Foldable wheel

The present invention provides a foldable wheel which can greatly reduce its size and be carried conveniently, comprising: an extendable hub including a first end and a second end, wherein the distance between the first end and the second end may be changed by adjusting the extendable hub; a plurality of extendable spokes each including a first extendable portion and a second extendable portion, wherein the first extendable portion connects with the first end of the extendable hub and the second extendable portion connects with the second end of the extendable hub, and the first extendable portion connects with the second extendable portion by a first connector; and a plurality of the second connectors connected with the plurality of extendable spokes for connecting to a rim.

CROSS-REFERENCE TO RELATED APPLICATION

This present application claims priority to TAIWAN Patent Application Serial Number 099125813, filed Aug. 3, 2010, which is herein incorporated by reference.

TECHNICAL FIELD

The present invention is generally related to a wheel. More particularly, the present invention is directed towards a foldable wheel.

BACKGROUND OF THE RELATED ART

As the oil price rises rapidly, the cost of vehicle and motorcycle transport is increased. By contrast, using bicycles addresses low-cost transport, saves money, and improves health and environmental protection. As a result, demand for bicycles has increased constantly in recent years and bicycles become the most popular means of transport.

However, bicycle needs not to be registered as vehicle does, and bicycle is much lighter than vehicle. Hence, the bicycle is more likely to be stolen and is unlikely to be found. For improving these drawbacks, many kinds of foldable bicycle have been developed in prior art to facilitate folding, storing and transporting. For example, the U.S. Pat. No. 7,198,281 disclosed that a foldable bicycle10as FIG. lA and1B shown. To eliminate the description of unnecessary details, only specific embodiment and elements of the prior art is described as follow.

FIG. 1Billustrates the unfolded state of bicycle10. It substantially comprises a front portion11and a rear portion12which comprise a wheel20respectively. The front portion11and the rear portion12are pivotally connected by a folding joint31and a detachable connecting joint32.FIG. 1Billustrates the folded state of bicycle10. Thus it can be seen that the front portion11and the rear portion12can be folded up by means of the folding joint31and the detachable connecting joint32for the purpose of saving space. Most prior arts, for instance U.S. Pat. No. 7,198,281 or any similar foldable bicycle, provide a foldable bicycle main body by means of improving the structure of the main body. However, asFIG. 1Bshown, in the unfolded state, the wheels20of the bicycle are so large that they take up space. Thus, there is still room for improvement in space saving for bicycle storage. In other prior art, there is a foldable bicycle with mini wheels (e.g. wheel diameter is relative small) to saving the space taken by the wheel. But small-diameter wheels may influence the performance of bicycle.

As mentioned above, the prior arts have disclosed the structure of foldable bicycle for the purpose of saving space. But, in the prior art, the wheels are unfoldable and the bicycle cannot save the space taken by the wheels. Furthermore, the size of the wheels may influence the performance of bicycle and the convenience of folding and carrying of bicycle. Such indispensable factor is a dilemma of designing bicycle.

SUMMARY

For solving these problems, the present invention is direct toward a foldable wheel which provides good performance as big wheel and also provides ideal space-saving storage.

One purpose of the present invention is to provide a foldable wheel, which can be folded for easy carrying and space-saving storage. However, the present invention can be applied to, but be not limited to, toy, bicycle, motorcycle, car, airplane or a combination thereof, or any apparatus with wheels.

For achieving the purpose, one aspect of the present invention is to provide a foldable wheel, which comprises at least a plurality of extendable spokes and either an extendable hub or a fixed hub. Some embodiments are stated below. The hub may include a first end and a second end, wherein the distance between the first end and the second end may be changed by adjusting the extendable hub; a plurality of first connecting mechanisms placed on the first end of the hub; a plurality of second connecting mechanisms placed on the second end of the hub; a plurality of extendable spokes each including a first extendable portion, a second extendable portion and a first connector, wherein the first extendable portion connects with the first connecting mechanism and the first connector, and the second extendable portion connects with the second connecting mechanism and the first connector; the distance between the first connecting mechanism and the first connector may be changed by adjusting the first extendable portion, and the second connecting mechanism and the first connector may be changed by adjusting the second extendable portion, wherein the first extendable portion and the second extendable portion can relatively rotate about the first connector in order to enable the plurality of extendable spokes to be folded or unfolded by the plurality of first connectors; and a plurality of second connectors connected with the plurality of extendable spokes for connecting to a rim.

In other aspect of the present invention, it is to provide a foldable device comprising a main body, and at least one foldable wheel as mentioned above.

In another aspect of the present invention, it is to provide a method for folding the foldable wheel as mentioned, which comprises: expanding or nesting the extendable hub to enable increasing or decreasing the distance between the first end of the extendable hub and the second end of the extendable hub; unfolding the plurality of extendable spokes connecting with the extendable hub toward the extendable hub; and possibly followed or preceded by contracting the extendable hub and the plurality of extendable spokes to reduce space occupation of the hub and spokes.

In another aspect of the present invention, it is to provide a method for unfolding the foldable wheel as mentioned, which comprises: expanding the extendable hub and the plurality of extendable spokes to enable the first end relatively far from the second end and increase the length of extendable hub and the extendable spokes; contracting the extendable hub to push the first connector of the spokes from the extendable hub; and enabling the rim to directly or indirectly connect with the plurality of first connectors by using the plurality of second connectors.

DETAILED DESCRIPTION

While the invention has been described by way of examples and in terms of preferred embodiments, it is to be understood that the invention is not limited thereto. Hence the present invention may be applied in various modifications other than the embodiment.

The present invention will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements. The main characters of the embodiment will be illustrated in clear and simple way. Besides, not all of the characters of the embodiment have shown in figures. The figures included herein are illustrated diagrammatically and not drawn to scale, as they are provided as qualitative illustration of the concept of the present invention.

FIG. 2A to 2Fare schematic illustration showing a foldable wheel according to an embodiment of the invention. InFIG. 2A, a foldable wheel200comprises an extendable hub202. The extendable hub202comprises a first end202band a second end202cwherein the relative distance between the first end202band the second end202ccan be adjusted by expanding and contracting the extendable hub202. It will be described in detail below. The foldable wheel200also comprises a plurality of first connecting mechanisms204placed on the first end202b, and a plurality of second connecting mechanisms206placed on the second end202c.

AsFIG. 2A to 2Fshown, in one of the embodiments, extendable hub202is cylinder, and the first end202band the second end202cof the extendable hub202are arranged in substantially symmetry. AsFIG. 2Dshown, in one embodiment, the fist end202bincludes a plurality of first connecting mechanisms206which are averagely placed around the cylinder of the first end202bnear the edge of plane. The second end202calso includes a plurality of second connecting mechanisms206which are also placed on the second end202cin the same or similar way. The foldable wheel200includes a plurality of extendable spokes208. In one of the embodiments, the number of the first connecting mechanism204, the second connecting mechanism206and the extendable spokes208to be placed may respectively be, but not limited, to eight.

In another embodiment of the present invention, the foldable wheel comprises a hub, a plurality of extendable spokes connected to the hub, and a plurality of connectors connected to one end of the hub opposed to the plurality of extendable spokes for connecting to a rim, wherein the relative distance between the plurality of connectors and the hub can be adjusted by expanding and contracting the plurality of extendable spokes.

The extendable spokes208respectively comprises a first extendable portion208a, a second extendable portion208band a first connector208c, wherein the first extendable portion208aconnected to the first connecting mechanism204and the first connector208c, and the second extendable portion208bconnected to the second connecting mechanism206and the first connector208c. The relative distance between the first connecting mechanism204and the first connector208ccan be adjusted by expanding and contracting the first extendable portion208a, and the relative distance between the second connecting mechanism206and the first connector208ccan be adjusted by expanding and contracting the second extendable portion208b. In addition, the first extendable portion208aand the second extendable portion208bcan be relatively rotate around the first connector208cto fold or unfold the plurality of extendable spokes208based on the first connector208c.

In one embodiment of the present invention, the first connector208cis used to connect the first extendable portion208ato the second extendable portion208b, and fold or unfold the extendable spokes208by relatively rotating the first end202band the second end202cof the extendable hub202and changing the relative position of them. Hence, the first connector208cof the present invention includes every kind of machinery and element for the purpose mentioned above. It is noted that the embodiments and the figures described herein are for illustration only and do not limit the spirit and scope of the invention. Those skilled in the art readily will appreciate that various changes and modifications can be made within the spirit and scope of the present invention, as defined by the following Claims.

AsFIG. 2Ashown, the foldable wheel200also comprises a plurality of second connectors210connected to a plurality of extendable spokes208for connecting with a rim212. In one embodiment of the present invention, the rim212includes a plurality of rim portions212awhich can be configured in accordance with the number and length of extendable spokes202. In the preferred embodiment, a plurality of rim portions212arespectively comprises a first rim connective portion212band a second rim connective portion212c. The first rim connective portion212bcomprises a tenon and a groove matching with a groove and a tenon of the second rim connective portion212cfor the purpose of assembling the plurality of same rim portions212alike building block and forming the rim212. In some embodiment, the rim portion212amay comprise a steel ring portion212dand a tire portion212e. The steel ring portion212dmay be made of hardened material, but hardened metal is better. The tire portion212emay be made of elastic material. It may be a solid elastic structure or an inflatable hollow structure. In general, there is tread pattern on the outward surface of the tire portion212efor increasing traction of wheel. In the preferred embodiment, asFIG. 2B and 2Cshown, a plurality of second connectors210may be pins for inserting into retaining hole inside of the rim212and enabling the extendable spokes208to connect with rim212.

Please referring toFIG. 2E, it illustrates an unfolding state of the foldable wheel of the present invention. In an embodiment of the present invention, extendable hub202further comprises a first hub portion202a, a second hub portion202d, a third hub portion202e, a forth hub portion202fand a fifth hub portion202g, wherein the second hub portion202dand the third hub portion202esubstantially symmetrically nest in the first hub portion202aand are able to expand and contract from the first hub portion202a. In addition, the forth hub portion202fand the fifth hub portion202grespectively nest in the second hub portion202dand the third hub portion202e. The forth hub portion202fand the fifth hub portion202gare substantially symmetrically disposed and able to expand and contract from the first hub portion202a. In the unfolding state of the foldable wheel200, the extendable hub202is in contractive state, as a result, in outward appearance, other hub portions are received and hided in the first hub portion202a, asFIG. 2Ashown. In some embodiment, the bores of the second hub portion202dand the third hub portion202eare smaller than the bore of the first hub portion202a, and the bores of the forth hub portion202fand the fifth hub portion202gare respectively smaller than the bores of the second hub portion202dand the third hub portion202e. Furthermore, in different embodiment, the bores of the second hub portion202dand the third hub portion202emay be same or different. Similarly, the bores of the forth hub portion202fand the fifth hub portion202gmay be same or different.

In the embodiment of the present invention, it provides an extendable hub202with a hub retaining element which enables to retain and lock the extendable hub202as the extendable hub202in contractive state (i.e. the first end202band the second end202care located at relatively near distance). It is used to keep the first end202band the second end202cat relatively near distance and facilitate to increase the stability of extendable hub202. Please referring toFIG. 5, it illustrates a machinery exploded figure showing an extendable hub202. It only shows one of the first end202band the second end202cbecause the ends are configured substantially symmetrically. As the figure shown, the extendable hub202comprises the first hub portion202a, the third hub portion202eand the fifth hub portion202g. It only describes part of the extendable hub202because the third hub portion202eand the fifth hub portion202gare respectively taken as the second hub portion202dand the forth hub portion202f.

The extendable hub202further comprises a wheel cap202hand a cylinder202i, wherein the cylinder202iis vertically connected to the central position of the wheel cap202hand one end of the cylinder202iis with a thread of a screw. The fifth hub portion202gcomprises a via hole202jwhich is facilitate the cylinder202ito insert in. And in the inward part of the first hub portion, it comprises a locking apparatus202kwhich includes a thread of a screw corresponding to the thread of cylinder202ifor the purpose of retaining each other. In addition, the first hub portion202afurther comprises a supporting configuration202l, a connecting and locking configuration202kand the inner wall of the first nub portion202awhich enable the connecting and locking configuration disposed on the first hub portion202a. As a result, when the extendable hub202is contracted, the cylinder202iis rotated and locked with connecting and locking configuration202kby rotating the wheel cap202hfor the purpose of enhancing the retaining function. One end of the third hub portion202eincludes a first tenon202mcorresponding to a first block board202oin the inward part of both ends of the first hub portion202a. The first tenon202mis used to prevent the third hub portion202eand the second hub portion202dfrom departing from the first hub portion202awhen the extendable hub202is expanding. Similarly, one end of the fifth hub portion202gincludes a second tenon202ncorresponding to a second block board202pin the inward part of the third hub portion202eand the second hub portion202d. The second tenon202nis used to prevent the fifth hub portion202gfrom departing from the third hub portion202eand the second hub portion202dwhen the extendable hub202is expanding.

Alternatively, all the hub portions may form as taper and two ends of the extendable hub202are also formed as taper in order to prevent the hubs portion from falling off. In one of the embodiments, the cylinder202imay connect to an elastic element202q, such as a spring, to keep the extendable hub202in expanding state or contractive state without external force. For example, using the elastic element202qto keep the extendable hub202in contractive state, then in step302or402, the user only need to turn on the wheel cap202hand the elastic element202qsprings the first end202band the second end202cto the relatively far away.

Please referringFIG. 6, it illustrates another embodiment of the present invention which provides another hub retaining element to keep the first end202band the second end202cat multiple specific distances. About the locking method for the extendable hub202in contractive state, it only describes part of extendable hub202for illustration because the hubs are configured substantially symmetrically. The third hub portion202eand the fifth hub portion202gare respectively taken as the second hub portion202dand the forth hub portion202f. AsFIG. 6shown, the inward part of the first hub portion202acomprises at least one slotted track202rand one end of the slotted track202rconnected to a crooked slot202sand sequentially connected to a locking slot202t. The outward part of the third hub portion202ecomprises at least one salient202uwhich matches the slotted track202rand is used to engage in the slotted track202r, the crooked slot202sand the locking slot202t. The number of the slotted track202rof the first hub portion202aand the salient202uof the third hub portion202eto be configured may be, but not limited, to four.

By means of the hub retaining element, as contracting the extendable hub202and relatively rotating the third hub portion202eand the first hub portion202a, it enables the salient202uto engage into the crooked slot202sand further into the locking slot202t. The salient202ualso includes a spring or other elastic element connecting with two ends, wherein one of the ends is connected to the third hub portion202e(or the second hub portion202d) for promoting the salient202uto auto-engage in the locking slot202tafter passing through the crooked slot202s. As expanding the extendable hub202, the user only needs to perform the steps in opposite direction. Similarly, the inward part of the third hub portion202ecomprises similar slotted track202r, crooked slot202sand locking slot202t. The outward part of the fifth hub portion202galso comprises similar salient202uand springs for similar function.

In one embodiment of the present invention, the first extendable portion208aand the extendable portion208bof the extendable spoke208respectively comprise a first spoke portion208d, a second spoke portion208eand a third spoke portion208f, wherein the bore of the second spoke portion208eis smaller than the bore of the first spoke portion208d, and the bore of the third spoke portion208fis smaller than the bore of the second spoke portion208e. As a result, the second spoke portion208eis able to nest in the first spoke portion208d, and the third spoke portion208fis able to nest in the second spoke portion208e. These three spoke portions co-form an expandable and contractible structure. In another embodiment of the present invention, the first extendable portion208aand the extendable portion208bof the extendable spoke208may respectively comprise the first spoke portion208dand the second spoke portion208e, wherein the bore of the second spoke portion208eis smaller than the bore of the first spoke portion208d, and the second spoke portion208eis able to nest in the first spoke portion208d.

In one embodiment of the present invention, each two of the first spoke portion208d, the second spoke portion208eand the third spoke portion208fmay include a retaining mechanism, asFIG. 7A,7B and7C shown. InFIG. 7A, every two portions may include corresponding screw threads208ito achieve the function of retaining the position. InFIG. 7B, it may be retained by means of V-shaped tenons208gwith springs. V-shaped tenons208gare similar in principle to S-shaped tenons208hwhich are enabling the each two portion moveable or un-moveable by means of pressing or moving the tenons to adjust the position.

In the one of the embodiments, the V-shaped tenons208gor the S-shaped tenons208henable the each two portion un-moveable without external force. It may choose the V-shaped tenons208gor the S-shaped tenons according to the bore size, the amount of force or other factors. TheFIG. 7A to 7Cmay be considered to provide a retaining mechanism for spokes which keeps the extendable spokes208in specific length. In addition, the extendable spokes208also can be retained by the configuration shown inFIG. 6; that is to say, retaining the extendable spokes208by slots and salient.

One aspect of the present invention is to provide a foldable apparatus comprising: a main body and at least a foldable wheel200mentioned above. The apparatus may be the bicycle10as the prior art, or other apparatus such as toy, bicycle, motorcycle, car, airplane or a combination thereof, or any apparatus with wheels.

The present invention also provides a method300for folding the wheel, and a method400for unfolding the wheel which the procedures are illustrated inFIG. 2andFIG. 4. AsFIG. 3shown, a method300for folding the wheel comprises: step302for expanding the extendable hub202to enable increasing the distance between the first end202bof the extendable hub202and the second end202cof the extendable hub202; step304for folding the plurality of extendable spokes208toward the extendable hub202; and step306for contracting the extendable hub202and the plurality of extendable spokes208to reduce space occupation of the hub202and spokes208. In the other aspect, a method400for unfolding the wheel comprises: step402for expanding the extendable hub202and the plurality of extendable spokes208to enable the first end202brelatively far from the second end202cand increase the length of hub202and the spokes208; step404for contracting the extendable hub202to push the first connector208cof the spokes208from the extendable hub202; and step406for enabling the rim212to directly or indirectly connect with the plurality of first connectors208cby using the plurality of second connectors210.

As illustrated above, it should be appreciated that the foldable wheel200in unfolding state shown inFIG. 1Acan be folded to the state asFIG. 2Fshown by the method illustrated inFIG. 3. Furthermore, by means of steps302and304, the foldable wheel200can transit from the state inFIG. 2Ato the state inFIG. 2E. By step306, the foldable wheel200can transit from the state inFIG. 2Eto the state inFIG. 2F. Conversely, by step402, the foldable wheel200can transit from the state inFIG. 2Fto the state inFIG. 2E. By steps404and406, the foldable wheel200can transit from the state inFIG. 2Eto the state inFIG. 2A. It is noted that the angle form by the extendable spokes208after folding is not limited the angle shown inFIG. 2F. The skilled in the art readily will appreciate that the extendable spokes208may substantially form a straight angle after folding the foldable wheel200by means of adjusting the length ratio of the extendable hub202and the extendable spokes208. The angle shown inFIG. 2Fis just for illustration purpose, not limited in this invention.

One advantage of the present invention is that the foldable wheel200can be applied in relative large wheel diameter and provide good performance as big wheel. It can also transit to folding state by the folding method300for easy carrying and space-saving storage.

The other advantage of the present invention is that the foldable wheel200can be storage in folding state. As a result, the foldable wheel200is convenient for carry and taken as a spare tire.

The other advantage of the present invention is multi-directional space-saving by the extendable hub202and the extendable spokes208, not single directional space-saving.

Another advantage of the present invention is simplified the procedure for operating the extendable hub202and the extendable spokes208.

Another advantage of the present invention is to enhance the structural stability of the foldable wheel200by the hub retaining elements and/or spoke retaining mechanisms and enable the foldable wheel200to apply in different apparatus.

The extendable spokes208described in one of the embodiments can be broadly applied in toy, bicycle, motorcycle, car, airplane or a combination thereof, or any apparatus with wheels. For the purpose of complete and easy illustration, well-known elements have not been described in detail to avoid unnecessarily obscuring the present invention. However, the well-known elements or procedures which are necessary for practicing the present invention are still included in the embodiments of the present invention. For example, the long axis of symmetry of the extendable hub202may comprises a via hole (not shown in figures) for installing the foldable wheel200in bicycle or any apparatus with wheels (for example motorcycle, car, airplane, toy or a combination thereof, other traffic tool or non-traffic tool. InFIG. 5, the axial diameter of the cylinder202ican be designed longer to provide space for disposing via holes. Alternatively, it can dispose the bulging ends on two ends of the extendable hub202and install the extendable hub202in bicycle or other apparatus by the bulging ends. For the purpose of complete and easy illustration, the figures included herein are illustrated diagrammatically and not drawn to scale, as they are provided as qualitative illustration of the concept of the present invention. The scope of the present invention is expressly not limited expect as specified in the accompanying claims. Various changes and modifications can be made within the spirit and scope of the present invention, as defined by the following claims.