ELECTRONIC LOCKS FOR DOORS

Abstract: An electronic lock for a door includes a built-in generator (20) for generating electrical energy for operating an electronic code recognition circuit and energising a lock-release solenoid when appropriate. The generator (20) is linked to the door handle spindle (31) via a resilient mechanical energy storage device (24) which is "wound up" during the initial part of turning of the handle and tripped at a predetermined point to release stored energy into the generator (20).

Description: " ELECTRONIC ^ LOCKS TOP. DOORS" Technical Field Tills invention relates to electronic, locks for doors. Background Art It iias already been proposed to substitute for con¬ ventional mechanical door locks, systems of various sorts in which a "key" is recognised by an electronic circuit -which, enables the locking bolt to be Vithdra-wn. Since electronic circuits require pover previously proposed electronic locks have required a battery to be incorporated in the lock hous¬ ing, the provision of mains -wiring to a lock being undesir¬ able. If, ho-wever, a householder fails to change his lock battery it -will be impossible to open the door from outside and the householder may have to resort to breaking in 'to his oτ.τα property. The object of the present invention is to provide an electronic lock in -which no battery or mains supply is req red, Disclosure of Invention In its broadest aspect the invention resides in an electronic lock comprising the combination of an operating member for displacing a locking element, an electronic cir¬ cuit controlling the operation of the lock and electrical generator means- mechanically connected to the operating member so as to generate electrical power for the lock and its electronic circuit when the operating member is moved. More particularly, an electronic lock in accordance vith the invention comprises a body, a lock operating member movably mounted on said body, a lock bolt movably mounted on said body, electrically operated means ' for enabling movement of the operating member to cause displacement of the bolt, an electronic circuit controlling said electrically operated means and responsive to a coded signal derived from a key element so as to enable movement of the bolt only -when a specific coded signal or one of a small number of specific BAD ORIGINAL codec signals is received and electrical generator means mechanically connected to the operating member so as to generate electrical power for said electrically operated means and said electronic circuit --.-hen said operating member is moved. Preferably the generator means includes resilient means driving!" connected to the- operating member so as to store energy during initial movement of the operating emb release means operably by the operating member to release said resilien ' means and connecting means connecting the resilient means to an electrical generator so that said resilient means "when released drives the generator, contin ing movement of the operating member displacing said bolt ;he said specific coded signal is received. Brief Description of Drawings "" In the accompanying drawings:— Figure 1 is a perspective view of one ex mple of a lock in accordance with the present invention in position on a door, Figure 2 is a part-sectional view of a generator and drive mechanism therefor incorporated in the lock of Figure 1, Figure is a fragmentary section on line 3-3 -in Figure 2, Figures to 6 are part-sectional views of a lockin mechanism incorporated in the lock of Figure 1 in different statesj Figure 7 ±s 2. circuit dia ≥si of an electronic cir¬ cuit forming part of the lock, Figure 9 shows a matrix; member forming a part of the electronic circuit; Figure 10 is a circuit diagram showing a modificatio to Figure 7, and BAD ORIGINAL ^^y E Figure 11 is a diagrammatic representation of a more coaplerc electronic circuit px"oviding multiple;; operation. Best I-iode of Carrvin Out the Invention Referring firstly to Figure 1 the lock includes a face plate 10 intended to be attached to the edge of a door in which the lock is used. Projecting from this face plate is a locking element 11 in the form of a bolt, and an auxiliary bolt 12, the purpose of which will be described hereinafter. ' Movement of the locking bolt 11 is achieved by means of an operating member in the form of a lever handle 13 coupled to the locking mechanism (see Figures k to 6) by a ' square spindle (not shown in Figure l). A base plate Ik on which the handle 13 is carried, is formed with a rectan¬ gular recess l a which is shaped to receive a rectangular magnetic key card 1J5, Turning now to Figures 2 and 3 ? there is shown a generator 20 in the form of a permanent magnet alternator which is used to provide electrical power for operating the lock and its electronic circuitry. The alternator 20 has a drive shaft 21 on -which there is a pinion 22 connected to shaft 21 by a one-way clutch (not shown in detail). The pinion 22 meshes a gear segment 23 pivotally mounted on the lock casing and connected y a linkage to a spring drive mechanism operated by the handle 13 of Figure 1. The spring drive mechanism includes a main energy storage spring 2k which is contained within a- hollow guide 25 on the lock casing. A plunger member 2β is slidably mounted on the guide 25 and the spring 2k is compressed between this member 2o and the guide 25. A roc 2? attached to the plunger 2'δ projects from the guide 25 and is connect¬ ed by a first link 28 to one end of a lever 29 pivotally mounted intermediate its ends on the lock casing. The other end of lever 2 is ' connected by a second link 30 to the gear segment 23 so that -movement of the plunger 26 along the guide 25 causes rotation of the gear segment 23 and thereby BADORfGfNAf of the pinion 22. The plunger 2β is provided with a driving connectio to the square spindle 31 already referred to. This connec tion includes a slide member 32"- slidably mounted on the guide 25 and connected by a link 33 o n arm 3^ on the square spindle 31• The slide 32 has a detent 32_a, thereon which engages with a spring-loaded detent 35 mounted on th plunger 26. This detent 35 is connected to a trip-lever 36 which coacts with a projection 37 on the lock case. hen the handle 13 is turned, the arm jk turns cloc wise as viewed in Figure 2 and displaces the slide 3 down wardly. The plunger 26 is carried downwardly with the sli 32 compressing the spring 2k and causing the gear segment 23 to turn in an anti-clockwise direction. The unidirecti al clutch associated with the pinion 22 overruns in this condition so that the alternator shaft 21 is not driven. ϊHαen the handle 13 has been turned through about 60 , the trip-lever 3 contacts the projection 37 and displaces the detent 35 out f engagement with the detent 32_a. The spring 2k now operates as a motor which drives the plunger 26 back upwardly, turning the gear segment 23 in clockwise direction and thereby driving the alternator.. The arrangement described in which mechanical"energ is stored and then released to drive the alternator, ensur that the alternator is always driven consistently, irres¬ pective of the speed at which the handle is .turned by the user. The energy for driving the alternator is collected over a relatively large angle of rotation of the handle so that the torque requirement can be kept reasonably low. T stored energy is released relatively quickly. Turning now to Figures k to 6, the locking mechanis includes a cam kC driven by the square spindle 31• This cam kO has two functions namely firstly to turn a lever kl pivotally mounted on the lock case and providing one part a drive connection between the spindle 31 and the main bolt 11, and secondly to displace a catch slide k2. The main bolt II is secured to a U-shaped member k , on one limb of which a plate kk is captive . This plate k coact≤ with an arm k pivotally mounted on a bracket k6 on the other limb of the ϋ-shaped member k3• The plate kk and the arm k5 have in erengageable detents 44_a, 4 _a thereon which are disengaged from one another in the locked condi¬ tion shown in Figure 4, but inter.engaged in the unlocked condition shown in Figures 5 -and 6. A peg 4la on the lever 4l is engageable with the arm k5 , so that, in the condition shown in Figure 3 5 turning of the spindle 31 > ~ &a.s resulted in the lever kl turning anti-clockwise so that peg 4la drives the lever k5 , the plate kk, the U-shaped member k3 and the bolt 11 as an assembly to the right. In the locked condition shot-.n in Figure k turning of spindle 31 turns the lever kl . but since detents 44a. and 5_a are disengaged arm k can turn freel* in a clockwise direction and no movement is imparted to the plate kk or the U-shaped member 43 which carries the main bolt II.. The position of the plate kk is determined by the position of a vertically siidable latch piece 7 , a spring 48 acting between the U-shaped member 3 and the plate 44 urging the plate 44 to the position shown in Figure 4. The latch piece 7 is normally urged by -a spring (net nαwn.) to the position shown in Figure 4, but can be lifted to the raised position it occupies in Figure 5 t>y the action of a solenoid -which operates a pivoted L-shaped armature 49a. which contacts a follower 50 on the latch piece 47. The follower 50 is engageable with the underside of the plate 44. The latch piece 4 has a detent portion which engages the catch slide 42 when the latch piece 4 is raised and the handle 13 is turned far enough for cam 40 to permit sliding movement of catch slide 42 to the right as ' viewed in Figure 5. This ensures that the latch piece 47 } BAD ORIGINAL once raised, remains raised for as long as the handle is kept in its turned position. The lower end of the latch piece 44 also coacts with the auxiliary bolt 12, so that as viewed in Figure 6 the latch piece 44 is maintained in its raised position by the auxiliary bolt 12 when the latter is extended by its spring-loading when- the door is open. " When the door is closed, as in Figures 4 and 5 > the auxiliary bolt is urged horizontally into the lock casing to align a slot 12a in the bolt 12 with the vertical latch piece 44. Thus, when the handle is turned to open the door, t solenoid 9 is not energised by the alternator when the latter operates, latch piece 47 is not raised and no motio Is transmitted to the U-shaped member 4 and the main bolt 11 - i.e. the door remains locked. If, on the other hand, the solenoid is energised latch piece 47 is raised and is latched in its raised position by the catch slide 42, so that continued tuining of "the handle 2.3 withdraws the bolt, permitting opening of the door. Release of the handle wit the door open causes catch slide 42 to move out of engage¬ ment with latch piece 7, the latter then being held raise by the auxiliary bolt 12. On closing of the door, auxili¬ ary bolt 12 is driven back into the lock casing, causing latch piece 47 to drop back to the position shown in Figure so that the door is relocked. It will be appreciated that various springs require for the proper operation of the mechanism of Figures 4 to 6 have been omitted for the sake of clarity. These springs consist of a spring acting on bolt 11 or member 43 to urge these to the left as viewed in Figures 4 to 6, a spring acting downwardly on the latch piece 47, a torsion spring acting on lever 4l and urging it clockwis , and a torsion spring acting between bracket 46 and arm 5 -urging the latter counter-clockwise. ΛO on ^ C:H Turning now to Figure 7 » one example of the electron¬ ic circuit which controls the energisation of the solenoid 49 ~0γ the alternator 20 is shown. The alternator stator winding 20 is connected to the input terminals of a bridge rectifier R, the output terminals of which are connected to a positive supply rail 5 and a negative supply rail 3 * A capacitor C_ is connected across the alternator stator winding, A storage capacitor C is connected between the rails 2, 53 * A zener diode ZD- has " its cathode connected to the rail 52 and its anode connected by a resistor R_ to the rail 53 * A resistor R 2 connects the anode of -zener diode ZD. to the gate of a thyristor _ , the anode of which is connected to the collector of a pnp transistor Q„. The emitter of the transistor Q 2 is connected to the rail 52 and its base is connected by a resistor R and the solenoid winding 49 in series to the rail 53 * The cathode of the thyristor 0., is connected by a resistor R_ to the cathode of a second zener diode -Z p which has its anode connected to the rail 53 * Another thyristor Q,„ has its anode connected to the rail 2 and its cathode connected by the winding 49 to the rail 53 » a diode D being connected across the wind¬ ing 49 to protect the thyristor C . and the transistor Q ≥ from the effects of cessation of current flow in the wind¬ ing 49. The gate of thyristor Q is connected by a resistor R_ to the output terminal of an AND gate G which has a plurality of .inputs from a matrix connector device ^ which is unique for each different lock. As shown in Figure 9 the matrix connector device may conveniently be in the form of a piece of double-sided printed circuit board 55 between two edge connectors 56, 57. The board 55 li s straight parallel conductor tracks on both sides extending from one edge to the other. For example, for a sixteen-channel system the board 55 has sixteen tracks on each side, with the tracks on one side offset from those on the other side. In Figure 9 the tracks on one side are shown in full lines and those on the other side in broken lines. The edge connector 5 " has adjacent contacts connected together in pairs so that each pair -contacts one track on each side of the board, but shares a common output terminal connected t an input of the gate G. In the l6 channel system there ar sixteen such outputs. The connector 57 ka≤ 32 separate input terminals. To distinguish the boards 55 of differen locks from one another a pattern of holes is drilled in th board 55 to break one track of each pair of tracks. The arrangement of the tracks in offset relationship on opposi sides of the board enables each track to be broken in this way without disturbing adjacent tracks-. The drilled holes may be arranged on any of several different lines along th board to avoid too much weakening of the board along any particular line. The input terminals of the connector 57 _ςe connect ed to the output terminals of a plurality of integrated hall-effect devices HE_ , HE„.«... HE which have input terminals connected to the anode of zener diode ZD„ and to the rail 53 * Bach integrated hall-ef ect device is of kno form such that it produces a logic-level signal at one out put terminal if a magnetic south pole is close to the devi when power is applied to the input terminals, or a logic- level signal, at the other output terminal if a magnetic north pole is closed to the device, when power is applied. As shown in .Figure 8 the integrated hall-ef ect de¬ vices are incorporated in the base of the recess l4a in the plate 14. In the example shown the sixteen devices ar arranged in a square array. The key card 15 incorporates magnets 2-L, , M 2 « ..........M which may be printed or other¬ wise formed to provide either north or south poles on the face of the card which is intended to be adjacent the hall- effect devices when the card 15 is laid in the recess l4_a the magnets are arranged in the same square array as the devices HE, to HE . 1 n ( c:ir- In use , when the alternator 20 is driven a voltage appears between rails 52 and 53 and energy is stored in capacitor C . when the voltage between rails 5^- and 53 rises high enough to break down zener diode ZD.. , thyristor . is fired, and since transistor Q. ? is biased on at this stage by base current through the winding 39 (of insuffici¬ ent magnitude to open the lock) current flows through resistor R_ and zener diode ZD ? ., establishing a zener- stabilize power supply for the integrated hall-effect devices and the gate G. If the key 15 corresponds to the board 55 the correct output terminals of the devices HE., to HE will be connected by the board 55 to the inputs of the gate G, vhich will produce an output which fires thyristor Q._. This results in energisation of the solenoid 49 to allow opening- of the door and also causes transistor ? to turn off, thereby cutting off the power supply to the hall-ef ect devices and the gate G, and saving .as much as possible of the energy stored in the capac itor C or energising the solenoid 49. I the modification shown in Figure 10, one of the integrated hall-effect devices (HE 2 ) has a NOR gate G connected to both of its output terminals, the output of this NOR being connected to appropriate input of the gate G instead of the corresponding output terminal of the conn¬ ector 5^ (or as well as the latter output terminal provided both of the associated tracks of the board 55 are interrup¬ ted). Tfith this modification the key card will only be recognised if there is no magnet at the key array position corresponding to device HE 2 in the hall-effect device array, It will immediately be appreciated that the use of a gate G at one or more positions in the array increases the number of combinations available from 2n to 3n-1 i.e., from 65j53 to 43,046,720 in the case of a sixteen channel system. Various other logic alternatives can also be employed to allow multi-level master keying operation. Turning finally to the circuit shown diagrammatical in Figure 11 a multiplex operation system is envisaged enabling a still greater number of combinations to be employed, in this case a 6 x 6 matrix of hall-effect devices being utilized. The multiplex operation is contro led by a counter 60 shown as a seven stage counter of the type in which only one stage output is high at any given time, the remaining outputs being in a high-impedan.ce "floating" state. A monostable circuit βl is arranged to provide a reset pulse to the counter 60 when the thyristor _ (Figure 7) turns on. Six of the outputs of the counter 60 provide power to the six columns of hall-effect devices, one column at a time. The outputs of the six hall-effect devices in each column form a 12-bit digital word. The same six outputs of the counter 6θ supply signals to the end connector 57' of the matrix connection device 5^- > so that for each output one. end of a different twelve strips in the board 55' are energised. The contacts of the other connector are interconnected in adjacent groups of six, so as to provide a 12-bit digital output dependent on the pattern of holes in the board 55 * These two 12-bit digital words are applied to the two data word inputs of a 12-bit digital comparator circuit 62, the A=B output of which is connected to the trigger input of a monostable circuit 63 the output of which is connected to the CLOCK input of the counter 60. Thus when the thyristor .. turns on the counter 60 is reset and provides an output at its J. output terminal, - thereby energising one column of hall-effect devices and the corresponding twelve strips of the board 55 r • £f the resulting two 12-bit words are equal, the counter 60 is clocked and the 3 output goes high. Thus the "key code" is compared line-by-line with the code held on board 55 with the counter 60 being clocked each time the two words are equal. ∑n the event of any pair of words failing to coincide the cycle stops. After all six stages output J_ of the counter goes high and this fires the thyristor _ to -unlock the door. It will be noted that the above described arrangement permits "three-level" logic without any additional compon¬ ents being necessary. " ivhere there is to be no magnet at any specific array position on the key card, both associ¬ ated strips on the board 5 ' are drilled through, whereas only one or the other is drilled through if a magnet is to be present. In mass production the preparation and storage of the boards 55 τ and corresponding keys can easily be con¬ trolled, the board 55 l being inserted as a last stage of production and one or more key cards being inserted with the lock on packaging. The keys could be produced first and used to programme an automatic machine for drilling the boards 55' or vice versa. The invention may also be applied to more sophistic¬ ated lock systems utilizing non-volatile memories for storing the acceptable key code or codes for each lock, such memories being electronically re-programmable to change these codes whenever required.

Claims: CLAIMS 1. An electronic lock for a door comprising the combin ation of an operating member for displacing a locking element, an electronic circuit controlling the operation of the lock and electrical generator means mechanically connected to the operating member so as to generate electr cal power for the lock and its electronic circuit when th operating member is moved. 2. An electronic lock for a door comprising a body, a lock operating member movably mo-unted on said body, a lock bolt movably mounted on said body, electrically operated means for enabling movement of the operating member to cau displacement of the bolt, an electronic circuit controllin said electrically operated means and responsive to a coded signal derived from a key element so as to enable movement of the bolt only when a specific coded signal or one of a small number of specific coded signals Is received and electrical generator means mechanically connected to the operating member so as to generate electrical power for sa electrically operated means and said electronic circuit wh said operating member is moved. 3. An electronic lock as claimed in claim 2 in which said generator means comprises resilient means drivingly connected to the operating member so as to store energy during initial movement of the operating member, release means operable by the operating member to release said resilient means and connecting means connecting the resili ent means to an electrical generator so that said resilien means when released drives the generator, continuing move¬ ment of the operating member displacing said bolt if the said specific codec signal is received. 4. An electronic lock as claimed in claim 3 i which • said connecting means incorporates a one-wa3 r drive device whereby driving of the electrical generator during said initial movement of the operating member is prevented. 5. An electronic lock as claimed in claim 4 in which the electrical generator comprises a permanent magnet alterna¬ 6. An electronic lock as claimed in claim 5 further comprising a rectifier having its input connected to the alternator output and a storage capacitor connected to the output of the rectifier. 7. An electronic lock as claimed in claim 6 in which said electrically operated means comprises a lock release solenoid connected in series with a semi-conductor switch device across said storage capacitor- 8. An electronic lock as claimed in claim 7 further comprising a switchable stabilised supply for said el ctron¬ ic circuit, said supply being connected to draw current from said storage capacitor and being controlled by said semi-conductor switch device so as to cease drawing current when said semi-conductor switch device turns on. 9. An electronic lock as claimed in claim 8 in which said semi-conductor switch device is a thyristor. 10. An electronic lock as claimed in claim 2 in which said electronic circuit comprises key code reading means and ke r code storage means for storing the or each accept¬ able code. 11. An electronic lock as claimed in claim 10 in which said key-code reading means comprises an array of integra¬ ted hall-effect devices, the associated key- incorporating an array of correspondingly disposed magnets. 12. An electronic lock as claimed in claim 11 in which said ke r code storage means comprises a connection matrix connecting the outputs of said hall-effect devices to a gate circuit, whereby the gate circuit is activated only i the connections in the connection matrix match the outputs of the hall-effect devices.. comparator means connected to compare an output digital word from the key-code reading means with an output digital word from said storage means. 14. An electronic lock as claimed in claim 13 in which said comparator means includes multiplexing . means whereby a plurality of words from different groups of -reading elements in the key code reading means are compared successively with a plurality of words from corresponding different portions of said storage means-.

Inventors: CHEW I, VERHAEG J
Applicants: CHEW I, SCOVILL SECURITY PROD, VERHAEG J, SCOVILL SECURITY PROD LTD
Application year: 1981
Main classification: E05B49
IPC codes: E05B47, E05B49, G07C9