US 1630808 A
Description (OCR text may contain errors)
I Ma 31,1927.
Q 1,630,808 E. T. SIEGERDT ALARM DEVICE Filed Nov. 27, 1925 Z72 verzzr' Patented May 31, 1927.
UNITED STATES ERICK T. SIEGERDT, OF CHICAGO, ILLINOIS.
Application filed November 27, 1925. Serial No. 71,637.
This invention relates to alarm devices and is particularly adapted to be used in connection with wire screens.
In apartment houses, particularly on the second and third floors, it is quite common for children in playing around open windows in the summer time to press their heads against the screens in an endeavor to see something outside the apartment. In doin so, they often exert considerable force upon the screen, thereby disloding it from its fastenings and causing the screen and child to fall out of the window.
An object of the present invention is to provide a screen which will give a warning of this danger.
Another object is to provide a screen with an alarm device attached thereto which will give notice that an attempt is being made to cut the metal of the screen.
These and other objects are accomplished by this invention which is fully described in the following specification and shown in the accompanying drawing, in whichplugs with Figure 1 1S a partial outside view of a window screen embodying the invention;
Fig. 2 is a partial inside view of the same; and
Fig. 3 is an enlarged section on the line 3 of Fig. 2.
The embodiment illustrated comprises a frame on the outside of which is secured a metal wire screen 11 as by means of nails 12. A. recess 13 is preferably formed 011 the inner face of the frame 10 to which a similar metal screen 14L is secured as by means of nails 15 preferably placed near the outer edge of the screen.
Over this is placed a strip 16 which is preferably secured to the frame by means of screws 17 placed near the inner edge of the frame 10. The purpose of this will later be explained.
A metal socket 18 is carried by the frame 10 and makes electrical contact with the outer screen 11 while a metal. socket i9 is similarly carried by the strip 16 and is in electrical contact with the inner screen 14. Wires 20 and 21 are connected by suitable the sockets 18 and 19, respectively, and these are placed in series with an electrical source of current 22 as a battery, a switch 23 and an electric bell 24, or other form of electrically operated signal apparatus.
From the foregoing, it will be apparent that should a child leaning out of the window press against the inner screen 1%, this screen will be forced toward the screen 11, and when the pressure becomes great enough, will cause the two screens to make contact, thereby causing the bell 2 L to sound (assuming, of course, that the switch 23 is closed), and thus announcing the fact that the child is in danger of falling out of the window.
After a number of such stretchings of the inner screen 14, it may become somewhat loose and to tighten it I have made the ledge 13 slightly beveled so that when the screen is first stretched, it may have a tendency to stand away from the outer corner 13. To stretch the screen it, therefore, it is only necessary to tighten the screws 17 when the difference in dimension due to the beveling of the ledge 13 will cause the screen 14 to be stretched.
The inner edge of the frame 10 is preferably ridged as at 10 to prevent water falling thereon from short-circuiting the screens 11 and 14.
This device can also be used on screen doors and windows for the detection of burglars. l Vhere the screen door or window cannot readily be raised, it is common for them to cut the screen with a knife and, in doing so, the knife blade will make contact with both screens 11 and l i, thereby closing the circuit through the battery and bell when the bell 2% will be made to ring.
l'Vhile I have shown and described but one embodiment of my invention, it will be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made which do not depart from the spirit and scope of the invention as disclosed in the appended claim.
\Vhat I. claim as new, and desire to secure by Letters Patent, is:
A circuit closing device for alarm systems comprising a frame, two parallel normally separated metallic screens carried by said frame and insulated from each other, the frame having a. recess adapted to receive one screen, the bottom of the recess being inclined toward the other screen, a strip adapted to fit into said recess, and means for tightening said strip on the screen to stretch the screen.
ERIGH T. SIEGERDT.