GB2283050A - Remote lock alarm - Google Patents

Description

2283050 Remote Lock Alarm This invention relates to security locks for use

with bicycles, motor bikes, or any other article which is required to be secured against theft.

Our European Patent application No. 89308298.2, published under number 0413065, discloses an alarm lock comprising a U or C shaped bar, which locks into a housing containing an alarm which may be triggered in the event of unauthorised tampering. The housing has a key operated lock, which prevents the security bar from being removed, and also a tamper proof battery compartment so that the alarm cannot be disarmed unless the locking bar is first released.

Although the lock alarm described in the above application has considerably enhanced security compared with known systems, it still suffers from certain other drawbacks which are common to devices of this type, for example, the inclusion of a mechanical locking device makes it susceptible to picking, and in addition, even if the alarm is triggered by an attempt to tamper with the device, the owner may not be sufficiently near to hear the alarm, and others may well ignore it.

Accordingly, the present invention provides a lock alarm of the "U-bar" type, in which the alarm circuitry includes radio transmitter and/or receiver means, whereby the alarm may be arranged to transmit a radio signal, to alert the user, and/or maybe remotely controlled for locking and or arming purposes.

Preferably, the electrical circuitry of the alarm and at least one battery forming a power supply, are contained in a removable cartridge, so that various "modular" electrical circuit designs maybe incorporated, for different versions of the device including various combinations of remote control/radio alarm functions.

Preferably, the alarm body is constructed of a strong metal alloy, and an antenna for the radio system is bonded into an outer casing of ABS or similar material, so as not to be shielded by the metal casing. Alternatively, the "U-bar" of the device may be provided with a plastic coating which incorporates an antenna.

In one preferred embodiment of the invention, the alarm incorporates a radio transmitter which operates as a "pager" and is adapted to transmit an identification signal which may be coded, whereby the receiving means can be arranged to identify one of a number of alarm devices spread over a large area. For example, a number of alarm locks may be used on closed containers in a warehouse or container port and arranged to transmit their paging signals to a central receiving station with an LCD display, which will then indicate which alarm has been tampered with.

In another preferred embodiment of the invention, which is specifically adapted for remote control, the lock incorporates a radio receiver which is adapted to control an electrical actuator, such as a motor or solenoid, to lock or unlock the device, whilst at the same time, arming or disarming the alarm system. In this way, the necessity for an external aperture to insert a key is completely avoided, considerably reducing the possibility of a thief interfering with the mechanism.

Preferably, all of the electronics including the electric actuator mechanism are built into a replaceable cartridge, as in the embodiment described above.

Preferably, the unit is battery operated, and includes circuitry which prevents the actuator from moving the mechanism to the locked position, once the battery power falls below a predetermined level, in order to avoid the possibility that the user will then be unable to unlock it. In a preferred arrangement, the circuitry includes a small very long life backup battery, (e.g., a lithium battery) which can be used only to unlock the unit in the event that the main battery is flat, and of course, in this condition, the alarm will be disarmed.

As in the case of the "paging" arrangement described above, an antenna is preferably incorporated in the outer casing of the device, so as not to be shielded by the metal body, and it will be appreciated that the same device may incorporate both the "remote control" and "paging" features, which can then share a common transceiver and antenna arrangement.

Preferably, the alarm also includes audible and visible indicators, such as a piezo electric siren and light emitting diode indicator, each of which may be selectively activated, in accordance with the users preference for any particular situation.

One embodiment of the invention will be described by way of example, with reference to the accompanying drawings in which:

Figure 1 is a longitudinal cross section through a lock alarm housing in accordance with the invention; Figure 2 is a transverse cross section taken along the line II-II of Figure 1; Figure 3 is a side elevation of one "half shell" of an outer plastic casing of the device of Figure 1; and Figure 4 is a vertical cross section taken on the lines IV-IV of Figure 3; Figure 5 is a longitudinal cross section through one "half shell" of an internal diecast casing; Figure 6 is a vertical cross section on the line VI-VI of Figure 5; Figure 7 is a vertical cross section taken on the lines VII-VII of Figure 5; Figure 8 is a side elevation, taken on the open side, of the other diecast "half shell" of the casing; Figure 9 is a vertical cross section taken on the lines IX-IX of Figure 8; Figure 10 is a longitudinal cross section through an inner plastic sleeve of the alarm lock of Figure 1; Figure 11 is a transverse cross section taken on the lines XI-XI of Figure 10; Figure 12 is a longitudinal cross section of the sleeve of Figure 10, viewed from the other side; Figure 13 is a longitudinal cross section through an inner metal locking tube of the alarm lock of Figure 1; Figure 14 is a longitudinal cross section of the locking tube of Figure 13, taken from the other side; Figure 15 is a transverse cross section on the line XV-XV of Figure 14; Figure 16 is a vertical cross section through a battery housing cap, taken on the lines XVI-XVI of Figure 17; Figure 17 is a plan view of the battery compartment cap of Figure 16; Figure 18 is a longitudinal cross section through an internal electronics module of the alarm lock of Figure l; Figure 19 is a longitudinal cross section taken on the lines XIX-XIX of Figure 18; Figure 20 is a transverse cross section taken on the lines XX-XX of Figure 19; Figure 21 is an alarm circuit diagram; Figure 22 is a circuit diagram of a remote controlled version of the alarm; Figure 23 is a longitudinal cross-section in a vertical plane through a further type of lock alarm housing in accordance with the invention; Figure 24 is a partially broken away underneath plan view of the housing of Figure 23; Figure 25 is an exploded view of the mechanism of the lock alarm of Figure 23, Figures 25a, 25b, 25c, 25d and 25e, respectively illustrating different parts of the mechanism; Figure 26 illustrates the part shown in Figure 25a in detail; and Figure 27 illustrates the part shown in Figures 25b and 25c in more detail.

Referring firstly to Figures 1 and 2, the alarm comprises an elongate housing having a die-cast casing 2, with apertures 4 and 6 which in use, locate a solid "Ushaped" locking bar. An end cap 8 at one end of the housing is removable to allow access to a cartridge 10 which contains the battery and electronic circuitry of the device, and the end cap can only be removed by loosening a locking screw 10 which is inaccessible from the outside of the device, and can only be reached through the aperture 4, by removing the security bar. This corresponds to the arrangement disclosed in our above mentioned European patent application publication no. 04 13 065.

At the other end of the housing, a lock mechanism 14 is mounted in the upper part of the body, and cooperates with a rotatable metal locking tube 16, which includes "keyhole shapeC apertures 18 and 20 which are arranged to lock suitably shaped ends of the security bar into position, when the tube is rotated. once again, this arrangement corresponds to that described in our above mentioned European patent application.

Alternatively the locking tube may be substituted by an elongate flat bar and the ends of the U-bar may be formed with keyhole shaped apertures so that they can be fitted over the bar in only one rotational position.

As illustrated in Figures 3 and 4, the external surface of the lock is encased in a sleeve 22 of ABS material, which is formed with an aperture 24 at one end for removal of the end cap 8, and another aperture 26 at the other end, for access to the lock 14.

Referring to Figures 10 and 11, the metal locking tube 16 is axially located in the housing by means of an insulating plastic tube 28 whose external cross-section is generally elliptical, as indicated at Figure 11. Axially extending slots 30 and 32 on each side of the tube, locate it on corresponding inwardly projecting rails 34 and 36 on the internal surface of the housing, as illustrated in Figure 2 and also in Figures 6 and 7. As will be appreciated from these Figures, the arrangement of the plastic tube is such as to enable the metal locking tube to be easily assembled into the casing, and accurately but rotatably located in position, without the necessity for specially fabricated fastenings or bearing arrangements. As will be noted from a comparison of Figures 1, 5 and 10, apertures 38 and 40 in the die-cast casing are adapted to receive the ends of a flexible security loop, in the form of a steel cable, the ends being secured in position by further "keyhole slots" 42 and 44 in the inner metal tube 16. As will also be seen from a comparison of Figures 13 and 14, which illustrate "mirror image" axial cross-sections through the tube, the key-hole slots 42 and 44 are staggered around the circumference of the tube, relative to the larger keyhole slots 18 and 20 which receive the ends of the security bar.

Figures 16 and 17 illustrate the end cap 8 for retaining the electronics cartridge, in more detail. As illustrated, it will be appreciated from a comparison of Figure 1 and 16 that the end cap is formed as a hollow rectangular box, with one open side, having a threaded aperture 46 in its upper surface, to receive the locking screw 12, the size and shape of the end cap being such that it securely locates the cartridge 10 in position.

Figures 18 to 20 illustrate the internal arrangement of the electronics cartridge in more detail. As shown, the cartridge comprises an elongate "tray" having a lid 48 and being internally divided into a battery compartment 50, and an electronics compartment 52. The electronics compartment houses a PCB 54 carrying an LED indicator 56, a DIL switch 58 for setting various user options to be described below, and a movement sensor 60. A piezoelectric siren 62 is also mounted immediately beneath the lid 48.

The electrical circuitry of the alarm is arranged to be armed by means of a microswitch on the cartridge (not shown) which is engaged by a cam lobe 64 which is formed on the external surface of the locking tube 16 (Figures 14 and 15).

Figure 21 is a circuit diagram of the alarm, and as illustrated, whilst the circuit is live, the battery voltage is monitored at the junction of a capacitor CS (10 MF) and a resistor R20 (1 megohm) by means of a line 100 which is connected to the input of a battery level detection circuit 102, comprising transistors TI, T2, and resistors R1 to R4. When the battery low circuit is triggered, light emitting diode LD1 (56 in Figure 19) is disabled, but line 100 is also connected to the "reset" line so that the LED will flash for 6 seconds, if the battery low circuit has been triggered.

IC1C, IC1D, Cl, R5 to R10, T3, D2, and SW1H make up a flashing circuit for the LED LDI, and the flashing can be disabled if not required, by opening contacts SW1H of the - 8 user setting DIL switch (58 in Figure 19). When the alarm is powered up normally, LD1 flashes for 0.15 of a second every 4 seconds, but if the alarm is triggered IC2 is latched which energises T3, switching R8 and R9 into circuit to alter the time constant. This has the effect of doubling the flashing rate, to 0.15 of a second every 2 seconds.

The security loop is connected across terminals PL2 and PL1, so that they are normally shorted, and if the loop is cut the voltage at PL2 will rise towards the positive rail, triggering IC1F to produce a negative going pulse which triggers the alarm.

A movement sensor circuit is arranged to be triggered by spring switch 102, enabled by user setting switch SW1F, and when the movement sensor is triggered the closure of the spring switch contact causes pulses to pass through IC1G and to charge up capacitor C3, the sensitivity of the circuit being adjustable by means of R15 and SW1G of the user setting switch. When C3 has reached a sufficient voltage, IC1H switches and triggers the alarm.

A 5 - 15 second time out circuit is provided by the arrangement of IC1I, IC1J, C4, R16 to R19, T4, D6, and SW1C. When a negative going pulse is received by IC1I, the circuit is triggered, and the time out duration can be selected by setting SW1C of the user switch. When ICii is triggered, its output energises T4, via R19, and if user setting switch contacts SWIB are closed, an output is produced to drive a pager circuit (Figure 22). If contacts SW1A are closed, the output from T4 also drives a siren oscillator array IC3 whose oscillator frequency can be set by opening or closing contacts SWID of the user setting DIL switch, so as to switch R22 into or out of its parallel connection with R23. The arrangement is such that a sweeping frequency of 3.3 to 4.2 khz can be produced, and the output level can be switched by means of SWIE, connected across R24.

The output of IC3 drives transistor T5 whose collector load comprises a step up transformer Ll which produces a high oscillating voltage of around 225v peak to peak to directly drive a piezo disk, forming the audible alarm.

After the alarm has been triggered, the components IC1E, IC1K, C5 and R20 provide the "reset" signal, so as to automatically reset the circuit after about 6 seconds.

Figure 22 illustrates a more sophisticated version of the circuit of Figure 21 which has the same basic functions but also illustrates the arrangement of the pager transmitter 104 connected to the output of SW1b, and the addition of a remote control module 106. The remote control module is connected to an antenna 108 which is shared with the pager transmitter 104, and also receives an input from the battery low detection circuit 102 which provides an interlock so that, if the battery is low, an alternative supply is connected to the module from a lithium backup battery 110. In this condition the "arm" function of the remote control is disabled and it can only be used to "disarm" the lock. As illustrated the remote control supplies "arm" and "disarm" signals to a motor drive unit 112 which actuates a lock motor 114 so as to normally drive the lock to the engaged or disengaged positions.

Figure 23 and Figure 24 illustrate an alternative mechanical construction of locking mechanism for the lock alarm, in which the end 120, 122 of the U-bar are formed with inwardly facing notches 124, 126, which form detents for respective retractable latch members 128, 130. The latch members 128, 130 are slidably mounted inside the housing 132 of the lock, as explained in more detail below, and are illustrated in Figure 23 in the locked position in which the U-bar cannot be removed. It will be clear from this drawing, however, that when the latch members are moved inwardly, i. e. when member 128 moves to the right and member 130 moves to the left, they will respectively disengage from the notches 124 and 126, so as to unlock the mechanism and allow the U-bar to be withdrawn from the housing.

As illustrated in the drawings, the latch members are slidably mounted in an elongate bracket 134 (Figure 25a) which is in turn rigidly mounted on mounting posts 136, 138 (Figure 25d) and has flanged ends 140, 142 providing anchorage points for respective tension springs 144, 146. The other end of each tension spring is connected to a corresponding anchorage point 148, 150 on the latch member 128, 130, and it will be clear from the drawing that the effect of this is to urge the latch members into the outer position, as shown, which is the normal rest position of the mechanism. It will also be clear from the drawings, that the sloped formation of the ends of the latch members cooperates with the ends 120, 122 of the U-bar in such a way that although the U-bar can then be inserted into the housing, causing the latch members to retract against the force of springs 144, 146, the latch members will then reengage in notches 124, 126 so that the device will be locked.

At the opposite end of each latch member 128, 130, there is a further flanged detent member 152, 154 which engages around a rotatable cam member 156 which is mounted on a barrel type lock 162 in the base of the housing.

The cam 156 has oppositely extending lobes 158, 160, which are so arranged that, when the cam member is rotated anti-clockwise as seen in Figure 24, the lobe 158 engages with the flange 152 of latch member 128, and the lobe 160 engages with the flange 154 of latch member 130, so that the two flanges 152, 154 are urged away from the central, latched position, against the force of springs 144, 11 - 146, so as to disengage the latch members from the respective ends of the U-bar and thus to allow the lock to be released.

It will be appreciated that the arrangement is such that the "open" position of the lock only occurs momentarily, whilst the key is inserted and turned against the spring force. Instead of a cam and barrel lock the device may be provided with a solenoid or similar electrical actuator connected between the flanges 152, 154, so that the lock can be unlocked by remote control using a control circuit of the kind shown in Figure 22.

Claims (14)

CLAIMS:

1. A lock alarm of the "U-bar" type comprising a body into which the ends of a U-bar are locked, in use, and including a radio transmitter arranged to transmit a radio signal to alert the user in the event of an unauthorised attempt to open the lock.

2. A lock alarm of the U-bar type comprising a body into which the ends of the U-bar are locked, in use, and further comprising radio receiving means whereby the lock can be remotely armed and/or locked.

3. A lock alarm according to claim 1 or claim 2 in which the electrical circuitry of the alarm is incorporated in a removable cartridge whereby different versions of the device may be constructed with different combinations of remote control and radio alarm functions.

4. A lock alarm according to any preceding claim in which the alarm body is constructed of a strong metal alloy and has an outer casing of plastics material into which a radio antenna is bonded.

5. A lock alarm according to any of claims 1 to 3 in which the U-bar is provided with a coating of plastics material which incorporates an antenna.

6. A lock alarm according to claim 1 or any of claims 3 to 5 in which the transmitter is arranged to operate as a pager and to transmit an identification signal, and remote receiving means is also provided which is adapted to identify the signal as emanating from one of a plurality of alarm devices.

7. A lock alarm according to claim 6 in which the receiving means comprises a central receiving station having a display which indicates which alarm has been activated.

8. A lock alarm according to any of claims 2 to 7 further comprising an electrical actuator adapted to lock or unlock the device under control of the radio receiver.

9. A lock alarm according to claim 8 in which the locking mechanism has a rotary action and the actuator comprises an electric motor.

10. A lock alarm according to claim 9 in which the housing includes a longitudinally extending rotatable member, and the ends of the U-bar are provided with locking formations adapted to co-operate with the rotatable member, whereby the U-bar can be inserted into the housing in a first rotational position of the rotatable member which is then rotated to a second position in which the U-bar and the rotatable member are locked together.

11. A lock alarm according to claim 8 in which the locking mechanism has a reciprocating action and the actuator comprises a solenoid.

12. A lock alarm according to claim 11 in which the locking mechanism comprises at least one longitudinallyextending retractable latching member which is adapted to engage with a co-operating formation on the corresponding end of the U-bar, whereby the U-bar can be inserted into the housing in a first position in which the latching member is retracted and the latching member is then moved to a second position in which the U- bar and the latching member are locked together.

13. A lock alarm according to claim 12 in which the latching member is spring-loaded into the engaged position.

14. A lock alarm according to any preceding claim which is battery operated and includes a longlife backup battery to enable unlocking of the device only, if the main battery is flat.