GB2593430A - A lock for a cycle - Google Patents

Abstract

A lock for a cycle comprisesing a main body 8 and two jaws 16, 18 which move relative to the body 8 of the lock from an unlocked position to a locked position, the jaws 16, 18 moving into the locking position in such a manner that the ends 120, 122 of the jaws move towards one another, the jaws 16, 18 acting to prevent the spokes of a cycle wheel from passing through the lock. A detent (34, figure 2) secures the jaws 16, 18 in an unlocked position and a pawl 90 secures them when locked. The lock may be secured to the front or rear of a cycle.

Description

A Lock for a Cycle The invention relates to a lock for a spoked wheel of a cycle, such as a bicycle, tricycle, motorcycle or moped.

A known bicycle lock, commonly known as a "horseshoe" lock, locks the bicycle by feeding a bar through the spoked rear wheel and locking it in place so that the wheel cannot rotate. The bar is mounted in a casing which is mounted to the rear stays of the frame of the bicycle.

The horseshoe lock has a single curved bar, which is pushed out of its casing by the user from one side of the wheel, through the spokes, in an arc to take up its locking position by locating in a recess in the lock casing on the other side. The bar is locked in position by a pin which enters a groove in the bar. To unlock the horseshoe lock, the pin is lifted out of the groove by means of turning of the key or by an electro-mechanical mechanism, to release the locking bar, and the locking bar is then retracted back into the casing by a tension coil spring.

There are several issues with the known horseshoe lock. The coil spring is flimsy and may break thus releasing the bar into the path of the spokes causing the bike to stop suddenly with the potential for the rider to fall off or have an accident. The bar can be forced by rotation from its locked position as the design does not allow for much engagement with the part of the casing that receives the end of the bar. The smooth running of the curved bar when retracted under the pull of the coil spring can be affected or impeded by a build up of detritus over time. The components used mean that the size, in particular the thickness, of the lock is greater than it could otherwise be.

According to one aspect of the invention, there is provided a lock for a cycle, the lock comprising a main body and two jaws which move relative to the body of the lock from an unlocked position to a locked position, the jaws moving into the locking position in such a manner that the ends of the jaws move towards one another, the jaws acting to prevent the spokes of a cycle wheel from passing through the lock.

In this way, each jaw has less far to travel, so a long coil tension spring is not required. The lock is more robust, as each jaw cantilevers out of the main body for a shorter distance than in the known horseshoe lock. This also means there is less area for the build up of detritus.

Preferably, the ends of the jaws overlap, for example, one being above the other. This provides additional security. Preferably further, part of each jaw lies in the path of a spoke in the locking position. In this way, each jaw locks the wheel from rotating and hence locks the cycle. Even if one jaw should be moved out of the way of the spokes, the other will still prevent them from turning and hence lock the cycle.

The lock may be constructed in any suitable way, but in a preferred embodiment each jaw is mounted on the end of a pivotally mounted lever. The levers are preferably interconnected such that movement of one lever to close the jaw thereon results in movement of the other lever to close the other jaw. An extension of one lever may be arranged to abut an extension of the other lever, so that when said one lever is moved to move the jaw thereon into the locking position, the extension thereon abuts the extension on the other lever to move the other lever into the locking position.

The jaws may be held in the unlocked position by a detent. The jaws may be biased into the unlocked position by biasing means. Preferably the lock includes both the biasing means and the detent. This reduces the danger of one of the parts failing and one or both jaws coming accidentally into the locking position. The biasing means may take any suitable form and may comprise a torsion spring. Torsion springs are less liable to failure and have a longer operational life than the long tension coil springs used in the known horseshoe lock.

The jaws may be held in the locked position by locking means. The locking means may take any suitable form and may comprise a locking pawl.

In the lock, the jaws may be sandwiched between two plates. This provides a light, strong casing and protection for the jaws. The top and/or sides of one plate may be folded back to cover the gap between the plates. This protects against water ingress, and also against foreign matter entering to interfere with the mechanism, and against tools being inserted for the purposes of theft or vandalism.

According to another aspect of the invention, there is provided the combination of a cycle and a lock, the lock being mounted on the cycle.

In the combination, the lock may be mounted to the front of the front fork of the frame. Alternatively, the lock may be mounted to the rear of the seat stays of the frame.

An embodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which: Fig 1 is a perspective view of the lock of the embodiment of the invention on the front of the front fork of a bicycle; Fig 2 is a perspective view of the lock in the unlocked position with the front plate removed; Fig 3 is a rear view of the lock with the actuator casing removed; Fig 4 is a front view of the lock on the front fork of a bicycle with the front plate removed; and, Fig 6 is a rear view of the lock.

The lock 10 of the embodiment of the invention comprises a front plate 12 and a rear plate 14 comprising the main body 8 of the lock, and two jaws 16, 18 carried by two levers 20, 22.

The first lever 20 has an elongate part 24 which carries the jaw 16 at one end and is connected to an enlarged part 26 at the other end. The enlarged part 26 defines an aperture 28 to receive a short cylindrical sleeve 30 about which the lever 20 is arranged to pivot. The enlarged part 26 further includes a driven part 32 which extends inwardly in a similar direction to the jaw 16 and defines a generally downwardly facing abutment surface 36. The enlarged part 26 also includes a step 34 on the outside of the part defining the aperture 28. The rear plate 14 defines a part circular slot 38, see Fig 3, which is concentric with the axis of pivoting of the first lever 20 at the aperture 28. A pin 40 fast with the rear surface of the first lever 20 is received in the slot 38 and a torsion spring 42 acts on the pin 40. The torsion spring 42 is wound around the short cylindrical sleeve 30 and one end of the spring 42 engages the pin 40, while the other end is anchored by being bent over the edge of the rear plate 14 (Fig 3).

The second lever 22 is similar to the first lever 20 in including an elongate part 50 and an enlarged part 52 which defines an aperture 54 mounting a short cylindrical sleeve 56 about which the second lever 22 is arranged to pivot. The second lever 22 defines a driving part 58 which extends inwardly in a similar direction to the jaw 18 and defines a generally upwardly facing abutment surface 60. Above the pivot aperture 54 is a foot shaped projection 62. On the outside of the elongate part 50 is a generally triangular protrusion 64.

The front and rear plates 12, 14 define two legs 70, 72 with a downwardly facing, parallel sided cut out 74 between them. The pivot apertures 28, 54 are approximately in line with the parallel sides 76, 78 of the cut out 74, and at the same height.

A casing 80 is attached to the back of the rear plate 14. Inside the casing is an actuator, such as a motor, such as a worm drive motor (not shown). The casing 80 also mounts a detent 82 in the form of a pivot arm 84 with an angled face 86 to engage the enlarged part 26 of the first lever 20. The pivot arm 84 is biased by a torsion spring 88 within the casing 80 into contact with the first lever 20.

A locking pawl 90 is carried by the back plate 14 and its pivoting movement is controlled by the motor in the casing 80. The acting surface 92 of the pawl 90 is arranged to contact the heel 68 of the foot shaped projection 62 of the second leg 22.

As seen in Figs 1 and 5, the top edge of the front plate 12 is bent backwards to form a tab 96 which covers from above the gap between the plates 12, 14 to prevent water or dirt getting in and reduce the risk of interference by thieves or vandals. In another embodiment, the sides could be similarly protected.

The plates 12, 14 are held together by rivets 104, 106, 112, 114, see Fig 1. There are apertures 100, 102 in the front and rear plates 12, 14 aligned with the pivot apertures 28, 54 in the levers 20, 22 and two rivets 104, 106 are located through these apertures 28, 54, 100, 102. Using the pivot apertures 28, 54 for the rivets 104, 106 rather than having separate apertures improves overall strength and reduces the number of manufacturing operations. There are two further apertures 108, 110 in the plates 12, 14 below the jaws 16, 18 at the entrance to the cut out 74, and those apertures 108, 110 receive rivets 112, 114.

In use, the lock 10 is fixedly mounted to the front of the front forks of a bicycle or tricycle so that the tyre and rim of the spoked wheel of the cycle pass through the cut out 70 with the jaws 16, 18 lined up with with the spokes of the wheel, the jaws being aligned perpendicular to the plane of the wheel so that they are below the rim of the wheel and able to pass through the spokes. In the unlocked position shown in Fig 2, the legs 20, 22 are biased by the torsion spring 42 so that the jaws 16, 18 are apart and in fact lie behind the legs 70, 72 so that the jaws 16, 18 do not project beyond the legs 70, 72 into the cut out 74. Thus the torsion spring 42 acts between the casing 80 and the pin 40 of the first lever 20. This biases the first lever 20 clockwise as seen in Fig 2.

The abutment surface 36 of the first lever 20 engages the abutment surface 60 of the second lever 22 so that the second lever 22 is also pivoted. In this position of the arms, the angled face 86 of the detent 82 lies behind the step 34 of the enlarged part 26 of the first lever 20 in order to retain the first lever 20 in position. The second lever 22 will be held by the first lever 20 through the abutment surfaces 36, 60.

To lock the lock 10, the user presses the triangular protrusion 64 of the second lever 22, which protrudes beyond the front and back plates 12, 14. This will move the second lever 22 and hence through the abutment surfaces 36, 60 the first lever 20 against the bias of the torsion spring 42. The jaws 16, 18 will then approach each other until they nearly touch. At this point, the locking pawl 90 will be rotated so that the acting surface 92 of the pawl 90 contacts the heel 68 of the foot shaped projection 62 of the second leg 22 to hold the second leg 22 in position. Through the abutment surfaces 36, 60 the first leg 20 will also be locked.

It will be seen that in the locked position, the ends 120, 122 of the jaws 16, 18 overlap, that is to say, the ends 120, 122 are mutually angled to lie one above the other in the locked position. In this way, if one should somehow fail or be bent out of position, the other will still be in the way of the spokes.

To unlock the lock, a signal is sent to the actuator to rotate the locking pawl 90, at which point the second lever 22 will be released and the two levers 22, 20 will pivot under the action of the torsion spring 42 so that the jaws 16, 18 move apart out of the way of the spokes of the wheel to their rest, unlocked position as shown in Fig 2.

It is thus seen that, in the lock of the embodiment, there are two mechanisms to hold the lock open, namely the bias of the torsion spring 42, and the action of the detent 82. Thus the risk of the lock 10 closing by accident and hence stopping a wheel is very small. For this reason, the lock is suitable for use not only on the rear seat stays of a cycle but also on the front fork of a cycle. Accidental stopping of the front wheel is much more serious as the rider can lose control of the bicycle or go over the handlebars, whereas accidental stopping of the rear wheel may only lead to a controllable skid.

The lock 10 is very slim, as major components, the front and rear plates 12, 14, and the levers 20, 22 are made from flat metal plate. Significantly, the lock 10 is much slimmer than the known horseshoe lock making it suitable for applications where space is limited. The front and rear plates 12, 14, and the levers 20,22 may be cut or stamped from steel which would allow for heat and chemical treatments such as Nitrotec (Registered Trade Mark) surface conversion, to add strength, increase corrosion resistance and reduce friction between mating parts.

to The surfaces may be passivated and a coat of zinc and nickel may be added for corrosion resistance.

The casing 80 may be made of glass fibre filled PBT (polybutylene terephthalate), which is dimensionally stable and strong.

As the jaws 16, 18 and levers 20, 22 move backwards and forwards over a short distance, compared with the movement of the bar in the known horseshoe lock, this tends to move any debris out of the mechanism so that the lock works smoothly and reliably.

Although in this embodiment, the locking pawl 90 is moved by an actuator, it could be moved manually, in another embodiment, to unlock the lock.

If required, the locking pawl 90 could be configured so that when driven by the actuator (or manually) it could act to push against the foot shaped projection 62 so as to rotate the lever 22 and hence lever 20 into the locked position.

In another embodiment, the jaws could act similarly but with their ends overlapping in two parallel planes to provide greater overlap, if required.

Claims (16)

1. CLAIMS1. A lock for a cycle, the lock comprising a main body and two jaws which move relative to the body of the lock from an unlocked position to a locked position, the jaws moving into the locking position in such a manner that the ends of the jaws move towards one another, the jaws acting to prevent the spokes of a cycle wheel from passing through the lock.
2. 2. A lock as claimed in claim 1, wherein the ends of the jaws overlap.
3. 3. A lock as claimed in any preceding claim, wherein part of each jaw lies in the path of a spoke in the locking position.
4. 4. A lock as claimed in any preceding claim, wherein each jaw is mounted on the end of a pivotally mounted lever.
5. 5. A lock as claimed in claim 4, wherein the levers are interconnected such that movement of one lever to close the jaw thereon results in movement of the other lever to close the other jaw.
6. 6. A lock as claimed in claim 5, wherein an extension of one lever is arranged to abut an extension of the other lever, so that when said one lever is moved to move the jaw thereon into the locking position, the extension thereon abuts the extension on the other lever to move the other lever into the locking position.
7. 7. A lock as claimed in any preceding claim, wherein the jaws are held in the unlocked position by a detent.
8. 8. A lock as claimed in any preceding claim, wherein the jaws are biased into the unlocked position by biasing means.
9. 9. A lock as claimed in claim 8, wherein the biasing means is a torsion spring.
10. 10.A lock as claimed in any preceding claim, wherein the jaws are held in the locked position by locking means.
11. 11.A lock as claimed in claim 10, wherein the locking means is a locking pawl.
12. 12.A lock as claimed in any preceding claim, wherein the jaws are sandwiched between two plates.
13. 13.A lock as claimed in claim 12, wherein the top and/or sides of one plate is folded back to cover the gap between the plates.
14. 14. The combination of a cycle and a lock, the lock being mounted on the cycle.
15. 15. The combination as claimed in claim 14, wherein the lock is mounted to the front of the front fork of the cycle.
16. 16. The combination as claimed in claim 14, wherein the lock is mounted to the rear part of the frame.