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Publication numberUS310421 A
Publication typeGrant
Publication dateJan 6, 1885
Filing dateMar 26, 1881
Publication numberUS 310421 A, US 310421A, US-A-310421, US310421 A, US310421A
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 310421 A
Abstract  available in
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Description  (OCR text may contain errors)




. Patented Jan. 6, 1885.







QSPECIFICATIOBT forming part of Letters Patent No. 810,421, dated January 6, 1885.

(ModelJ T0 at whom it may concern:

Be it known that I, Honacn T. HELMBOLD, a citizen of the United States, residing in the city and county of Philadelphia, State of Pennsylvania, have invented a new and use; ful Improvement in Burglar-Alarms, which improvement is fully set forth in the following specification and accompanying drawings, in which- Figure 1 is a side elevation of a burglaralarm embodying my invention. Fig. 2 is a longitudinal section thereof.

Similarletters of reference indicate corresponding parts in the several figures.

My invention consists of a burglar-alarm which is operated by dropping on the floor, 850., of an apartment within which it is suspended, the same having a telescopically-connccted barrel and hammer or plunger and a cartridge or cap holder, the construction being such that the cartridge or cap is unfailingly discharged and the fire of the burning wad or paper thereof rapidly extinguished, the device being likewise simple, compact, and inexpensive, as will be hereinafter fully set forth.

It further consists of means for preventing bursting of the barrel, as will be hereinafter fully set forth.

Referring to the drawings, A represents the body of the alarm, consisting of the tube or barrel a and the plunger 1), fitted thereto telescopically, the lower end of the latter having a flange, Z), for preventing disconnection of the plunger and barrel, without, however, interfering with the sliding motions of said parts one within the other. The under side of the bottom of the plunger is provided with a spur or tooth, B, and the opposite or upper end of the plunger is formed with an eye, 0, which may be a hook or other device for the connection of a cord, 0, whereby the device may be suspended from a suitable part of a door, window, &c., to be protected.

To the lower end of the barrel a is attached a cartridge-holder, D, consisting of a tubular plug into which the cartridge or cap is inserted, the flange of the same resting on the upper edge of the plug. In the side of the plug are openings or vents c, which communicate with the longitudinal bore of the plug and arein communication with openings or vents d in the side of the barrel,at the bottom thereof. The plug is screw-threaded for connection with the threaded face on the interior of the contiguous portion of the barrel, and the bottom of the plug is formed with a head, 6, on which the alarm strikes when it is caused to fall or drop. The cartridge is applied to the holder D and the latter screwed to the bar rel. The cord 0 is connected with the door, window, &c., it being noticed that the plunger and barrel are distended. XV hen the door, &c., is opened, the cord is disengaged and the alarm drops on the floor or window-sill. The plunger or hammer Z) then descends and its spur strikes the head of the cartridge, thus discharging the same and sounding the alarm. It will be seen that the wad or paper of the cartridge or cap or fulminate thereof is impelled against the bottom of the plug, and, traveling but a short distance, is rapidly extinguished, whereby fire is prevented from falling 011 the floor and ignitingthe latter or the carpet thereon, the smoke of course escaping through thevents. Owing to the possibility of the cartridge-holder rotating during the discharge of the cartridge, and thereby partially closing the vents of the barrel, causing bursting of the barrel, the vents of the barrel are made of greater diameter than that of the vents of the cartridge holder, the vents of thetwo parts being in the same horizontal plane, so that should the holder rotate its vents move from the vents of 8 the barrel, which latter, being of the greater diameter, as has been stated, leave a larger amount of the vents of the holder uncovered than if both sets of vents were of the same diameter, thus providing vents of sufficient size to permit the rapid escape of the gas and smoke of the discharged cartridge and avoiding bursting of the barrel, the bottom of the bore of the cartridge-holder being closed by the bottom of the plug, whereby the gas and smoke are directed laterally through the vents, said face causing the extinguishment of the fire, &c., as has been stated.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. A burglar-alarm consisting of a barrel, a hammer fitted thereto telescopically, and a cartridge-holder, the hammer having its lower end provided with a spur, the barrel having a vent near its bottom, and the holder having a vent which opens into the'bore of the holder and communicates with the vent of the barrel, the bottom of the holder closing the bottom of the bore of said barrel and having eters or sizes, said holder being capable of rotation, and said Vents located in the same horizontal plane, substantially as and for the purpose set forth.

1 tridge-holder,having vents of diflerent dianire HORACE T. HELMBOLD.

a striking-head, substantially as and for the XVitnesses: purpose set forth. JOHN A. WIEDERsHE'IM,

2. In a burglar-alarm, the barrel and ear- 1 A. I. GRANT.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US6085458 *Dec 31, 1997Jul 11, 2000Gau; Larry J.Lawn edging
Cooperative ClassificationG08B15/00