US3537093A - Alarm system - Google Patents

Description

Oct. 27, 1970 L. D.'PERRET Ill I 3,

' ALARM SYSTEM Filed June 23, 196? '2 Sfieet s-Sheet 1 4 INVENTOR LOUIS D. PERRET 111 ATTORNEYS Oct. 27, 1970 L. D. FERRET m 3,537,093

I ALARM SYSTEM Filed June 23, 1967 2 Sheets-Sheet 2 INVENTOR LOUIS D. PERRET III ATTORNEYS United States Patent 3,537,093 ALARM SYSTEM Louis D. Perret III, 282 Citrus Road, Haralran, La. 70123 Filed June 23, 1967, Ser. No. 649,428 Int. Cl. G08b 19/00, 13/08 US. Cl. 340-274 Claims ABSTRACT OF THE DISCLOSURE A trip wire-actuated portable alarm system of the type embodying a thermoplastic line extensible from a rotatable reel within the alarm box to the perimeter of the area being surveilled, an alarm bell being actuated electrically as the line is tripped by an intruder or consumed by fire.

BACKGROUND OF THE INVENTION Field of the invention Alarm systems particularly a signal box type alarm having a thermoplastic trip wire extensible throughout an area being surveilled and being automatically responsive to a condition for actuation, for example, loss of tension on the line due to tripping or due to fire.

Description of prior art Related techniques are treated in the following prior art references: Staub, 856,924; Castronovo, 1,802,805; Rushing, 2,398,966; Christie, 2,643,313; Hollingsworth, 2,907,014; Hewitt, 3,175,207.

Earlier inventors have contemplated the fusible or nylon trip wire alarm system. Staub and Castronovo are early examples of this type of alarm, albeit employing complicated alarm devices. Rushing, Hollingsworth and Hewitt are representative of the more recent art employing a fusible line and a motor-operated alarm clapper. Hollingsworth employs a tension spring to close his contact upon burning of the string and Hewitt door-mounts his device by means of suction cups. Christie contemplates use of his device as a fire alarm when in the first position on the ceiling, and, secondly, as a burglar alarm when in the second position on the floor of a room.

None of these devices have a tripping sensitivity comparable to applicants device and none have the positive setting and locking feature disclosed by applicant. As a result, none of the earlier alarms are as sensitive to fire or movement for tripping and none can be positively locked in either the off position or the on position. The effective result of locking in the on position is that the alarm, once tripped, cannot be turned off except by using the key which originally set the alarm.

SUMMARY OF THE INVENTION According to applicants invention, a portable housing embodies a pair of alarm bells, a rotatable reel or spool with nylon line extensible through the housing and a bell actuating mechanism, including a spring tensioned spindle contacting the surface of the spool and actua-ble to close an electrical contact operating the clapper, as the spool is moved in either direction by tripping of the nylon line or by fusing thereof. The spindle is set in alarm on position by means of a lock tumbler and cam, the key being removed from the lock tumbler upon setting the alarm in on position.

Inasmuch as the housing is small and the reel embodies a virtually invisible extensible nylon line, the device may be used as a burglar alarm or fire alarm and, it is contemplated, enemy troop movement alarm. The limits of the area being surveilled and determined, of course, by extending the nylon line as a trip wire, for example, as

3,537,093 Patented Oct. 27, 1970 illustrated in FIG. 1, around the door knob, and around a window locking bracket or a door opening panel. A soldier, for example, could define his surveillance periphery by extending the nylon line with stakes or the like around a foxhole and locking the device in alarm on position so as to be notified by a ringing bell as enemy troops trip the virtually invisible nylon line during night or daytime operations. Since the device weighs only a pound or two it can be easily carried in the soldiers pack.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmementary perspective of the alarm system set in a conventional room with the extensible nylon trip wire 26 extending around a door knob, a window opening bracket and being hooked at its free end to a door opening panel;

FIG. 2 is a top plan of the alarm housing with the cover removed showing lock tumbler, battery energizer, clapper, reel and bell elements;

FIG. 3 is a side elevation, partially in section showing the bell, clapper, reel, lock tumbler and spindle-actuating elements set in alarm on position, so that the alarm bells will ring, upon tripping or fusing of line 26;

FIG. 4 is a fragmentary elevation showing the spindle in locked alarm off position with cam 46 and pawl 44, forcing spindle 66 ends free of contact with the reel and contact plate elements; and

FIG. 5 is an enlarged perspective showing the eccentrically mounted bell ringing clapper positioned between the two alarm bells.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 alarm device 10 is illustrated as positioned upon a room floor and comprising housing 12 into which on-off key 14 has been inserted. A resilient, fiamable trip wire 26 is illustrated as extending from housing 12 thence to door 18 knob 20 around which it may be wound, thence to window 22 locking bracket 24 and thence to swinging door 28 panel 30 to which it is secured by means of open end hook 32.

As door 18, window 22 or swinging door 28 are moved or opened the bell alarm within housing 12 is actuated. Alternatively, tripping of wire 26 or fusing thereof as a result of fire will result in actuation of the alarm, provided that on-off key 14 has set the alarm in on position. The alarm will continue to be actuated until the key is reinserted, turning the lock tumbler to alarm off position. The alarm components are further illustrated in FIG. 2 wherein housing 12 is shown as enclosing a bell mounting section 34 having end panel 64, battery section 36 and locking section or quadrant 38 through which extends lock tumbler 40, having axial shaft 42. Eccentric 46 is secured at the inner end of shaft 42 for contacting of alarm setting pawl 44 set in support bracket 76. Alarm setting pawl 44 is urged downwardly to alarm actuating position by means of compression spring 80. Pawl 44 at its top has eyelet 78 encompassing spindle arm 58 in its midportion.

As illustrated in FIG. 3 alarm bells 52 and 54 are mounted, respectively, upon Shaft 50 and 48, the latter shaft supporting also trip line reel 56. Reel 56 is rigidized by means of bracket 58 secured to housing wall 12 by means of bolt 60, welding or the like.

The resilient line 26 which may be manufactured from nylon or thermoplastic extends through hole 62 in panel 64, then through a similar hole (not illustrated) in housing 12 for attachment by means of hook 32 to exterior elements defining the surveillance periphery. Spindle 66 is supported in shaft eyelet 78 and has at its reel contacting end rubber tip 68 contacting the surface of reel 56 when in alarm on position as in FIG. 3. When the lock tumbler 40 and cam 46 are turned by key 14 to alarm off position, eccentric 46 forces pawl 44 upwardly, thus moving rubber tip 68 from contacting the reel surface. In this position the alarm is incapable of being actuated. Spindle 66 is urged into contact with reel 56 by means of tension spring 72 secured to the locking section wall by means of set screw 70 or the like at one end and being secured to arm 74 pivoted to pawl 44. Spring 72 thus urges the spindle vertically downward both against reel 56 and into contact plate 90 at its other end. At the plate contact end of spindle 66 bracket 84 secured to wall 38 supports tent cover 86 loosely enclosing the spindle free end and vertical trip plate support 88 upon which the free spindle end rests. As trip wire 26 is actuated in either direction either by contact of the wire or fusing thereof, reel 56 moves, and in turn, rubber tip 68 is caused to move, moving spindle 66 to either side of vertical trip plate 88 from which it is jerked emphatically by means of overriding springs 72 and 80 to contact plate 90. The battery circuit is thus closed by means of wire 98 connected to contact plate 90 at point 92, wire 100 interconnecting battery elements 94 and 96 at opposite poles and wire 102 interconnecting battery 96 with the armature proper 104, which is secured to wall 34 by means of bracket 112 and stove bolt 108 and nut 100.

Conventional armature 104 has shaft 114 extending inwardly of the housing with an eccentric 116 mounted therein, as illustrated in FIGS. 2 and 5. Clapper arm 118 is secured to eccentric 116 by means of collar 122 and has at its free end bell contacting head 120. As armature 104 is caused to rotate upon tripping of line 26 and contact of the free spindle end with contact plate 90, eecentric 116 causes the clapper head 120 to strike alternately the peripheral surfaces of bells 52 and 54.

This tripping of the alarm is possible in the position illustrated in FIG. 3, but prevented in the alarm off position, illustrated in FIG. 4. So long as the cam 46 is in the alarm on position illustrated in FIG. 3, the spindle 66 free end contact with plate 90 will remain and the alarm will continue ringing until the key 14 is reinserted so as to turn the lock tumbler and cam 46 to push spindle 66 into alarm off position and out of contact with reel 56 and contact plate 90, as illustrated in FIG. 4.

What is claimed is:

1. An alarm system comprising:

(A) a housing;

(B) rotatable reel means supported in said housing;

(C) a resilient line extensible from said reel through said housing for securement to an exterior base; and

(D) an alarm component, including:

(i) bell means supported within said housing;

(ii) a clapper having a bell ringing head and extending from said housing to a position of proximity with respect to said bell; (iii) a bell actuating contact plate and electrical energy source positioned adjacent said reel; (iv) clapper actuating means interconnecting said contact plate and said clapper so as to actuate said clapper upon closing of said contact plate with said electrical energy source; and

(v) a spindle supported intermediate said reel and said contact plate, one end of said spindle contacting said reel and being rotatable upon r0- tation of said reel and the other end of said spindle being positioned to close said contact plate with said electrical energy source upon movement of said reel.

2. An alarm system as in claim 1 wherein said rotatable reel is spring-urged so as to Wind said resilient line.

3. An alarm system as in claim 2, said clapper actuating means including:

(A) an electrically energizable armature having a rotatable shaft; and

(B) an eccentric attached to said shaft and said clapper being connected at one end to said eccentric so as to contact said hell with its head upon rotation of said armature.

4. An alarm system as in claim 3, said bell means including two bells supported in said housing opposite the head of said clapper.

5. An alarm system as in claim 4, said reel and one of said bells being coaxially mounted within said housing.

6. An alarm system as in claim 5, including an alarm setting mechanism, further comprising:

(i) a lock tumbler extending through said housing and adapted for rotation by means of an externally insertable key;

(ii) a shaft extending inwardly of said housing from said tumbler;

(iii) an eccentric mounted upon said shaft; and

(iv) a spring compressed setting pawl interconnecting said eccentric and midportion of said spindle in a position of readiness so as to urge said spindle to contact said reel at one end and to support the spindle free end above said contact plate upon turning of said key.

7. An alarm system as in claim 6, said electrical energy means including a contact plate wired to said batteries and thence to said armature and having a vertically extending trip plate adapted for supporting the free end of said spindle upon turning of said key and eccentric so as to set said alarm.

8. An alarm system as in claim 7, including spring means interconnecting said housing and said spindle so as to override said setting pawl and urge said spindle to contact said contact plate.

9. An alarm system as in claim 1, said resilient line being of the thermoplastic type.

10. An alarm system as in claim 6, wherein said lock tumbler and said shaft constitute the only means for lifting said spindle so as to open said alarm contact upon turning of said key.

References Cited UNITED STATES PATENTS 1,238,532 8/1917 Lemberg 345-274 JOHN W. CALDWELL, Primary Examiner J. M. BOBBITT, Assistant Examiner US. Cl. X.'R. 340232, 420

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