GB2190421A - Lock picking detector - Google Patents

Abstract

An optical receiver element 3 is mounted in a transparent part of stationary housing 1c of cylinder lock. Further a luminous element 10 is mounted on grip 6a of a mechanical key 6 for transmitting optical signals therefrom to the optical receiver 3. A source battery is mounted in the key grip 6a for energising the luminous element 3 and switch means provided in the key grip 6a control of energisation of the luminous element 3, e.g. according to pulsed coding. If the optical signal is received when the rotor of the lock is in the correct (unlocked) position then there will be no alarm. <IMAGE>

Description

SPECIFICATION Lock-picking detector The invention relates to lock picking detector means in a key-and-cylinder lock arrangement.

The invention is applicable most advantageously to vehicle cylinder lock arrangements, although the invention is not limited solely thereto. In the following, therefore, the description is directed principally to lock arrangements used in vehicles, but the invention may be applied to other locks, for instance those employed for the front doors of domestic dwellings and in like environments.

One known or conventional vehicle theft-alarm arrangement comprises a door switch which is caused to be on when the vehicle's door is opened, a first detector switch for detecting unlocking rotation of the key-operated rotor of the cylinder lock a second detector switch for detecting withdrawal of the key from the cylinder lock, and a controller adapted to sense either authorized or unauthorized unlocking key-operation, depending upon the signal outputs from these two detector switches.

In such known arrangement, when the cylinder lock is subjected to unlocking operation by use of the mechanical key in the regular unlocking mode and in the theft-preventing position of the key cylinder lock unit (being frequently referred to as 'in the armed condition') the said first switch is operated to ON and the 'armed condition' of the cylinder lock is released. However, if an unauthorized person, without use of the mechanical key, should open the door violently, for instance with the use of a bar or a screwdriver, the door switch as well as the key draw-out sensing switch will be positively turned ON. In such case, however, the unlocking rotation of the cylinder rotor, which rotation is adjudged to be unauthorized unlocking operation, cannot be affected and is prevented by the action of said controller and an audible or visible alarm signal will be issued.

However, the lock cylinder rotor may be caused to rotate by violent force, with the result that the opening of the lock is adjudged by the controller to be 'regular and authorized'.

It is, therefore, an object of the present invention to provide a theft detector arrangement capable of detecting unauthorized unlocking operation as a result of picking.

For attaining this object, and in the inventive antitheft arrangement, the key cylinder assembly is provided with unlock-detecting switch means capable of sensing the unlocked position of the key cylinder rotor, an optical receiver, and switch means adapted for switching 'on' keyside switch means in the event of unlocking operation.

On the other hand, the co-operable mechanical key is provided with another switch means to be switched ON under the influence of the key-cylinderside switch means.

The key is preferably further provided with specifically-selected code-generating means adapted for delivery of a specific and preset code signal when the latter switch means is caused to be ON; and a luminous element to be operatively controlled with the said specific code signal and for feeding an optical signal to the optical receiver.

Preferably the arrangement further comprises a code descriminator adapted for delivery of a coincidence signal when the specific code signal from said luminous element is in coincidence with a preset code signal and there is coincidence between the two signals.

Conveniently, further provided is a picking signal output means adapted to deliver an output when there is no output from the code descriminator, while the unlock detecting switch means does deliver an output.

Based on the foregoing, therefore, more specifically defined, the invention provides a lockpicking detector system in a key-and-cylinder lock arrangement, comprising: a key cylinder unit comprising a stationary housing and a rotatable rotor; a mechanical key comprising a grip and a stem rigidly connected with each other; an optical receiver element mounted on the stationary housing; a luminous element mounted on the grip for transmitting an optical signal therefrom to the optical receiver; a source battery mounted in or on said grip for energising the luminous element; and switching means adapted for on/off control of electrical energisation of the luminous element depending upon the rotary position of the rotor.

In a development, the picking detector arrangement is such that the switching means is off when the rotor is kept in its locked position, while it is switched to on when the rotor is brought to its unlocking position.

The arrangement advantageously further comprising a specific code generator mounted in the grip and adapted for on-off control of the luminous element in accordance with a specific code signal delivered from the code generator.

The above further objects, features and advantages of the invention will become more apparent from the following detailed description with reference of the accompanying drawings, in which: Fig. 1 is a sectional elevation of a cylinder lock unit of a preferred embodiment of the arrangement of the invention; Fig. 2 is a perspective view illustrating the cylinder lock unit and a mechanical key with its stem inserted into the cylinder lock unit; Fig. 3 is a perspective view of the cylinder lock unit, with the mechanical key withdrawn; Fig. 4 is an enlarged sectional elevation of the mechanical key; Fig. 5 is a horizontal section of the key; Fig. 6 is a block diagram giving details of circuitorywhich is housed in a grip portion of the mechanical key;; Fig. 7 is a block diagram illustrating a controller circuit which is to be mounted on an automotive vehicle in which the lock arrangement is used; Fig. 8 is a side view of a modified embodiment of the mechanical key; and Fig. 9 is a sectional side view of a further modified embodiment of the mechanical key.

Similar reference numerals have been allocated to similar parts throughout the various figures.

In Figs. 1 to 3, reference numeral 1 indicates a key cylinder unit. Reference numeral 2 indicates a transparent protector, preferably made of acrylic resin, fixedly mounted on top of the stationary cylinder housing which, in turn, accommodates a rotatable rotor Ib of the unit 1, the front face which is indicated at la. Reference numeral 3 indicates a light-receiving element, preferably sensitive to infrared light, embedded in the protector 2. The unit is shown with its components in a position corresponding to the unlocking condition of the unit 1.

The reference numeral 100 indicates diagrammatically a series of conventional plungers of the lock unit, actuatable by means of a key 6 in conventional manner. The reference numeral 101 represents a key-insertion.opening, whilst numeral 102 indicates a front cover in which the said opening 101 is formed.

A pair of operating magnets 4a, 4b are mounted diametrically oppositely within the housing 1c and in close proximity to the front surface la, as schematically illustrated in Fig. 3. These magnets act as switching-on means for switch means 8 of key unit 6, as will be described more fully later.

Reference numeral 5 indicates an unlockingsensing switch means which is arranged at an appropriate position in the cylinder housing 1c. This switch means 5 is adapted for sensing unlocking rotation of the cylinder rotor l b, to sense mechanical code coincidence, as will be more fully described.

In Figs. 4 and 5, the key unit 6 is shown in more detail. As will be seen from these drawings, the key unit 6 comprises a moulded grip position 6a, while numeral 6b indicates a key blade portion of the key unit 6.

The grip portion 6a is fabricated as a thin box-type grippable housing which houses a power source in the form of a battery 7, switch means, preferably a leaf switch 8, as shown in Fig. 4, code-generating means 9, a luminous element 10, preferably an infra- light-issuing luminous diode, and a further luminous diode 11. As can be seen from Fig. 4, the two diodes 10 and 11 are mounted at diametrically opposite positions on the grip portion 6a and at specific distances from the root portion of the key blade 6b in such a way that these two diodes 10, 11 are each partially exposed at the front of the body portion of the gripper 6a and are arranged one at each side of the blade 6b. The switch 8 is mounted on the inner surface of part of the housing wall of the gripper 6a, substantially in opposition to the root end of the key blade 6b.

When the vehicle's driver, or other authorised person in possession of the key unit 1, inserts the key blade 6b of the latter into the key insertion opening 1 d of the rotor l b and turns the key until it reaches the unlocking position, the switch 8 is brought into the proximity of the operation magnets 4a and 4b. As a result, the switch is actuated and switched to ON, while at the same time the luminous element 10 is positioned in alignment with the light reception element 3.

Turning now to Fig. 6, this figure is a schematic diagram of the circuit included and housed in the key grip portion 6a.

Reference numeral 12 indicates a source switching circuit which is shown as a block and which will be caused to be actuated when the switch 8 becomes ON under the influence of the operation magnets 4a and 4b upon unlocking turning movement of the key 6, as was described above.

When the source switching circuit 12 thus becomes ON, and the code-generating means 9 is thereby operated, the luminous element 10 is energised and a specific optical code signal is delivered therefrom.

As shown in Fig. 6, the code-generating means 9 comprises a reset circuit 13, an oscillator circuit 14, an output circuit 15, a frequency divider 16, a ROM 17 for the specific code signal, an output control circuit 18, and a pulse counter all of which are arranged and connected as shown.

When the said circuit 12 is caused to actuate, the reset circuit 13 is actuated for switching the ROM 17 to its data-initiated condition, as a result of which the oscillator circuit 14 is activated to deliver a rectangular carrier signal, of 30-50 KHz, to both the output circuit 15 and the frequency divider 16.

Upon reception of the rectangular wave carrier signal, at the output circuit 15, the luminous element 10 is energised through transistor Tr. On the other hand, at the frequency divider 16 the input rectangular wave carrier signal is subjected several times to frequency division, e.g. to 1/16 or 1/32, and the frequency divided final stage signal is fed to the ROM 17 which is thereby actuated and delivers a specifically preselected serial pulsed specific code signal. By this operation, the operation signal delivered through the output controller 18 and the output circuit 15 to the luminous element 10 is pulse-modulated with the specific code repetition signal. At this stage, the luminous diode 11 is illuminated for indicating that the specific code signal is being generated by the luminous element 10.

On the other hand, the output from the ROM 17 is delivered also to the pulse counter 19. When this pulse counter 19 has counted the specific code signal n-times, it delivers a signal to the source switching circuit 12, which then ceases its operation.

Fig. 7 shows the circuitry of a vehicle-side controller 20 which comprises a source switching circuit 21 which is caused to operate when the unlock sensing switch means 5 senses a keyunlocking operation, thus becoming ON; a specific code discriminator means 22 adapted to deliver a coincidence signal, preferably an H-level pulse signal, for a certain predetermined time period, when the light-reception element 3 receives a specific signal which is then compared with the previously preset code signal and there is a coincidence between the both; and lock-picking signal output means 23 adapted to deliver a picking signal, when no coincidence signal is delivered from the discriminator means 22, and when, however, there is an output from the unlock detecting switch means 5, thus becoming ON.

The specific code discriminator means 22 comprises: a signal receiver circuit which comprises a turn tuning circuit 24, a carrier amplifier circuit 25 and a detector circuit 26 adapted for amplifying and detecting the specific code signal received at lightreceiving element 3; and a specific code discriminator 27.

The lock-picking signal output means 23 comprises: a power-on/reset circuit 28 operable from the source-switching circuit 21; an output latch circuit 29 whose Q-output is at L-level when the latter is reset from the power-on/reset circuit 28; and AND-circuit 30; a NOR-circuit31; an alarm latch circuit 32 and an inverter 33.

In the controller 20, when the unlocking sensing switch means 5 becomes ON, the reception circuit is set to its standby condition. Then, the power-on/ reset circuit 28 is operated and output latch circuit 29 is reset, its Q-output becoming at L-level. On the other hand, the output from the AND-circuit 30 will be at L-level, since one input terminal which is in connection with the Q-output latch circuit 29 is kept at L-level and the other input terminal which is in connection with the unlock detecting switch means 5 is kept at L-level. The output of the NOR-circuit 31 will be at H-level, since its two inputs are kept at Llevel.Under these conditions, the alarm latch circuit 32 is caused to set, its Q-output thereby being latched to H-level, and through the inverter 33, even if the unlock-detecting switch means 5 should become OFF, the source switching circuit 21 is kept at its operating condition.

Under these conditions, when a specific code signal is delivered from the luminous element 10, the light-receiving element 3 will receive this code signal and the thus received signal is then amplified and detected through the circuits 24, 25 and 26 and fed to the code discriminator circuit 27. Then, this signal will be compared thereat with the preset code signal, and when there is a coincidence between the two, a pulse signal kept at H-level is delivered for a predetermined time period. At the same time the output latch circuit 29 is brought into its set position, its Output thereby being changed from L-level to H-level; the alarm latch circuit 32 will thus be reset to change its Q-output to L-level. Therefore, a related alarm system (not shown) will not receive a picking signal.

When the pulse signal of H-level is not delivered for a predetermined period of time from the discriminator circuit 27, or in other words, when there only the output signal from the unlockdetecting switch means 5 prevails, the Q-output from the alarm latch circuit 32 is at H-level, and, thus a picking signal will be delivered to the alarm circuit.

As can be seen, a delay circuit 34 is provided between the output terminal of the AND-circuit 30 and an input terminal of the NOR-circuit 31, for providing adjustability of the time lag existing between the triggering time of the unlocking sensing switch means 5 and the practical establishment of the regular unlocking condition.

In the foregoing embodiment, only one luminous element 10 is provided and is satisfactory for a lock arrangement having a non-reversible key. However, with the use of a reversible key, such an arrangement will be insufficient for attaining the objects of the invention. For this reason, in the modified key arrangement 6' shown in Fig. 8, two luminous elements 10 are employed.

In, the case of a further modified arrangement shown in Fig. 9, the switch means 8 of the key 6" is designed and arranged in such a way that the switch 8 is kept ON when the key is inserted and kept in position. In this modified key, the operating or front surface 1 a acts as switch-on means for a switching lever, bar or- pusher 8a which is brought into its operating or effective position when the key stem 6b has been inserted into the insertion opening as at id in Figs.1 to 3.

In the following, various merits and advantages of the invention are set forth only briefly.

(1). With the inventive cylinder and key unit, both the mechanical code coincidence and the optical specific code coincidence must be established for adjudging regular and authorised lock-unlocking operation.

With mechanical code coincidence only, the keying operation will be discriminated or sensed as unauthorised lock-unlocking. Therefore, pickinglyexecuted lock-unlocking operation with a key is detected in an easy way.

(2). The specifically selected code signal will be conveyed or transmitted only when the key stem is inserted in position into the cylinder and a lockunlocking operation is executed. Therefore, an unauthorised person cannot intercept the specific code signal.

(3). By the combination of the mechanical code and the specific optical code, the range and number allocated to key-and-cylinder sets can be considerably increased.

(4). Since the specific code signal is delivered from the luminous element 10 to the light receiver element 3 by the regular keying operation, it is achieved with the regular locking and unlocking operations.

(5). The use of optical signals ensures that disturbance from extraneous wireless signals and or extraneous magnetism are effectively avoided.

(6). Theft by use of a magnet or the like can be effectively prevented.

(7). Battery exhaustion can easily be detected, since the luminous element is arranged in and at the key side.

Claims (5)

1. A picking detector arrangement in a key-andcylinder lock arrangement, comprising: a key cylinder unit comprising a stationary housing and a rotatable rotor; a mechanical key comprising a grip and a stem rigidly connected to each other; an optical receiver element mounted on the stationary housing; a luminous element mounted on the grip for transmitting an optical signal therefrom to the optical receiver; a source battery mounted in or on the grip for energising the luminous element; and switching means adapted for on/off control of electrical energisation of the luminous element depending upon the rotary position of the rotor.

2. A picking detector arrangement as claimed in claim 1 wherein the switching means is off whilst the rotor is in its locked position, and is on when the rotor is brought to its unlocked position.

3. A picking detector arrangement as claimed in claim 1 or 2, further comprising a specific code generator mounted in the grip and adapted for onoff control of the luminous element in accordance with a specific code signal delivered from the code generator.

4. A picking detector arrangement substantially as hereinbefore described with reference to and as illustrated in Figs. 1 to 7 of the accompanying drawings.

5. A picking detector arrangement as claimed in claim 4 but modified substantially as hereinbefore described with reference to Fig. 8 or to Fig. 9 of the accompanying drawings.