US2989737A

US2989737A - Fire alarm apparatus

Info

Publication number: US2989737A
Application number: US853569A
Authority: US
Inventors: Theodore J Collum
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-11-17
Filing date: 1959-11-17
Publication date: 1961-06-20
Anticipated expiration: 1978-06-20

Description

June 20, 1961 T. J. COLLUM 2,989,737

FIRE ALARM APPARATUS Filed Nov. 17, 1959 2 Sheets-Sheet 1 IE" -i 2 n 38 2 l f A INVENTOR.

THEOflOEE \Z' COLLUM June 20, 1961 T. J. COLLUM 2,989,737

FIRE ALARM APPARATUS Filed Nov. 17, 1959 2 Sheets-Sheet 2 IN VEN TOR.

rAliaoaefi J (04 4 (/44 lrrale/ve v5 2,989,737 FIRE ALARM APPARATUS Theodore J. Collum, 251 Winter Drive,

Worthington, Ohio Filed Nov. 17, 1959, Ser. No. 853,569 3 Claims. (Cl. 340- 227) The present invention relates toa fire alarm apparatus.

Previously proposed have been fire alarm systems employing an electrically operable alarm which is actuated in response to the application of heat to a heat-responsive element or device. Of the commercially available systems, wired systems are more highly rated by fire protective and insurance associations. While wired systems are widely used among owners of large properties such as cooperative apartments, residential hotels, and the like, such systems generally are not popular with owners of smaller type properties such as single or duplex homes. The owners of small residences are not sufliciently impressed with the need to install fire alarm systems at the time of construction of the residence for the reason that such systems are expensive to install under most circumstances and are even more expensive to install after a residence has been completed. Additionally, if the system installed depends upon a residential house current, its reliability is depreciated.

The fire alarm systems proposed in order to avoid the expense of installation of a fire alarm system, either during construction of the residence or after construction, or in order to avoid having the alarm system depend upon the residential electric current, generally have as their source of current one or more dry cell batteries. Such batteries are prone to deteriorate in a relatively short length of time and the necessity for frequent inspection and replacement of the batteries entails not only the expense of the labor involved and the expense of the replacement of the batteries but also creates a condition of insecurity in the mind of the property owner in the event that the system is not inspected and the batteries replaced at the proper intervals.

Other fire alarm systems which have been proposed employ other means than an electric current for their actuation, siuch means including gas under pressure and the like. Such systems have not been wholly satisfactory for the reason that the alarm signal of such a system may not be remotely located and is given only at the point where the alarm is activated.

An object of the present invention is to provide a fire alarm system or apparatus which is installed with ease and facility in most residences, either during the construction thereof or after construction thereof, using relatively unskilled labor, one employing a power unit having a virtually indefinite shelf life requiring a minimum of inspection, and one which is highly effective in action.

Another object of the present invention is to provide a fire alarm system or apparatus which, through the use of optional equipment, may have an alarm which is sounded at a point remote from the apparatus or point of confiagration.

These and other objects and advantages of the present invention will be fully apparent from the following description when taken in conjunction with the annexed drawings, in which:

FIGURE 1 is an isometric view of the apparatus of the present invention as viewed from the front and one side;

FIGURE 2 is a view on an enlarged scale, taken on the line 22 of FIGURE 1, a portion of the wall of the power unit and a portion of the liquid storage receptacle being broken away;

FIGURE 3 is a view taken on the line 3-3 of FIG- URE 2;

United States Patent FIGURE 4 is a view taken on the line 4-4 of FIG- URE 2;

FIGURE 5 is a view similar to FIGURE 2, showing the alarm apparatus of the present invention in actuating condition; and

FIGURE 6 is an isometric exploded view of the lower end portion of the plunger and associated key element.

Referring in greater detail to the drawings in which like numerals indicate like parts throughout the several views, the fire alarm apparatus of the present invention comprises an upright housing 10 for mounting upon a support such as a vertical wall surface or the like. The housing 10 includes a top 12 and a bottom 14 having an opening intermediate the ends thereof closed by a bimetallic disc 16 which is supported in a resilient ring 18.

The housing 10 includes a back wall 17 and a front wall 19 having a screen panel 20 in the upper end thereof.

Side walls

22 and 24 connect the back wall 17 and the front wall 19 together and extend from the lower end of the housing 10 to the top 12.

Within the housing 10 is a power unit '26 having an open top 28. One end of the power unit 26 rests upon a shelf 30 which projects inwardly from the housing side wall 24. The other end of the unit 26 rests upon a flat head 32 on the upper end of a slidable plunger 34. The plunger 34 is slidable through holes provided in a horizontally disposed support member 36 which is fixedly secured to the back wall 17 and the front wall 19, as shown in FIGURE 3.

The shelf 30 and the head 32 on the plunger 34 supports the unit 26 in spaced relation with respect to the disc 16.

The plunger 34 constitutes means mounting the unit 26 within the housing 10 for movement relative to the top 12 of the housing 10.

A liquid storage receptacle 38, provided with a closed top 40 and a rupturable bottom 42, is superimposed upon the unit 26 so that the bottom 42 is in registry with and closes the open top of the unit 26. The closed top 40 of the receptacle 38 is adjacent to and spaced below the top 12 of the housing 10.

A hinge 44 connects one end of the receptacle 38 to the adjacent end of the unit 26 for movement of the receptacle 38 with the unit 26.

A vertically disposed force applying element or rod 46 is slidably supported in the closed top 40 of the receptacle 38 and has its lower end normally engaging the receptacle bottom 42. The portion of the rod 46 adjacent the upper end projects above the closed top 40. A frangible closure member 48, fabricated of brittle glass or the like, extends over the upper end portion of the rod 46 and forms a cap for the opening in the receptacle 38 preventing evaporation of the liquid stored therein.

The bottom 42 of the receptacle 38 is provided with a score line 50 (FIGURE 4) along which the central portion of the bottom 42 breaks when force is applied to the element or rod 46, as shown in FIGURE 5, the force being the result of raising of the adjacent end of the unit 26 and the attached receptacle 38 to the point where the upper end of the rod 46 engages the underside of the top 12 of the housing 10 and is depressed thereby, forcing the bottom 42 to break along the score line 50 and to discharge the contents of the receptacle 38 into the open top of the unit 26.

Releasable latch means is operatively connected to the plunger 34 for holding the unit 26 and the receptacle 38 against movement relative to the top 12 of the housing 10. This latch means includes opposed linkage elements 51, a head '52 on the lower end of the plunger 34, and a key element 54 resting upon the upper face of the disc 16 and slidable within the bifurcated lower end portion of the plunger 34.

Spring means is operatively connected to the plunger 34 for urging the unit 26 and the receptacle 38 to move relative to the housing top 12. This spring means consists in a coil spring 56 circumposed about the portion of the plunger 34 above the support member 36 and having one end bearing against the support member 36 and having the other end bearing against the bottom of the head 32 on the upper end of the plunger 34.

The linkage elements 51 are normally in the erect and slightly over-center position as shown in FIGURE 2. Their upper ends are pivotally connected to the under surface of the support member 36 and their lower ends are pivotally connected to the upper surface of the square head 52 which is fixedly secured on the lower end of the plunger 34. The linkage elements 51 are shifted from the over-center position to the spread-apart position when the key element 54 is forced up into the slot 33 in the head 52 on the plunger 34 and into engagement with the ears 53, FIGURE 6, provided on the linkage elements 51. When the linkage elements 51 are shifted to the spread-apart position of FIGURE 5, the coil spring 56 forces the plunger 34 upwardly, resulting in the shifting of the unit 26 upwardly, as shown in FIGURE 5.

An electrical actuable alarm '58 is mounted within the housing and is connected electrically by wires 60 and 62 to the terminals 64 and 66 of the unit 26. The unit 26 may be of conventional construction having a plurality of alternatingly disposed anode and cathode plates 68 arranged in face to face confronting relation and separated from each other by conventional materials. The unit is in a charged condition devoid of the electrolyte '70 which is stored in the receptacle 38, as shown in FIGURE 2.

In operation, upon the application of a heat sufficient to cause the bimetallic disc 16 to snap from the position in which the lower face is convex to the position in which the lower face is concave, as shown in FIGURE 5, the key element '54 will be pushed upwardly into the end portion of the plunger 34 into engagement with the ears 53 formed on the linkage elements 51, forcing the linkage elements 51 outwardly out of their normal over-center latched position, to thereby release the compressive forces stored in the spring 56 and effect the upward movement of the plunger 34 carrying the unit 26 and the receptacle 38 therewith. Upon upward movement of the receptacle 38, the upper end portion of the rod 46 strikes against the housing top 12 and the striking force is transmitted to the receptacle bottom 42, rupturing the same and permitting the discharge of the electrolyte 70 from the receptacle 38 into the unit 26, as shown in FIGURE 5.

Upon discharging of the electrolyte 70 into the unit 26, the plates of the unit 26 will be activated and current will flow to the alarm 58 to cause the latter to produce the desired signal.

The side wall of the receptacle 38 may be provided with a window as at 72 in FIGURE 3 through which may be observed a hydrometer float 74 movable in a tube 76 provided in the interior of the receptacle 38. Inspection of the interior of the receptacle 38 at frequent intervals to determine the position of the float 74 will inform the person charged with the maintenance of the apparatus of the present invention of the specific gravity of the electrolyte 70 in order to be informed of the necessity of changing the electrolyte 70 when necessary.

Although the float 74 is shown and described as a part of the invention, it is to be understood that it may be omitted without effecting the efficiency of the apparatus.

The unit 26 may have the atmosphere partially exhausted therefrom in order to preserve and prevent deterioration of the anode and cathode plates of the unit 26. Additionally, partial evacuation of the unit 26 will expedite the flow of the electrolyte 70 into the unit 26 when the receptacle bottom 42 is ruptured,

As an illustration of the use which might be made of the present apparatus in triggering a simple alarm systern, anyone skilled in the art could design a simple radio transmitter which could operate on two, four, or six-volt transistors. The optional device, positioned to the rear of the unit or below the unit, could be recessed in the usual plaster wall between upright studding with an antenna of the proper length disposed in the space below. A tuned receiving device, powered by the residential house current, could be mounted in the attic or at another point in the house, or outside serving several houses, and designed to receive an impulse transmitted by the basic unit and cause the sounding of a simple alarm, an outside alarm, a wired or radio signal to the fire department, or for other use. This receiving device, being susceptible to malfunction, could have built into it a monitoring device which, when the device is working properly, would emit an audible signal at a predetermined time each day, In the absence of such signal, the householder would know that the receiving device was not working. This would not, however, interfere with the operation of the basic unit as hereinabove described.

In order that the unit 26 accommodates itself to various voltages, it may be provided in two or more cells as found practical for the voltage output desired.

What is claimed is:

1. In a fire alarm apparatus, a housing adapted to be attached to a support and having a top, and a bottom fabricated of heat responsive material, a power unit devoid of electrolyte and having an open top positioned within said housing and spaced above said bottom, means mounting said unit in said housing for movement relative to said housing top, a receptacle provided with a closed top and a rupturable bottom and containing a charge of electrolyte superimposed upon said unit so that the rupturable bottom closes the open top of said unit with the closed top adjacent to and spaced below the housing top, means connecting said receptacle to said unit for movement with the latter, a vertically disposed force applying element slidably supported in the closed top of said receptacle and having the lower end normally engaging said receptacle bottom and having the portion adjacent the upper end projecting above the closed top of said receptacle, a releasable latch means operatively connected to said housing bottom for holding said unit and receptacle against movement relative to said housing top, and an alarm electrically connected to said unit, said latch means being operable responsive to the application of heat to said housing bottom to move said unit relative to said housing top, cause the projecting end portion of said force applying element to strike against the housing top, transmit the resultant striking force to and rupture the receptacle bottom, and permit the discharge of the electrolyte from said recepacle into said unit.

2. In a fire alarm apparatus, a housing adapted to be attached to a support and having a top, and a bottom fabricated of heat responsive material, a power unit devoid of electrolyte and having an open top positioned within said housing and spaced above said bottom, means mounting said unit in said housing for movement relative to said housing top, a receptacle provided with a closed top and a rupturable bottom and containing a charge of electrolyte superimposed upon said unit so that the rupturable bottom closes the open top of said unit with the closed top adjacent to and spaced below the housing top, means connecting said receptacle to said unit for movement with the latter, a vertically disposed force applying element slidably supported in the closed top of said receptacle and having the lower end normally engaging said receptacle bottom and having the portion adjacent the upper end projecting above the closed top of said receptacle, a releasable latch means operatively connected to said housing bottom for holding said unit and receptacle against movement relative to said housing top,

an alarm electrically connected to said unit, said latch means being operable responsive to the application of heat to said housing bottom to move said unit relative to said housing top, cause the projecting end portion of said force applying element to strike against the housing top, transmit the resultant striking force to and rupture the receptacle bottom, and permit the discharge of the electrolyte from said receptacle into said battery, and spring means operatively connected to said latch means for urging said unit and receptacle to move relative to said housing top.

3. In a fire alarm apparatus, a housing adapted to be attached to a support and having a top, and a bottom fabricated of heat responsive material, a power unit devoid of electrolyte and having an open top positioned within said housing and spaced above said bottom, means mounting said unit in said housing for movement relative to said housing top, a receptacle provided with a closed top and a rupturable bottom and containing a charge of electrolyte superimposed upon said unit so that the rupturable bottom closes the open top of said unit with the closed top adjacent to and spaced below the housing top, means connecting said receptacle to said unit for movement with the latter, a vertically disposed force applying element slidably supported in the closed top of said receptacle and having the lower end normally engaging said receptacle bottom and having the portion adjacent the upper end projecting above the closed top of said receptacle, a releasable latch means operatively connected to said housing bottom for holding said unit and receptacle against movement relative to said housing tap, and an alarm electrically connected to said unit, said latch means including a vertically movable plunger, spring means operatively connected to said plunger urging said plunger upwardly, said unit being supported on the upper end of said plunger, a bimetal disc arranged in said housing bottom, latch means normally in engagement with said plunger, said disc being operable responsive to the application of heat thereto to shift said latch means out of engagement with said plunger, and permit said plunger to move said unit relative to said housing top, cause the projecting end portion of said force applying element to strike against the housing top, transmit the resultant striking force to and rupture the receptacle, bottom, and permit the discharge of the electrolyte from said receptacle into said unit.

References Cited in the file of this patent UNITED STATES PATENTS 1,218,847 Firey Mar. 13, 1917 1,699,633 Sears Jan. 22, 1929 2,674,946 Hjelm Apr. 13, 1954 2,783,291 Gold Feb. 26, 1957 FOREIGN PATENTS 790,971 Great Britain Feb. 19, 1958 OTHER REFERENCES Germany (German printed application Yl36 'IVa/21b, Nov. 15, 1956).