US1464050A - Burglar alarm - Google Patents

Description

Aug. 7, 1923. 1,414,650

A. man-MP BURGLAR ALARM Filed May 25 1922 Patented Aug. 7, 1923.

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ARCHIE J. SHIMP, O33 ROCKFORD, ILLINOIS.

BURGLAB ALARIVL Application filed May 25,

To all whom it may concern:

Be it known that I, AnoHIn J. SHIMP, a citizen of the United States, residing at Rockford, in the county of lVinnebago and State of Illinois, have invented certain new and useful Improvements in Burglar Alarms, of which the following is a specification.

This invention pertains in general to burglar alarms, and has more particular reference to those of the portable type adapted to be attached to and actuated by a door knob, or to be actuated by a key or a window cord for setting off the alarm.

The primary object of this invention is to provide a new and improved burglar alarm of the character described. which comprises but few parts so compactly arranged as to make a small portable device which may be conveniently carried about, and which will serve in a practical and efficient manner the purposes intended.

I have also aimed to provide a burglar alarm which may be easily set and attached either to a door knob, a key, or in connection with a window cord, and which will instantly sound an alarm upon actuation of any of said parts.

Other objects and attendant advantages will be appreciated by those familiar with this art as the invention becomes better understood by reference to the following description when considered in connection with the accompanying drawing, in which Figure 1 is a view of a portable burglar alarm embodying my invention attached to the shank of a door knob in set position, with the bell removed;

Fig. 2 is a similar view showing the alarm set off;

Figs. 3 and 1 are sectional views taken on the lines 3-3 and 4-4, respectively, of Figs. 1 and 2;

Fig. 5 is a sectional view taken on the line,55 of Fig. 1;

Fig. 6 is a side view of the burglar alarm; and

Figs. 7 and 8 are face views of modified forms of the burglar alarm.

Referring more particularly to the drawings, Figs. 1 to 6 inclusive, show the preferred embodiment which is adapted for attachment to and actuation by a door knob. This comprises, generally stated, an alarmsounding device, a setting device, and a trip plemental frame member 16.

1922. Serial No. 583,517.

device for setting 01f the alarm, which will be described in order.v

The alarm sounding device comprises a suitable hell 9 attached to a central post 11, in turn fixed to a base of the frame member 12. A striker, designated generally by 13, is adapted to be operated by a suitable spring motor for striking the inside of the bell for sounding the alarm. In the present instance, this spring motor consists of a spiral spring 14 attached at its inner end to the post 11 and at its outer end to one of the posts 15, which support a sup- This spring will be wound by turning the bell 9, and the spring pressure will be transmitted through gearslr' to an escapement wheel 18. The escapement member 19 co-operating with the wheel 18 is pivoted at 21 and fixed to the striker 13. The striker has an arm 22 extending to the opposite side of its pivot 21, which arm. is adapted to be nor mally held by the setting device and to be released thereby for putting the striker into operation.

The setting device comprises a spring member designated generally by 23, fixedly attached at its end 24 to the frame member 12 and having a vertically disposed portion 25 the upper end 26 of which is adapted in the set position of the member 28, to be disposed in the path of the striker arm 22 as shown in Fig. 3, for preventing operation of the striker. The spring member 23 is shown held in said set position by the upstanding part 26 of a setting member 27. This member 27 slidably mounted on the frame member 12 is adapted to be manually moved to the left to the set position shown in Figs. 1 and 3 by pushing inwardly on the projecting end 28. A contractile spring 29 connected at one end with the frame 'member 12 and at its opposite end with ,shown in Fig. 1.

and upon movement of said member 27 to the dotted line position, the soring member 23 will be slightly lowered until its depending finger 38 rests on a trip member described later. This is the operative set position in which the upper end 28 of the spring member still holds the striker arm 22 against operation. The trip device comprises a trip member 32 pivotally mounted at 33 on the frame member 12 and a trip-actuating member 3A pivotally mounted at 35 on a part 36 hinged at 37 to the frame member. The inner end of the trip member- 32, disposed beneath said depending finger 38, is notched at 39 and 4L1 for the reception of said finger 38, as will be presently described. Any suitable connection may be provided between the mem: bers 32 and 3A for oscillating the former by the latter. The trip-actuating member 34 has in the present instance a pair of spring. arms 42 adapted to be detachably clamped to the shank of a door knob, as is plainly The outer end of the member 3e may, however, be suitably shaped for attachment to or connection with any part, movement of which is intended to set off the alarm.

The operation of this form of my invention is as follows: The parts as shown in full lines in Figs. 1 and 3, are in the locked set position, that is, the setting member 27 has been pushed inwardly, thereby raising the spring member 23 to the settingposition and bearing against the adjacent edge of the trip member 32 so as to lock the same against tripping movement. In this locked set position, the alarm device may be at-' tached to the door knob with little danger of accidentally setting off the alarm. After the device has been properly attached, the attendant will pull the setting member 27 outwardly to the dotted line position shown in Fig. 3, thereby allowing the depending finger 38 to rest on the inner end of thetrip member 32 in the operative set position. When now the door knob is turned in either direction, the trip-actuating member 34 will be oscillated, as for example in a clockwise direction, as shown in F 2, and will oscillate the trip member 32 in the opposite 'di rection, thereby movin said trip member from under the finger 3S and allowing the latter to enter the notch 39 under the. influence of the potential spring pressure of the member 23. By this movement of the spring member 23, its end will be withdrawn from the striker arm 22, thereby setting off the alarm. When it is desired to reset the device, it is only necessary to push in the setting member 27 to the locked set position and pull said member out for the final settin position. As shown in Fig. 6, the radially projecting trip-actuating member may be swung back on its hinged support against the back of the frame member 12, so that the alarm device occupies but very small space and may be conveniently carried in a pocketor any receptacle, such as a grip or suitcase.

In Fig. 7, I have shown a modified means for attaching my burglar alarm to-the alarm initiating or starting part which in this case is'the key 43. In this form a supplemental part tel is provided which clamps to the spring arms a2 and has a key guide portion e6 which fits over the key and serves to support the alarm device in the set position when the key is in a horizontal position with the door locked. It will be manifest that any attempt toturn the key from the opposite side of the door bymeans of tools or instruments, or to dislodge the key will result in setting off the alarm.

in the modification shown in Fig. 3, l have provided a supplemental member i8 adapted to be interposed between the window sash 49 and sash cord 51 and to be attached to the latter. This member has a pair of outstanding ears between which the spring arms 4-2 will be engaged. It will be manifest that when the window is moved, the member 48 will'be tilted, thereby setting off the alarm.

It is believed that the foregoing conveys a clear understanding of the objects prefaced above, and it should be understood that changes might be made in details of construction without departing from the spirit and scope of the invention as expressed in the appended claim.

I claim:

A burglar alarm comprising an alarm- {sorunding device including a ,bell and a striker, a spring-actuating member adapted to be held in a set position in which to prevent operation of said striker, a trip'member for holding said spring member in said set position and having recesses on opposed sides of said member, whereby upon movement in eithergdirection said spring member will enter one of said recesses and release the striker so that it will be free to sound the alarm.

ARCHIE J. SHIMP.

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