US1499951A - Burglar alarm - Google Patents

Description

Jul 1. 1924.

J. SOSOKA BURGLAR ALARM Filed Oct.

Fla. 1. Fig. 2.

FIG. 8.

Patented July 1, 1924,

UNHTED mm SQSOKA, or CLEVELAND, onion nunenan ALARM.

Application filed October 15, 1823. Serial an. 668,702.

T (3 all whom it may concern:

Be it known that I, J OHN SosoKA, a citizen of Hungary, residing at Cleveland, in thecounty of Guyahoga and State of Ohio, have invented certain new and useful Improvements in Burglar Alarms, of which the following a specification.

This invention relates to certain new and useful improvements in burglar alarms and has particular reference to an audible signal adapted to be sounded upon unauthor i z ed opening of a door or the turning of the knob spindle thereof.

The primary object of the invention is to provide a burglar alarm wherein a bell device embodying a hammer arm operated by the usual escapement mechanism of clock apparatus has a pair of spring devices associated therewith for normally holding the hammer arm against movement and adapt ed to be shifted with respect to the hammer arm by devices connecting the spring members withthe spindle of a door knob to permit the hammer arm to strike the bell.

With the above and other objects in view as the nature of the invention is better understood, the same consists of the novel form, combination and arrangement of parts hereinafter more fully described, shown in the accompanying drawing and claimed.

In the drawing, wherein like reference characters designate corresponding parts throughout the several views,

Figure 1 is aiiragmentary front elevational view of a door and easing with the alarm mechanism supported on the door and operatively connected to the knob spindle,

Figure 2 is a top plan View of the alarm bell with the cover plate of the clock mechanism removed,

Figure 3 is a vertical cross sectional view taken on line IIIIII of Fig. 2 showing the bell hammer retained in an inoperative position with the control devices for the bell hammer illustrated in dotted line position permitting the latter to function,

Figure 4 is an end elevational view of the panying drawing, Figure 1 illustrates a door 1 associated with a casing or frame 2 with an alarm device generally designated by the numeral 3 carried by the door 1 and in the form of a bell mechanism having a hammer arm that is controlled in its oper ation by the wire 4 connected to the knob spindle 5, turning of the knob spindle in either direction releasing the bell hammer and causing the same to strike the bell of the alarm device to indicate unauthorized tampering with the door knob spindle;

The alarm mechanism embodies a base plate 6 provided with openings 7 adjacent the edges thereof to facilitate mounting of the base plate upon the door 1, the lower end of the base plate 6 carrying a cover plate'8 through the medium of connecting pins 9 and 10 that is spaced therefrom as shown in Figs. 3 and 1. A bell 11 is carried by the upper end of the base plate 6 and is disposed upwardly of the cover plate 8 as shown in Fig. 1.

Clock nechanism including a spindle 12 is journaled in the plates 6 and 8 and carries a winding handle 13 outwardly of the cover plate 8, the shaft 12 having a ratchet wheel 14 fixed thereto with which a pawl 15 carried by a gear wheel 16 is engaged, an arcuate spring 17 carried by the gear 16 engaging the pawl 15 to retain the same in engagement with the ratchet wheel 14. A band spring 18 is anchored at one end to the post 19 extending between the plates 6 and 8 and has the inner end thereof secured to the shaft 12. The shaft 20 jour-' naled at its ends in the plates 6 and 8 carries a lantern gear 21 that is engaged by the gear 16, the lantern gear having an escapement wheel 22 rigid therewith that cooperates with the escapement lever 23 of the bell hammer 24. It will therefore be seen that upon rotation of the shaft 12 to place the spring 18 under tension, reverse rotation of the shaft being locked to the gear 16 through the medium of the ratchet wheel 14 and pawl 15 will cause rotation of the gear 16 and the escapement mechanism for the bell hammer 24.

To retain the bell hammer 2 1 against movement when the spring 18 is under tension, there is provided a spring arm 25 secured at one end as at 26 to the base plate 6, the arm 25 carrying a pin 27 depending from the lower side thereof as shown in Figs. 2 and 3 to extend across the path of movement of the bell hammer 2e to prevent the same from striking the bell 11. The normal position of the spring arm 24 is such as to dispose the pin 27 outwardly of the path of movement of the bell hammer and to shift the arm 25 to prevent action of the bell hammer, there is provided a second spring member in the form of an arm 28 secured at its upper end as at 29 to the cover plate 8, the arm 28 be ing bent intermediate its ends to provide a trigger 30 and an outwardly directed rod 31 slidably extending through openings 32 in the connecting posts 10 with the trigger end 30 normally overlying the spring arm 25 to retain the same depressed with the pin 27 carried thereby in the path of movement of the bell hammer 24. The wire 4 connected as at 33 to the outer end of the rod 31 has the other end thereof secured as at 34: to the curved plate 35 that engages the spindle 5 of the door knob mechanism and is retained in position thereon by the spindle 10 passing through the opening 36 in the plate 35. t

With the spring 18 under tension, ant the arm 25 maintained in a depressed con dition by the trigger end 30 of the spring arm 28, the pin 27 is disposed in the path of movement of the bell hammer and the same is prevented from striking the bell 11. hen the knob spindle 5 is rotated in either direction, the wire connection 4t between the knob spindle and the rod 31 of the arm 28, lowers the rod 31 and displaces the trigger 30 from overlying engagement with the spring arm 25, the resiliency of the arm 25 causing the same to move outwardly to the dotted line position shown in Fig. 3 and permitting the bell hammer 24 to function in striking the l bell 11 indicating unauthorized tampering with the door lock mechanism.

lVhile there is herein shown and described the preferred embodiment of the present invention, it is nevertheless to be understood that minor changes may be made therein without departing from the spirit and scope of the invention as claimed.

What is claimed as new is In an alarm device including a frame supporting a bell, a hammer arm pivoted on the frame adjacent the bell, and means to oscillate the hammer arm; a latch mechanism to hold the hammer arm against oscillation and comprising a horizontally disposed spring arm having one end secured to the frame remote from said hammer arm and its other end provided with a laterally extending pin movable into and out of the path of the hammer arm, the resiliency of the spring arm tending to move the pin out of said path, a second spring arm at right angles to the first having one end fixed to the frame in front of the free end of the first spring arm and being provided with an angularly bent portion constituting a latch for the first mentioned arm to hold it releasably flexed and the pin in the path of the hammerarm, and pull means attached to the free end of the second spring arm. 7

In testimony whereof I afliX my signature.

JOHN SOSOKA.

Images