US3406386A - Chain lock alarm - Google Patents

Chain lock alarm Download PDF

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Publication number
US3406386A
US3406386A US492455A US49245565A US3406386A US 3406386 A US3406386 A US 3406386A US 492455 A US492455 A US 492455A US 49245565 A US49245565 A US 49245565A US 3406386 A US3406386 A US 3406386A
Authority
US
United States
Prior art keywords
alarm
chain
switch
housing
door
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US492455A
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English (en)
Inventor
Hawkins Paul Maddison
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Alarm Corp
Original Assignee
General Alarm Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by General Alarm Corp filed Critical General Alarm Corp
Priority to US492455A priority Critical patent/US3406386A/en
Priority to GB10255/66A priority patent/GB1081782A/en
Priority to DE19661553557 priority patent/DE1553557A1/de
Priority to CH1420366A priority patent/CH457180A/de
Application granted granted Critical
Publication of US3406386A publication Critical patent/US3406386A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • 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
    • E—FIXED CONSTRUCTIONS
    • E05—LOCKS; KEYS; WINDOW OR DOOR FITTINGS; SAFES
    • E05C—BOLTS OR FASTENING DEVICES FOR WINGS, SPECIALLY FOR DOORS OR WINDOWS
    • E05C17/00—Devices for holding wings open; Devices for limiting opening of wings or for holding wings open by a movable member extending between frame and wing; Braking devices, stops or buffers, combined therewith
    • E05C17/02—Devices for holding wings open; Devices for limiting opening of wings or for holding wings open by a movable member extending between frame and wing; Braking devices, stops or buffers, combined therewith by mechanical means
    • E05C17/04—Devices for holding wings open; Devices for limiting opening of wings or for holding wings open by a movable member extending between frame and wing; Braking devices, stops or buffers, combined therewith by mechanical means with a movable bar or equivalent member extending between frame and wing
    • E05C17/36—Devices for holding wings open; Devices for limiting opening of wings or for holding wings open by a movable member extending between frame and wing; Braking devices, stops or buffers, combined therewith by mechanical means with a movable bar or equivalent member extending between frame and wing comprising a flexible member, e.g. chains
    • E05C17/365—Security chains
    • 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
    • Y10T292/00—Closure fasteners
    • Y10T292/28—Extension link
    • Y10T292/283—Chain
    • 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
    • Y10T70/5164—Links to limit opening
    • 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

Definitions

  • This invention relates to a combined lock and alarm, and more particularly, to a lock of the type wherein a chain allows a door, for example, to swing open a limited distance relatively to its jamb, and means for sounding an alarm in the event that a given force is applied to the door while ajar to tension the chain, or in certain aspects of the invention, while the door is fully closed.
  • my invention contemplates a chain lock in combination with an alarm for use in connection with relatively moveable members such as a door and jamb, window and sash etc., comprising a flexible chain, means on one of said members for detachably mounting an end of the chain, and a normally open switch mounted on the other member, switch operating means moveable to actuate said switch to closed position, an alarm, electrical means such as a power source and appropriate circuitry are provided to operate the alarm when the switch is closed, and the chain is connected at its other end to the switch operating means whereby the chain shifts the operating means to switch closing position upon the application of a predetermined force to one of the members to move it relatively to the other.
  • chain is intended to include any flexible elongate member suitable for the intended purpose.
  • My invention also contemplates, in one aspect thereof, the inclusion of a dead bolt arranged to actuate the alarm when a predetermined force is exerted upon the door when it is fully closed and locked.
  • the alarm may be positioned near the door, or at any suitable remote location, and it may, of course, be of the visual or audible type, or both.
  • the switch operating means may be a lever mounted for pivotal movement against the force of an adjustable spring and formed with means for shifting the switch to closed position when such pivotal movement occurs.
  • the chain is connected to the lever and induces movement of same when under suflicient tension, and the spring is adjustable so as to vary the force required to actuate the alarm to suit the needs of each particular installation.
  • I utilize the housing to perform the function of the aforementioned lever by causing it to tilt against the force of a spring upon application of a predetermined force to the door.
  • the housing may also be utilized to actuate the alarm switch when an attempt is made to force or jimmy the door when same is dead locked.
  • lever or housing actuates the switch, but upon relaxation of the actuating force, the alarm continues even though the lever or housing returns to its original position under the influence of the spring. This is accomplished without the need of costly relays by forming the lever or housing with an opening so dimensioned as to engage a switch tab and close the switch during movement in one direction, but may shift back to its original position without engaging the tab. The alarm, once actuated, will thus remain in actuated condition until manually shut off.
  • Another important feature of my invention resides in the provision of a panic alarm and/or testing facility, whereby the operative condition of the alarm and its circuit components may be tested at will or an alarm sounded.
  • I provide a button mounted conveniently for manual depression to bypass the actuating switch and complete the alarm energizing circuit, thus advising of the condition of the power source, alarm mechanism and circuitry components or sounding an alarm.
  • the alarm actuating switch may be manually accessible for test purposes, in which case a separate test button and bypass circuit is unnecessary.
  • FIG. 1 is a view of the present lock and alarm combination as it may be used in connection with a door and jamb;
  • FIG. 2 is a front view of the alarm with the housing cover removed;
  • FIG. 3A is a side view of part of the switch operating mechanism in the olf position
  • FIG. 3B is a view similar to FIG. 3A but showing the parts in the on position
  • FIG. 4 is a side elevational view of another embodiment of my invention with some of the internal parts illustrated in broken lines, and shown in inactive position;
  • FIG. 5 is similar to FIG. 4, but shows the apparatus in active position
  • FIG. 6 is a plan view of the apparatus of FIGS. 4 and 5 without the chain;
  • FIGS. 7 and 8 are views similar to FIGS. 4 and 5 but illustrating the chain alarm system in combination with a dead bolt
  • FIG. 9 is a top view of the device of FIGS. 7 and 8 with the housing removed.
  • FIG. 1 there is shown a door 10 and jamb 11 in connection with which a preferred form of my invention may be put to use.
  • a plate 12 formed with an elongate T-shaped slot 14 shaped to receive at the juncture of its horizontal and vertical arms a grooved bolt or chain anchor 15 which may be positioned at the bottom of the vertical arm of the slot to keep taut the chain 13 to which it is attached, and thus keep the door closed; or the bolt may be positioned in the horizontal arm to permit the door to swing ajar a slight distance for identification of a caller while maintaining security.
  • the T-shape of the slot 14 allows the same plate 12 to be mounted on the jamb if desired or on left or right handed doors.
  • I mount on the jamb opposite the plate 12 a housing 16 comprising a back plate 17 and a cover 19 held to the back plate by a screw 20.
  • I provide an alarm 21 such as a conventional buzzer, bell or the like, and a battery 22 supported in clip 24.
  • the power circuit includes a single pole, single throw switch 25 with an operating handle 26 extending laterally thereof. Suitable wiring is provided to enable the battery source to energize the alarm when the switch is closed.
  • the alarm as a buzzer located in the housing, it can take the form of a flashing light, for example, and may be located remote from the lock, as for instance at a central guards office in the building, or at both locations. Where a remote alarm is employed, a miniature transmitter may be used in lieu of the wiring shown to signal the remote alarm.
  • switch operating means in the form of a lever 28 mounted in the housing 16 to pivot about pin 27.
  • the lever has a projection 29 formed with a hole 30 through which a screw 31 extends, the latter being threaded into a portion of the housing.
  • a compression spring 32 surrounds the screw and bears at one end against the projection 29 and at the other against the screw head so that clockwise pivotal movement of the lever, as viewed, is resisted by the spring.
  • the spring tension may be adjusted to the desired value by adjusting the screw 31.
  • the lever 28 is also formed with a square opening or hole 34, the sides of which embrace the switch handle 26; but when the parts are in their normal off position, the hole 34 and handle 26 are so related that the handle extends into the hole adjacent the left side thereof, as viewed in FIG. 3A.
  • the hole is actually of larger dimension than is necessary to embrace the handle 26, for a reason to be later described.
  • the side of the housing cover has an arcuate opening or hole 35 located between the pivot pin 27 and the hole 34- in lever 28.
  • a rivet or bolt 36 which is permanently affixed to the lever, extends through the opening 35 and an end of the chain 13 is attached to it.
  • the chain anchor 15 may be positioned in the vertical or horizontal arm of slot 14. If in the vertical arm of the slot, any attempt to open the door will place the chain 13 under tension; if in the horizontal arm of the slot, the door may be opened somewhat before the chain comes under tension. In any case, if a chain tensioning force is applied to the door to create a movement in the lever 28 sufficient to draw the latter from its off position (FIG. 3A) to the position shown in FIG. 3B, it will shift the switch handle 26 to the on position, thus actuating the alarm. Because the opening 34 is oversized and eccentric relatively to the handle 26, the switch will remain in the on position even if the chain tension is subsequently relaxed so. that the lever 28 returns to its original position.
  • the housing prevents a would-be intruder from interfering with operation of the alarm.
  • the screw 20 may be formed with a special head as shown in FIG. 1 so that ordinary screw drivers will not be effective for removal of the cover 19.
  • the tenant will, of course, be provided with a special key or screw driver for removing the cover to service the system.
  • the cover 19 may also have a circular opneing 39 (FIG. 1) for mounting the chain anchor 15 when the door is'opened wide.
  • a push button 37 which projects out of the bot tom of the housing 16. When depressed, the button simply grounds the negative side of the battery 22 to the housing to complete the circuit to the alarm which is also grounded to the housing. The button 37 thus effectively bypasses the switch 25.
  • FIG. 4 I show a further embodiment of the invention according to which the chain 13 is secured to a decorative anchor 40 mounted on the door panel or jamb 11, while the housing 41 is mounted on a base plate 42 secured to the door 10.
  • the edge of the housing 41 adjacent the plate 42 is relieved slightly at the right hand side, as viewed, so that the relieved portion 44 of edge is normally slightly angulatcd relatively to the surface of the plate.
  • the housing is secured to the plate 42 by a screw 47 that extends down through a cylindrical recess 49 formed in the housing, and into the plate 42.
  • a spring 50 bears against the bottom of the recess. and against the head of the screw to bias the housing into the position shown in FIG. 4.
  • one end of the chain 13 is secured to the anchor 40.
  • the other end of the chain is connected to a chain anchor 45 adapted to enter a chain anchor slot 46 (FIG. 6) at its large end and slide lengthwise in its slot to allow for partial opening of the door while retaining chain security.
  • a similar hole 48 has a shortened slot and may accept the chain anchor 45 without allowing for partial opening of the door.
  • the housing 41 has a slot 51 formed in one of its sides through which slot a switch handle 52 (similar to handle 26 of FIGS. 2, 3A and 3B) extends, and an alarm 53 and one or more batteries 22 may be contained within the housing. It will be understood that, as in the previously described embodiment, the power source and alarm may be remotely located. A simple series circuit (not shown) is arranged to supply power from the batteries to the alarm when the switch 54 is closed.
  • the chain is set as shown in FIG. 4 and is, of course, of sufficient length so that the door may be opened somewhat without actuating the alarm. How ever, if the door is opened and then forced beyond a predetermined limit, the chain serves to rock the housing 41 about the point of juncture of the plane of the relieved portion 44 with the plane of remainder of the inner edge of the housing. Thus, this point of juncture becomes a fulcrum about which the housing rocks to the position shown in FIG. 5.
  • the spring 50 resists this movement and may be adjusted by means of the screw 47, to increase or decrease the load necessary to be overcome in order to rock the housing. The housing moves to the position of FIG.
  • a holding relay could be used to maintain the alarm circuit closed, but I find the described system simple and inexpensive.
  • the switch may be thrown to closed position at any time to test the circuit and power supply or sound a panic alarm. If the chain anchor 45 is positioned in hold 48, the same switch actuation will occur upon application of force against the door when in fully closed position.
  • the chain may be encased in a sleeve of leather or plastic, for example, and the housing may be formed so that the chain anchor slot 46 is at the bottom of a groove of a depth whereby the chain will be flush with the surface of the housing.
  • FIGS. 7 to 9 A further embodiment of my invention is shown in FIGS. 7 to 9 wherein the chain lock and alarm are substantially identical to those already described in connection with FIGS. 4 to 6.
  • the housing 60 and strike plate 61 are larger than those described so that the former'can house, in addition to the alarm unit, batteries and switch, a dead bolt lock mechanism identified generally by the numeral 62 in FIG. 9, and the latter becomes a keeper for a dead bolt.
  • This lock mechanism 62 is conventional and comprises briefly, a rotatable crank 64 pivoted to a connecting arm 65 that is in turn pivotally connected at 66 to a dead bolt 67.
  • the crank 64 can swing only 180 between bolt retracting and projecting positions, its limits of movement being defined by stops 69.
  • a torsion spring 70 having one end anchored to the arm 65 and the other to a relatively stationary member, provides a toggle action to movements of the bolt.
  • the crank is manually actuated from inside the door by a thumb turn 71 (FIGS. 7 and 8) and from outside the door by a key operated lock cylinder 72.
  • I have arranged for the provision, where desired, of a bolt condition indicator which may constitute a simple flag moveable with the thumb turn or lock cylinder to indicate bolt condition.
  • a bolt condition indicator which may constitute a simple flag moveable with the thumb turn or lock cylinder to indicate bolt condition.
  • I prefer to utilize an electric lamp which is lighted when the bolt 67 is retracted.
  • I provide a lamp 86 beneath a viewing opening in the keeper 61 and within the keeper I locate a switch 87 such as a microswitch operable when the bolt is thrown to protracted position to open a series circuit which includes a battery 89, thus to deenergize the lamp.
  • the switch closes to energize the lamp, thus indicating the retracted condition of the bolt.
  • house power may be used if desired in lieu of the battery 89.
  • a viewing opening may be located on the opposite side of the lamp 86 so that the bolt condition will be observable from the exterior of the door.
  • housing and keeper may be mortised into the door and jamb rather than surface mounted.
  • a further feature of my invention resides in the provision of a key lock-out device which operates to prevent 6 unlocking of the lock from outside whenever the chain anchor 91 (FIG. 7) is slid forward in its slot 90 (FIG. 9) to engage the thumb-turn 71 (FIG. 8).
  • the chain anchor 91 is engaged in the anchor slot 90 and can be so positioned, as shown in its dotted outlined position, to engage a slot 92 (FIG. 8) in the thumb-turn 71 when the thumb-turn is turned to its locked position as shown in FIG. 7. This prevents retraction of the dead bolt by any means until the chain anchor 91 is first removed from the slot 92 of the thumb-turn 71.
  • achain lock having a key lock out feature comprising a lock adapted to be mounted on one side of a door with a thu mb-tur-n on said one side for manipulating said lock and means adapted to be engaged by a key from the opposite side of 'said door also for manipulating said lock with consequent turning of said thumb-turn, a flexible chain, means forattaching one end of said chain securely to a door casing, a chain anchor attached to the opposite end of said chain, guide means on said lock for securing said chain anchor to said lock and for allowing limited sliding movement of said chain anchor on said lock, and means associated with said chain anchor for engaging said thumb-turn and preventing its rotation when said chain anchor is moved to a given position on said lock.
  • a chain lock-alarm dCViCeCOmPIiSiHg in combination, a flexible chain, means for securing one end of said chain to one of two relatively movable members, a housing, means for securing the other end of said chain to said housing, means for mounting said housing to the other of said members in a manner permitting limited movement of said housing on said other member inresponse to tension in said chain when said members are forced toward a mutually separated condition, spring means arranged to bias said housing against said limited movement of said housing, and an alarm actuating switch enclosed by said housing, said switch including a switch arm arranged such that movements of said housing caused by excessive tension on said chain operates 'said switch to an alarm actuating condition.
  • a chain lock-alarm device as in claim 9..wherein there is provided an alarm within said housing-and arrangedto be actuated by operation'ot said alarm actuating switch. 1 1 13.. A chain lock-alarm device as in claim 9 wherein there is provided in said'housing a test switch connected in parallel-with said alarm actuating switch.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Burglar Alarm Systems (AREA)
US492455A 1965-10-04 1965-10-04 Chain lock alarm Expired - Lifetime US3406386A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US492455A US3406386A (en) 1965-10-04 1965-10-04 Chain lock alarm
GB10255/66A GB1081782A (en) 1965-10-04 1966-03-09 Improvements in apparatus for actuating an alarm upon movement of a closure member relative to a stationary member
DE19661553557 DE1553557A1 (de) 1965-10-04 1966-05-02 Mit einer Alarmeinrichtung kombiniertes Kettenschloss
CH1420366A CH457180A (de) 1965-10-04 1966-09-30 Kettenschloss mit Alarmeinrichtung

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US492455A US3406386A (en) 1965-10-04 1965-10-04 Chain lock alarm

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US3406386A true US3406386A (en) 1968-10-15

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US492455A Expired - Lifetime US3406386A (en) 1965-10-04 1965-10-04 Chain lock alarm

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US (1) US3406386A (de)
CH (1) CH457180A (de)
DE (1) DE1553557A1 (de)
GB (1) GB1081782A (de)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3623062A (en) * 1970-06-25 1971-11-23 Minnesota Mining & Mfg Lock alarm structure
US3643250A (en) * 1970-12-08 1972-02-15 Paul F Sander Theft deterrent for office machines and small factory tools
USD252850S (en) 1977-06-29 1979-09-11 Jorgensen Deceased Clarence W Burglar alarm
US5097253A (en) * 1989-01-06 1992-03-17 Battelle Memorial Institute Electronic security device
US5296841A (en) * 1992-09-21 1994-03-22 Alan Vormbrock Chain guard alarm apparatus
US5469139A (en) * 1995-02-16 1995-11-21 Ko; Joseph Y. Door block alarm
US6049276A (en) * 1998-03-02 2000-04-11 Agozzino; Andrew Burglar chain alarm
EP0942128A3 (de) * 1998-03-12 2002-02-06 Robert Bosch Gmbh Einrichtung für eine Einbruchmeldeanlage
US7847689B1 (en) * 2008-01-03 2010-12-07 Larry Woitalla Intruder alarm device
US10443267B2 (en) 2015-05-04 2019-10-15 Spectrum Brands, Inc. Lockset with cylinder integrity sensor

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2462872C2 (de) * 1974-12-11 1984-01-26 Fa. Aug. Winkhaus, 4404 Telgte Alarmauslösende Verriegelungseinrichtung
DE102008013685A1 (de) * 2008-03-11 2009-09-24 Bothe-Hild Gmbh Sicherungsvorrichtung für ein Tor sowie Sicherungsverfahren

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1156809A (en) * 1915-03-17 1915-10-12 Thomas L Pidgeon Burglar-alarm bolt.
US1157863A (en) * 1914-06-29 1915-10-26 Hamlau S Patents Company Combined burglar-alarm and lock.
GB636985A (en) * 1939-05-03 1950-05-10 Daniel Georg Martens An electric alarm device in connection with safety-chains for doors
US2818475A (en) * 1957-05-17 1957-12-31 Harry Frank Automatic alarm lock

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1157863A (en) * 1914-06-29 1915-10-26 Hamlau S Patents Company Combined burglar-alarm and lock.
US1156809A (en) * 1915-03-17 1915-10-12 Thomas L Pidgeon Burglar-alarm bolt.
GB636985A (en) * 1939-05-03 1950-05-10 Daniel Georg Martens An electric alarm device in connection with safety-chains for doors
US2818475A (en) * 1957-05-17 1957-12-31 Harry Frank Automatic alarm lock

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3623062A (en) * 1970-06-25 1971-11-23 Minnesota Mining & Mfg Lock alarm structure
US3643250A (en) * 1970-12-08 1972-02-15 Paul F Sander Theft deterrent for office machines and small factory tools
USD252850S (en) 1977-06-29 1979-09-11 Jorgensen Deceased Clarence W Burglar alarm
US5097253A (en) * 1989-01-06 1992-03-17 Battelle Memorial Institute Electronic security device
US5296841A (en) * 1992-09-21 1994-03-22 Alan Vormbrock Chain guard alarm apparatus
US5469139A (en) * 1995-02-16 1995-11-21 Ko; Joseph Y. Door block alarm
US6049276A (en) * 1998-03-02 2000-04-11 Agozzino; Andrew Burglar chain alarm
EP0942128A3 (de) * 1998-03-12 2002-02-06 Robert Bosch Gmbh Einrichtung für eine Einbruchmeldeanlage
US7847689B1 (en) * 2008-01-03 2010-12-07 Larry Woitalla Intruder alarm device
US10443267B2 (en) 2015-05-04 2019-10-15 Spectrum Brands, Inc. Lockset with cylinder integrity sensor

Also Published As

Publication number Publication date
GB1081782A (en) 1967-08-31
CH457180A (de) 1968-05-31
DE1553557A1 (de) 1969-06-19

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