US2171245A - Circuit breaking device for electrical alarm installations - Google Patents

Description

Aug. 29, 1939.- c. ROTH 2,171,245

CIRCUIT BREAKING DEVICE FOR ELECTRICAL ALARM INSTALLATIONS Filed Aug. 3, 1937 Profecf/ye Ens 0029 a l 1 7 0 0 dz 7 29. j

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Patented Aug. 29, 1939 UNITED STATES PATENT OFFICE Christian Roth, Zurich, Switzerland Application August 3, 1937, Serial No. 157,121 In Switzerland August 10, 1936 9 Claims.

An application has been filed in Switzerland on August 10, 1936.

This invention relates to a circuit breaking device for electrical alarm installations which operate with closed circuit.

For protecting doors, pendulum circuit breaking devices have already been proposed, which include a lever system stationarily carried with respect to the door to be protected, which lever system contacts at one end under pressure against the door and with its other end effects the control of the alarm contacts. Experience has shown, however, that these pendulum circuit breaking devices are very diflicult to adjust and often give rise to false alarms. Moreover, they are expensive to obtain and also to fit.

The novel circuit breaking device according to this invention differs from the above in that a contact casing, arranged in a carrier and freely swingable in two planes perpendicular to one another, is provided with a contact member standing under variable spring pressure and is inserted in the closed circuit, which contact member is electrically connected in the vertical position of the casing with the latter through a ball, which ball interrupts the circuit as soon as the casing is displaced from the vertical position.

In order that the invention may be fully understood I will now describe one embodiment thereof by reference to the accompanying drawing, in

which:

Fig. 1 is a vertical section of a circuit breaking device constructed according to the invention.

Fig. 2 is a front elevation of a carrier without the contact casing, and

Fig. 3 is a section on the line III-III of Fig. 1.

The circuit breaking device consists of a metallic cylindrical contact-forming casing 4 closed by a cover piece 5, in which is arranged and axially displaceable connecting member 8 having a radial bore 1. The connecting member 5 lies inside an insulating sleeve 8 and rests on an insulating disc 9, which itself lies on a regulating disc it. The regulating disc It is formed with an external thread so as to be adjustably insertible in the lower portion of the casing 4.

The connecting member 6 carries on a spring [I a second connecting member 52 arranged within the insulating sleeve 8 and having a contact pin it. On the connecting member 1?. is arranged an insulating disc N, which serves as a support for a spring disc it or the like, which is insulated from the casing i by means of an in" sulating disc it.

In the upper part of the casing 4 is a chamber (Cl. ZOO-54) I! in which is inserted a ball i8, which lies on an intermediate wall sloping from all sides towards the axis of the casing. At the axis of the casing the said wall is formed with a hole for the reception of the contact pin 3, which is pressed, in 5 the vertical position of the casing 4, up against the ball 58, so as to produce an electrical connection between the connecting member 6 and the casing 4. By means of the regulating disc I 0,

it is possible to adjust the pressure of the pin l3 10 on the ball |8 to any desired extent, so that even small disturbances acting on the circuit-breaking device, with the position of the casing 4 remaining vertical, cause a current interruption. This current interruption is assured in that the disl5 turbances are communicated to the connecting member l2, which in consequence of the slight spring pressure, is set in oscillation, which can only be stopped by compressing the spring II, and which lead to the breaking of the connection 20 between the ball I 8 and the contact pin l3 even if of a momentary nature only.

To the cover 5 of the casing is secured a metallic bolt l9, which is pivoted to a rotatable shaft 2| horizontally mounted in a carrier 20, consist- 25 ing of insulating material, by means of a screw 22 or the like, so that the casing 4 can swing to both sides out of the vertical position in a vertical plane through the axis of the shaft 2|. This is possible in that the bolt l9 passes through an 30 elongated hole 23 in the shaft 2|. In one end of shaft 2| is secured a screw 24 which, on the one hand, clamps a cable eye or socket 25, and, on the other hand, a tube 26 inserted in a bore of the shaft 2 35 Above the shaft 2| is arranged, parallel to the said shaft, an axially displaceable shaft 21 having a disc 28 at one end thereof. This shaft 2'! forms a carrier for an adjustable gauge pin 29 having a nut 30 and a lock nut 3|. The nut 3|] 40 serves as a stop for the compression spring 32, which tends to move the shaft 21 with the gauge pin 29 out of the carrier 20.

A second cable eye or socket 33 is secured in the carrier 20, which socket is connected on the 45 one hand by means of a cable, not shown in the drawing, to one pole of a source of current, and on the other hand by means of a cable 34 to the connecting member, 6, the latter being clamped in position by means of a clamping screw 35. 50 The cable eye 33 is thus in electrical connection with the cable eye 25 through cable 34, the connecting member 6, the connecting member l2, the ball I 8, the casing 4, the bolt l9 and the shaft 2|. The cable eye 25 is itself connected, to com- 55 plete the closed circuit, with the second pole of the source of current, by means of a cable 39 through the medium of a relay not shown.

The method of operation of this circuit breaking device is as follows: The carrier 20 is secured to a door 35, window or other suitable part, in such a manner that the head 31 of the gauge pin 29 lies on the stationary frame 38. The adjustability of this gauge pin enables the device to be easily adjusted in accordance with the thicknesses, etc. of the doors. In the fitted position the disc 28 lies adjacent the free end of the bolt l9. On any attempt to open the door without causing any disturbances, the gauge pin 29, owing to the pressure of the spring 32, remains constantly in engagement with the frame 38 and the disc 28 presses the bolt l9 and thus the contact casing 4 out of the vertical position, the ball l8 being thereby shifted out from its seat on the contact pin 53 and interrupting the flow of current.

' The improved device can, however, also be used where it is suitable also to employ tensioning wires Sea, such as are known for protecting door panels, walls, roofs, floors and the like. The tensioning wire is secured at the free end of the tube 26, so that the latter can turn the shaft 2| in either direction of rotation. The other end of the wire is secured at any suitable place. By the arrangement of guide rollers, not shown, thei'wire' can'change its direction as desired. Even relatively small forces acting on the tension wire cause, as experiments have shown, the turning of the shaft 2| and thus a swinging of the contact casing 4 out ofits vertical position so as to interrupt the current.

Further trials have shown that the circuitbreaking device functions perfectly satisfactorily without the use of tension wires, for protecting windows, doors and the like, in that the cutting out of window panes or door panels will produce disturbances or vibrations, which are sufficient to set the connecting member 52 in the contact casing in oscillation, thereby breaking the circuit.

The improved circuit breaking device is not only suitable to replace known considerably more expensive apparatus without its effectiveness being in any way inferior to these known arrangements; but it enables, owing to the small initial costs, places to be protected which would otherwies remain unprotected on account of the disadvantages inherent in the known constructions. i 7

I claim: r

1. In a circuit-breaking device for electrical alarm installations operating with normally closed circuit, the provision as one contact device in said circuit, of an insulated sleeve; a pair of connecting members for connection to one pole of a source of current carried in said sleeve; a'spring interposed between said mem bers adapted to retain said members in spaced relation one at each end of said sleeve; a contact pin on said other member said pin protruding from said sleeve and being electrically con-- nected'to said first mentioned member through said spring; and current conducting means for connection to the other pole of said current source, said means being disposed adjacent and in engagement with said pin and the dimensions of said spring being such that external vibrations transmitted to said casing cause said spring to oscillate and said pin to become temporarily disengaged from said current conducting means.

2. A circuit-breaking device for electrical alarm installations operating with normally closed circuit, comprising the sum-combination of: a swingable casing for electrical connection to one pole of a current source; a platform carried in said casing, said platform having a central perforation therein and sloping on all sides towards said perforation; a movable ball resting on said platform and in electrical connection with said. casing; and means, in said casing connecting said ball, in normal rest position of said casing, with the other pole of said source of current, whereby on displacement of said casing from its normal position, said ball becomes disengaged from said connecting means thereby breaking the circuit therethrough and on return of said casing to normal rest position, said circuit is automatically remade through said ball.

3. A circuit-breaking device for electrical alarm installations operating with normally closed circuit, comprising the sub-combination of: a swingable casing for electrical connection to one pole of a source of current; a spring-urged pin electrically connected to the other pole of said source of current, and said pin being insulatedly carried in said casing; a movable ball made of current conducting material in said casing; and means for automatically contacting said ball with said pin when said casing is in the normal position of rest to connect said pin to said casing and close the circuit, the arrangement being such that, on displacement of said casing out of the rest position, said ball is disengaged from said contact member and thereby breaks the circuit to actuate the alarm and on return of said casing to rest position, said circuit is automatically remade.

4. A circuit-breaking device for electrical alarm installations operating with normally closed circuit comprising the subcombination of: a swingable casing for electrical connection to one pole of a source of current; a spring-urged pin carried in, but insulated from, said casing for electrical connection to the other pole of said source of current; a centrally perforated platform mounted in said casing above and concentrically with the axis of said pin, said platform sloping on all sides toward said perforation; an electrically conducting ball resting on said platform so as normally to contact said pin and complete the circuit through said pin and casing, whereby on displacement of said casing from the normal rest position thereof said ball becomes disengaged from said contact pin thereby breaking the circuit therethrough and sounding the alarm and on return of said casing to rest position, said circuit is automatically remade through said ball.

5. A circuit-breaking device for electrical alarm installations for a door, window and the like, operating with normally closed circuit, comprising the sub-combination oi: a carrier member; a swingable casing, for connection to one pole of a source of current, carried by said carrier; a contact pin for connection to the other pole of said source insulatedly mounted in said casing; a slidable spindle carried on and projecting from said carrier member; a spring on said spindle urging said spindle outwardly, said spindle being normally held by said door in said carrier member against the action of said spring; a movable ball in said casing normally engaging said pin and said casing to complete the circuit therethrough, whereby on movement of said casing out of its normal position, said circuit is broken, and means for automatically returning said ball to normal pin-engaging position when said casing returns to its normal rest position.

6. A circuit-breaking device for electrical alarm installations operating with normally closed circuit, comprising the sub-combination of: a swingable casing for electrical connection to one pole of a source of current; an intermediate current conducting means housed in and engaging with said casing; a contact pin insulatedly carried in said casing; a spring for electrical connection to the other pole of said current source directly engaging said contact pin, said spring normally urging same into engagement with said conducting means when said casing is in its normal posiion and spring being so dimensioned that external vibrations transmitted to said casing cause said spring to oscillate and said contact pin to become temporarily disengaged from said intermediate current conducting means.

7. A circuit-breaking device for electrical alarm installations operating with normally closed circuit, comprising the sub-combination of: a carrier member; a rotatable shaft for connection to one pole of a source of current mounted in said carrier member; means for rotating said shaft; a casing carried by and in electrical connection with said shaft in a normally vertically depending position; a spring-urged pin for electrical connection to the other pole of said current source insulatedly carried by said casing; a movable ball made of current conducting material in said casing; and means for automatically contacting said ball with said pin when said casing is in the normal position of rest to connect said pin to said casing and close the circuit, the arrangement being such that, on displacement of said casing out of the rest position, said ball is disengaged from said contact member and thereby breaks the circuit to actuate the alarm and on return of said casing to rest position, said circuit is automatically remade.

8. A circuit-breaking device for electrical alarm installations for indicating the movement of an object such as a door and operating with normally closed circuit, comprising the sub-combination of: a carrier member; a rotatable shaft for connection to one pole of a source of current, mounted in said carrier member; said shaft having a slot therein; a depending bolt swingably carried by and electrically connected to said shaft and passing through said slot; a normally vertical casing carried by and in electrical connection with said bolt; a displaceable spindle normally held in said carrier member by contact with said door; a spring on said spindle adapted to urge said spindle outwardly from said carrier member on the movement of said door in an opening direction, to engage said bolt and swing said casing; a contact member for connection to the other pole of said current source insulatedly carried by said casing, and displaceable means in said casing adapted normally electrically to connect said contact member and said casing to close the circuit therethrough and, on the swinging of said casing out of its normal position, to break said circuit.

9. A circuit-breaking device for electrical alarm installations operating with normally closed. circuit, comprising the sub-combination of: a carrier member; a rotatable shaft for electrical connection to one pole of a source of current mounted in said carrier member; a depending tubular member carried by said shaft, said member having a hole therein for connecting to one end of a tension wire, the other end of which is connected to an external stationary object; a casing carried by and electrically connected to said shaft in a normally vertically depending position; a contact member for connection to the other pole of said source of current insulatedly carried by said casing; current conducting means in said casing, said means being normally so disposed as to connect electrically said casing and said contact member and complete a circuit therethrough; the arrangement being such that, on displacement of said casing from said vertical position, on swinging of said tubular member by displacement of said tensioning wire, said current conducting means is automatically displaced and said circuit is broken.

CHRISTIAN ROTH,

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