similar to the example of FIG. 34, each rim 2418 may include a tire portion (not shown) attached to each rim 2418. For example, each tire portion may be a generally rectangular strip of rubber or similar elastic material attached to each rim 2418 along the length of the rim 2418. Thus, each tire portion generally follows the orientation and spatial position of each rim 2418 on the circular band as described above. Thus, when the wheel 2400 is deployed to the deployed position, the tire portions collectively define the tires of the wheel 1600. Similar to the example described above, the tire portion may be constructed from an elastic material such as rubber. The tire portion may then be attached to the rim 2418 with an adhesive, one or more fasteners, and / or one or more other types of attachment devices or procedures.

[0159] A tire (not shown) may be mounted on the wheel 2400 before and after the wheel is deployed. The tire may be constructed from a solid piece of rubber or other type of plastic material that has sufficient elasticity to allow the tire to be mounted on the wheel 2400. Alternatively, the tire may be in the form of an inflatable tube that may be mounted on the rim 2418. As yet another alternative, the tire may be attached to one or more rims 2418 such that it is maintained in a configuration where it is mounted on the wheel 2400 in both the folded and deployed positions of the tire.

[0160] Referring to FIGS. 78 and 79, a wheel 2500 according to another example is shown. Certain aspects of the wheel 2500 may be similar to the wheel 100 shown in FIGS. 1-3. Accordingly, similar parts of the wheel 100 and the wheel 2500 are designated with similar reference numerals. The wheel 2500 includes a hub assembly 2502 and an axle 2506 on which the hub assembly 2502 is rotatably mounted.

[0161] Figures 78 and 79 each show the wheel 2500 in the deployed position and the folded position. Similar to the embodiments of FIGS. 1 - 3, each wheel portion 2510 may be freely rotatable about the axle 2506 so that the wheel portion 2510 can be deployed from the folded position to the deployed position. In the folded configuration, the surface area of one side of the wheel 2500 can be reduced between 40% and 60% relative to the surface area of one side of the wheel 2500 in the deployed configuration. For example, the surface area of the wheel in the folded configuration can be reduced between 40% - 45%, between 45% - 50%, between 50% - 55%, or between 55% - 60%. In some embodiments, in the folded configuration, the surface area of the wheel 2500 can be reduced by approximately 52%.

[0162] The hub assembly 2502 includes a plurality of stacked wheel portions 2510. Each wheel portion 2510 includes a hub portion 2512 with a central hole 2514. The wheel portions 2510 may be concentrically stacked such that the central holes 2514 are axially aligned to form an elongated hole for receiving the axle 2506. Each wheel portion 2510 may include spokes 2516 and a rim 2518. In the examples of FIGS. 78 - 80, each wheel portion 2510 has a first spoke 2516 that radially projects from the hub portion 2512 for connecting to the first rim 2518, and further has a second spoke 2516 that radially projects from the hub portion 2512 on the side opposite the first spoke 2516 for connecting to the second rim 2518. Each wheel portion 2510 may include any number of spokes 2516 that extend from the hub portion 2512 to one or more rims 2518. In some embodiments, each wheel portion may include one spoke, two spokes, three spokes, or four spokes that extend from the hub portion 2512 to one or more rims 2518.

[0163] The spokes 2516 may be of any shape. For example, each spoke 2516 may be straight, bent at one or more locations along the length of the spoke, and / or have a curved portion. In the examples of FIGS. 78-80, the spokes 2516 may be curved so as to function as springs when the wheel 2500 is in use. Thus, when a force is applied to the rim 2518 during operation of the wheel 2500, the curved shape of each spoke 2516 facilitates elastic bending of the spoke 2516 such that the spoke 2516 provides a shock-absorbing function. The curvature of the spokes 2516 may be in the shape of an "S", as in the examples of FIGS. 78-80, or may be a combination of straight and curved portions. The cross-section of the spokes 2516 may be of any shape. For example, the cross-section of the spokes 2516 may be square, rectangular, circular, hexagonal, or any other polygon.

[0164] Increasing the number of contact points between the wheel 2500 and the ground may increase the stability of the wheel 2500. Each rim 2518 may contact the ground at one contact point. By providing a plurality of contact points that contact the ground at all times, i.e., a plurality of rims 2518, the stability of the wheel 2500 may increase. In other words, by increasing the number of contact points with the ground at all times during operation of the wheel 2500, the width of the wheel 2500 increases, thereby increasing the number of wheel portions 2510 that can be used to form the wheel 2500. By increasing the number of wheel portions 2510, the stability of the wheel 2500 and / or the weight that the wheel 2500 can support may increase. However, increasing the number of wheel portions 2510 may also increase the size and / or weight of the wheel 2500 in the folded position. Thus, the size of each wheel portion 2510 and the other characteristics of each wheel portion 2510 as described herein may be determined depending on the size and load of the cart to which one or more wheels 2500 can be attached.

[0165] Figures 78 - 80 show a wheel 2500 having tire portions on each rim 2518. When the wheel 2500 is deployed to the deployed position, the tire portions 2504 collectively define the tire of the wheel 2500. Thus, the tire of the wheel 2500 is defined by the plurality of tire portions 2504 and any gaps that may exist between adjacent tire portions 2504. The tire portion can be constructed from any durable material. In some examples, the tire portion can be constructed from an elastic material such as rubber or plastic. In some embodiments, the tire portion can be integrally attached to the rim 2518. In other embodiments, the tire portion can be attached to the rim 2518 by an adhesive, mechanical fastener, molding, or bonding.

[0166] A particular order of acts has been described above, but these acts may be performed in other time series. For example, the plurality of acts described above may be performed sequentially, in parallel, or simultaneously. Alternatively, the plurality of acts may be performed in the reverse order. Further, one or more of the acts described above may not be performed at all. The apparatus, methods, and articles of manufacture described herein are not limited in this regard.

[0167] Although the invention has been described in various aspects, it will be understood that the invention is further modifiable. This application includes any variations, uses, or adaptations of the following invention, generally including the principles of the invention, and departures from the present disclosure within the known and customary scope of practice in the art to which the invention pertains. Claim 1: A wheel comprising a hub portion defining a rotation axis, a plurality of spokes extending from the hub, and a plurality of rim portions, each of the plurality of spokes having an inner spoke portion and an outer spoke portion, each inner spoke portion being configured to receive one outer spoke portion, each of the plurality of spokes engaging at least one of the plurality of rim portions, the plurality of rim portions defining a circle in a deployed configuration, the plurality of rim portions defining a rotation plane, the rim portions having a thickness measured in a direction orthogonal to the rotation plane, each of the plurality of rim portions having a central portion and two end portions, the thickness of the two end portions of each of the plurality of rim portions being thinner than the thickness of the central portion, and in a folded configuration, a first end portion of each rim portion overlapping a second end portion of an adjacent rim portion, the foldable wheel being configured in a deployed configuration or a folded configuration.

[0168] Claim 2: The wheel according to Claim 1, wherein in both the deployed configuration and the folded configuration, a part of two adjacent rim portions of the plurality of rim portions overlaps each other.

[0169] Claim 3: The wheel according to Claim 2, wherein the overlapping portion of adjacent rim portions is larger in the folded configuration than in the deployed configuration.

[0170] Claim 4: Further comprising an axle, the axle being configured to removably receive the hub portion of each wheel portion by being insertable into a central hole of each wheel portion concentric with the rotation axis of the wheel portion, the wheel being rotatable relative to the axle, the wheel according to Claim 1.

[0171] Claim 5: The wheel according to Claim 1, wherein the plurality of rims define a circle in the deployed configuration.

[0172] Claim 6: The wheel according to Claim 5, wherein in the folded configuration, each rim of the plurality of rims defines a segment of the circle defined in the deployed configuration.

[0173] Claim 7: The wheel according to claim 1, wherein each end defines a recess, and each recess in a single rim is defined in the same plane of the rim.

[0174] Claim 8: The wheel according to claim 7, wherein the recesses of adjacent rims are defined in opposite planes of the rim.

[0175] Claim 9: The wheel according to claim 1, wherein the hub and the inner spoke portion are integrally formed, and at least one outer spoke portion and at least one rim portion are integrally formed.

[0176] Claim 10: The wheel according to claim 1, further comprising a tire configured to be attachable to the rim portion in the folded configuration or the deployed configuration.

[0177] Claim 11: The wheel according to claim 10, wherein each rim portion comprises a tire portion.

[0178] Claim 12: The wheel according to claim 1, wherein the hub portion, the plurality of spokes, and the rim portion are non-rotatable relative to each other.

[0179] Claim 13: The wheel according to claim 13, wherein each spoke is attached to one rim portion at the central portion of the rim portion.

Claims

1. a hub portion defining a rotational axis, a plurality of spokes extending from the hub, and a plurality of rim portions, each of the plurality of spokes having an inner spoke portion and an outer spoke portion, each inner spoke portion being configured to receive one outer spoke portion, each of the plurality of spokes engaging at least one of the plurality of rim portions, the plurality of rim portions defining a circle in the deployed configuration, the plurality of rim portions defining a plane of rotation, the rim portions having a thickness measured in a direction orthogonal to the plane of rotation, each of the plurality of rim portions having a central portion and two end portions, the thickness of the two end portions of each of the plurality of rim portions being thinner than the thickness of the central portion, in the folded configuration, the first end portion of each rim portion overlapping the second end portion of an adjacent rim portion, the foldable wheel being configurable in a deployed configuration or a folded configuration, a wheel.

2. The wheel according to claim 1, wherein in both the deployed configuration and the folded configuration, a part of two adjacent rim portions of the plurality of rim portions overlap each other.

3. The wheel according to claim 2, wherein the overlapping portion of adjacent rim portions is larger in the folded configuration than in the deployed configuration.

4. further comprising an axle, the axle being configured to removably receive the hub portion of each wheel portion by being insertable into a central hole of each wheel portion concentric with the rotational axis of the wheel portion, the wheel being rotatable relative to the axle, the wheel according to claim 1.

5. The wheel according to claim 1, wherein the plurality of rims define a circle in the deployed configuration.

6. The wheel according to claim 5, wherein in the folded configuration, each rim of the plurality of rims defines a segment of the circle defined in the deployed configuration.

7. each end portion defining a recess, each recess in a single rim being defined in the same plane of the rim, the wheel according to claim 1.

8. The wheel according to claim 7, wherein the recesses of adjacent rims are defined in opposite planes of the rims.

9. the hub and the inner spoke portion being integrally formed, The wheel according to claim 1, wherein at least one outer spoke portion and at least one rim portion are integrally formed.

10. The wheel according to claim 1, further comprising a tire configured to be attachable to the rim portion in the folded configuration or the deployed configuration.

11. The wheel according to claim 10, wherein each rim portion comprises a tire portion.

12. The wheel according to claim 1, wherein the hub portion, the plurality of spokes, and the rim portion are non-rotatable relative to each other.

13. The wheel according to claim 1, wherein each spoke is attached to one rim portion at the central portion of the rim portion.

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