US2824300A - Closure alarm device - Google Patents

Description

. Feb. 18, 1958 s. RAND 2,824,300

CLOSURE ALARM DEVICE Filed July 11, 1956 United States Patent CLOSURE ALARM DEVICE Samuel Rand, New Orleans, La. Application July 11, 1956, Serial No. 597,210

7 Claims. (Cl. 340-274) closures such as doors, windows and the like.

Another object of the present invention is the provision of novel burglar alarm apparatus useful in conjunction with fire alarms of the type having an exposed bimetallic contact arm for actuating the bimetallic contact arm to energize the fire alarm in response to movement of a closure or closure fastener.

Another object of the present invention is the provision of novel means in association with a fire alarm of the type having an exposed bimetallic contact arm in the alarmenergizing circuit for actuating the contact arm to energize the alarm upon opening movement of a door, drawbolt or the like, located adjacent the alarm, and wherein said means may be deactivated during selected periods, rendering the alarm nonresponsive to manipulation of the door, drawbolt or the like.

Another object of the present invention is the provision of a facility rendering fire alarms additionally operative as burglar alarms responsive to surreptitious manipulation of closures and closure fasteners, which facility is of exceedingly simple and inexpensive construction and is durable anddependable in operation.

Other objects, advantages andcapabilities of the present invention will become apparent from the following detail description, taken in conjunction with the accompanying drawing, illustrating two preferred embodiments of the invention.

In the drawing;

Figure 1 is a front elevation of an embodiment of the present invention arranged in operative relation with a door and door opening;

Figure 2 is a side elevation of the embodiment illustrated in Figure 1, wherein the position of the components in their released state to actuate the alarm in response to the opening movement of the door is illustrated in dotted ines;

Figure 3 is a front elevation of a second embodiment of the present invention wherein a modified drawbolt unit serves as the alarm actuator; and

Figure 4 is an exploded fragmentary perspective view of the modified drawbolt and drawbolt keeper of the second embodiment of the present invention.

Referring to the drawing wherein like reference characters designate corresponding parts throughout the several figures, particular reference being had to Figures 1 and '2, the burglar alarm attachment of the present invention, generally indicated by the reference character 10, is adapted to be associated with a conventional. portable fire alarm unit 11 of the type adapted for ready installation in homes, buildings and the like, and having an exposed bimetallic contact as illustrated in the figures of 2,824,300 Patented Feb. 18, 1958 the drawing, the burglar alarm attachment 10 and portable fire alarm unit 11 are designed to be readily aifixed to a door jamb member 12 adjacent the door opening in a manner to render these components responsive to actuation upon surreptitious operation of the door 1-3.

The portable fire alarm unit 11 illustrated in the drawing is of a conventional type which is readily available on the market. The exemplary preferred fire alarm unit 11 illustrated in the drawing includes a backing panel 14 of electrically conductive metallic material which is adapted to be removably secured against a building wall surface such as the door. jamb 12 which supports an alarm member 15 and a pair of outwardly projecting vertically spaced brackets 16, 17 for supporting a pair of dry cell batteries 18. The alarm member 15 may comprise any well known sound emission device capable of energization by an electric current, such as an electric hell on an electric buzzer, the latter of which is illustrated in Figures 1-3. The upper bracket 16 carries a bifurcated electrically conductive contact member 19 having depending recurved contact legs 20 adapted to engage the central carbon electrode cap of one of the batteries 18 and the bottom of the battery cup electrode of the other battery 18, the bifurcated contact member being supported or being insulated from the upper bracket 16, and the lower bracket 17 carries a pair of laterally spaced fixed contacts 21 and 22 each of which is insulated from and projects through the bracket 17 to contact the central electrode cap of one battery 18 and the bottom of the electrode cup of the other battery 18. By this arrangement, the batteries when received between the contacts supported on the brackets 16, 17 with the batteries arranged side-byside but inverted relative to each other, will be arranged in pairs between the contacts 21 and 22. The recurved contact legs 20 are preferably in the nature of leaf spring members to frictionally retain the batteries 18 in position between the contacts.

One of the contacts 21 is preferably connected by means of conductor 23 to one pole of the alarm member 15. The other pole of the alarm member 15 is grounded to the backing panel 14, and a bimetallic arm 24 is preferably supported at one end, as indicated at 25, in exposed position below the lower battery mounting bracket 17 and carries an electrical contact 26 at the other end thereof adapted to be brought into contact with the fixed contact member 22 when the bimetallic arm 24 is deformed in response to a selected temperature, usually F. In this way, an electrical circuit is established from one electrode of one of the batteries 18 through the contact member 21, the conductor 23, the alarm member 15, the backing panel 14, the lower battery supporting bracket 17, and the bimetallic arm 24 to the fixed contact 22 in engagement with the opposite electrode of the other battery 18 to energize the alarm member 15. A channelshaped cover 27 extends in encasing relation to the components of the alarm unit and is open at its lower end to afiord access to the bimetallic arm 24.

The burglar alarm attachment 10 comprises an elongated rectangular base plate 30 which is oriented vertica ly and mounted on the door jamb 12 by screws 31 or the like below and in vertical alignment with the free end portion of the bimetallic arm 24. A leaf spring detent member 32 is affixed at the lower end thereof as by soldering, brazing or the like, to the base plate 30, as indicated at 33, and arches outwardly and upwardly therefrom along a generally S-shaped path. The detent member 32 terminates at its upper end in an inwardly projecting lip 34 adapted to cooperate with the outer end 35 of a leaf spring alarm actuator 36 which is likewise secured at its inner end by soldering, brazing or the like, to the base plate 30 at a point vertically aligned with and spaced above the mounted end 33 of the detent member 32. The leaf spring alarm actuator 36 is designed to be flexed outwardly of the base panel to a position wherein the outer end thereof may be caught under and retained by the lip 34 of the detent member 32 in the position illustrated in solid lines in Figure 2, in which condition the alarm actuator 36 is retained under substantial tension sufficient, upon release of the leaf spring alarm actuator 36 from such restrained condition by disengagement of the detent lip 34 therefrom, to resiliently project the end 35 into engagement with the bimetallic arm 24 and force the contact 26 thereof into engagement with the fixed contact 22.

The portions thus described are common to both the embodiments illustrated in Figures 1 and 2 and Figures 3 and 4. Figures 1 and 2 illustrate one form of the release mechanism generally indicated at 37 for the burglar alarm attachment 16 which comprises a mounting plate 33 adapted to be secured as by screws 39 or the like to the door 13 and having pivoted thereon by a stiff pivotal connection 40, a release finger 41 of sufficient length when the finger 41 is disposed horizontally as illustrated in solid lines in Figure 1 to project between the detent member 32- and base plate 30 in a position to engage and urge outwardly the detent 32 during the initial movement of the door 13 from closed to open position. When it is. desired to disable the burglar alarm system, the re ease finger 41 may be pivoted to a downward position, as illustrated in dot-dash lines in Figure 1, wherein the same will be disposed out of cooperative relation with the detent32.

in the use of the above described embodiment, the burglar alarm attachment it) is conditioned to actuate the fire alarm unit 11 by flexing the leaf spring alarm actuator 36 outwardly and downwardly relative to the base plate 39 to the position illustrated in solid lines in Figure 2, wherein the outer end 35 thereof may be caught under the projecting lip 34 of the leaf spring detent memoer 32 and retained in such flexed condition by the frictional engagement of the detent lip 34 with the actuator end 35. The release finger 41 of the release mechanism 37 will have been rotated to a horizontal position illustrated in solid lines in Figure 1 wherein the free end thereof lies between the detent member 32 and base plate 39, as shown in Figure 2. Upon surreptitious movement of the door 13 to open the same, the path of movement of the free end portion of the release finger 41 is such as to bring the release finger 41 into contact with the detent member 32 as shown in dotted lines in Figure 2 and flex the detent member 32 outwardly about its secured end 33 to release the detent lip 34 from restraining relation with the end 35 of the alarm actuator 36. The tensioned alarm actuator 36 is thereupon released to be shifted in response to its internal resilient stresses toward the free end of the bimetallic arm 24 and force the contact 26 of the bimetallic arm 24 into electrical contact with the contact member 22 on the battery supporting bracket 17 and thereby complete the electrical energizing circuit for the alarm member 15. The release finger 41 is also preferably formed of moderately resiliently deformable sheet material so as to permit slight flexing of the release finger 41 when the same engages the detent member 32 during opening movement of the door to minimize straining or permit deformation of the detent member 32. The stift pivotal mounting of the release finger 41 on its mounting plate 38 also permits pivotal movement of the finger 4i upwardly toward the lip 34 of the detent 32 during opening movement of the door 13 to further aid in minimizing permanent deformation of the detent member 32.

There is illustrated in Figures 3 and 4 a modified form of release mechanism, indicated by the reference character 42 which is integrated with a drawbolt unit. In

the embodiment illustrated in Figures 3 and 4, a drawbolt casing 43 of conventional construction having a drawbolt 44 movable rectilinearly along a horizontal axis therein and a manual control knob 45 for the drawbolt 44 is affixed to the door 13 in the conventional manner. As is more clearly shown in Figure 4-, the bevelled end portion of the bolt 44 terminates in a longitudinally projecting release finger 46 formed integral with the bolt and projecting a substantial distance beyond the end thereof. A drawbolt keeper 47 which conforms substantially to conventional drawbolt keeper construction is affixed to the door jamb 12 alongside the upper portion of the burglar alarm attachment 1% and is provided with the usual bolt-accommodating recess 48 therein to receive the bevelled end portion of the bolt 44. However, the outer side wall 49 and end Wall 50 of the keeper 47 are relieved, as indicated at 51 to provide an opening of sufiicient size to accommodate the projecting release finger 46 on the bolt 44 and permit the outer portion of the release finger 46 to extend between the detent member 32 and base plate 3%) of the burglar alarm attachment 10 when the drawbolt unit 42 is in locked condition with the bolt 44 projected into the keeper recess 48. Thus, surreptitious forcing of the door 13 with the drawbolt unit 42 in locked condition and opening movement of the door will flex the detent member 32 to release alarm actuator 36 t and energize the audible alarm member 15 of the fire alarm unit 11 in the same manner as was described in connection with the embodiment of Figures 1 and 2. The length of the release finger 46 of the embodiment of Figures 3 and 4 is such that when the bolt 44 is withdrawn to unlocked position within the drawbolt casing 43, the release finger 46 is withdrawn from underlying relation with the detent member 32, thereby disabling the burglar alarm attachment 10 when the drawbolt 42 is in unlocked condition. The relieved portion 51 of the outer side wall 49 of the drawbolt keeper 47 is of greater cross section than the horizontal projection of the release finger 46 so as to permit free movement of the release finger 46 therethrough during opening and closing movement of the door 13 when the drawbolt 42 is in unlocked condition. I

It will be apparent to those skilled in the art that the above described mechanism has broad application to a wide variety of closures and may be adapted in a manner Well known to those skilled in the art for use with windows of the easement or double hung sash types and with other varieties of window and door structure. Acordingly, While but two specific embodiments of the present invention have been particularly shown and described, it is apparent that various modifications may be made therein without departing from the spirit and scope of the invention, and it is desired, therefore, that only such limitations be placed upon my invention as are imposed by the prior art and set forth in the appended claims.

I claim:

1. In burglar alarm apparatus adapted for use with an electrically operable alarm unit of the type including an electrically energizable alarm and electrical supply circuitry therefor including a normally open-circuited contact arm controlling the electrical supply to said alarm and accessible for manipulation from externally of the alarm unit, the combination comprising movable actuator means adapted to be positioned adjacent the contact arm and adjacent a relatively movable closure, resilient means for continuously urging said actuator means into contact-closing engagement with said contact arm, detent means for releasably holding said actuator means in a restrained condition out of engagement with said contact arm, and release means adapted to be fixed to the movable closure and selectively extendable therefrom into juxtaposed relation with said detent means to be intercepted by said detent means during relative movement of said closure and disengage said detent means from restraining relation with said actuator means to release the latter to engage and force said contact arm to alarm-energizing condition.

2'. In burglar alarm apparatus adapted for use with an electrically operable alarm :unit of the type including an electrically energizable alarm and electrical supply circuitry therefor including a normally open-circuited contact arm controlling the electrical supply to said alarm and accessible for manipulation from externallyof the. alarm unit, the combination comprising a resilient elongated actuator member fixedly supported at one end thereof and adapted to be positioned adjacent said contact arm and adjacent a relatively movable closure, said actuator member having a sufficient range of flexing movement to bring a terminal portion thereof into contact-closing engagement with said contact arm adjacent one limit of'its range of movement, resilient elongated detent means supported at one end thereof in fixed spaced relation to said supported end of said actuator member and having a projecting terminal portion including a catch lip to engage the terminal portion of said actuator member and restrain the same in resiliently stressed condition flexed away fromengagement with said contact arm, and release means therefor adapted to be affixed to the movable closure and having a projection movable with said closure selectively extendable between said detent member and said actuator member when said closure is in closed position to be transferred by movement of said closure into contact with said: detent member for camming the same out-of restraining engagement with said actuator member and releasing said actuator member to engage and force said contact arm to circuit-closing condition energizing said alarm.

3 In burglar alarm apparatus adapted for use with an electrically operable alarm unit of the type including an electrically energizable alarm signal generator and supply circuitry therefor including a flexible contact arm forming one contact of a normally open switch controlling the electrical supply to said alarm generator and accessible for manipulation from externally of the alarm unit, the combination comprising an elongated rigid mounting plate adapted to be positioned adjacent a relatively movable closure with its longitudinal axis intercepting a portion of said contact arm, an elongated leaf spring actuator member fixed at one end thereof to said mounting plate and projecting therefrom along an axis lying in the longitudinal medial plane of said mounting plate, said actuator member having a suflicient range of flexing movement to bring a terminal portion thereof into engagement with said contact arm when said mounting plate is mounted adjacent said arm to force said contact arm into switch-closing position, resilient elongated detent member comprising a leaf spring fixed at one end thereof on said mounting plate and projecting therefrom along an axis lying in said medial longitudinal plane, said detent member terminating in a catch lip at the free end thereof to engage the terminal portion of said leaf spring actuator member and restrain the same in resiliently stressed condition flexed away from engagement with said contact arm, said detent member being disposed in partially overlying spaced relation to said actuator member to define an intervening space therebetween, and release means adapted to be afiixed to the movable closure and having a projection movable with said closure selectively extendable into said intervening space between said detent member and said actuator member when said closure is in closed position to be shifted by opening movement of said closure into contact with said detent member for camming the same out of restraining engagement with said actuator member and releasing said actuator member to be flexed in response to its resilient internal stresses into engagement with said contact arm and force said contact arm into switch-closing condition.

4. In burglar alarm apparatus adapted for use with an electrically operable alarm unit of the type including an electrically energizable alarm signal generator and supply circuitry therefore including a flexible contact arm forming one contact of a normally open switch controlling the electrical supply to said alarm generator andaccessible for manipulation from externally of the alarm unit, the combination comprising an elongated rigid mounting plate adapted to be positioned adjacent a relatively movable closure with its longitudinal axis intercepting a portion of said contact arm, an elongated leaf spring actuator member fixed at one end thereof to said mounting plate and projecting therefrom along an axis lying in the longitudinal medial plane of said mounting plate, said actuator member having a sufficient range of flexing movement to bring a terminal portion thereof into engagement with said contact arm when said mounting plate is mounted adjacent said arm to force said contact arm into switch-closing position, resilient elongated detent member comprising a leaf spring fixed at one end thereof on said mounting plate and projecting therefrom along an axis lying'in said medial longitudinal plane, said detent member terminating in a catch lip at the free end thereof to engage the terminal portion of said leaf spring actuator member and restrain the same in resiliently stressed condition flexed away from engagement with said contact arm, said detent member being disposed in partially overlying spaced relation to said actuator member to define an intervening space therebetween, and release means adapted to be atfixed to the movable closure including a mounting plate and an elongated release finger pivotally supported on said plate for movement to selected positions of adjustment, said release finger being of sufficient length when located in one selected position of adjustment to project into said intervening space between said detent member and said actuator member when said closure is in closed position to be shifted by opening movement of said closure into engagement with said detent member adjacent said catch lip and cam the same out of restraining engagement with said actuator member to release said actuating member to force said control arm into switch-closing condition, and said release finger having another position of adjustment wherein the path of movement of the same upon opening movement of said closure is spaced from said detent member.

5. A burglar alarm accessory for fire alarm apparatus of the type having an electrically energizable alarm signal generator and normally open thermally responsive switch means controlling the energization of said generator including a bimetallic contact strip fixed at one end thereof and deformable about said fixed end into switch-closing position, said accessory comprising movable actuator means adapted to be positioned adjacent the bimetallic strip and adjacent a relatively movable closure, resilient means for continuously urging said actuator means into contact-closing engagement with said bimetallic strip, dctent means for releasably holding said actuator means in a restrained condition out of engagement with said himetallic strip, and release means adapted to be fixed to the movable closure and selectively extendable therefrom into juxtaposed relation with said detent means to be intercepted by said detent means during relative movement of said closure and disengage said detent means from restraining relation with said actuator means to release the latter to engage and force said bimetallic strip to alarm-energizing condition.

6. A burglar alarm accessory for fire alarm apparatus of the type having an electrically energizable alarm signal generator, and normally open thermally responsive switch means controlling the energization of said generator including a bimetallic contact strip fixed at one end thereof and deformable about said fixed end into switch-closing position, said accessory comprising an elongated rigid mounting plate adapted to be positioned adjacent a relatively movable closure with its longitudinal axis intercepting a portion of said bimetallic strip, an elongated leaf spring actuator member fixed at one end thereof to said mounting plate and projecting therefrom along an axis lying in the longitudinal medial plane of said mountasaasoo ing plate, said actuator member having a suflicient range of flexing movement to bring a terminal portion thereof into engagement with said bimetallic strip when said mounting plate is mounted adjacent said arm to force said bimetallic strip into switch-closing position, resilient elongated detent member comprising a leaf spring fixed at one end thereof on said mounting plate and projecting therefrom along an axis lying in said medial longitudinal plane, said detent member terminating in a catch lip at the free end thereof to engage the terminal portion of said leaf spring actuator member and restrain the same in resiliently stressed condition flexed away from engagement with said bimetallic strip, said detent member being disposed in partially overlying spaced relation to said actuator member to define an intervening space therebetween, and release means adapted to be amxed to the movable closure and having a projection movable with said closure selectively extendable into said intervening space between said detent member and said actuator member when said closure is in closed position to be shifted by opening movement of said closure into contact with said detent member for camming the same out of restraining engagement with said actuator member and releasing said actuator member to be flexed in response to its resilient internal stresses into engagement with said bimetallic strip and force said bimetallic strip into switchclosing condition.

7. A burglar alarm accessory for fire alarm apparatus of the type having an electrically energizable alarm signal generator, and normally open thermally responsive switch means controlling the energization of said generator including a bimetallic contact strip fixed at one end thereof and deformable about said fixed end into switch closing position, said accessory comprising an elongated rigid mounting plate adapted to be positioned adjacent a relatively movable closure with its longitudinal axis intercepting a portion of said bimetallic strip, an elongated leaf spring actuator member fixed at one end thereof to said mounting plate and projecting therefrom along an axis lying in the longitudinal medial plane of said mounting plate, said actuator member having a sufiicient range of flexing movement to bring a terminal portion thereof into engagement with said bimetallic strip when said mounting plate is mounted adjacent said arm to force said bimetalic strip into switch-closing position, resilient elongated detent member comprising a leaf spring fixed at one end thereof on said mounting plate and projecting therefrom along an axis lying in said medial longitudinal plane, said detent member terminating in a catch lip at the free end thereof to engage the terminal portion of said leaf spring actuator member and restrain the same in resiliently stressed condition flexed away from engagement with said bimetallic strip, said detent member being disposed in partially overlying spaced relation to said actuator member to define an intervening space therebetween, and release means adapted to be affixed to the movable closure including a mounting plate and an elongated release finger pivotally supported on said plate for movement to selected positions of adjustment, said release finger being of sufiicient length when located in one selected position of adjustment to project into said intervening space between said detent member and said actuator member when said closure is in closed position to be shifted by opening movement of said closure into engagement with said detent member adjacent said catch lip and cam the same out of restraining engagement with said actuator member to release said actuating member to force said bimetallic strip into switch-closing condition, and said release finger having another position of adjustment wherein the path of movement of the same upon opening movement of said closure is spaced from said detent member.

No references cited.

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