WO1999008924A1

WO1999008924A1 - A lock unit, in particular for bicycles

Info

Publication number: WO1999008924A1
Application number: PCT/DK1998/000354
Authority: WO
Inventors: Lars Killmann Petersen
Original assignee: Lars Killmann Petersen
Priority date: 1997-08-15
Filing date: 1998-08-14
Publication date: 1999-02-25
Also published as: AU8623598A

Abstract

Wireless, remote controlled locking systems are already known from automobiles, in which a receiver unit can receive an electrically coded signal from a remote control unit, whereby various electrically powered locks may be actuated for locking and unlocking. With the invention it is realized that a similar technique can be advantageously used in connection with single locks on bicycles, when the lock housing has a built-in battery for voltage and current supply of a signal receiver unit (28) and an actuation unit (24, 22) for releasing a stop member (12) for a spring loaded locking bolt (6), which has been brought manually into its locking position against the action of the spring.

Description

A LOCK UNIT, IN PARTICULAR FOR BICYCLES

The present invention relates to a lock unit, in particular a bicycle lock. Traditionally, bicycle locks are manually actuated, while from automobiles it is well known to make use of motor driven locks in central locking systems, even with both key operation and remote control. In automobiles there is plenty of battery power at disposal for the purpose, and for the users it is highly convenient to make use of these systems with more locks. Corresponding advantages, of course, will not be achievable in connection with the single bicycle locks, but nevertheless it has been sporadically proposed - see EP-A- 0,594,954 - to use a motor driven, remote controlled lock also for bicycles, although in connection with an untradi- tional crank or handlebar lock. Such a lock, then, should only have a built-in battery with good capacity.

The present invention is based on the consideration that in connection with more traditional bicycle locks of the type having a manually operated, spring loaded locking bolt, it will not be particularly attractive to modify such locks for motor actuation, while on the other side it will be attractive to provide for an electrically controlled unlocking of the manually closed locks. In practice, this can be arranged by incorporation of a simple actuator for releasing the normally used locking pawl for the lock bolt. Since this pawl, in the lock position, is in pressure engagement with the spring loaded lock bolt, it will require a certain force to release the pawl, but it has been found that in practice this is nevertheless possible with a low power consumption, such that a built-in battery may have a reasonably long lifetime. With the use of the electrically controlled actuation of the unlocking, the locks may be produced so as to be mechanically exactly alike, as the need for coding the locks can be satisfied by the involved electronics. Thus, the locks should have neither keying means nor mechanical coding systems, whereby these potential objects of attack for unauthorized unlocking of the locks will disappear entirely. While the mechanism effecting the locking of the lock can be designed in a very robust manner, typically by way of a spring loaded, heavy lock pawl, the electrically controlled releaser device should not be correspondingly heavy, as it will have no other purpose than to bring the lock pawl out of its active position. The lock will still be purely mechanically self arresting, without any actuation other than the manual tightening of the lock bolt. It is important that the lock pawl should not be operated in any other way than by a very brief retraction, as the lock bolt itself will immediately thereafter block the pawl against a renewed locking engagement with the bolt . Hereby it is sufficient to actuate the releasing device with the re- quired force during a very short time, e.g. 1/4-1/2 second by each unlocking, whereby the said long duration of the battery can be ensured. Besides, it will also be possible to use an electrically very underdimensioned actuator, as the latter will resist a heavy overload during the brief operations pe- riods .

On this background, the invention is defined as specified in claim 1.

With the invention it has been found attractive to use as an actuator a small electrical motor of fastrunning type which, by means of a fine thread directly on the motor shaft, co-operates with a portion of a floatingly held lock pawl in such a manner that this pawl, in the locked position, is forced against the thread by the pressure exerted by the shoulder portion of the lock bolt, whereby an actuation of the motor will provoke a 'screwing out¹ of the pawl. The said pressure on the pawl will cease immediately after such a release, viz. as soon as the bolt spring starts to move the bolt towards its open position, and thereby the pawl will be free to disengage itself from the actuator thread, preferably by the action of a weak spring, which may additionally seek to pull the pawl into its locking position. In connection with a renewed locking the pawl will then snap into its locking position, and at the same time the thread engaging por- tion thereof, now free of the thread, will be moved to its starting position just outside the thread. The tightened lock bolt, in response to being released, will move a little rear- wardly by the action of the strong spring and thus again force the said engaging portion of the lock pawl against the thread, ready for a following unlocking. It will be appreciated that the motor should not be controlled to stop at any particular stop position, as the pawl will automatically leave its engagement with the thread as soon as the pawl re- leases the lock bolt. The said small motors, working with a speed of some 15.000 rpm, are very cheap, and if they are adapted to an operation voltage of 4.5 V, for example, they may well be actuated with the double of that voltage during the actual brief periods, whereby in connection with the fine thread they may provide a strong release impulse with a high degree of operational security.

As mentioned, it is possible to entirely avoid potential areas of attack in connection with keying or coding systems, but since the lock is still to be locked manually there will still be an area of attack for attempted unauthorized unlocking, viz. the projecting handle knob on the lock bolt, which can tempt to acts of "return knocking" the locked bolt. With the invention, however, it is possible to rely on such a safe unlocking operation of the lock that there will not be or arise any need for the user to help the bolt with its returning from the locking position, and on that background it is a preferred measure according to the invention that the lock housing be designed with a V:igid shield positioned right in front of the handle knob in the locked position of the lock bolt, thereby preventing the use of exterior force in the opening direction of th handle knob.

An embodiment of a lock according to the invention is shown schematically on the Figure, which shows an open housing part 2, preferably made of cast aluminium and adapted to be closed by a cover plate. The housing is provided with a circular channel 4 for a part circular lock bolt 6 having a projecting handle knob 8 and co-operating with a tension spring 10 which, in conventional manner, is tightened when the bolt is swung down for locking the lock.

For arresting the bolt 6 there is provided a pawl body 12, which co-operates with a shoulder face 14 of a recess in the bolt and with a tension spring 16 seeking to pull the associated end of the pawl into this recess, while it also pulls the pawl towards the right. The pawl is arranged in a pivotable and cross displaceable manner about a pin 18 such that the bolt, upon having established the locking engage- ment, will force the pawl 12 towards the left by the spring 10 overcoming the action of the spring 16, until the pawl is stopped by the pin 18.

The opposite end of the pawl is shaped as a flat wedge portion 20 which is laterally projecting towards a worm por- tion 22 on the shaft of a motor 24. When the pawl 12 is pulled into its locking position against the shoulder face 14, the pawl will be pulled farthest possible towards the right by the action of the spring 16, and the wedge end 20 will be entirely out of engagement with the worm 24, such that the pawl is free to carry out the required pivoting into its locking engagement. When thereafter the spring 10, via the shoulder face 14, pushes the pawl towards the left, the latter will be stopped by the pin 18 in an end position in which the wedge end 20 is brought into engagement with the upper end portion of the worm 22.

For unlocking the lock it is sufficient to actuate the motor 24 with such a direction of rotation that the worm screws downwardly. This will force the pawl to pivot about the pin 18 such that its locking end is swung up from the shoulder face 14. As soon as this release happens, the spring 16 pulls the wedge edge 20 free of the worm 22, and the bolt 6 jumps back to the open position of the lock.

The motor 24 should be actuated only very briefly for effecting an unlocking, i.e. the lifetime of a built-in battery can be expected to be long. It should be mentioned that suitable mini-motors 24 are obtainable at prizes with which not even simple attraction coil systems can compete. 28 designates a box with electronics, having a window portion for IR or corresponding communication with an electronic "key" and including a circuit for decoding an associated keying code for the actuation of the motor 24. Cer- tainly, the lock may thus be releasable by remote control, but the remoteness of the control in connection with bicycle locks will not, per se, be particularly qualified. The user may well manage to hold an actuator unit tightly against the lock housing, and it will be possible to thereby operate with an inductive transfer of both code signals and power supply. If so, the built-in battery 26 can be avoided and replaced by an optionally rechargeable battery in the actuator unit.

The flat wedge 20 on the lock pawl 12 may consist of a hard flat wedge for engagement with the worm thread 22, but preferably there is used a V-shaped engagement portion of an only semihard material, e.g. Nylon, which may have a height dimension bridging several thread crests, i.e. without forming a sharp flat edge. When such a portion, even with entirely planar inner surfaces, is forced against a fine thread, a driving engagement will be obtained that is fully sufficient for the transfer of the required retraction force to the pawl 12.

In principle, the worm thread 22 may coact with a nut portion at the end 20 of the pawl 12, whereby the latter is controllable in a more rigid manner. The motor 24 is a reversible DC motor which can easily be brought to rotate in the reverse direction for returning such a nut into its starting position.

It should be noted that the pawl may well be fully float- ingly mounted, without the use of the pin 18, when the pawl body and its associated mounting recess in the lock housing 2 are shaped for that purpose .

As indicated, the lock housing may be provided with a lower widening 30 just below the handle knob 8 in the locking position thereof, whereby it is made difficult to seek to break up the lock by beating impacts on the handle knob, which is also, itself, shaped accordingly.

Claims

C L A I M S :

1. A lock unit, in particular a bicycle lock, characterized by the combination of

- having a lock bolt which, by means of a handle and against a spring bias, is manually movable from an open position to a locking position, in which it is arrested by means of a releasable pawl; - having an electrically driven actuator mechanism which is preferably of a coded, remote control - lable type; and

- said actuator mechanism being a release mechanism, which is operative solely for actuation of said pawl in order to release the lock bolt for the returning thereof to its open position.

2. A lock unit according to claim 1, characterized in that the release mechanism comprises an actuator unit of remote controllable type, the lock comprising the required electronics and voltage supply for being able to cooperate with an electrically coded remote control unit in a wireless manner .

3. A lock unit according to claim 2, characterized in that the electrical motor is connected to a voltage source through a control unit which, when actuated, effects a connection of the motor through a period of a maximum of the magnitude one second, and that the voltage source is hereby caused to supply to the motor a voltage which is noticeably higher than the nominal operation voltage of the motor, preferably about twice thereof.

4. A lock unit according to claim 2, characterized in that the portion of the lock pawl cooperating with the thread of the motor spindle consists of a hard-resilient material such as Nylon 6/6 which, in the arresting position of the lock pawl, is held laterally forced against the thread of the spindle, this thread being configured with a sharp angled crest profile, preferably as a fine thread with a small thread pitch.

5. A lock unit according to claim 4, characterized in that the engagement portion of the lock pawl is a bifurcated portion which, when forced against the thread of the motor spindle, is forced thereagainst primarily at mutually separated areas of the thread.

6. A lock unit according to claim 4, characterized in that the lock pawl is floatingly mounted in such a manner that it is displaceable between a free position, in which it is influenced by a light spring bias opposite to the opera- tive pawl end so as to be retracted from engagement with the said thread at a control end portion opposite to the operative pawl end, while the latter is biased to pivot against the lock bolt in a released position, in which the said control end portion is located next to the thread, without en- gaging it, and an arresting position in which the operative pawl end, here engaging a shoulder face of the biased lock bolt, is forced rearwardly by this engagement, for pressing the control end portion against the thread.

7. A lock unit according to claim 6, characterized in that the lock pawl is mounted about a cross pin so as to be displaceable to a limited extent between the said extreme positions .

8. A lock unit according to claim 1, characterized in that the lock housing is shaped with shield means which in the locking position of the lock bolt shields the projecting handle knob of the bolt from being subjected to external forces in the direction away from the locking position.