US2665342A - Alarm switch - Google Patents

Description

A. H. VADNAIS Jan. 5, 1954 ALARM SWITCH Filed July 24, 1950 INVENTOR l/ez /7. Vadnazs a nm down

[A gr Patented Jan. 5, 1954 UNITED STATES PATENT OFFICE 6 Claims. 1

My invention relates to an improvement in alarm switch and deals particularly with a type of switch that can be used in banks and institutions of this type equipped with manually operable burglar alarms.

Various types of switch mechanisms have been employed for setting off burglar alarms. One of the difiiculties involved with switches of this type lies in the fact that if they are accidentally actuated, considerable expense and difiiculty is usually involved. Such burglar alarms are often connected to suitable mechanism in the police department to immediately warn this department that the bank is being robbed. As a result the various branches of the police service are immediately alerted and considerable trouble and expense is involved. Usually when an employee of the bank accidentally actuates the alarm switch, the employee will refuse to admit doing so for fear of being blamed for the trouble and expense.

The object of the present invention is to provide a burglar alarm switch which includes a pair of switch buttons both of which must be actuated in order to produce the alarm. The switch buttons are mounted on opposite sides of a switch casing so that it is difiicult to accidentally actuate both switches through accident. Furthermore, the switch buttons are so mounted that they will stay in depressed position when actuated, thereby making it immediately visible to the employee if one of the buttons is accidentally depressed.

A feature of the present invention lies in the provision of a switch which may be actuated by a pair of spaced switch operating push buttons. These push buttons are slidable into the casing or into a suitable tubular guide extending into the casing. The buttons are provided with substantially conical ends, only the tapered portion of which proiects from the housing or tubular guide when the button is depressed. As a result it is impossible to easily pull the button outwardly or to manually reset the button after it has been depressed.

A further feature of the present invention lies in the fact that the conical ends on the switch operating push buttons leave a lasting impression upon th fingers of the operator for a substantial time after the switch has been actuated. The switch buttons do not move inwardly easily. Substantial inward force by the fingers is necessary in order to depress the buttons. The pointed ends on the buttons engage into the fingers and leave a depression which remains on the fingers for at least thirty minutes after the switch has been actuated. As a result it is impossible for an employee to actuate the alarm with the fingers without making it possible by examination to determine which employee was responsible for the act.

A further feature of the present invention lies in the fact that the switch buttons are preferably oiT-set out of longitudinal alignment. An opening is provided in the casing opposite each of the plungers which actuate th switches. As a result a suitable tool may be inserted into the casing to engage against the end of each plunger in order to reset the plunger into its normal operating position.

These and othe objects and novel features of my invention will be more clearly and fully set forth in the following specification and claims.

In the drawings forming a part of specification:

Figure 1 is a perspectiv view of the switch showing the outward construction thereof.

Figure 2 is an elevation view of the switch with the front cover plate removed.

Figure 3 is a sectional view through one of the switch mechanisms, the position of the section being indicated by the line 3-3 of Figure 2.

Figure 4 is an elevation view of the switch mechanism the outer nclosure being shown in section showing the switches in depressed condition.

Figure 5 is a rear elevation view of the switch mechanism, the outer enclosure being shown in section.

The switch is indicated in general by the letter A. The switch A is provided with a rear closure plate ID, a front closure plate l i, and a rectangular sleeve like body [2 connecting the front and rear closures. The sleeve !2 includes a top wall !3, a bottom wall M, and parallel side walls [5 and I6.

A threaded aperture I! is provided in the rear closure plate I!) and is designed to accommodate an anchoring bolt l9 which is designed to hold. the switch assembled. The switch may be held in place by means 20 on the connecting bolt IE, or may be held in place by suitable screws or bolts extending through the apertures 2! in the rear panel H1.

The switch casing encloses a pair of spaced switches which are connected in parallel. Each switch includes a threaded tubular sleeve 23 having a collar 24 near one end thereof to which an angle bracket 25 is secured. The sleeve 23 extends through the top panel 13 of the switch enclosure and is held in place by a suitable nut 26 or other such device. A button 21 is slidably supported in the threaded sleeve 23. The button 21 is limited in its outward movement by a pin 29 which extends through the button at a point spaced from the lower end thereof. As indicated in the drawings, the upper end of the button 21 is conically shaped as indicated at 30.

The angle bracket 25 is provided with a horizontal flange 3! to which the collar '22 is attached. This flange 3| is provided with an aperture aligned with the aperture through the sleeve 23 so that the push button 2'! may slide freely therethrough. The angle bracket 25 is similarly provided with a downwardly extending flange 32 which acts as a support .for apart of the switch mechanism. Insulated from the bracket by a suitable insulator I provide a spring arm 35. The spring arm 34 extends upwardly parallel to the bracket flange 32 and is bent at its upper end to extend through an aperture 35 in the bracket flange 32. The forwardly and downwardly projecting portion 36 of the spring 3% forms a hump S1 in the path or" movement of the button 27.

A U-shaped contact 39 is spaced from the spring arm 36-, by insulator means 40. This bracket 39 includes a pair of upwardly extending flanges ll and 42 connected by horizontally extending flange 53. The flange d2 supports a suitable contact which is engageable with the spring arm 37 and normally in the path of movement thereof.

It will be seen that if one side of an electrical circuit is connected to the spring arm 34 and the other side of the circuit is connected to the U-shaped bracket 39, a circuit is closed when the lower extremity d3 of the spring arm 36 is in engagement with the contact on the bracket flange A2. However, when the button .21 is pressed downwardly the spring arm 34 will be urged to the left as viewed in the figures from the position shown in Figure 3 to the position shown in Figure 4. As will be noted in this position the circuit is broken through these two contacts. The upper end of the flange ll of the bracket 39 serves as a means of connection with the conductor Al i while an out-turned lip 45 on the spring arm 3d forms a means of electrical connection with this side of the circuit. The lip 45 is laterally ofi-set from the U-shaped bracket 39 so as to hold these elements electrically spaced.

The lower switch mechanism is identical with that previously described. The threaded sleeve 36 extends through the bottom wall 14. A collar 4! on this sleeve engages against the inner surface of the panel it, while a nut 49 engages against the outer surface thereof to hold the sleeve in place. An angle bracket 50 is connected to the collar ll in any suitable manner. This angle bracket es includes an aperture through which the push button 52 may extend. The vertical flange 5 5 of the angle bracket 59 acts to support a spring arm 5 5 which is insulated from the angle bracket by an insulator 55. The spring arm 5 includes an upwardly and forwardly extending arm 56 having a bump or forward projection 5i thereupon. The upper extremity 59 of the spring arm 56 supports a contact cooperable with a contact on the flange 60 of the U-shaped bracket 6!.

The U shaped bracket 5! is supported by the vertical flange 53 of the U-shaped bracket and is insulated from the spring arm 55 by an insulator I52. The arm 54 extends through an aperture 63 in the bracket 56 and the hump 5! extends in the path of movement of the push button 27.

It will be noted that the push buttons 21 and 52 are provided with conical outer ends 30 and 64 respectively. As the push button 52 is moved upwardly, the spring arm 5 is urged away from the contact or flange 69], thereby opening the circuit.

As indicated in Figure 5 of the drawings, the two switches are connected in parallel. As indicated in this figure, a conductor M connects the U-shaped bracket 39 with the U-shaped bracket 6!. A similar conductor 65 connects the rearwardly extending projection d5 of one spring arm 3 5 with the projection 65 on the spring arm 55. Thus the circuit may be closed through either of the switches and as long as one switch is not actuated, it remains closed. The alarm circuit is of a type which must be broken to actuate the alarm. When both switches are actuated the spring arms 34 and 5 are both spaced from their respective contacts and the circuit is completely broken. At this point the alarm is actuated.

As indicated in Figure 1 of the drawings, an aperture 61 is provided in the top panel iii in alignment with the push button 52. A similar aperture 69 is provided in the bottom panel H5 in alignment with the push button 21. These apertures 6? and $9 are designed to accommodate a resetting tool Hi illustrated in dotted outline in Figure 4 of the drawings. This resetting tool comprises an elongated shank having a head H at its ou'ter'end by means of which the shank may be actuated. By dropping this shank it through the aperture 67 until the end of the shank engages against the top end of the push button 52, this push button may be pushed downwardly into its usual position shown in Figure 3 of the drawings. Similarly by inserting the tool through the aperture 69 and pressing upwardly upon the lower end of the push button 21, the button may be manually reset from the position shown in Figure 4 to the position shown in Figure 5.

My device has been found extremely eiiective for its intended purpose and has been found difficult to operate accidentally. At the same time, the device may be readily operated whenever it is necessary. The fact that the push buttons stay depressed provides an indication of which switch was actuated. Furthermore, to prevent false alarms the ends of the push buttons provide a lasting impression in the fingers which remains a suflicient length of time so that the switch operator may be detected by examination.

In accordance with the patent statutes, I have described the principles of construction and operation of my burglar alarm switch, and while Ihave endeavored to set forth the best embodiment thereof, I desire to have it understood that obvious changes may be made Within the scope of the following claimsv without departing from the spirit of my invention.

I claim: 7 l

1. An alarm switch including a support, a pair of switches secured to said support, said switches being connected in parallel, separate means for actuating each switch, said means including a pair of push buttons having outer finger engaging ends, said push buttons, when depressed, remaining in depressed switch actuating position until manually reset, and manual resetting means engageable with the inner push button ends.

2. The construction described in claim 1 and including pointed conical outer ends on said push buttons.

3. A burglar alarm switch including a housing, a pair of switches supported in said housing and electrically connected for parallel operation, a pair of push buttons slidably supported by opposite ends of said housing, said push buttons beirv off-set out of longitudinal alignment, each of said push buttons cooperating with a switch to actuate the same, each switch including a resilient part frictionally engaging its push button in depressed position, each of said push buttons normally remaining depressed when once depressed, said housing having openings therethrough in longitudinal alignment with each of said push buttons, said openings being designed to accommodate a push button resetting device capable of engaging the inner push button ends.

4. An alarm switch device for use in alarm circuits, the device including a casing, a pair of switches mounted within said casing and electrically connected for parallel operation, and means for actuating said switches, said actuating means including a push button cooperable with each switch to actuate the same, the push buttons being off-set from one another in the casing, means frictionally engaging said push buttons upon depression thereof, and push button guides encircling the outer ends of said push 6 buttons in depressed position whereby said outer ends cannot be engaged for retraction.

5. The construction described in claim 4 in which the housing is provided with openings therethrough in alignment with said push buttons so as to accommodate a push button resetting device.

6. An alarm switch including a casing, a pair of tubular guides supported in ofiset relation on opposite sides of said casing, a push button axially slidably supported in each tubular guide, a spring having cam means in the path of movement of each push button, cooperable contacts opened and closed by movement of each spring by its corresponding push button, said push buttons having ends which retract into said tubular guides when in depressed position so that said push buttons cannot be pulled outwardly, said springs holding said push buttons frictionally engaged in depressed position, said casing having openings therein spaced from said push buttons to admit an instrument for pushing the push buttons outwardly.

ALEX H. VADNAIS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 342,549 Ward et al. May 25, 1886 1,170,063 Heeney Feb. 1, 1916 1,337,217 Gillingham Apr, 20, 1920 1,531,606 Grebe Mar. 31, 1925

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