GB2463943A

GB2463943A - Lock comprising an accelerometer

Info

Publication number: GB2463943A
Application number: GB0818184A
Authority: GB
Inventors: Stewart Taylor
Original assignee: Cooper Security Ltd
Current assignee: Cooper Security Ltd
Priority date: 2008-10-06
Filing date: 2008-10-06
Publication date: 2010-04-07
Anticipated expiration: 2028-10-06
Also published as: GB2463943B; GB0818184D0

Abstract

A lock comprises a lock mechanism and an accelerometer (figure 3, 2). The accelerometer is arranged to detect rotation of the lock mechanism, which may be about a main axis A of the lock. The accelerometer may be located on the main axis or be mounted on a substrate that lies perpendicular to the main axis. The lock mechanism may comprise a cylinder (figure 1, 3) with a rotatable plug 5. The lock may comprise a radio frequency transceiver (figure 3, 6) for transmitting and receiving data to or from an electronic alarm system, and may be controlled by a microprocessor (figure 3, 4) and powered by a battery (figure 3, 8). A knob may comprise the accelerometer and may be retrofitted to an existing lock. The knob may comprise a button (figure 1, 13) which may be operably connected to the microprocessor to enable an alarm system to arm or disarm the alarm upon a predetermined amount of rotation being detected.

Description

This invention relates to locks. In particular, it relates to locks suitable for use in security systems comprising electronic alarms, and to security systems including such locks.

According to the present invention in a first aspect, there is provided a lock comprising a lock mechanism and an accelerometer, wherein the accelerometer is arranged to detect rotation of the lock mechanism.

The measured rotation can then be used to send signals to an alarm system to arm or disarm an alarm. The signals may preferably be transmitted wirelessly.

The lock preferably has a main axis about which the mechanism rotates, wherein the accelerometer is arranged to detect rotation about the main axis.

The accelerometer may be located on the main axis. The accelerometer may be mounted on a substrate that lies substantially perpendicular to the main axis.

The lock mechanism may comprise a cylinder with a rotatable plug, wherein the accelerometer is arranged to detect rotation of the plug within the cylinder.

The plug may be provided with a keyway at a first end, and a knob at a second end, wherein the plug is arranged such that it may be rotated using a key or using the knob, and wherein the accelerometer is located within the knob.

The plug and the knob are preferably axially aligned with one another.

A radio frequency transmitted or transceiver is preferably included for transmitting and receiving data to/from an electronic alarm system.

The lock mechanism preferably comprises a microprocessor or other control unit arranged to control the accelerometer and radio frequency transceiver.

The lock mechanism preferably comprises a battery operable to power the microprocessor, accelerometer and radio frequency transceiver.

The knob may he provided with a button that is operably connected to the microprocessor such that depressing the button sends a control signal to the control unit and/or enables an alarm system connected (wirelessly or otherwise) to the control unit to arm or disarm an alarm upon rotation, or a desired amount of rotation, being detected.

According to another aspect of the invention, there is provided a security system comprising a lock as defined in any of the above statements.

The security system preferably comprises an alarm system having an alarm control, which is arranged to communicate with the radio frequency transceiver of the lock.

The lock mechanism is preferably arranged to send information to the alarm control relating to the amount and direction of angular rotation detected by the accelerometer.

The lock mechanism is preferably arranged to send information to the alarm control relating to angular rotation detected in a locking direction only when such rotation occurs within a predetermined time from depression of the button on the knob.

The security system is preferably arranged such that the alarm control activates or dc-activates the alarm in dependence on the angular rotation information.

According to a further aspect of the invention, there is provided a method of detecting the rotation of a lock cylinder handle using an accelerometer.

According to a yet further aspect of the invention, there is provided a knob comprising an accelerometer arranged to be retrofitted to an existing lock.

Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of a lock mechanism of a lock according to the present invention; Figure 2 shows a perspective view of the lock mechanism of Figure 1 with a knob casing removed; Figure 3 shows a basic schematic representation of the components housed within the knob; and Figure 4 shows, graphically, alarm status against rotation angle of the lock mechanism.

The term accelerometer, used herein, means a component for measuring acceleration and gravity induced reaction forces.

Figures 1 and 2 show a lock mechanism 1 from a lock in accordance with the present invention. The lock mechanism comprises a cylinder 3, which in the present embodiment is of the euro cylinder type, a plug 5, which is rotatably mounted within the cylinder, a keyway 7, which is provided in the plug and receives a key (not shown) that is used to rotate the plug, and a knob 9.

Whilst the present embodiment is described with reference to a euro cylinder lock it should be appreciated that the invention is applicable to numerous other types of locks.

The lock further comprises a lock case (not shown) in which the mechanism is mounted. The lock case, in use, will he arranged in a door, or similar, such that the knob of the lock mechanism is positioned on the inside of the door and the keyway is positioned on the outside of the door. The knob allows the lock to be operated by hand (without a key) from the inside, since the knob is operably connected to the plug such that rotation of the knob results in rotation of the plug. The plug is provided with a radially extending arm 11, which co-operates with a deadholt that is movably mounted in the lock case and is operable to lock the door shut. The lock may be further provided with a catch and a handle, the catch being operable to maintain the door in a closed position without operating the lock. The catch may also be operated by the lock mechanism, as will be appreciated by those skilled in the art.

The knob is a self-contained assembly, which may be retrofitted to existing lock mechanisms in the place of an existing thumbscrew or handle. The knob houses an accelerometer 2, a microprocessor 4, a radio frequency transceiver 6, a battery 8, and associated circuitry. The battery provides power to the all of the components internal to the knob. The battery is replaceable. The knob comprises a knob casing 10, which is removable to provide access to the internal components, as shown in Figure 2.

The knob is provided with a button 13, which is operably connected to the aforementioned components provided within the knob.

In one embodiment there are three circuits provided, one comprising the accelerometer and microprocessor, one comprising the radiofrequency transceiver and one comprising the battery. These may be mounted on separate printed circuit boards.

The circuits may be mounted on a single printed circuit board. Most preferably all of the circuits are soldered to the printed circuit board(s). Alternative circuit arrangements are, of course, possible. The circuit comprising the accelerometer is arranged in the knob such that the accelerometer is provided in alignment with a main axis (axis A) of the lock mechanism, i.e. the accelerometer lies on the main axis.

However, alternative mounting positions will be readily conceived by the skilled person. The substrate may be mounted substantially perpendicular to the main axis with the accelerometer lying on the main axis. The plug and the knob are also axially aligned with the main axis and are rotatable about this axis.

The accelerometer is a 3-axis accelerometer. However, different accelerometers may be used, as will be readily appreciated by those skilled in the art.

The accelerometer accurately detects the direction and degree of rotation of the plug (in both clockwise and counter-clockwise directions -locking and unlocking directions, which may change depending on the specific lock orientation/configuration). The accelerometer detects rotation with an accuracy of 10 degrees or less.

The lock is preferably provided as part of a security system, which comprises an electronic alarm. The accelerometer, radio frequency transceiver, battery, and associated circuitry are provided to allow a user to activate the alarm by pressing the button and locking the door, and to deactivate the alarm by unlocking the door.

The radio transceiver detects and indicates "set" and "unset" radio transmissions from/to an alarm panel, which controls the alarm. The radio transceiver may be a Scantronic radio transceiver operating at 868.6625 MHz, or similar, having a receive range of about 20m or more from the alarm panel.

The alarm is preferably provided with an electronic sounder, which indicates the current status of the alarm. The sounder may be provided within the knob or within the alarm panel.

The structure and interaction of the components of the lock mechanism and the security system will now be explained with reference to the use of the security system.

When it is desired to activate the alarm, the user must depress the button on the inside of the door. This feature allows a user to lock the door without setting the alarm, if desired. This feature may be omitted. Depressing the button sends a signal to the microprocessor, which sends a signal to the alarm panel, using the transceiver, to confirm that the radio link between the transceiver and the alarm panel is available, and which initiates an activation sequence. The sounder may provide an audible signal to confirm to the user that the link is available and/or that the activation sequence has been initiated. During the activation sequence, the microprocessor is operable to send an alarm set signal to the alarm panel, using the transceiver, when the degree of rotation of the plug detected by the accelerometer has passed a predetermined angular limit in a locking direction. Upon receipt of the alarm set signal, the alarm panel arms the alarm. Rotation of the plug to set the alarm, during the initiation period, may be achieved by rotating the knob, when the user is to remain inside, or by using a key, when the user is to exit the building via the door. The duration of the activation sequence may be set to any predetermined time, most suitably about 30 seconds. Upon expiry of the activation sequence, without rotation of the plug, the alarm remains unset and it will be necessary for the user to initiate a new activation sequence if it is desired to arm the alarm.

To deactivate the alarm, no depression of the button is required, the plug is simply rotated in the unlock direction using either the knob or the key, depending on whether the user is inside or outside the building. The microprocessor is operable to send an alarm deactivation signal to the alarm panel, using the transceiver, when the degree of rotation of the plug detected by the accelerometer has reached a predetermined angular limit in an unlocking direction.

Figure 2 shows the plug in a neutral position, that is prior to rotation of the plug, which represents 0 degrees in the graph of Figure 3.

Figure 3 represents a graph, which represents alarm status versus rotation angle of the lock mechanism. The negative angles on the graph represent rotation beyond the neutral position in an unlocking direction and the positive angles represent rotation beyond the neutral position in a locking direction.

The alarm disable command is set, in the present embodiment, at -36 degrees and +90 degrees and the alarm enable command is set at +540 degrees. The location of the alarm disable limits depends upon the starting angle of the lock mechanism. The limits may be varied as desired in dependence on the lock mechanism, the accuracy of the accelerometer, etc. Considering actions (3), (4) and (1): (3) The user is locking the door and setting the alarm and is starting from the neutral position. They depress the button on the knob to start the activation sequence and within the activation sequence time limit (30 seconds or otherwise) they turn the key (or knob, if they are setting the alarm and remaining inside the building). At the alarm enable command limit of +540 degrees an alarm control signal is sent from the lock mechanism to the alarm control and the alarm is set. Note that the deadbolt is fully extended at +540 degrees.

(4) The user is unlocking the door and un-setting the alarm and is starting from the locked position reached in action (3). The user turns the key (or knob, if they are inside the building). At +90 degrees, reached by rotating the lock mechanism in the unlocking direction, the alarm disable command limit is reached and an alarm control signal is sent from the lock mechanism to the alarm control and the alarm is un-set.

(1) The user is opening the door, which is not deadlocked, and un-setting the alarm. The operation starts from the neutral position. The user turns the key. At -36 degrees, reached by rotating the lock mechanism in the unlocking direction, the alarm disable command limit is reached and an alarm control signal is sent from the lock mechanism to the alarm control and the alarm is un-set.

The limits for un-setting the alarm are set at points before the latch or deadbolt (as appropriate) are fully retracted such that it is ensured that the alarm is un-set before the user is able to open the door and/or enter the building.

Claims

Claims 1. A lock comprising a lock mechanism and an accelerometer, wherein the accelerometer is arranged to detect rotation of the lock mechanism.
2. A lock as claimed in Claim 1, wherein the lock has a main axis about which the mechanism rotates, and wherein the accelerometer is arranged to detect rotation about the main axis.
3. A lock as claimed in Claim 2, wherein the accelerometer is located on the main axis.
4. A lock as claimed in Claim 2 or 3, wherein the accelerometer is mounted on a substrate that lies substantially perpendicular to the main axis.
5. A lock as claimed in any preceding claim, wherein the lock mechanism comprises a cylinder with a rotatable plug, and wherein the accelerometer is arranged Q to detect rotation of the plug within the cylinder.

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6. A lock as claimed in Claim 5, wherein the plug is provided with a keyway at a first end, and a knob at a second end, wherein the plug is arranged such that it may be rotated using a key or using the knob, and wherein the accelerometer is located within the knob.
7. A lock as claimed in Claim 6, wherein the plug and the knob are axially aligned with one another.
8. A lock as claimed in any preceding claim, further comprising a radio frequency transmitter or transceiver for transmitting and receiving data to/from an electronic alarm system.
9. A lock as claimed in Claim 8, further comprising a microprocessor or other control unit arranged to control the accelerometer and radio frequency transmitter or transceiver.
10. A lock as claimed in Claim 9, further comprising a battery operable to power the microprocessor, accelerometer and radio frequency transmitter or transceiver.
11. A lock as claimed in Claim 9 or 10, wherein the knob is provided with a button that is operably connected to the microprocessor such that depressing the button sends a control signal to the control unit and/or enables an alarm system connected to the control unit to arm or disarm an alarm upon a predetermined amount of rotation being detected.
12. A security system comprising a lock as defined in any preceding claim.
13. A security system as claimed in Claim 12, wherein there is provided an alarm system having an alarm control, which is arranged to communicate with the radio frequency transmitter or transceiver of the lock. a)
14. A security system as claimed in Claim 13, wherein the lock mechanism is Q arranged to send information to the alarm control relating to the amount and direction of angular rotation detected by the accelerometer. (\J20
15. A security system as claimed in Claim 14, wherein the lock mechanism is arranged to send information to the alarm control relating to angular rotation detected in a locking direction only when such rotation occurs within a predetermined time from depression of the button on the knob.
16. A security system as claimed in Claim 14 or 15, wherein the alarm control is arranged to activate or de-activate the alarm in dependence on the angular rotation information.
17. A method of detecting the rotation of a lock cylinder handle using an accelerometer.
18. A knob comprising an accelerometer, which is arranged to be retrofitted to an existing lock.
19. A lock substantially as hereinbefore described with reference to the accompanying drawings.
20. A security system substantially as hereinbefore described with reference to the accompanying drawings. a) (\J (\J