US3800572A - Safety device for a lock and a lock including said device - Google Patents

Safety device for a lock and a lock including said device Download PDF

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Publication number
US3800572A
US3800572A US00336814A US3800572DA US3800572A US 3800572 A US3800572 A US 3800572A US 00336814 A US00336814 A US 00336814A US 3800572D A US3800572D A US 3800572DA US 3800572 A US3800572 A US 3800572A
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United States
Prior art keywords
bolt
lock
keeper
recess
displacement
Prior art date
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Expired - Lifetime
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US00336814A
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English (en)
Inventor
B Beharelle
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Individual
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Individual
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Classifications

    • E—FIXED CONSTRUCTIONS
    • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
    • E05B—LOCKS; ACCESSORIES THEREFOR; HANDCUFFS
    • E05B47/00—Operating or controlling locks or other fastening devices by electric or magnetic means
    • E05B47/06—Controlling mechanically-operated bolts by electro-magnetically-operated detents
    • E05B47/0603—Controlling mechanically-operated bolts by electro-magnetically-operated detents the detent moving rectilinearly
    • E—FIXED CONSTRUCTIONS
    • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
    • E05B—LOCKS; ACCESSORIES THEREFOR; HANDCUFFS
    • E05B45/00—Alarm locks
    • E05B45/06—Electric alarm locks
    • E05B45/08—Electric alarm locks with contact making inside the lock or in the striking plate
    • E05B45/083—Electric alarm locks with contact making inside the lock or in the striking plate with contact making either in the striking plate or by movement of the bolt relative to the striking plate
    • E—FIXED CONSTRUCTIONS
    • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
    • E05B—LOCKS; ACCESSORIES THEREFOR; HANDCUFFS
    • E05B15/00—Other details of locks; Parts for engagement by bolts of fastening devices
    • E05B15/16—Use of special materials for parts of locks
    • E05B15/1614—Use of special materials for parts of locks of hard materials, to prevent drilling
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T70/00—Locks
    • Y10T70/50—Special application
    • Y10T70/5093—For closures
    • Y10T70/5155—Door
    • Y10T70/5199—Swinging door
    • Y10T70/5246—Dead bolts
    • Y10T70/5296—Single
    • Y10T70/5319—Sliding
    • Y10T70/5341—Key operable only
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T70/00—Locks
    • Y10T70/70—Operating mechanism
    • Y10T70/7006—Predetermined time interval controlled
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T70/00—Locks
    • Y10T70/70—Operating mechanism
    • Y10T70/7441—Key
    • Y10T70/7915—Tampering prevention or attack defeating
    • Y10T70/7932—Anti-pick

Definitions

  • ABSTRACT For a lock comprising a bolt, a keeper in which the bolt is engagcable in the closing position of thelock and means for shifting the bolt.
  • the safety device comprises delayed-action means for blocking the bolt and precluding displacement of the bolt in the direction for opening the lock a predetermined interval of 7 time after the bolt has been displaced an initial partial distance in the direction for opening the lock by the shifting means.
  • the present invention relates to locks and more particularly to safety devices for locks adapted to prevent the opening of the lock by means other than the key provided for normal operation of the lock.
  • a premises thus protected may be entered with no subsequent visible sign of breaking in.
  • An object of the present invention is to overcome the aforementioned drawbacks and provide a safety device for a lock which renders the opening or unlocking of the lock impossible by means other than the key intended for actuating the lock.
  • the invention provides a safety device for a lock comprising a bolt, a keeper in which the bolt is engaged in the closing position of the lock and bolt actuating means, wherein delayed-action blocking means prevent displacement of the bolt in the direction for opening Now, the delayed-action blocking means are adapted,
  • FIG. 1 is an elevational view, with parts cut away, of a lock provided with a safety device according to the invention, an alarm actuating device being furthermore mounted in the keeper;
  • FIG. 2 is a partial elevational view, with parts cut away, of the lock shown in FIG. 1 and illustrating the action ofthe bolt blocking means;
  • FIG. 3 is a perspective view of electromagnetic means of a time delay means which are part of the delayed-action blocking means of the safety device shown in FIG. 1;
  • FIG. 4 is a circuit diagram of the time delay circuit of the safety device shown in FIG. 1-3;
  • FIG. 5 is an elevational view, with parts cut away, of a lock provided with another embodiment of the safety device according to the invention.
  • FIG. 6 is a sectional view, taken on line 6-6 of FIG. 1, showing the alarm actuating device incorporated in the keeper of the lock.
  • the invention has-been illustrated as being applied to a barrel-type'lock.
  • This lock comprises, housed in a case 1 which is preferably of hard steel, such as Z 200 C 12 steel, so as to render the interior of the lock inaccessible by drilling, a bolt 2 which is normally shiftable by a barrel-type mechanism with the aid of a key (not shown).
  • a case 1 which is preferably of hard steel, such as Z 200 C 12 steel, so as to render the interior of the lock inaccessible by drilling, a bolt 2 which is normally shiftable by a barrel-type mechanism with the aid of a key (not shown).
  • the barrel 3 is advantageously protected against any attempt to drill by a protecting sleeve 4 also of hard steel.
  • the sleeve 4 has at one end a flange fixed to the case I, for example by welding.
  • the sleeve 4 has an end wall provided with an eccentric aperture 7 closed by a disc or block 8 of hard steel which is provided with a slot 9 for the passage of the key and is rotatably mounted in the aperture 7 by means of a boss. 7
  • the bolt 2 is adapted to co-operate with a keeper 10 provided with an alarm actuating device which will be described hereinafter.
  • the bolt 2 is provided, substantially midway along its length, with a recess 11 formed in its upper-part and having a vertical lateral wall 12 and an inclined wall 13 constituting a ramp.
  • a delayed-action blocking or stop means Disposed in a housing 14 of the case 1 above the bolt 2 is a delayed-action blocking or stop means for stopping displacement of the bolt.
  • This device comprises a block 15 of plastics material havinga transverse aperture 16 in which is disposed a finger member 17 which is of magnetic material and biased in the direction of the bolt 2 by a spring 18.
  • Embedded in the block 15 is a magnetic circuit constituted by a flat magnet 19 (FIG. 3) against the poles of which are applied two elongated pole pieces 20 and 21 which are electrically insulated from the magnet by thin films 22 and 23 of insulating material, for example varnish.
  • the magnet may be constituted by a block of plastics material having a charge of particles of magnetic material.
  • a magnet is practically non-conductive of-electricity and the films of insulating material between its poles and the pole pieces are superfluous.
  • the pole pieces 20 and 21 respectively carry demagnetizing windings 24 and 25 the coils of which have opposite directions of windings.
  • the ends of the pole pieces opposed to the magnet 19 are separated from each other by a block 26 ofinsulating material and constitute with the latter a recess in the shape of a portion of a cylinder 27 whose diameter is the same as the diameter of the aperture 16, the surface of the recess being flush with the surface of the aperture 16.
  • the windings 24 and 25 are respectively connected by one of their terminals to the pole pieces 22 and 23 each of which carries a connector 28, 29.
  • the conductors 30 and 31 for connection to a time delay circuit 32 are fixed to the connectors 28, 29.
  • windings 24 and 25 are connected to a common connector '33 which is insulated from the pole pieces 20 and 21 and to which is secured another conductor 34 for connection to the time delay circuit.
  • the finger member 17 and the recessed ends of the pole pieces 20, 21 constitute a switch, the closure of which achieved simultaneously with the closure of the magnetic circuit formed by the magnet 19, the pole pieces 20 and 21 and the finger member 17 causes the connection in parallel of the windings 24 and 25 between the conductors 29 and 30, on one hand, and the conductor 33 on the other.
  • the windings 24 and 25 are supplied with current by the time delay circuit 31 from a source of dc voltage, as a dry battery 35, disposed in the right part of the case 1.
  • the time delay circuit 32 is actuated by a microswitch 36 fixed to the lower part of the block containing the electromagnetic device for maintaining the finger member 17 for blocking the bolt 2.
  • the pushmember of this switch co-operates with a plate 37 whichconstitutes a cam and is secured to the lateral wall of the bolt by screws 38 in such position that the switch 36 is actuated when the recess 11 of the bolt is located in alignment with the finger member 17.
  • FIG. 4 shows the circuit diagram of the time delay circuit 32 and the electromagnetic device for maintaining the finger member 17 in position.
  • This circuit supplied with current by the battery 35 shown in FIG. 1, essentially comprises a transistor 40 the base of which is connected to the negative terminal of the battery through a Zener diode 41, two fixed resistors 42, 43 and a variable resistor 44 connected in series.
  • the junction between the Zener diode 41 and the re sistor 42 is connected to the positive terminal of the battery 35 through a capacitor 45 and a resistor 46 connected in parallel.
  • the collector of the transistor 40 is connected to the common terminal of the windings 24 and through the conductor 34 shown in FIG. 3 and its emitter is connected to the positive terminal of the battery 35 through a switch formed by the pole pieces 20 and 21 and the finger member 17, the connections being ensured by the conductors and 31 shown in FIG. 3.
  • the negative terminal of the capacitor 45 is connected to the positive terminal of the battery through the microswitch 36 which is actuated by the cam 37 integral with the bolt 2.
  • the bolt shown in FIG. 5 is equipped with a safety de vice of different design to that of the safety device shown in the lock illustrated in FIG. 1.
  • This safety device comprises a small air cylinder device 47 disposed in the housing 14a provided in the upper part of the case la of the lock.
  • a piston 49 biased in the direction of the bolt 2a of the lock by a spring 50, a sealing ring 51 ensuring a fiuidtight connection between the piston and the wall of the cylinder.
  • the piston carries in its lower part a rod 52 which extends out of the cylinder device and constitutes a finger member for blocking or stopping the bolt 2av
  • a sealing ring 53 ensures a fluidtight connection be tween the rod 52 and the wall of the cylinder device through which the rod extends.
  • the part of the cylinder 48 located on the side of the piston adjacent the rod 52 communicates with the exterior by way of an air inlet and outlet orifice 54 the section of which is adjustable by a needle valve screw 55 and the part of the cylinder adjacent the spring communicates with the exterior by way of an orifice 56.
  • the bolt 2a has a recess 11a similar to the recess 11 ofthe bolt ofthe lock shown in FIG. 2. However, in addition to the vertical wall 12a and inclined wall 13a, this recess 11a has an additional recess 57 adapted to ensure that the rod 52 does not block or stop displacement of the bolt immediately after the recess 11a has been placed in front of the rod 52 so that the lock can be opened normally by means of the key provided for this purpose.
  • the recess 11 is in alignment with the finger member 17 and the cam 37 actuates the microswitch 36, the opening of which connects the capacitor to the terminals of the battery 35 (FIG. 4) through the resistors 42, 43, 44.
  • the capacitor starts to charge, its time constant being regulated to a given value by means of the variable resistor 44.
  • the finger member 17 is no longer bearing against the bolt 2 but, bearing in mind that the force of the spring 18 is calculated in such manner as to be incapable of overcoming the force of attraction of the finger member 17 by the pole pieces 20 and 21, the finger member is maintained in its upper position so long as the windings 24 and 25 do not carry current.
  • the penetration of the finger member 17 in the recess 11 cuts one of the connections between the windings 24 and 25 and the connection between the emitter of the transistor and the positive terminal of the battery 35,.which reduces the consumption of the device.
  • the rod 52 of the piston 49 is maintained in its upper position by the upper wall of the bolt 2a.
  • the recess 11a of the bolt is brought by the first rotation of the key in alignment with the rod 53.
  • the piston expelling the air contained in the lower part of the cylinder by way of the orifice 54.
  • the section of the orifice 54 is so adjusted by means ofthe needle valve 55 that the rod cannot reach a level lower than the depth of the recess 57 before the user has given the second rotation to the key so that, in the course of the second displacement of the bolt, the rod 53 is raised to its initial position by hearing in the recess 57.
  • the safety devices shown in FIGS. 1 and 5 are both adjusted in such a manner that their time delay, respec-
  • the alarm actuating device shown in FIG. 6 is asso- I ciated with the keeper 10 of the lock.
  • the invention provides a device which is responsive to such a thrust and is adapted to actuate an alarm bell.
  • the free space defined in the keeper 10 is employed for enclosing a first plate 60 of insulating material which is applied against the inner wall of the keeper l0 opposite itsplane of application against the frame 61 of the door.
  • the plate 60 is supported by this inner wall-of the keeper 10 through two springs 62 engaged in blind apertures 63 provided in the plate and defines on its face opposed to the apertures 63 a recess 64 adapted to allow the passage of the bolt 2 of the lock.
  • a second plate 65 of insulating material defines a recess 66 disposed in front of the recess 64 formed in the plate 60 with which it is assembled by means of screws 67 of the keeper 10 which also act as guides for displacement of the plate 60.
  • the recesses 64 and 66 of the plates 60 and 65 constitute a cavity in which the bolt 2 penetrates.
  • microswitches 68 and 69 Embedded in the plate 65 are two microswitches 68 and 69 which are disposed on each side of the recess 66. The push-members of the microswitches are in contact with the surface of the plate 60.
  • the switches 68 and 69 are connected in parallel through conductors 70 and 71 embedded in the plate 65' and conductors 72 and 73 to an alarm hell (not shown) and to its source of power.
  • a thrust exerted on the door causes the displacement of the plate 60 by the bolt 2 in opposition to the action of the springs 62 and 63.
  • the push-members of the switches 68 and 69 which are normally open, are then released owing to the fact that the distance between the plate 60 and the plate 65 is increased and this closes the switches and causes actuation of the alarm bell.
  • the bell may be supplied with power either by the mains or by an independent source of voltage, forexample a, battery.
  • the safety device shown in FIGS. 1-5 is compact so that it is adaptable to a large number of existing locks. Further, the safety device shown in FIG. 5 is equipped with an air cylinder device 47, but it is possible to employ for actuating the bolt blocking rod a hydraulic cylinder device whose piston integral with the rod is biased in the direction of the bolt of the lock by a spring. in the case of a hydraulic cylinder device,the cylinder ofthe device is hermetically closed.
  • the piston of the cylinder device defines two chambers in the cylinder, these chambers communicating by way of'a calibrated orifice formed in the piston so that, in the course of the displacement of the piston under the action of the spring, the passage of oil from one chamber to the other by way of the orifice displaces the blocking rod at a given speed and thus affords the time delay for blocking the bolt.
  • the device for actuating an alarm is adaptable to all locks which have a keeper the internal volume of which is sufficient to house the device. 7
  • the safety device according to the invention renders a lock with which it is equipped practically unpickable.
  • the lock when the case of the lock is constructed from hardened steel, and, if it concerns a barrel-type lock, the barrel is protected by the arrangement described with reference to FIG. 1, the lock is rendered practically inaccessible by picking or drilling.
  • a safety device for a lock comprising a case, a bolt, a keeper in which the bolt is engageable in a closing position of the lock, bolt shifting means associated with the bolt to shift the bolt a given distance out of engagement with the keeper, delayed-action blocking means for precluding displacement of the bolt in a direction for opening the lock after a predetermined interval of timeand means for associating the blocking means with the bolt so that the blocking means are rendered operative by a displacement of the bolt through an initial part of said given distance by said shifting means.
  • a safety device for a lock comprising a case, a bolt, a keeper in which the bolt is engageable in a closing position of the lock, bolt shifting means associated with the bolt to shift the bolt a given distance out of engagement with the keeper, delayed-action blocking means for precluding displacement of the bolt in a direction for opening the lock after a predetermined interval of time, the blocking means comprising a recess in the bolt, a finger member which is mounted relative to the case to move transversely of the direction of displacement of the bolt between the first position out of engagement with the recess and a second position of engagement with the recess when the bolt has been displaced through an initial part of said given distance by the shifting means, an electromagnetic device associated with the finger member for maintaining the finger member out of engagement with the recess, means for ordinarily biasing the finger member to said second position, a time delay circuit associated with the electromagnetic device to cause the electromagnetic device to release the finger member after a predetermined time interval and means for bringing the time delay circuit into action when the bolt has been
  • a device as claimed in claim 2 comprising a block of plastics material mounted in the case, means defining an aperture in the block, the finger member being slidably mounted in the aperture, the means for biasing the finger member being a spring bearing against the finger member, the electromagnetic device being embedded in he block.
  • the electromagnetic device comprises a magnet having poles, two elongate pole pieces having first end portions applied against the poles of the magnet, means for insulating said end portions from the magnet, a demagnetizing winding carried by each pole piece and connected to the time delay circuit, the pole pieces having second end portions which are insulated from each other and define faces which constitute movable parts of a wall defining said aperture.
  • a safety device as claimed in claim 2, wherein said means for bringing the time delay circuit into action comprise a switch having a push-member and a cam fixed to the bolt and capable of shifting the pushmember of the switch.
  • a safety device as claimed in claim 6, wherein the time delay circuit comprises a transistor, said demagnetizing windings being connected to the emittercollector terminals of the transistor through said switch constituted by the pole pieces and the finger member,
  • a safety device for a lock comprising a case, a bolt, a keeper in which the bolt is engageable in a closing position of the lock, bolt shifting means associated with the bolt to shift the bolt a given distance out of engagement with the keeper, delayed-action blocking means for precluding displacement of the bolt in a direction for opening the lock after a predetermined interval of time, the blocking means comprising a recess in the bolt, a cylinder device having a cylinder and a piston slidable in the cylinder, a rod integral with the piston and movable transversely of the direction of displacement of the bolt between a first position out of engagement with the recess and a second position of engagement with the recess when the bolt has been displaced through an initial part of said given distance by the shifting means, resiliently yieldable means associated with the piston to bias the piston in the cylinder of the cylinder device in a direction to move the rod to said second position, the cylinder'device comprising means for adjusting the rate of discharge of the fluid displaced by the piston
  • a lock comprising a case, a bolt movable in the case, a keeper in which the bolt is engageable in a closing position of the lock, bolt shifting means associated with the bolt to shift the bolt a given distance out of engagement with the keeper, and a safety device comprising delayed-action blocking means for precluding displacement of the bolt in a direction for opening the lock after a predetermined interval of.time and means for associating the blocking means with the bolt so that "the blocking means-are rendered operative by a disdefining a slot for the introduction of a key for actuating the lock.
  • each of said plates defines a recess, said recesses constituting a cavity for receiving the bolt of the lock.

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  • Lock And Its Accessories (AREA)
US00336814A 1972-03-03 1973-02-28 Safety device for a lock and a lock including said device Expired - Lifetime US3800572A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR7207553A FR2174438A5 (enExample) 1972-03-03 1972-03-03

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US3800572A true US3800572A (en) 1974-04-02

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US00336814A Expired - Lifetime US3800572A (en) 1972-03-03 1973-02-28 Safety device for a lock and a lock including said device

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US (1) US3800572A (enExample)
DE (1) DE2310612A1 (enExample)
FR (1) FR2174438A5 (enExample)
IT (1) IT981030B (enExample)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4640110A (en) * 1985-09-16 1987-02-03 Ilco Unican Corp. Automatic delay relocking device
US4712398A (en) * 1986-03-21 1987-12-15 Emhart Industries, Inc. Electronic locking system and key therefor
US4848115A (en) * 1986-03-21 1989-07-18 Emhart Industries, Inc. Electronic locking system and key therefor
US4850623A (en) * 1983-05-12 1989-07-25 Chubb & Son's Lock And Safe Co., Ltd. Locking mechanisms
DE4404914A1 (de) * 1994-02-16 1995-08-17 Winkhaus Fa August Sperrmechanismus für ein Schloß
USD496247S1 (en) 2003-05-16 2004-09-21 Richard F. Roach Safety lock for seat belt buckle
US20230399873A1 (en) * 2019-04-05 2023-12-14 Dormakaba Usa Inc Electronic lock

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3207910C2 (de) * 1982-03-05 1985-10-17 Recke, Manfred, 7410 Reutlingen Schließeinrichtung
DE3372390D1 (en) * 1982-10-28 1987-08-13 Terry P A Security Consult Lever lock safety device
EP0798435A1 (fr) * 1996-03-27 1997-10-01 Guy Prieur Gâche alarme

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2318908A (en) * 1941-03-08 1943-05-11 American Hardware Corp Lock

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2318908A (en) * 1941-03-08 1943-05-11 American Hardware Corp Lock

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4850623A (en) * 1983-05-12 1989-07-25 Chubb & Son's Lock And Safe Co., Ltd. Locking mechanisms
US4640110A (en) * 1985-09-16 1987-02-03 Ilco Unican Corp. Automatic delay relocking device
US4712398A (en) * 1986-03-21 1987-12-15 Emhart Industries, Inc. Electronic locking system and key therefor
US4848115A (en) * 1986-03-21 1989-07-18 Emhart Industries, Inc. Electronic locking system and key therefor
DE4404914A1 (de) * 1994-02-16 1995-08-17 Winkhaus Fa August Sperrmechanismus für ein Schloß
USD496247S1 (en) 2003-05-16 2004-09-21 Richard F. Roach Safety lock for seat belt buckle
US20230399873A1 (en) * 2019-04-05 2023-12-14 Dormakaba Usa Inc Electronic lock

Also Published As

Publication number Publication date
FR2174438A5 (enExample) 1973-10-12
IT981030B (it) 1974-10-10
DE2310612A1 (de) 1973-09-06

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