US790124A - Burglar-alarm. - Google Patents

Description

No. 790,124. PATBNTBD MAY 16, 1905.V

J. HA-MMBRSMITH/ vBILIRGLAR ALARM.

APPLICATION vI'ILIID FEB. 18.1904.

i UNITED STATES Patented May 1e, 1905.

PATENT OEEICE.

JOSEPH HAMMERSMITH, OF CUMBERLAND, MARYLAND.

BURGLAR-ALARNI.

SPECIFICATION forming part of Letters Patent No. 790,124, dated May 16, 1905.

Application filed February 18, 1904. Serial No. 194,146.

To @ZZ whom it mln/y concern,.-

Be it known that I, JOSEPH HAMMERSMITH, a citizen of the United States, residing at Oumberland, in the county of Allegany and State of Maryland, have invented certain new and useful Improvements in Burglar-Alarms, of which the following is a specification.

My invention relates to improvements in burglar-alarms, and refers particularly to that type of such alarms known as detonating burglar-alarms. i

One object of my invention is the -provision of an alarm of the character and for the purpose stated which upon the opening of the door will instantly fire a percussion-cap or blank cartridge and in addition will hold the door and prevent it from being opened, and thus serve the twofold Vpurpose of an alarm and a door-securer.

Another object of my invention is the provision of an alarm which can be applied with ease and which will not mar or disiigure the door-frame and which will be inexpensive of production, simple and durable in construction, and thoroughly efficient and practical in operation.

With these objects in view my invention consists of' a burglar-alarm embodying novel features of construction and combinations of parts substantially as disclosed herein.

Figure l represents an elevation of a portion of a door and casing with my burglaralarm in position, the parts of the alarm being in the position they occupy before an at-l tempt has been made to open the door. Fig. 2 represents a similar view with the door held secured and the alarm having been operated or with the parts in the position they occupy when the door has been moved or partially opened. Fig. 3 represents a detail sectional view showing how the burglar-armsacts to hold or secure the door. Figs. 4 and 5 represent enlarged elevations of the burglar-alarm, taken from opposite sides to fully show the construction and arrangement of the parts of the device; and Fig. 6 represents an enlarged vertical central sectional View of the' alarm with the parts in the position they assume when the device has been operated to detonate the cap or cartridge.

The burglar-alarm proper vconsists of thev base or casting O, which is formed with the ears or lugs D, provided with an alimng opening E, and, further, with the arm F, providedl with an opening G, in which is placed a percussion-'cap or cartridge H. Fitting within the openings E is the plunger J, which has at one end the firing-point K and upon lits upper end is formed with a curved arm L, adapted to travel on the curved .way or guide M of the shell or casing N, and at the end of said guideway the shell is formed with a recess or kerf 0, in which the arm falls under the action of the spring P, having one end connected to the base-plate at Q, and the other end connected at R to the plunger. The casing or shell is further provided with an extension or flap S, formed with a pair of struck-up barbs or points T, which enter the casing or frame, and with openings to receive screws U for securing the alarm in position. This being the construction, the consequent operation may be briefly stated as follows: The parts are in position for operation, as shown in Fig. l, and immediately upon the. movement or partial opening of the door contact is made with the curved arm on the spring-plunger, and said arm is moved to the position'shown in Fig. 2, when the arm falls into the kerf or recess of the casing, allowing the spring to force the plunger down and explode the cap, giving the alarm, and the curved arm at this time is in the position shown in Fig. 3, where it engages the door and holds it from being opened further, Thus the device operates to give the alarm upon an attempt to open the door and also locks or secures the door from further opening.

It isl evident that I provide a device which will perform its functions of a burglar-alarm and door-securer in a thorough and efficient manner; also, that the device may be applied with ease and will not mark or disiigure the door or casing and that it can be produced at such a price as to commend. it as a useful, desirable, and practical article.

IOO

I claim- 1. An alarm consisting of a casing having substantially closed ends, a rod in said casing extended through the upper and lower ends thereof, a curved arm at the upper end of the rod and a hammer formed at its lower end, said curved arm having its free end in the shape of a hook for engaging and securing the door when partially opened, a spring within the casing surrounding the arm and connected to said arm and casing, the casing provided with a lower extended portion having a seat therein for a percussion-cap below said hammer; the upper end of the casing above its closed head formed with acurved inclined wall surrounding the upper end of the rod casing extended through the upperand lower ends thereof, an integral curved arm at the upper end of the rod and a hammer formed at its lower end, said curved arm having its free end in the shape of a hook for engaging and securing the door when partially opened, a spring within the casing connected to said rod and casing, an extension formed at the lower end of the casing provided with a seat for a percussion-cap in line with said hammer; the upper end of the casing above its closed end being provided with a curved inclined wall and provided with a slot at its highest point, and means for fastening said casing` to the door-frame, substantially as described.

In testimony whereof] have signed my name to this specification in presence of two witnesses.

JOSEPH H AM MERSM ITI-l.

Witnesses:

CHAs. E. M a'rz, FLOYD V. GILES.

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