WO2004069635A1

WO2004069635A1 - Device for theft prevention

Info

Publication number: WO2004069635A1
Application number: PCT/NL2004/000045
Authority: WO
Inventors: Benjamin Willem Ter Kuile; Ernst Coenen
Original assignee: SPECIAL BRANCH
Current assignee: SPECIAL BRANCH
Priority date: 2003-01-20
Filing date: 2004-01-20
Publication date: 2004-08-19
Anticipated expiration: 2005-07-20
Also published as: NL1022433C2

Abstract

A device for theft prevention, suitable to be used with a bicycle that may optionally be provided with a motor, and that is designed to work together with a crankshaft of the bicycle, comprising a crank to be mounted on the crank- shaft and provided with a pedal, a coupling member to be operated with an external key, having an uncoupled position and a coupled position, where in the uncoupled position the crank is allowed to run clear of the crankshaft, and in the coupled position the crank and the crankshaft are coupled, wherein the coupling member is exclusively and entirely accommodated in a break-proof housing located at an end of the crank opposite the end where the pedal is mounted, with the coupling member being equipped to work together with a standard model crankshaft.

Description

Device for theft prevention

The invention relates to a device for theft prevention, suitable to be used with a bicycle that may optionally be provided with a motor, and that is designed to work together with a crankshaft of the bicycle, comprising a crank to be mounted on the crankshaft and provided with a pedal, a coupling member to be operated with an external key, having an uncoupled position and a coupled position, where in the uncoupled position the crank is allowed to run clear of the crankshaft, and in the coupled position the crank and the crankshaft are coupled so as to be rotatingly fixed to each other .

Such a device is known from the German Utility Model DE-U-29,500,798.2.

A drawback of the device known from this publication is that it cannot be used for existing bicycles since the use of this known device requires the design of the crankshaft of the bicycle and its housing to be modified and adapted to the design of the device. A related problem is that the use for newly to be manufactured bicycles is costly because of the referred-to required structural adaptations to the bicycle. A complicating factor is that, according to the type of bicycle, the crankshaft housings are supplied in various sizes and designs, so that equally many adaptations need to be made to these designs before the device for theft prevention pro- posed in the German Utility Model can be employed.

The object of the invention is to provide a generally usable device for theft prevention that can be employed without structural adaptation of existing, or newly to be manufactured bicycles. In accordance with the invention a device is proposed for this purpose that complies with one or several of the appended claims.

In a first aspect of the invention, the device is characterised in that the coupling member is exclusively and entirely accommodated in a break-proof housing located at an end of the crank opposite the end where the pedal is mounted, with the coupling member being equipped to work together with a standard model crankshaft.

By means of this measure the theft prevention device is easy to implement as a device that may replace a standard crank. Fitting the device according to the invention suffices to convert an existing bicycle or to provide a newly to be manufactured bicycle that meets the requirements of theft prevention as intended with the invention.

The coupling member of the device according to the invention may conveniently be embodied such that the same comprises a first plate that is adjustable between the uncoupled position and the coupled position, being rotatingly fixed with the housing and being provided with means for coupling to or, as the case may be, releasing a base plate that is mounted so as to be rotatingly fixed on the crankshaft.

In this way it is possible for the crank in the uncoupled position to only rotate uselessly, without being able to transmit any drive power to the crankshaft.

This may further be conveniently implemented such that the means of the first plate are pins or projections and that the base plate has recesses for receiving these first pins or projections.

In another aspect of the invention, the device is characterised in that the housing possesses a locking plate facing away from the crankshaft, which when the coupling member is in the uncoupled position, is secured against removal.

This affords the advantage that it is impossible to replace a crank mounted on the bicycle in accordance with the invention with an ordinary crank, because the locking plate blocks the access to the mounting/demounting means of the device.

One thing and another may conveniently be embodied such that the locking plate and the housing possess an inter- mating thread, and that the locking plate at its side facing toward the interior of the housing, and the first plate at its side facing toward the locking plate are provided with coupling means working together that are active in the uncoupled position of the coupling member. It is advantageous that the coupling means are formed by intermating second pins or projections and respective recesses.

It should be noted that mounting or demounting of the device can in fact take place when the coupling means are not active, i.e. when the crank and the crankshaft are in the coupled position.

Hereinafter the invention will be further elucidated with reference to the drawing showing a non-limiting exe - plary embodiment of a device according to the invention.

The drawing shows in:

- Figure 1 an exploded view of a device according to the invention,

- Figure 2 a partly mounted device according to the invention,

- Figs . 3 and 4 a cut-away view of the coupling member forming part of the device according to the invention,

- Figures 5 and 6 a cut-away view of the device according to the invention mounted on a crankshaft, and - Figure 7 an inside of the locking plate of the device according to the invention.

In the figures similar parts are identified by identical reference numbers.

Referring first to Figure 1, a crankshaft housing 1 is shown, with which the person skilled in the art is quite familiar, and accommodated therein a standard model crankshaft 2.

The device according to the invention comprises a crank A provided with a pedal 12, with Figure 1 clearly show- ing that at its end facing away from the pedal 12, the crank possesses a housing 4. This housing 4 is break-proof, which will also be further explained in the description below.

In order to mount the crank on the crankshaft 2, a base plate 5 that can be placed at the inside of the housing, is mounted on the crankshaft 2 by means of a bolt 3. Although in this way the crank as such is indeed mounted, it is able to rotate freely because the coupling between the base plate 5 and the crank or the housing of the crank 4 is not a rotat- ingly fixed coupling. The crank 4 mounted thus with the aid of the base plat 5 is shown in Figure 2.

The coupling member comprises the components that in Figure 1 are identified by reference numbers 6 to 11. These components may be assembled in advance and work together in such a way that with the aid of an external key the crank or the housing 4 and the base plate 5 can be coupled or uncoupled in a manner that will be explained later on.

Figure 1 clearly shows that the coupling member 6,7,8,9,10,11 comprises a first plate 8 which, as will also be explained later on, is adjustable between an uncoupled position and a coupled position, and which is coupled so as to be rotatingly fixed with the housing 4 of the crank. To this end the first plate 8 works together with the first sleeve 7 and the bearing disk 9, which are provided with external key ways that are able to intermate with keys incorporated in the housing 4 of the crank. Rotation of the crank thus also causes rotation of the first plate 8.

As Figure 1 clearly shows, the first plate 8 is pro- vided with means in the form of first pins disposed perpendicularly on the plate 8 at the side of the first sleeve 7, which pins are able to intermate with recesses in the base plate 5.

In order to move the first plate 8 so as to realise the changeover between the uncoupled position and the coupled position, the first plate 8 is mounted on a second sleeve 6, with the second sleeve 6 having an exterior and the first plate 8 having an interior thread, which are able to intermate. The second sleeve 6 further possesses a lock and an end projecting through the centre of the locking plate 10, such that the lock can be operated with a key and the second sleeve can be turned. As a result of said threaded coupling this turning causes the movement of the first plate 8.

The Figures 3 and 5 show the first plate 8 in the uncoupled position wherein the first pins of the first plate 8 are clear of the recesses in the base plate 5. In this way the crank and housing 4 are able to rotate freely around this (stationary) base plate 5, making cycling impossible. The Figures 4 and 6 show the coupling member in the coupled position. Figure 6 clearly shows that the respective first pins of the first plate 8 have been moved to project into the recesses of the base plate 5, so that when the crank and housing 4 rotate, the first plate 8 is rotatingly fixed thereto and - via the said pins - the base plate 5 coupled thereto will rotate also and will make cycling possible.

Referring again to Figures 3 and 5, it is shown that the housing has a locking plate 10 facing away from the crankshaft 2, which when the coupling member 6,7,8,9,10,11 is in the uncoupled position, is secured against removal.

From Figure 5, among others, it is apparent that the locking plate 10 and the housing have an intermating thread and that (see also Figure 7) the locking plate 10, at its side facing toward the interior of the housing, and the first plate 8 at its side facing toward the locking plate 10, are provided with intermating coupling means that are active in the uncoupled position of the coupling member 6,7,8,9,10,11 shown in Figure 5. In this uncoupled position therefore, sec- ond pins mounted on the first plate 8 and oriented toward the locking plate 10, project into recesses of the locking plate 10. These recesses are provided at the inside of the locking plate 10, as shown in Figure 7. Due to this provision the locking plate 10 cannot be unscrewed from the housing and can consequently not be removed. This also renders the bolt 3, with which the crank according to the invention is mounted on the crankshaft 2, inaccessible, such that in the uncoupled position of the coupling member as shown in Figure 5, demounting of the device according to the invention is i possi- ble.

Figure 6, finally, which relates to the device according to the invention while the coupled position between the crank 4 and the crankshaft 2 is in effect, shows that the respective second pins of the first plate 8 no longer project into the recesses of the locking plate 10, such that in this coupled position the locking plate 10 can be removed, making demounting (and also mounting) of the device possible. The above elucidation and the exemplary embodiment employed therein are expressly intended as non-limiting with regard to the protective scope merited by the essence of the invention. The example and the given explanation merely serve for the clarification of any possible ambiguities that may be contained in the appended claims, without in any way limiting these with respect to the protective scope, which is determined by the essence of the invention, in accordance with the subject matter of the appended claims.

Claims

1. A device for theft prevention, suitable to be used with a bicycle that may optionally be provided with a motor, and that is designed to work together with a crankshaft of the bicycle, comprising a crank (4) to be mounted on the crankshaft (2) and provided with a pedal (12), a coupling member to be operated with an external key, having an uncoupled position and a coupled position, where in the uncoupled position the crank (4) is allowed to run clear of the crankshaft (2), and in the coupled position the crank (4) and the crankshaft (2) are coupled so as to be rotatingly fixed to each other, characterised in that the coupling member (6,7,8,9,10,11) is exclusively and entirely accommodated in a break-proof housing (4) located at an end of the crank opposite the end where the pedal (12) is mounted, with the coupling member being equipped to work together with a standard model crankshaft (2) .

2. A device according to claim 1, characterised in that the coupling member (6,7,8,9,10,11) comprises a first plate (8) that is adjustable between the uncoupled position and the coupled position, being rotatingly fixed with the housing (4) and being provided with means for coupling to or, as the case may be, uncoupling a base plate (5) that is mounted so as to be rotatingly fixed on the crankshaft.

3. A device according to claim 2, characterised in that the means of the first plate (8) are pins or projections and that the base plate (5) has recesses for receiving these first pins or projections.

4. A device according to one of the preceding claims, characterised in that the housing possesses a locking plate (10) facing away from the crankshaft (2), which when the coupling member is in the uncoupled position, is secured against removal.

5. A device according to claim 4, characterised in that the locking plate (10) and the housing possess an intermating thread, and that the locking plate (10) at its side facing toward the interior of the housing, and the first plate at its side facing toward the locking plate (10) are provided with coupling means working together that are active in the uncoupled position of the coupling member.

6. A device according to claim 5, characterised in that the coupling means are formed by intermating second pins or projections and respective recesses.

7. A device according to the content of one of the preceding claims, characterised by the essence of the inven- tion as disclosed in the specification and/or the drawings and/or the grant file.