US1424891A - Burglar alarm - Google Patents

Description

I. A. FOLEY BURGLAR ALARM,

-APPLICATION'FILED SEPT-1, 1921.

1 ,42%,89 1 Patented Aug. 8, 1922.

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JAMES A. FQLEY, OF OMAHA, NEBRASKA.

BURGLAB, ALARM.

Application filed September 1, 1921. Serial No. 497,530.

T 0 all whom it may concern:

Be it known that JAMns A. FOLEY, a citizen of the United States, residing at Omaha, in the county of Douglas and State of Nebraska, has invented certain new and useful Improvements in Burglar Alarms, of which the following is a specification, reference being had therein to the accompanying drawing. 7 p

The invention relates to burglar alarms and has for its object to provide a device of this character particularly adapted for use adjacent doors and so constructed that when the door is opened a wedge shaped member will be engaged by said door, moved longitudinally against the action of a spring and release bell ringing spring actuated mechanism and beheld in said operative po sition by means of a gravity actuated pawl carried by the wedge shaped member, which pawl cooperates with a base notch. Also to provide the base of the device with means or preventing slipping of the same when actuated by the door, said means coinprising a substantially flat member formed from soft rubber which hugs the floor and closely engages the same, thereby obviating the use of prongs which damage the floor.

A further object is to so mount the pawl and the wedge shaped member, that when said wedge shaped member is forced downwardly at its rear end the pawl will'be raised out of engagement with the notch thereby allowing the resetting of the wedge shaped member under the influence of its actuating spring. 2

With the above and other objects in view the invention resides in the combination and arrangement of parts as hereinafter set forth, shown in the drawings, described and claimed, it being understood that change in the precise embodiment of the invention may be made within the scope of what is claimed without departing from the spirit of the invention.

In the drawings Figure 1 is a perspective View of the burglar alarm, showing the same disposed ad-' jacent the lower edge of a door.

Figure 2 is a longitudinal sectional view vertically through the alarm taken on line of Figure 1.

Figure 3 is a top plan view of the alarm showing the same with the bell removed to better illustrate the structure.

Figure 1 is a vertical sectionalview transversely through the wedge shaped member and its guide base, said view. being taken on line 4-4 of Figure 1.

Figure 5 is a horizontal detail sectional view taken on line 55'of Figure 2.

Referring to the drawings, the numeral 1 designates a base, which 'baseis preferably formed from sheet metal and is provided with an upwardly extending annular flange 2 and with an outwardly extending integral projection 3,.between the flanges (l of which a longitudinally slid-able wedge shaped door engaging member 5 is slidably mounted. The wedge shaped member 5 ad.- jacent its rear end is pivotally mounted on pins 6, which pins extend through the flanges 41; and throughelongated slots 7 in the side walls 8 of the wedge shaped memher 5. It will be noted that the wedge shaped member 5 is at points beyond its forward end spaced from the bottom of its extension 3 and therefore that when pressure is applied at 9 to the rear end of the block 5, the gravity actuated pawl 10, which is pivoted at 11 to the side 8 of the wedge shaped member 5 will be rocked upwardly at its nose end 12, thereby through the medium of the pin 13, which is carried by said pawl and which when the nose 12 is in engagement with the notch let of one of the flanges 4 will engage the bottom 15 of a slot 16 in one of the, walls 8, and thereforewill cause the nose end of the pawl to be raised clear of the notch 14 and the block 5 and its pawl to be forced forwardly through the medium of a leaf spring 17, which leaf spring forces the shaft 18 forwardly, which shaft is loosely connected at 19 to the rear end of the wedge shaped block 5. It will be seen that when the free end 20 of the door is swung open that it will engage a wedge shaped member 5, force said member rearwardly against the action of the leaf spring 17, which is secured at 21 to a mechanism supporting plate 22 having lug and slot connections 23 with the upper marginal edge of the flange 2 of the base, and on which plate 22 a conventional form of bell 20 i arm allowed to oscillate with the escape ringing mechanism 24 is disposed, which mechanism is actuated by a spring 25, housed within the base 1. and controlled by an escapement pawl 26, which escapement pawl oscillates on its pivotal point 27 and has connected thereto a striker 28, the

striker 29 of which cooperates with the bell 30 for ringing a continuous alarm until the pawl 10 is released and the wedge shaped member 5 again reset. Extending upwardly ment pawl 26, which cooperates with the teeth of anescapement wheel 33.

It has been'found that means must be provided for preventing sliding of the device on the floor and that the action must be sufliciently retarded to allow the rearward movement of the wedge shaped member 5. Heretofore prongs have been provided on the base, which prongs are adapted to be forced into the floor and where used they damage the floor to such an extent the devices cannot be used. To overcome this difficulty and to provide means for retarding the movement sufficiently for tripping the actuating operations, the base 1 is provided with a flat sheet of soft rubber 34, which rubber is adhesively joined at 35 to the under side of the base 1, and by being formed from soft rubber, it closely hugs the surface in such a manner that when thewedging action starts the device'will be prevented from slipping and this prevention of slipping increasing in ratio as the downwardpressure on the: de-

vice as a whole increases incident to the wedging action.

From the above it will be seen that a burglar alarm is provided for doors, which preventing horizontal slipping of the same,

burglar alarm comprisinga base having a said means being so constructed that marring of the flooring will be prevented.

The invention having been set forth what is claimed as new and useful is l. A door operated burglar alarm comprising a base, an extension carried by said base, guide flanges carried by said extension, a wedge shaped block slidably and pivotally mounted between said flanges, a dog carried by said wedge shaped member and cooperating with a notch in one of said flanges for holding the block in rearward position, a bell ringing mechanism disposed on the rear end of the base, a connectingrod carried by the wedge shaped member, a leaf-spring connected to said connecting rod and forming means for forcing the wedge shaped member forwardly and holding the bell ringing mechanism against operation.

2. The combination with a door actuated burglar alarm comprising a base having a spring actuated bell ringing mechanism at one end thereof and controlled through the medium of a longitudinally disposed and movable shaft, of a door engaging wedge carried by said base, said door engaging wedge being loosely connected 'to the outer end of the shaft, said wedge shaped member being pivoted vertically and longitudinally movable in the base, a gravity actuated pawl carried by said door engaging wedge and c0- operating with a notch in the base, and a stop carried by the wedge for limiting the downward movement of the pawl and so positioned that when the wedge is rocked on its pivotal point thepawl will be moved'out of engagement with the notch.

3. The combination with a door actuated spring actuated bell ringing mechanism at one end thereof and controlled through the movement of a wedge shaped door engaging member, said door engaging member being longitudinally movable on the base, ofmeans for holding said door engaging member, in

' operative position, said means comprising a dog pivoted to the wedge shaped member and cooperating with a notch in the base.

In testimony whereof I hereunto afiix my,

signature. JAMES A. FOLEY,

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