WO2008032038A2

WO2008032038A2 - Electronic securing device

Info

Publication number: WO2008032038A2
Application number: PCT/GB2007/003419
Authority: WO
Inventors: Simon Powell
Original assignee: Pbt (Ip) Limited
Priority date: 2006-09-11
Filing date: 2007-09-11
Publication date: 2008-03-20
Also published as: GB0617827D0; GB0906155D0; GB2455263A; WO2008032038A3

Abstract

A portable electronic securing device comprising a lock body mounting a shackle moveable n locked and unlocked positions, this movement being controlled by an electrically controlled lock release mechanism. The lock release mechanism comprises piezo ceramic actuator device acting on a latch, which is arranged to be received in a recess in the shackle. A buffer mechanism is arranged to be responsive to movement of the shackle and to prevent axial movement of the shackle being transmitted to the piezo ceramic actuator device when excess force is applied to the shackle.

Description

Electronic Securing Device

The present invention relates to an electronic securing device and more particularly a portable electronic securing device.

Portable securing devices in the form of padlocks have been known for a considerable number of years but more recently keyhole-less electronic padlocks have been contemplated and one such device is disclosed in GB-A-2184774. In this prior proposal, a traditional "hoop" style padlock has been utilised and the basic functionality is the same of that as a conventional key/cylinder based padlock. After successful authentication, the user is able to lift the hoop which is free to pivot once unlocked. Locking and unlocking is achieved by means of a solenoid and this necessitates some considerable power which is difficult to supply given the "go-anywhere" nature and long in-service life of such a product.

It is proposed to utilise a piezo ceramic controlled latching mechanism for latching the hoop to the body of the securing device.

Preferably, the piezo ceramic latching device is as described in our co-pending application WO 2004/077473.

In order for the present invention be more readily understood, an embodiment thereof will now be described by way of example with reference to the accompanying drawings in which: -

Fig. 1 shows cross-sectional plan view of a portable securing device according to the present invention; and Fig. 2 shows a cross-sectional side view of the device shown in Fig.1.

The preferred embodiment of the present invention takes the form of an electrically controlled, mechanically latched portable locking device which looks similar to a conventional padlock insofar as it has a main body and a movable shackle which may take the form of a rod, hoop or hasp. The basic functionality is the same as that as a conventional key/cylinder based padlock but the present invention proposes to dispense with a conventional key and keyhole and to utilise a keyhole-less construction.

This basic construction is capable of a number of functional modifications and this should be kept in mind when considering the following description of the preferred embodiment. As with conventional padlocks, in order to make the product more convenient the hoop is free to pivot once unlocked and free of the lock body.

The preferred embodiment proposes to use a piezo-ceramic actuator to control the latching of the hoop in the main body of the padlock and to provide an intermediate buffer mechanism between the actuator and the hoop in order to prevent potential damage to the actuator in the event that an attempt is made to force open the padlock.

Turning now to the drawings, the same reference numerals are used throughout to refer to the same parts. The portable securing device comprises a lock body 10 and a hoop member or hasp 11 which is adapted to be latched into the body 10. As is conventional, a first leg 11a is mounted in the body 10 such that it is capable of axial movement during the locking and relocking procedure as well as pivotal movement once the hasp 11 has been unlocked and a second leg 11 b is free of the lock body.

The hasp 11 is locked into the lock body by means of a latch blade 12 which is moveable towards and away from one leg of the hoop member 11 under the control of an electrically operated locking control device 14. The locking control device 14 includes a plunger 17 and acts such that in one condition will permit movement of the latch blade 12 while in another condition does not permit movement. In the present embodiment, the device is a normally blocked device and requires an electrical signal to be present in order to permit movement of the blade 12.

We currently prefer to utilise the Servocell Active Latch 2 (AL2) the basic operation of which is described in WO 2004/077473. In AL2 a plunger and a pawl are located in a housing, the pawl being engagable with the plunger. A electrically controlled piezo ceramic actuator is provided for moving the pawl towards the plunger. The advantage of using the Servocell Active Latch 2 product is that although it comprises an electrically controlled piezo ceramic actuator, this is located within the plunger itself and so only simple electrical connections are required to be made to the device.

All of the electronic components required by securing device of the present invention as well as the locking control device 14, including batteries, are located within the lock body and are concealed under a plate which is fixed to the lock body 10.

Turning now to figure 2 of the drawings, the shackle or hasp 11 is resiliently biased by means of a spring 20 and it is preferred that the shackle is biased towards an open condition. The shackle 11 is held in its latched condition by means of the locking blade 12 engaging in a recess 21 in the shackle. Movement of the locking blade towards and away from the shackle is permitted or inhibited depending upon the operational condition of the control device 14 by virtue of a projection 21a of the locking blade engaging with the plunger 17 of the control device. It is to be noted that the line of action of the plunger is parallel to the line of action of the locking plate as it moves towards and away from the shackle. Consequently, any attempt to apply excessive force to the shackle in order to brake the securing device, is not transferred to the control device 14. However, a padlock type product has such potential for abuse that an intermediate buffer mechanism is provided to prevent any potential damage the control device 14. In the present embodiment, the buffer mechanism comprises a lever 22 which interfaces with a notch 23 in the shackle. The release lever has a release projection 22a which engages in a camming relationship with the notch 23 and is coupled to the locking blade indirectly via a buffer spring 24. In order to ensure proper seating of the release lever 22, a reset spring 26 is provided.

The operation of the above-described elements will now be described in detail. Because the control device 14 cannot change state while its plunger 17 is under force, the initial operation of the device requires the shackle to be pressed against the action of the spring 20 to unload the plunger 17 and allow it to change state if this is required. Bearing in mind that the control device is a normally blocked device, in the absence of any electrical signal to the control device 14, as the shackle tends to be pushed out of the lock body by the shackle spring 20, the release lever is compressed or in other words moved away from the shackle 11. There is also a tendency for the release lever to pivot and this combined movement applies a force to the buffer spring 24. In view of the fact that the control device is in a blocked condition, the locking blade 12 is unable to move more than any free play in the plunger 17 of the control device 14 and thus all that happens is that the buffer spring 24 is compressed and the shackle remains in its locked condition.

However, in the event that it is desired to open the securing device, it is necessary to energise the control device 14 and this can either be done at the same time as the shackle is initially pressed against the spring 20 or immediately after it. In any event, when the shackle is released by the user after compression, the release lever is again compressed as before but this time when the lever 22 applies a force to the buffer spring 24, and by virtue of the fact that the spring rate of the buffer spring 24 is greater than that of the internal spring which is contained within the control device 14 and which acts on the plunger 17, movement of the release lever causes the locking blade to move away from the shackle 11 and thus remove the locking blade from the recess 21 in the shackle and thus release the shackle.

In order to return the shackle 11 to its latched condition, all that is necessary is for the shackle to be pressed into the main body 10 against the action of the spring 20 until such time as the projection 22a on the release lever 22 meets with the recess 23 in the shackle which is achieved by means of the reset spring 26. This in turn allows the spring 24 to be released which in turn permits the locking blade 12 to enter the recess 21 in the shackle 11 and lock the device in its initial locked condition.

Various modifications may be made to the above basic description. For example, the latching of the shackle into the main body is achieved by means of the locking control device and the locking blade acting on a recess in the arm of the shackle which is retained in the main body. It is equally possible to arrange it so that it is the free arm of the shackle which is latched by this mechanism. Further, various springs are shown as being compression or extension springs and it is possible to rearrange the springs so that where a compression spring is shown it can be replaced by an extension spring depending on the particular design of the apparatus.

It will be appreciated that there has been no description of a device or process by which to input and verify a code to the locking device in order to commence the unlocking process. This is deliberate in view of the fact that there are many suitable arrangements which may be utilised. It is envisaged that access control systems such as biometric scanning, numeric key-codes and RFID tag system etc. may be used for the securing device.

Further, rather than having the device battery powered it may be possible to utilise a form of remote, non-contact code input device which could also inductively provide power temporally to the locking device during the unlocking operation.

Claims

CLAIMS:

1. A portable electronic securing device comprising a lock body (10) mounting a shackle (11) moveable axial between locked and unlocked positions, and an electrically controlled lock release mechanism for allowing the shackle (11) to move from its locked to its unlocked position, characterised in that the lock release mechanism comprises a piezo ceramic actuator device (14) acting on a latch member (12) which is arranged to be received in a recess (21) in the shackle (11) in the locked position, and a buffer mechanism between the latch member (12) and the shackle (11), the buffer mechanism being responsive to movement of the shackle (11) and to prevent axial movement of the shackle (11) being transmitted to the piezo ceramic actuator device (14) in the event that an attempt is made to force the shackle (11) to move from the locked to the unlocked position.

2. A portable electronic securing device according to claim 1 wherein the buffer mechanism comprises a release lever (22) having a portion which engages (22a) with a notch (23) in the shackle (11), the release lever (22) being resiliently coupled to the latch member (12).

3. A portable electronic securing device according to claim 1 or 2 wherein the buffer mechanism comprises a reset spring (26) contacting the release lever (22) for biasing the release lever (22) into engagement with the notch (23) in the shackle (11).

4. A portable electronic securing device according to claim 1 , 2 or 3 wherein the piezo ceramic actuator device (14) comprises a plunger (17) contacting the latch member (12) and a piezo ceramic arrangement for inhibiting movement of the plunger (17) in the absence of an electrical signal.