US774385A - Automatic fire-alarm. - Google Patents

Description

No. 774,385. PATENTED NOV. 8, 1904-.

J. W. GRIFFIN. AUTOMATIC FIRE ALARM.

APPLICATION FILED MAR. 23, 1904.

NO MODEL.

"III/1111251211411?! I l //////1///// 1 1 m w "w; m

anuanl oz Qvanmm J W era yaw.

Patented November 8, 1904.

UNITED STATES P TENT OFFICE.

JOHN W. GRIFFIN, OF PAWTIUCKET, RHODE ISLAND, ASSIGNOR TO THE GRIFFIN AUTOMATIC FIR-E ALARM COMPANY, A CORPORATION OF RHODE ISLAND.

AUTOMATIC FIRE-ALARM.

SPECIFICATION forming part of Letters Patent-No. 774,385, dated November 8, 1904.

Application filed March 23, 1904.

T060 whom it may concern:

Be it known that I, JOHN W. GRIFFIN, a citizen of the United States, residing at Paw-' tucket, in the county of Providence and State of Rhode Island, have invented a new and useful Improvement in Automatic Fire-Alarms, of which the following is a specification.

This invention is an improved construction of automatic fire-alarm, the object being to provide a simple and efficient device by means of which a normally open electric circuit is closed and an alarm sounded whenever the temperature of the vicinity of the device exceeds a predetermined degree, thereby sounding an alarm and giving notice that excessir e temperature exists at the point where the mechanism is located.

Another object of the invention is to provide a device which can be attached to any suitable object or to the side wall or ceiling of a room; and a still further object is to provide a device in which the parts are exceedingly simple in construction and so arranged as to protect one another, thereby increasing the durability and efiiciency of the device.

With these various objects in view my invention consists in the novel features of construction hereinafter fully described, and pointed out in the claims.

In the drawings forminga part of this specification, Figure 1 is a perspective view of an automatic fire-alarm constructed in accordance with my invention. Fig. 2 is a vertical longitudinal sectional view of the same. Fig. 3 is an inverted bottom plan.

In carrying out my invention I employ a metallic base A,which is surrounded by a depending fiange A, and arranged upon this base A is a metallic cylinder B, preferably supported upon legs B, screws C passing upwardly through the base into the said legs B for the purpose of securely fastening the cylinder to the base. This cylinder B is open at one end and closed at the opposite end, said closed end having an aperture B through perature of 152.5 to 13O Fahrenheit. be understood, however, that this sleeve on Serial No. 199,546- (No model.)

which projects the threaded end D of the rod D, said rod extending longitudinally through the cylinder B, and is provided with a flanged cap D, which snugly fits into and closes the open end of the cylinder. A coil-spring E surrounds this rod D within the cylinder and bears at one end upon the cap D and at the other end against the closed end of the cylinder, the tendency of said spring being to project the flange-cap outwardly in the direction of the arrow shown in Fig. 2. This outward movement is checked by means of a nut F, screwed upon the threaded end of the rod D, and surrounding the rod D and interposed between the end of the cylinder and the said nut isfa fusible washer or sleeve G, made of any suitable alloy which will melt at a tem- It will washer can be made so that it will melt at any temperature desired. When the fusible sleeve or washer melts, the spring acts to project the cap D in the direction indicated by the arrow, such movement being utilized for the purpose of closing the electric circuit, which has heretofore been held open, by keeping the cap D away from the adjustable contact-screw H, carried by the bracket I, arranged upon the base adjacent the open end of the cylinder, said bracket being secured by means of a screw K, which passes upwardly through the base, said screw also serving as a connecting means for the conductor-wire L, suitable insulation M being arranged between the bracket and base and also between the base and screw, as most clearly shown in Fig. 2. Two binding-posts N and O are arranged upon the opposite end of the base and to which are connected the conductor-wires N and O, which lead to the battery and alarm mechanism. The bindingpost O is insulated from the base and is connected with the conductor-wire L upon the under side of the base, so that as soon as the fusible sleeve or collar melts the circuit will be closed by the flange-cap D coming in contact with the Having thus fully described my invention, adjustable screw H, the current being transwhat I claim as new, and desire to secure by mitted through the bracket l, screw K, and Letters Patent, is" the conductor-wire L to the binding-post O. r 1. A device of the kind described compris- The rod, cylinder, and base form the other ing a base having a cylinder arranged there- 5 part of the circuit. By having the fusible on, said cylinder and base constituting part of collar or sleeve at a point remote from the conthe circuit, said cylinder being open at one tact-points all danger of the fused mass servend and closed at the other end, said closed ing to insulate the parts and break the circuit end having an aperture produced therein, a is avoided. Another advantage of the arspring-actuated rod arranged longitudinally 55 rangement herein shown is that by turning an within the cylinder and having a threaded adjusting-screw in its bracket after releasing end projecting through the aperture in the the lock-nut H the rod D can be forced back end of the cylinder, said threaded end carryin the cylinder, projecting the threaded end ing a nut and a fusible collar arranged bethrough the end of the cylinder, so that the tween the nut and end of cylinder, an adjust- 6O fusible collar and nut can be easily arranged able contact-point arranged adjacent to and thereon. After this has been accomplished opposite the other end of the rod, said adjustthe screw H is turned back, so as to open the able contact-point being supported upon and circuit, and the lock-nut tightened for the insulated from the base, and conductor-wires purpose of holding the screw in that adjusted extending from the contact-point and base as 5 position. Thus the apparatus is quickly and set forth. easily adjusted, and all of the operative parts 2. A device of the kind described comprisbeing securely protected the device will reing a base having two binding-posts thereon, main in operative condition indefinitely. The one of which is insulated from said base, a cylmoment, however, the temperature of the viinder arranged upon the base and constitut- 7 cinity of the device reaches a predetermined ing with said base a part of the circuit, said point the collar will melt, and the spring will cylinder being open at one end and closed at immediately project the rod so as to bring the the other end, said closed end being apertured, cap D in contact with the screw H, thereby a rod arranged within the cylinder and havclosing the circuit and sounding the alarm. ing a threaded end projectingthrough the ap- 75 The base is flanged to afford ample room for i ertured end of the cylinder, a fusible collar the connecting-screws, and the base is also i and nut arranged upon the threaded end of provided with opening A to permit screws to 5 the rod, a flanged cap attached to the oppobe passed therethrough, so that the device can site end. of the rod, an insulated bracket atbe screwed either to the side Wall or ceiling tached to the base opposite the open end of $0 of aroom. The spring being contained withthe cylinder, the adjustable contact-point arin the cylinder is thoroughly protected against ranged directly opposite and in line with the dust, dirt, or any other foreign matter, and flanged cap, means for locking said contactthe cap D snugly fits the open end of the cylpoint, the conductorwires extending from 4 inder and prevents the accumulation of dust i said contact-point and the conductor-wire ex- 5 or dirt in said cylinder.

It will thus be seen that I provide a simple and efiicient 1ire-alarm-operating device capable of carrying out all of the objects herein mentioned.

tending from the base as set forth.

JOHN (iRIFFlN.

\Vitnesses:

ANDREW MULLEN, J OHN WALTON.

Images