US 3567882 A
Description (OCR text may contain errors)
O United States Patent [1113567382  Invent r Jack Beck 3,259,709 7/1966 Hemmens 200/65 1730 Montgomery Ave., Bronx, N.Y. FOREIGN PATENTS 10453 [2!] App. No 037,783 381,530 10/1932 Great Britain 340/276  Filed May 15, 1970 Primary Examiner-Robert K. Schaefer  Patented Mar. 2, 1971 Assistant Examiner-M. Ginsburg Attorney-Sandoe, l-lopgood and Calimafde  BURGLAR ALARM SWITCH 5 Claims, 8 Drawing Figs.  U .S. Cl ZOO/61.93, ABSTRACT: A burglar alarm and i h system comprising a 340/276 switch having a unitary springlike contact element positioned  Int. Cl H0lh 3/02 Within a recess f an integral block and resiliently held  Field of Search ZOO/61.81, between two Contact screws to provide a normal, open or a 61-93; 340/276, 274 normally closed switch. One end of the contact element is substantially fixed in position or anchored in the block contacting  References Clted one of the contact screws while the extending portion is bent UNITED STATES PATENTS around in the recess to resiliently make and break contact 913,669 2/1909 Munsell 340/274 with the other contact screw.
PATENTEB MAR 2m $5 1 82 INVliN'IUR. JACK BEG l BY ydawfi AI'TORNE S BURGLAR ALARM SWITCH This invention relates to a burglar alarm switch. More particularly, it relates to an improved burglar alarm switch comprising a single integral contact element.
With the increasing number of incidents of crimes against person and property, particularly in urban areas, there has been an increasing concern by many for the protection of their home against unwanted entry by burglars or would-be assailants. One effective way to dissuade an unwanted entrant is to actuate an alarm when an unauthorized opening is made of a window or a door of the residence. The alarm when actuated serves to bring the unwanted entry to the attention of the residents and to law enforcement officials. More often than not, the would-be burglar is frightened off upon hearing the alarm.
Many types of alarm switches are on the market to actuate an alarm when unauthorized entry into the premises is attempted. These devices are generally relatively complicated and thus costly. As a result, many are discouraged from purchasing and installing such switches as a result of their relatively high cost.
It is an object of the invention to provide an improved burglar alarm switch which is simpler in construction and thus less costly to fabricate, while still providing long periods of reliable operation.
In the burglar alarm switch of the invention, a unitary resilient contacting element is partially disposed within a recess formed in an insulating block. One section of the con tacting element is wedged into contact with a first contacting member while another portion of the element is normally maintained in contact (or out of contact) with a second contact member.
The contacting element also includes a resilient tongue which extends beyond the recess and is normally urged by the window, when the latter is closed, to maintain the contacting element in its desired relation to the second contact member. When the tongue is released, such as when the-window is opened, the contacting element is moved out of (or into) contact with the second contact member to thereby open (or close) the switch.
To the accomplishment of the above and to such further objects as may hereinafter appear, the present invention relates to a burglar alarm system substantially as defined in the appended claims and as described in the following specification taken together with the accompanying drawing in which:
FIG. 1 is an illustration showing my burglar alarm switch with the switch in position;
FIG. 2 is a side sectional view of a prior art type of switch;
FIG. 3 is an exploded perspective view of the switch according to my invention; 7
FIG. 4 is a sectional view along the arrows 4-4 of FIG. 3;
FIG. 5 is a side sectional view showing the relationship of the parts of my switch with the window closed;
FIG. 5A is a view similar to FIG. 5 with the window open;
FIG. 6 is a side sectional view with the window closed of a normally opened switch; and
FIG 6A is a sectional view corresponding to FIG. 6 with the window open.
The burglar alarm switch is typically is installed adjacent to a window as illustrated in FIG. 1.. The window 1 comprises a movable window frame or sash 2 which moves within a fixed frame 3. My switch 12 is installed onto the fixed frame and comprises lead wires 13-14 connected to an alarm 11. When the window is open, the sash 2 is moved away from the contact of the switch 12 to actuate the alarm 11. It will be understood that the alarm 11 is installed in a remote location and may include a bell or other signalling element and/or may be cone connected via a telephone or directly to other alarm receivers.
The prior art type of switches used in the trade is shown in FIG. 2. The lead wires 13-14 are attached to connecting screws extending from the top and bottom positions. The contact element comprises multiple parts designated A, B, C, and
D. The tongue C resembles a V arrangement and when depressed towards the switch, the left side of the V presses on a plastic insulated button D which is attached to contact element A. Contact element A depends from the top screw, to which lead 13 is attached. Another contact B depends from the screw attaching lead 14 upwardly. Ordinarily, contacts A and B touch each other. When the button D is depressed such as upon the movement of tongue C in response to the opening of the window, contact A moves leftwardly breaking the contact between A and B, actuating the alarm.
The prior art switch shown in FIG. 2 is more complicated and expensive to make than my switch which is shown in FIG. 3. Further, my switch involves onlya single, unitary metal spring contacting element and does not require the use of a separate insulated button.
My invention comprises a body member having a single springlike contact element and a cover. The body member comprises an integral, one-piece, preferably injection-molded plastic block 20 having a recess 30 formed within the block. The recess is elongated and provides an exit opening slot 32 for the tongue or leaf of my contacting element as will be disclosed. I-Ioles 27-28 extend transversely through the block and are spaced from the recess. A cover 40 is attached to the body enclosing the recess by means of the eyelets 41-42 which respectively extend through the holes 27-28. After the cover is on, the eyelets are bent back upon themselves as shown at 41-42 of FIG. 4 to provide an enclosed and sealed switch and the tongue extends through slot 32.
I provide guide and contact posts 25-26 which are preferably in the form of screws which extend from the backwall of the block and into the central recess. These guide posts help locate and align the switch contact element to provide the normally contacting arrangement of FIGS. 3 and 5, or alternatively, the normally noncontacting arrangement illustrated in FIG. 6A. The block 20 having the recess and guide posts is thus adaptable to accommodate the spring contacting element in both the normally open and the normally closed versions, the only difference being in the initial positioning of the contact element. This provides for simplicity and uniformity in the manufacturing process and is an advantage of my invention.
The normally contacting embodiment actually corresponds to a normally open switch system when the window is secure, as illustrated in FIG. 5 and then the normally noncontacting embodiment corresponds to a normally closed switch system when the window is secure, as illustrated in FIG. 6.
Preferred alarm systems utilize a continuously closed circuit so that the alarm will be actuated whenever there is any opening in the entire circuit, whether it be in the switch 12 or in the lead connections 13-14. Leads 13-14 can extend through many detecting paths such as around windows and the like. It will, therefore, be understood that the preferred embodiment of the switch as shown in which the switch is normally closed when the window is closed, but becomes open when the window is open, as illustrated in FIG. 6.
The contacting element 60 comprises an essentially straight middle portion 64 having a lower heel 62 and a first locating portion turned back upon itself to provide a wedgable section 65. The end of section 65 presses against a stop 33 and is bent around contact screw 25 and presses against wall 34 at the point or region 34'. Thus, the end of the spring is securely held in place in the switch body and is in tension against and securely contacts screw 25. Other means may be used to locate and anchor one end of the spring in the switch body and to contact screw 25, such as a 'slot formed in the body to receive an extension of the spring. Wall 34 bears inwardly toward wall 33 to urge the entire spring body against wall 33 to enhance the wedge effect. The contact element also comprises a second extending feeler or tongue 61 which makes a V-shape when bent around at 62 with respect to the heel or the entire side 64. As illustrated in FIG. 5, upper screw 25 always makes contact with the switch element and also locates the bent around section 65 against the left inner wall 33 of the recess30 to enhance the wedge anchoring effect. It is important to note that the bent around section 65 is held wedged in place and fixedly contacts screw 25 in embodiments of the invention as shown in either FIGS. or 6. It will be noted that the lead wires 13-14 are attached to the respective screws 25-26 as illustrated in FIG. 4 for further connection to the alarm system.
I When the tongue 61 is engaged by the window and thus depressed inwardly when the window is closed, the side 64 of the contacting element is bent away from the left side of screw 26 as illustrated in FIG. 5, while in FIG. 5A tongue 61 is free and the heelof side 64 is in contact with screw 26. When side 64 is bent by tongue depression, the upper section 65 is also slightly bent but is further wedged in position to contact screw 25.
In the embodiment of FIGS. 6 and 6A, when the tongue 61 is so pulled away as the window opens, the contact is broken with screw 26 and, therefore, the switch becomes open. Here the spring's resiliency causes it to assume the position in FIG.
6A while the pressure exerted in the tongue in the position of switch depending upon whether the base 64 bears against the right or left side of screw 26. The eyelets passing through the body anchor the block and cover and also provide the openings for passing the anchoring screws therethrough.
If desired, an insulative coating may be provided on the tongue where electrical separation of the tongue'from the window frame structure is desirable.
While the foregoing description sets forth the principles of the invention in connection with specific apparatus, it is to be understood that this description is made only by way of example and not as a limitation of the scope of the invention as set forth in the objects thereof and in the accompanying claims.
l. A switch comprising an integral block having an internal recess and an exit opening communicating with said recess, and a unitary springlike contacting element disposed in said recess, first and second contacting posts extending into said recess at spaced apart locations, one end of said contacting element being anchored in said block and resiliently contacting one of said contacting posts, said contacting element having a base and a tongue extending from one side of said base and defining with said base a substantially V-shaped section, said tongue extending through said exit opening of said recess for engagement with an external member, said V-shaped section including a bent around portion to provide make and break contact with the other of said contacting posts in response to the external engagement-of said tongue.
2. The switch of claim 1, including two spaced eyelets positioned in said block spaced from said recess to receive screws for fastening said switch to a frame.
3. The switch of claim 1, in which said springlike contacting element includes a bent around extension extending from said base and wedged in position between the walls of said block defining said recess for providing resilient contact of said bent around extension with said first contact post.
4. The switch of claim 3, in which one wall of said recess includes a stop for providing support and pressure against the end of said bent around extension.
5. A burglar alarm switch system for attachment to a frame of a window comprising a switch having an integral block including an internal recess and an exit opening in communication therewith, a springlike contacting element in said recess, first and second spaced contacting posts extending into said recess and positioned relativel close to the sidewalls of said recess, said contacting elemen having a base and a first bent around extension extending from one end of said base and a tongue extending from the other end of said base and defining with said base a substantially V-shaped section, said tongue extending through said exit opening, said first extension making resilient contact with said first contact post and being wedged against said sidewalls and said first post, whereby said V-shaped section is bent around said first contact post for making and breaking contact with said second contact post.