WO2011151612A1

WO2011151612A1 - Folding bicycle

Info

Publication number: WO2011151612A1
Application number: PCT/GB2011/000706
Authority: WO
Inventors: David Houghton
Original assignee: Fisher Outdor Leisure Limited
Priority date: 2010-06-04
Filing date: 2011-05-06
Publication date: 2011-12-08
Also published as: GB201009439D0; GB2472887A; GB2472887B

Abstract

A folding bicycle (100) is disclosed, the bicycle comprising a first frame section (102, 108) and a second frame section (104, 110) movably mounted to the first frame section. The first and second frame sections may be moved relative to each other from an unfolded position to a folded position. The bicycle also includes a latching mechanism (130) having a latch member (200) attached to one of the first frame section and the second frame section. The latch member (200) is adapted to form an interlocking engagement with an engaging part (302) of the other of the first frame section and the second frame section when the first and second frame sections are in the folded state, so as to hold the first and second frame sections in the folded state. The first frame section comprises a front strut (102) movably mounted to the second frame section and a front fork (108) rotatably mounted to the front strut (102). The latch member (200) is adapted to form an interlocking engagement with the engaging part (302) in response to rotation of the front fork (108) relative to the front strut (102) when the first and second frame sections are in the folded state. A method for folding and securing the folding bicycle is also disclosed.

Description

Folding bicycle

The invention relates to a folding bicycle having a latching mechanism for holding the bicycle in its folded state for transport. .

Folding bicycles typically have a hinge formed roughly in the middle of the bicycle frame, between the saddle and the handlebars. The hinge allows the frame to be folded by rotating a front section of the frame relative to the rear section of the frame so that the two sections of the frame lie alongside each other. A locking mechanism is provided to hold the bicycle in the unfolded state, preventing the frame sections from rotating relative to one another when the bicycle is being ridden. In the folded state, the front section of the frame is roughly parallel to the rear section of the frame and the front and rear wheels of the bicycle are side by side. Thus, the length of the bicycle is halved and it becomes easier to carry the bicycle in the boot of a car or on public transport.

There is a problem with existing folding bicycles in that they are not securely held in the folded state. The frame may start to rotate back to the unfolded state due to the bicycle being knocked or shaken during transport, which makes the bicycle more awkward to carry and can lead to the bicycle being damaged.

An object of the present invention is therefore to provide a means of securing a folding bicycle in its folded state so that it can be transported more easily and safely.

According to an aspect of the present invention, there is provided a folding bicycle comprising: a first frame section; a second frame section movably mounted to the first frame section so that the first and second frame sections may be moved relative to each other from an unfolded position to a folded position; and a latching mechanism having a latch member attached to one of the first frame section and the second frame section; wherein the latch member is adapted to form an interlocking engagement with an engaging part of the other of the first frame section and the second frame section when the first and second frame sections are in the folded state, so as to hold the first and second frame sections in the folded state; wherein the first frame section comprises a front strut movably mounted to the second frame section and a front fork rotatably mounted to the front strut; and wherein the latch member is adapted to form an interlocking engagement with the engaging part in response to rotation of the front fork relative to the front strut when the first and second frame sections are in the folded state.

The folding bicycle according to the invention is securely held in the folded state by the interlocking engagement between the latch member on one frame section and the engaging part on the other frame section.

Since the latch member engages with the engaging part in response to rotation of the front fork, the folding bicycle can be latched in the folded state simply by rotating the front fork via the handle bars once the frame has been folded. Thus, the bicycle can be secured in the folded state quickly and conveniently and the folding process is not significantly lengthened by the latching step.

Suitably, one of the latch member and the engaging part is mounted on the front fork. Conveniently, the front fork has an axle mounting at a lower end thereof, and the one of the latch member and the engaging part is mounted adjacent the lower end of the front fork.

Preferably, the folding bicycle further comprises a tab fixed to the front fork, wherein the one of the latch member and the engaging part is mounted on the tab.

Preferably, the folding bicycle further comprises a handle section including a handle shaft and handle bars mounted to an upper end of the handle shaft so as to be substantially perpendicular to the handle shaft, wherein a lower end of the handle shaft is mounted to an upper end of the front fork. Suitably, the lower end of the handle shaft is rotatably mounted to the upper end of the front fork via a front hinge, so that the handle shaft and the front fork can be rotated relative to each other from an unfolded state to a folded state. Conveniently, when the handle shaft and the front fork are in the unfolded state the lower end of the handle shaft is below its upper end, and when the handle shaft and the front fork are in the folded state the upper end of the handle shaft is below its lower end, using a direction from a lower end to the upper end of the front fork as a reference upwards direction. Suitably, the second frame section comprises a rear strut movably mounted to the first frame section and seat stays fixed to the rear strut. Preferably, the seat stays have a drop out at a lower end thereof, and one of the latch member and the engaging part is mounted on the drop out.

Conveniently, the second frame section is rotatably mounted to the first frame section. Preferably, a rear end of the first frame section is mounted to a front end of the second frame section, when the first and second frame sections are in the unfolded state the rear end of the first frame section is rearward of its front end, and when the first and second frame sections are in the folded state the rear end of the first frame section is forward of its front end, using a direction from a rear end to the front end of the second frame section as a reference forwards direction. Suitably, the second frame section is mounted to the first frame section by a central hinge allowing rotation of the second frame section relative to the first frame section about an axis.

Preferably, the latch member comprises a clip having a recess adapted to

accommodate the engaging part. Suitably, the clip is formed from a resilient material and the engaging part is a force fit to the recess. Preferably, the recess has an opening facing towards the rear of the bicycle when the first frame section and the second frame section are in the unfolded state.

In one embodiment, the engaging part comprises a stud. Suitably, the stud is mounted to the other of the first frame section and the second frame section by at least one threaded shaft and a screw drive socket is formed in a head of the stud. Preferably, the stud is a ball stud and the recess is adapted to accommodate a neck of the ball stud. More preferably, a cup-shaped concave portion is formed in the clip, the concave portion being arranged to accommodate part of the head of the ball stud when the neck of the ball stud is accommodated in the recess.

Suitably, the latch member is adjustably mounted to the one of the first frame section and the second frame section. Preferably, the latch member is attached to the one of the first frame section and the second frame section by at least one bolt passing through a hole in the latch member and a corresponding hole in the one of the first frame section and the second frame section, and at least one of the holes is elongated so as to allow the attachment position of the latch member to be adjusted.

In one embodiment, the engaging part is adjustably mounted to a main part of the other of the first frame section and the second frame section. Preferably, the engaging part is attached to the main part by a threaded shaft passing through a hole in the main part, and the hole is elongated so as to allow the attachment position of the engaging part to be adjusted.

According to another aspect of the present invention, there is provided a method of folding and securing the folding bicycle described above, the method comprising:

moving the first frame section from the unfolded position to the folded position relative to the second frame section; and rotating the front fork relative to the front strut so as to bring the latch member into interlocking engagement with the engaging part, thereby holding the first and second frame sections in the folded position.

The method of the present invention folds and secures the bicycle quickly and conveniently. The step of rotating the front fork so as to engage the latch member and the engaging part is particularly easy to perform and requires no additional moving parts because it is the same motion as steering the bicycle.

Preferably, the rotating step is performed by rotating the handle bars relative to the front strut.

Rotating the front fork by rotating the handle bars uses the handle bars as a lever to apply more torque to the front fork. This in turn increases the force with which the latch member is brought into engagement with the engaging part relative to the force applied to the handle bars by the user of the bicycle. Hence, a strong holding force can be provided by the engagement between the latch member and the engaging part without requiring great strength on the part of the user to perform the engaging step.

Suitably, the method further comprises an initial step of rotating the front fork to a first orientation relative to the front strut, wherein when the first and second frame sections are in the folded position and the front fork is in the first orientation the latch member does not engage with the engaging part.

Embodiments of the present invention will now be described by way of further example only and with reference to the accompanying drawings, in which:

Fig. 1 is a schematic side view of the frame of a folding bicycle 100 according to an embodiment of the invention in the unfolded state;

Fig. 2 is a schematic overhead view of the frame of a folding bicycle 100 according to an embodiment of the invention in the folded state;

Fig. 3 is a perspective view of the latching mechanism 130 of a folding bicycle 100 according to an embodiment of the invention in an unlatched state;

Fig. 4 is another perspective view of the latching mechanism 130 of a folding bicycle

100 according to an embodiment of the invention in the unlatched state;

Fig. 5 is an overhead view of the latching mechanism 130 of a folding bicycle 100 according to an embodiment of the invention in a latched state;

Fig. 6 is a perspective view of the latching mechanism 130 of a folding bicycle 100 according to an embodiment of the invention in the latched state;

Fig. 7 is a perspective view of a clip 202 forming part of the latching mechanism 130 of a folding bicycle 100 according to an embodiment of the invention; and

Fig. 8 is a perspective view of a clip forming part of the latching mechanism 130 of a folding bicycle 100 according to another embodiment of the invention.

Fig. 9 is a perspective view of a ball stud 302 forming part of the latching mechanism

130 of a folding bicycle 100 according to an embodiment of the invention.

In this description, a longitudinal horizontal direction X is defined as the direction of a line that is tangent to both wheels of the bicycle in the unfolded state. A transverse horizontal direction Y is defined as a direction orthogonal to the longitudinal horizontal direction and parallel to the axes of the wheels in the unfolded state. The vertical direction Z is then the direction perpendicular to both the longitudinal and the transverse horizontal directions.

An embodiment of the invention is a folding bicycle 00 having a frame as shown in Fig. 1. The frame includes a front strut 102 and a rear strut 104. The front and rear struts 102, 104 are joined by a central hinge 106, which allows the front and rear struts 102, 04 to rotate relative to each other about a vertical axis. The front and rear struts 102, 104 can rotate between an unfolded position, in which they form a substantially continuous line extending along the length of the bicycle, and a folded position. The frame is shown in its folded position as viewed in a vertical direction in Fig. 2. The central hinge 106 rotates by approximately 180 degrees between the unfolded position and the folded position. In the folded position, the front and rear struts 102, 104 of the frame are substantially parallel and overlap when viewed in the transverse horizontal direction Y.

A front fork 108 is rotatably attached to the front strut 102 of the frame so as to be pivotable about its longitudinal axis. A front wheel 26 is mounted to the bottom of the front fork 108 so as to be rotatable about a front axle parallel to the transverse horizontal direction Y in the unfolded state.

A handle section is mounted to the top of the front fork 108 via a front hinge 124. The handle section consists of a shaft 120 and handle bars 122 fixed perpendicular to the shaft 120. The front hinge 124 allows the handle section to rotate by roughly 180 degrees relative to the front fork 108, about an approximately horizontal axis. The axis of the front hinge may also be aligned at an angle between the longitudinal horizontal direction X and the vertical direction Z. In an unfolded state, the shaft 120 and the front fork 108 form a substantially continuous straight line in a substantially vertical direction and the handle bars 122 extend in a horizontal direction. In a folded state, both the shaft 120 and the handle bars 122 extend in a slanted longitudinal direction at an angle between the longitudinal horizontal direction X and the vertical direction Z.

Seat stays 110 are fixed to the rear strut 104 of the frame. A rear wheel 128 is mounted to the bottom end of the seat stays 110 so as to be rotatable about a transverse horizontal axis.

When the frame of the bicycle 100 is folded about the central hinge 106, the front and rear wheels 126, 128 approach each other until they are mounted side-by-side in parallel. In this position, one of the left and right sides of the front fork 108 is adjacent to the same side of the seat stays 110 (see Fig. 2). The present embodiment provides a latching mechanism 130 that forms an interlocking engagement between the front fork 108 and seat stays 110 in this state so that the frame is held in the folded state. Views of the latching mechanism 130 are shown in Figs. 3, 4, 5 and 6.

The latching mechanism 130 includes a clip 202 that is fixed to a drop out 114 attached to one side of the seat stays 110. A drop out 114 is attached to each side of the seat stays 110 and a rear axle is mounted between the two drop outs 114. The clip 202 constitutes one example of a latch member 200. The clip 202 used in this embodiment is shown in more detail in Fig. 7. The clip 202 has a recess 204 forming an opening 206 facing towards the rear of the bicycle 100. The clip 202 is formed from a resilient plastics material in this embodiment, so the recess can be deformed elastically.

The recess 204 narrows gradually from the opening 206 to an accommodating portion 214, which is wider than the narrowest part of the recess 204 and is roughly circular in shape.

The clip 202 is attached to the drop out 114 by two bolts in this embodiment. An upper bolt passes through a circular hole 212 in the clip 202 and through an elongated hole in the drop out 114. A lower bolt passes through an elongated hole 208 in the clip 202 and through a circular hole in the drop out 114. The elongated holes in the drop out 114 and the clip 202 extend in the longitudinal horizontal direction X. The two bolts are secured by nuts.

The elongated holes allow the horizontal position of the clip 202 relative to the frame to be adjusted. This allows compensation for manufacturing tolerances when the bicycle 100 is first assembled. Once the bolts have been tightened, the clip 202 is fixed securely to the drop out 114, which in turn is fixed to the seat stays 110 by welding for example.

The latching mechanism 130 also includes a ball stud 302 that is fixed to a tab 112 attached to the side of the front fork 108 that is brought adjacent to the clip 202 when the frame is folded. In the embodiment shown in Figs. 3 to 6, this is the left hand side of the front fork 108 in the unfolded state. The tab 112 may be welded to the front fork The ball stud 302 is shown in more detail in Fig. 9. A threaded tail 306 of the ball stud 302 passes through an elongated hole formed in the tab 1 12. The ball stud 302 is fixed to the tab 1 12 by cooperation between a nut 304 threaded onto the tail 306 on the opposite side of the tab 112 to the head 312 of the ball stud 302 and a flange 308 of the ball stud 302. The flange 308 is disposed at the top of the tail 306 and is on the same side of the tab 112 as the head 312.

The ball stud 302 extends in a horizontal direction parallel to the front axle, with the head 312 of the ball stud 302 facing away from the front fork 108 and wheel 126. The elongated hole in the tab 1 12 is oriented substantially in the vertical direction Z. The elongated hole allows the vertical position of the ball stud 302 to be adjusted during assembly of the bicycle 100 to compensate for manufacturing tolerances. Once the nut 304 has been tightened, the ball stud 302 is fixed securely to the frame via the tab 1 12.

At the top of the head 312 of the ball stud 302, i.e. at the end of the ball stud 302 furthest from the tail 306, a Hex key slot 314 is formed. This allows the ball stud 302 to be rotated relative to the nut 304 so as to fix the ball stud 302 to the tab 112 securely.

The recess of the clip 202 is a force fit to the neck 310 of the ball stud 302 extending between the head 312 and the flange 308. The latch mechanism 130 is designed to operate as follows.

Starting with the bicycle 00 in the unfolded state, the user rotates the front strut 102 towards the rear strut 104 about the central hinge 106. The user rotates the front strut 102 until one side of the front fork 108 reaches a position adjacent to the same side of the seat stays 1 10. The ball stud 302 is mounted to the side of the front fork 108 adjacent to the seat stays 1 10 in the folded state and the clip 202 is mounted to the same side of the seat stays 1 10. Hence, in the folded state the ball stud 302 and clip 202 are adjacent.

With the handle bars 122 in a straight-ahead position perpendicular to the frame, the ball stud 302 is also perpendicular to the frame. In this position, as the front fork 108 is brought towards the seat stays 1 10 in the folding process, the head 312 of the ball stud 302 abuts the side face of the clip 202. The head 312 of the ball stud 302 is too wide to fit into the recess 204 of the clip 202.

In order to engage the ball stud 302 with the clip 202, the user first rotates the handle bars 122 so that the head 312 of the ball stud 302 turns towards the rearward longitudinal direction, i.e. away from the front strut 102. The front strut 102 is then rotated further towards the rear strut 104, which is possible because the head 312 of the ball stud 302 passes the rear end of the clip 202, adjacent to the opening 206 of the recess 204. With the ball stud 302 crossing the opening 206 in this way, the user then rotates the handle bars 122 back towards the straight-ahead position. This rotation forces the neck 310 of the ball stud 302 into the opening 206 of the recess 204.

Since the neck 310 of the ball stud 302 is wider than the narrowest part of the recess 204, the clip 202 deforms elastically to accommodate the neck 310. Once the neck 310 of the ball stud 302 has passed the narrowest part of the recess 204, it enters the accommodating portion 214. The accommodating portion 214 is wide enough to accommodate the neck 310. Hence, the clip 202 returns to its original shape and the neck 310 is prevented from leaving the accommodating portion 214 because the narrowest part of the recess 204 is disposed between the neck 310 and the opening 206. The ball stud 302 is thus held in the recess 204 by the resilience of the clip 202 against deformation.

On the side of the clip 202 facing the seat stays 110 and wheel 128, i.e. the side facing away from the front fork 08 in the folded position, a cup-shaped concave portion 210 is formed. The head 312 of the ball stud 302 fits into this concave portion 210 to provide a more stable engagement between the clip 202 and the ball stud 302.

Following the above operation, the bicycle frame is held in the folded position by the interlocking engagement between the ball stud 302 and the clip 202. In order to release the frame from the folded state, the handle bars 122 are simply rotated in the direction away from the seat stays 1 10, so that the ball stud 302 rotates towards the back of the bicycle 100. This rotation removes the neck 310 of the ball stud 302 from the recess 204 of the clip 202 so that the front strut 102 can be rotated back to the unfolded position. Since the handle bars 122 are used to rotate the ball stud 302 into the clip 202 and subsequently remove it in this embodiment, the force applied to the ball stud 302 by the user is increased by the length of the handle bars 122. This means that a relatively small force applied by the user translates into a large force on the ball stud 302. Hence, a strong force fit and holding force can be provided between the clip 202 and the ball stud 302 without requiring much strength on the part of the user to clip and unclip the frame in the folded position.

There are many possible modifications of the above embodiment that fall within the scope of the present invention. For example, although the opening 206 of the recess 204 of the clip 202 has been described as facing towards the rear of the bicycle 100, it will be appreciated that it may be provided facing towards the front. In this case, the rotations of the handle bars 122 to fit and release the ball stud 302 to and from the clip 202 described above are simply reversed.

In addition, while the clip 202 described above is mounted to the drop out 114 by an upper elongated hole in the drop out 114 and a lower elongated hole in the clip 202, this is not necessarily the case. Each elongated hole may be provided in either or both of the clip 202 and the drop out 114. For example, an alternative embodiment of the clip is shown in Fig. 8. This clip has two elongated holes 208, which means that no elongated holes would be required in the drop out 114 to provide adjustment of the mounting position of the clip. Only one elongated hole or no elongated holes may be provided if adjustment of the clip 202 is not required.

Similarly, the elongated hole by which the ball stud 302 is fixed to the tab 112 may be replaced by a circular hole. Any fixing method may be used to attach the clip 202 to the seat stays 110 and to attach the ball stud 302 to the front fork 108.

The clip 202 and the ball stud 302 may also be mounted at any positions on the frame provided that when the frame is folded the clip 202 and ball stud 302 can be brought into engagement with each other. The clip 202 and the ball stud 302 may be mounted directly to parts of the frame rather than being mounted via the drop out 114 and tab 112 respectively. Although the clip 202 has been described as being mounted on the seat stays 110 and the ball stud 302 has been described as being mounted on the front fork 108, these positions may be reversed. In this case, the rotation of the handle bars 122 described above forces the opening 206 of the recess 204 of the clip 202 onto the neck 310 of the ball stud 302.

Although a clip 202 and a ball stud 302 have been described above, any two

components that cooperate to provide an interlocking engagement can be used instead. For example, the ball stud 302 could be replaced by any protruding member that would fit into the recess 204 of the clip 202 so as to provide a holding force against unfolding of the frame.

In another variant, a hook could be provided on one of the front fork 108 and seat stays 110 and a bar could be provided on the other, so that when the frame is rotated into the folded state the hook hooks onto the bar and prevents the front fork 108 and seat stays 110 from being separated again.

In another alternative embodiment, one part of the latching mechanism 30 is formed by part of the frame itself and the other part of the latching mechanism 130 is arranged to form an interlocking engagement with the frame. For example, a clip could be attached to one of the front fork 108 and seat stays 110, the clip being shaped to fit around one side of the other of the front fork 108 and seat stays 110. By rotating the handle bars 122 as described above in the folded state, the clip could be clipped onto the side of the other of the front fork 108 and seat stays 110 so as to prevent the front fork 108 and seat stays 110 from being separated. The clip could be a force fit to the other of the front fork 108 and seat stays 110 in the same way as the clip 202 and ball stud 302.

The foregoing description has been given by way of example only and it will be appreciated by a person skilled in the art that modifications can be made without departing from the scope of the present invention.

Claims

1. A folding bicycle comprising:

a first frame section;

a second frame section movably mounted to the first frame section so that the first and second frame sections may be moved relative to each other from an unfolded position to a folded position; and

a latching mechanism having a latch member attached to one of the first frame section and the second frame section;

wherein the latch member is adapted to form an interlocking engagement with an engaging part of the other of the first frame section and the second frame section when the first and second frame sections are in the folded state, so as to hold the first and second frame sections in the folded state;

wherein the first frame section comprises a front strut movably mounted to the second frame section and a front fork rotatably mounted to the front strut; and

wherein the latch member is adapted to form an interlocking engagement with the engaging part in response to rotation of the front fork relative to the front strut when the first and second frame sections are in the folded state.

2. A folding bicycle according to claim 1 , wherein one of the latch member and the engaging part is mounted on the front fork.

3. A folding bicycle according to claim 2, wherein the front fork has an axle mounting at a lower end thereof, and the one of the latch member and the engaging part is mounted adjacent the lower end of the front fork.

4. A folding bicycle according to claim 2 or claim 3, further comprising a tab fixed to the front fork, wherein the one of the latch member and the engaging part is mounted on the tab.

5. A folding bicycle according to any of claims 1 to 4, further comprising a handle section including a handle shaft and handle bars mounted to an upper end of the handle shaft so as to be substantially perpendicular to the handle shaft, wherein a lower end of the handle shaft is mounted to an upper end of the front fork.

6. A folding bicycle according to claim 5, wherein the lower end of the handle shaft is rotatably mounted to the upper end of the front fork via a front hinge, so that the handle shaft and the front fork can be rotated relative to each other from an unfolded state to a folded state.

7. A folding bicycle according to claim 6, wherein when the handle shaft and the front fork are in the unfolded state the lower end of the handle shaft is below its upper end, and when the handle shaft and the front fork are in the folded state the upper end of the handle shaft is below its lower end, using a direction from a lower end to the upper end of the front fork as a reference upwards direction.

8. A folding bicycle according to any of claims 1 to 7, wherein the second frame section comprises a rear strut movably mounted to the first frame section and seat stays fixed to the rear strut.

9. A folding bicycle according to claim 8, wherein the seat stays have a drop out at a lower end thereof, and one of the latch member and the engaging part is mounted on the drop out.

10. A folding bicycle according to any one of claims 1 to 9, wherein the second frame section is rotatably mounted to the first frame section.

11. A folding bicycle according to claim 10, wherein:

a rear end of the first frame section is mounted to a front end of the second frame section, and

when the first and second frame sections are in the unfolded state the rear end of the first frame section is rearward of its front end, and when the first and second frame sections are in the folded state the rear end of the first frame section is forward of its front end, using a direction from a rear end to the front end of the second frame section as a reference forwards direction.

12. A folding bicycle according to claim 10 or claim 11 , wherein the second frame section is mounted to the first frame section by a central hinge allowing rotation of the second frame section relative to the first frame section about an axis.

13. A folding bicycle according to any one of claims 1 to 12, wherein the latch member comprises a clip having a recess adapted to accommodate the engaging part.

14. A folding bicycle according to claim 13, wherein the clip is formed from a resilient material and the engaging part is a force fit to the recess.

15. A folding bicycle according to claim 13 or claim 4, wherein the recess has an opening facing towards the rear of the bicycle when the first frame section and the second frame section are in the unfolded state.

16. A folding bicycle according to any of claims 13 to 15, wherein the engaging part comprises a stud.

17. A folding bicycle according to claim 16, wherein the stud is mounted to the other of the first frame section and the second frame section by at least one threaded shaft and a screw drive socket is formed in a head of the stud.

18. A folding bicycle according to claim 16 or claim 17, wherein the stud is a ball stud and the recess is adapted to accommodate a neck of the ball stud.

19. A folding bicycle according to claim 18, wherein a cup-shaped concave portion is formed in the clip, the concave portion being arranged to accommodate part of the head of the ball stud when the neck of the ball stud is accommodated in the recess.

20. A folding bicycle according to any of claims 1 to 19, wherein the latch member is adjustably mounted to the one of the first frame section and the second frame section.

21. A folding bicycle according to claim 20, wherein the latch member is attached to the one of the first frame section and the second frame section by at least one bolt passing through a hole in the latch member and a corresponding hole in the one of the first frame section and the second frame section, and at least one of the holes is elongated so as to allow the attachment position of the latch member to be adjusted.

22. A folding bicycle according to any of claims 1 to 21 , wherein the engaging part is adjustably mounted to a main part of the other of the first frame section and the second frame section.

23. A folding bicycle according to claim 22, wherein the engaging part is attached to the main part by a threaded shaft passing through a hole in the main part, and the hole is elongated so as to allow the attachment position of the engaging part to be adjusted.

24. A method of folding and securing the folding bicycle according to claim 1 , the method comprising:

moving the first frame section from the unfolded position to the folded position relative to the second frame section; and

rotating the front fork relative to the front strut so as to bring the latch member into interlocking engagement with the engaging part, thereby holding the first and second frame sections in the folded position.

25. A method according to claim 24, wherein the rotating step is performed by rotating handle bars of the folding bicycle relative to the front strut.

26. A method according to claim 24 or claim 25, further comprising an initial step of rotating the front fork to a first orientation relative to the front strut, wherein when the first and second frame sections are in the folded position and the front fork is in the first orientation the latch member does not engage with the engaging part.