GB2285479A

GB2285479A - An electrically operated lock

Info

Publication number: GB2285479A
Application number: GB9500067A
Authority: GB
Inventors: Albert Edward Bardy; Michael Leslie Woodrow
Original assignee: FOX THOMAS CO Ltd
Current assignee: FOX THOMAS CO Ltd
Priority date: 1994-01-07
Filing date: 1995-01-04
Publication date: 1995-07-12
Anticipated expiration: 2015-01-04
Also published as: GB9500067D0; GB2285479B; GB9400257D0

Abstract

An electrically operated lock (66) comprising a linear actuator (72), first sensor means (76) for sensing when a part (80) of the linear actuator (72) is in an extended locking position, and second sensor means (78) for sensing when the part (80) of the linear actuator (72) is in a retracted non-locking position, and the first and the second sensor means (76, 78) being such that they control the operation of an electric motor (70) of the linear actuator (72) consequent upon the sensed position of the part (80) of the linear actuator (72) whereby the electric motor (70) only operates when it is desired to cause a predetermined movement of the part (80) of the linear actuator (72). The actuator can be employed to block a fastening bolt or to extend a latch bolt to a deadbolt position. <IMAGE>

Description

AN ELECTRICALLY OPERATED LOCK This invention relates to an electrically operated lock and, more especially, this invention relates to an electrically operated lock comprising a linear actuator.

Vending machines are sited in prominent and isolated positions in public places such for example as bus, rail and underground stations. The vending machines contain money from sales. In order that the machines are ready for use each morning, the machines are left with a money float overnight. This money may be of the order of i100 and it is sufficient to attract petty criminals who break into the machines overnight when the siting areas are either relatively quiet or are closed. The machines incorporate a locking system but it is of a simple design that can be forced open. To combat this problem, there is a need for a more sophisticated locking system which cannot easily be forced open.

It is an aim of the present invention to provide an electrically operated lock which can meet the above mentioned need, and which can also be used for a variety of other purposes including being used generally to lock any door in position in a frame such for example as a door to a safe, a door to a strongroom, or a door to a building.

Accordingly, in one non-limiting embodiment of the present invention there is provided an electrically operated lock comprising a linear actuator, first sensor means for sensing when a part of the linear actuator is in an extended locking position, and second sensor means for sensing when the part of the linear actuator is in a retracted non-locking position, and the first and the second sensor means being such that they control the operation of an electric motor of the linear actuator consequent upon the sensed position of the part of the linear actuator whereby the electric motor only operates when it is desired to cause a predetermined movement of the part of the linear actuator.

The electric motor is thus not always running since a constantly running electric motor would cause the part of the linear actuator to jam up. The linear actuator operates under positional control rather than under servo control.

In one embodiment of the invention, the electrically operated lock is one in which the part of the linear actuator is movable solely between its extended locking position and its retracted non-locking position. Such an electrically operated lock may be especially suitable for use on all sorts of vending machines. The electrically operated lock may also be used on the doors of safes and strongrooms where the part of the linear actuator can be used to block the passage of bolt work that needs to be moved in order to open the door of the safe or the strongroom.

In another embodiment of the invention, the electrically operated lock is one in which the linear actuator includes a spring for moving the part of the linear actuator from its retracted non-locking position to an intermediate locking position which is provided solely by the action of the spring, and in which the part of the linear actuator is movable from the intermediate position to the extended locking position under the action of the electric motor, the extended locking position then being a deadlock position. Such an electrically operated lock may be especially useful for use on doors of premises such for example as security doors to blocks of flats or office premises.

The door can be slammed shut to its intermediate locking position, whereupon the electric motor can operate in order to move the part of the linear actuator still further forward to a second position which is the extended locking position giving the deadlock position.

The electrically operated lock may include time delay means for providing a time delay on the permitted time of opening of a door fitted with the electrically operated lock.

The electrically operated lock of the present invention may include alarm means for use if the lock should become jammed. The alarm means will usually be an audible alarm means. The alarm means may alternatively or additionally be a visual alarm means.

If desired, the electrically operated lock of the present invention may be provided with a manual opening facility via a key or a combination, for example in order to meet relevant safety regulations governing emergency escape of personnel from a secure compartment.

If desired, the electric motor may be employed to move two or more of the parts of the linear actuator in tandem.

Where the electrically operated lock is such that the part of the linear actuator has the retracted non-locking position, the intermediate locking position, and the extended locking position, then the sensor means will normally be such that nothing is sensed when the part of the linear actuator is in the intermediate locking position and therefore the motor is not activated. The sensor means will sense when the part of the linear actuator is in its extended locking position, in order to stop operation of the electric motor.

Retraction of the part of the linear actuator to its retracted non-locking position will also be sensed by one of the sensors in order to stop retraction movement of the part of the linear actuator at a desired position.

The linear actuator can be operated via a key or combination on the door where the electrically operated lock is fitted. Alternatively, in situations such as where the electrically operated lock is fitted to a main door of a block of flats or offices, then the linear actuator can also be caused to be operated remotely, for example by persons in different flats or offices. If the electrically operated lock is actuated for enabling the door to be opened and the door is not opened, then the electrically operated lock advantageously operates to move back towards its extended locking position after an appropriate period of time. Thus the door is once again locked and there is no possibility of the door being left in a shut but unlocked condition.

The part of the linear actuator may be a rod member, a protruding member or any other suitably shaped and appropriate part.

Embodiments of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figures 1 and 2 show different views of part of a vending machine having an electrically operated lock provided thereon in order to restrain a bolt riser part of the machine from unauthorised raising in order to open the door of the machine; Figure 3 is a front view of the part of the machine shown in Figure 1, and on an enlarged scale; Figure 4 is a front view on part of a vending machine; Figure 5 is a sectional view on the line A-A shown in Figure 4; Figure 6 is a section on line B-B shown in Figure 5; Figures 7, 8 and 9 illustrate how the electrically operated lock can be used to stop the bolt work on a door of a safe or a strongroom from being opened; Figures 10 and 11 illustrate in more detail an electrically operated lock that can be used on the various doors shown in Figures 1 to 9; Figure 12 shows how an electrically operated lock can be provided as a rim type lock on a door of a building; Figure 13 shows an electrically operated lock and in particular illustrates how first and second sensors operate; Figure 14 is a section on line A-A shown in Figure 13; and Figure 15 is a circuit diagram for an electrically operated lock of the invention.

Referring to Figures 1, 2 and 3, there is shown an electrically operated lock 2 comprising a linear actuator having a motorised part in the form of a rod member 4. Also shown is a microswitch 6 mounted on a bracket 8. The electrically operated lock 2 is mounted on a bracket 10. A printed circuit board 12 carries the electric circuit for the electrically operated lock 2. When the rod member 4 is in the position shown in Figures 1 and 2, then a bolt riser part of the illustrated vending machine 14 cannot be forced upwardly in order to open the door of the vending machine 14.

Referring now to Figures 4, 5 and 6, there is shown a vending machine 16 provided with an electrically operated lock 18. The electrically operated lock 18 has a linear actuator with a part in the form of a rod member 20. The rod member 20 locates in a cut out portion 22 of a bolt member 24 in order to lock the door of the vending machine 16 closed in its cabinet.

In Figures 4, 5 and 6, the electrically operated lock 18 is shown with a linear actuator 26 and a printed circuit board 28 which carries the electrical components for the electric circuit controlling operation of the linear actuator 26 and more especially an electric motor of the linear actuator 26.

Figures 7, 8 and 9 show a safe 30 having a body part 32 and a door 34. The door 34 is locked by bolt work 36. The bolt work 36 comprises three short bolts 38 which go into the body part 32 and which are connected to a vertical bolt bar 40. Figure 8 shows the bolt work 36 in its retracted open position and Figure 9 shows the bolt work 36 in its non-retracted closed position.

Figures 7, 8 and 9 show how the safe 30 can be provided with an electrically operated lock 42 having a linear actuator. The linear actuator has a part in the form of a rod member 44 which can be used to block or unblock a passage 46 for the long member 40 of the bolt work 36.

Figures 10 and 11 show an electrically operated lock 48 having an electric motor 50 forming part of a linear actuator 52. The linear actuator 52 has a part in the form of a rod member 54. The linear actuator 52 also has a printed circuit board 56 carrying the components forming the electric circuit for the electrically operated lock 48.

Figure 12 shows how an electrically operated lock 58 can be used as a rim lock to fit on a door 60 which closes in a frame 62. The electrically operated lock 58 has a linear actuator with a part in the form of a rod member 64. The rod member 64 is spring biased by a spring (not shown) to an intermediate locking position shown in full lines in Figure 12. In this position, the door 60 can be slammed shut and it will remain shut.

After the door 2 has been shut to the position shown in full lines for the rod member 64, the electric motor of the electrically operated lock 48 then starts up and causes the linear actuator to move the rod member 64 further forward to the position shown in dotted lines in Figure 12. In this position, the rod member 64 is in its extended locking position and the electrically operated lock 58 is effectively deadlocked. It will thus be apparent that the electrically operated lock 58 operates such that on casual shutting of the door 60, the rod member 64 will always be moved to the position shown in dotted lines in Figure 12 and thus the door 60 will always be deadlocked. This provides a good degree of security.

Figures 13 and 14 show an electrically operated lock 66 having a printed circuit board 68 containing the electronic circuit for the electrically operated lock 66. The electrically operated lock 66 has an electric motor 70 forming part of a linear actuator 72. Also, shown is a housing 74 for first sensor means 76 and second sensor means 78. The first and second sensor means 76, 78 are opto sensor means which sense the position of a part of the linear actuator 72 in the form of a protruding member 80. As can be seen in Figure 14, the linear actuator 72 includes a spring 82 and an aperture 84 which is able to be blocked by the protruding member 80 of the linear actuator 72.

Figure 15 shows an electric circuit for the electrically operated locks 2, 18, 42, 48, 58, 66. As can be seen, the circuit comprises the first opto sensor means 76 and the second opto sensor means 78. The first opto sensor means 76 is connected to an amplifier 86 which is itself connected to a forward relay 88 for causing a rod member of the linear actuator to move in a forward direction. The second sensor means 78 is connected to an amplifier 90 which is itself connected to a reverse relay 92 for causing the rod member to move backwardly. As can be seen, the relays 88, 92 are connected to an electric motor 94. The electric motor 94 forms part of a linear actuator. The electric motor 94 is shown operating a part in the form of a locking bolt 96. The movement stroke of the locking bolt 96 is defined by the first and second opto sensor means 76, 78 stopping and starting the electric motor 94.

It is to be appreciated that the embodiments of the invention described above with reference to the accompanying drawings have been given by way of example only and that modifications may be effected. Thus, the vending machine may be for selling any suitable and appropriate goods such for example as tickets, sweets or drinks. The rod member may be of any suitable form and construction and it may be in the form of a piston. The electrically operated lock may generally be used as appropriate on a wide variety of machines, apparatus and installations including safes and strongrooms. The linear actuator may be any suitable motorised arrangement and the electric motor may be attached to or may be remote from the part which moves to the locking position and the non-locking position.

Claims

1. An electrically operated lock comprising a linear actuator, first sensor means for sensing when a part of the linear actuator is in an extended locking position, and second sensor means for sensing when the part of the linear actuator is in a retracted nonlocking position, and the first and the second sensor means being such that they control the operation of an electric motor of the linear actuator consequent upon the sensed position of the part of the linear actuator whereby the electric motor only operates when it is desired to cause a predetermined movement of the part of the linear actuator.

2. An electrically operated lock according to claim 1 in which the part of the linear actuator is movable solely between its extended locking position and its retracted non-locking position.

3. An electrically operated lock according to claim 1 in which the linear actuator includes a spring for moving the part of the linear actuator from its retracted non-locking position to an intermediate locking position which is provided solely by the action of the spring, and in which the part of the linear actuator is movable from the intermediate position to the extended locking position under the action of the electric motor, the extended locking position then being a deadlock position.

4. An electrically operated lock according to any one of the preceding claims and including time delay means for providing a time delay on the predetermined time of opening of a door fitted with the electrically operated lock.

5. An electrically operated lock according to any one of the preceding claims and including alarm means for use if the lock should become jammed.

6. An electrically operated lock according to claim 5 in which the alarm means is an audible alarm means and/or a visual alarm means.

7. An electrically operated lock according to any one of the preceding claims and including a manual opening facility via a key or a combination.

8. An electrically operated lock according to any one of the preceding claims in which the electric motor is employed to move two or more of the parts of the linear actuator in tandem.

9. An electrically operated lock according to any one of the preceding claims in which the part of the linear actuator is a rod member or a protruding member.

10. An electrically operated lock substantially as herein described with reference to the accompanying drawings.