US2545854A

US2545854A - Fire alarm switch

Info

Publication number: US2545854A
Application number: US147782A
Authority: US
Inventors: Levy Morris
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-03-06
Filing date: 1950-03-06
Publication date: 1951-03-20
Anticipated expiration: 1968-03-20

Description

March 20, 1951 LEVY 2,545,854

FIRE ALARM SWITCH Filed March 5, 1950 Patented Mar. 20, 1951 UNITED STATES PATENT OFFICE 3 Claims.

My invention relates to a new and useful fire alarm station such as is used inside of buildings to cause an alarm or signal to result from the breaking of a fragile front panel.

An object of the invention is to improve the construction of devices of this character which will be exceedingly simple, strong and durable andincluding the elements of an electric circuit closer or switch capable of positively completing an electric circuit under certain conditions.

Another object of the present invention is to produce a circuit closer'for a fire alarm station including a stationary contact member and a gaged, under certain conditions, by a strong single strand spring wire movable contact member having one end secured at the bottom of the chamber and the other end projecting into a cavity behind the stationary contact member, and said approximately equal to the thickness of the fragile panel 8, such as glass, which is seated on said shoulder and held in place by securing means l 9. The securing means may be any appropriate movable contact member having an elbow intermediate its ends to be engaged by a fragile holding panel for normally retaining the movable contact in a depressed position.

With the above and other objects in view this invention consists of the details of construction and combination of elements hereinafter set forth and then designated by the claims.

In order that those skilled in the art to which this invention appertains may understand how to make and use the same I will describe its construction in detail referring by numerals to the accompanying drawing, in which-- Fig. 1 is a front elevation of a complete fire alarm station constructed in accordance with my invention.

Fig.' 2 is a section on the line 22 of Fig. 1 showing the movable spring contact depressed.

Fig. 3 is a similar view with the fragile front panel removed, as after being broken, illustrating the movable spring contact projected forwardly by its inherent resiliency to complete the electric structure detachably fastened to the body 5 and overlapping the edge of the fragile panel. As illustrative of ,a form of panel securing means I have shown rings or grommets l6 large enough for the perimetersto overlap the edge of the panel or overlie the shoulder I while the center holes are disposed beyond the edges of the shoulder and panel for the reception of screws ll threaded into the body 5.

The-back of the body may have a compartment I2 formed therein in alignment with the chamber 6 to provide a partition l3.

In the bottom of the chamber 6 or in the forward face of the partition is formed a cavity l4 which is bridg'ed'by a stationary contact member !5 preferably in the form -of a plate of good electric conductivity securely and positively fastened in place by screws l6 and H projected through the back of the body, especially the partition l3 and threaded into stationary contact member to hold it fast against the bottom of the chamber 5. The screw I! is of suflici'ent length to accommodate a'washer l8 and a conductor I9 of an electric alarm system including a signal means *front face of the anchor plate 20a sufiicient distance to accommodate the eye 25, Fig. 4, of the stiff, strong, single strand spring wire movable contact member 26 and a nut 21.

The movable contact member 26, as stated above, is formed from strong spring wire fashioned to provide the eye 25 at one end from which the wire extends outwardly and then bent back as a U-shaped loop 28 to one side of said eye with the branches of said loop in the same plane as the coil of the eye. the wire is bent outward and then inward to provide an elbow 29, the legs of which diverge, and finally the end of said wire is bent to lie in a plane parallel with the plane of the branches of the U-shaped loop 28, to from the contact terminal 30.

The movable contact member 26 is fastened to From the U-shaped loop the anchor plate 20 by placing the eye 25 over the screw 2i and screwing the nut 21 in position on said screw 2|, with the contact terminal'end 3U projecting into the cavity [4 and in back of the stationary contact member. The cavity id is of sufficient depth to allow a limited oscillatory movement of the contact terminal end of the movable contact member 26 whereby said end may be moved out of engagement with the stationary contact member i5 under certain cnditions. Also, the elbow 29 is of such dimensions that when the contact terminal end 30 of the movable contact member is in engagement with the under side of the stationary member l5, Fig. 3, said elbow 29 projects outside of the plane of the shoulder 1. Therefore, when the elbow is in or inside of the plane of the shoulder, as when retracted by the panel 8 resting on said shoulder I, the contact terminal end 3!! will be out of engagement with the stationary contact member l5, Fig. 2.

For convenience, a hook 3| may be fastened to the body 5, as at one side thereof, and one end of a fiexible means 32, such as a chain, also secured to said body 5, as by the hook, and to the free end of said flexible means is attached a hammer 33,-ordinarily suspended from the hook and used for breaking the fragile panel 8.

In order to identify the device as a fire alarm station, a paper tag 34 may be placed in back of the fragile panel 8, said tag having the word Fire or equivalent information or additional wording delineated thereon or the desired information and directions depicted in any other suitable manner.

In practice, the device is completely assembled including the mounting of the fragile panel so that the movable spring contact member is depressed or retracted, as illustrated in Figs. 1 and 2. When the station is installed, the wires l9 and 24 are connected in a circuit including a source of electricity and an alarm device, such as a bell, which is the usual custom and the body fastened to a support, such as a wall, by fastening devices, such as screws, projected through the holes 35 and into the support.

Whenever it is necessary or desirable to give an alarm the fragile panel 8 is broken by striking it with any suitable instrument, such as the hammer member 33. This will release the pressure on the movable spring contact 26 so that it can snap outwardly whereby the terminal contact end 30 will engage the rigid stationary contact member l with considerable force to immediately produce an excellent unwavering electrical connection between the two contact members.

Of course I do not wish to be limited to the exact details of construction herein shown and described as these may be varied within the scope of the appended claims without departing from the spirit of my invention.

Having described my invention, what I claim as new and useful is:

1. A fire alarm station comprising a body having a chamber in the front thereof with a cavity in the bottom of said chamber, a rigid stationary contact member imposed on the bottom of said chamber and bridging a portion of said cavity. means projected through the back of the body to secure the stationary contact in place and function as an electrical conductor, an electrical conductive anchor plate on the bottom of the chamber in spaced relation to the Stationary 00 1- tact member, a movable contact member having one end mounted on the anchor plate, means projected through the back of the body to fasten said anchor plate and the contiguous end of the movable contact member in place and a portion of said fastening means functioning as an e1ectric conductor, said movable contact member consisting of a stiff resilient section of wire fashioned to provide an eye at the anchored end from which the wire extends outwardly and then back as a U-shaped loop to one side of said eye with the branches of said loop in the same plane as the coil of the eye and the wire then bent outward and inward to form an elbow extending to the open end of the chamber and finally projecting in endwise alignment with one of the branches of the U-shaped loop as a free terminal contact end extending into the cavity in back of the stationary contact member, a fragile panel, and means to secure said panel to the body across the open end of the chamber, said panel engaging the elbow to press the terminal contact end out of engagement with the stationary contact member, said movable contact member being released upon breaking of the panel whereby the terminal contact end engages the stationary contact member to complete an electric circuit.

2. The fire alarm station according to claim 1 wherein the body is provided with a recessed shoulder surrounding the open end of the chamber against which the fragile panel rests and the means to secure said panel in place consists of rings held in place by screws projected through said rings and into the body with por tions of the rings overlapping the rim of the panel.

3. As an article of manufacture, a fire alarm station comprising a body having a chamber in the front thereof with a recessed shoulder surrounding the open end of said chamber, a rigid stationary contact member secured to the body within the chamber and spaced from the bottom of said chamber, a stiff resilient movable contact member consisting of a section of wire fashioned to provide an eye at one end and a U- shaped loop to one side of said eye and an offset elbow at right angles to the loop and a terminal contact end, said movable contact member being fixed on the bottom of the chamber by means of the eye with the terminal contact end positioned in back of the stationary memher and the elbow projecting towards the open end of the chamber and extending beyond the shoulder when the terminal contact end is in engagement with the stationary contact member, a fragile panel seated on the shoulder and engaging the elbow of the movable contact member to depress the latter to normally hold the terminal contact end out of engagement with the stationary contact member, means to secure the panel in place, and means to connect the movable and stationary contact members with opposite sides of an electric circuit.

MORRIS LEVY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 992,633 Auth May 16, 1911 2,030,799 Parsons l Feb. 11, 1936