US2144472A - Resonant control relay - Google Patents

Description

Jan. 17, 1939. R. J} EY 2,144,472

RESONANT CONTROL RELAY Filed Sept. 16, 1936 WITNESSES;

INVIENTOR Q Fay-J. Wan/L y MN 7 BY ATTJEY Patented Jan. 17, 1939 UNITED STATES PATENT OFFICE RESONANT CONTROL RELAY Vania Application September 16, 1936, Serial No. 101,008

1 Claim.

My invention relates to remote control systems of the type in which superposed frequency currents are applied to an alternating current power line for the purpose of controlling translating devices such as street lights, meters, or off-peak load apparatus.

Various systems of this nature have heretofore been proposed in which a bimetal or other thermal element is utilized to distinguish between I.) a comparatively short application of the superposed frequency currents and a longer application, in order to effect opening and. closing operations by means of superposed currents of the same frequency. In general, however, the rel3 ceiving apparatus of such systems requires a comparatively large amount of superposed frequency energy in order to directly effect the operation of the thermal element or of an electromagnetic relay.

20 It is, accordingly, an object of my invention to provide a novel remote control system of the type indicated above, in which the receiving apparatus shall require a minimum amount of superposed frequency energy.

Another object of my invention is to provide a novel electronic device for use in remote control systems of the type indicated above.

A further object of my invention is to provide a novel electromagnetic relay for use in such so systems.

Other objects of my invention will become evident from the following detailed description taken in conjunction with the accompanying drawing in which;

35 Figure 1 is a diagrammatic view in perspective of an electronic device utilized in the practice of my invention.

Fig. 2 is a diagrammatic View of a remote control system embodying my invention.

40 Fig. 3 is a fragmentary elevational view of a modification of the electronic device shown in Fig. 1, and

Fig. 4 is a diagrammatic view of a remote control system employing the electronic device 45 shown in Fig. 3.

Referring to Fig. 1 in detail, a base plate I, of suitable insulating material, is provided for supporting an electronic device 2 and a magnetic system consisting of an L-shaped bar magnet 3 50 and an electromagnet 4.

The electronic device 2 may be secured to the base plate I by means of a socket pin connection of the usual type (not shown). The electromagnet 4 is secured at the midpoint of its 55 magnetic circuit to the bar magnet 3 by any suitable fastening means (not shown), and the latter is supported from the base plate I by any suitable means, such asa bracket 5.

The electronic device 2 comprises a sealed envelope 6 having a filling of a suitable gas such as neon or argon at low pressure, and a sealed-in stem 1 of glass which acts as a support for the electrode structure in the usual manner. A block 8, of magnetic material, is secured by means of a rigid support to the stem I. The block 8 is centrally slotted to support a resilient reed 9 of magnetic material.

The reed 9 is centrally spaced between a pain of laminated pole tips ID of magnetic material, the inner faces of which are provided with electrode plates I2 of suitable metal such as thorium. The pole tips ID are supported by means of a suitable rigid supporting member II from the glass stem I.

The block 8 is so positioned with reference to the bar magnet 3 as to provide a polarizing magnetic bias for the reed 9. The reed 9 is so spaced with reference to the electrode plates I2 that for the gas pressure existing in the envelope 6, and with normal voltage applied between the reed 9 and plates I2, no discharge takes place if the reed 9 is in its central position. However, if the reed 9 is vibrated from its central position, a discharge occurs to the nearest plate I2 which is interrupted at zero value of line voltage.

Referring to Fig. 2, the main power line is indicated at I3 and the source of superposed frequency currents at I4. It will be understood that the power line I3 may be an alternating current feeder or load circuit, and the source I4 may be located at any suitable point, such as a transformer sub-station.

The electronic device 2 is connected to energize a thermal relay I5, of special construction, for controlling the translating devices such as lamps IS.

The relay I5 comprises a pivoted armature I'I biased by means of a spring I8 to an open position as shown. The armature I I may be attracted to a closed position, in which the translating devices It are connected to the main power circuit I3, by means of an electromagnet I9.

The armature IT in its open position is arranged to maintain a bimetal spring 2| under tension. The bimetal spring 2 I, as shown, is normally straight and is arranged to be curled upward when heated for a sufiicient length of time by a resistance heater 22. The bimetal spring 2 I,

in its deenergized or straight position, is arranged to latch the armature IT in its closed position. When heated, however, the bimetal spring 2| curls upward to a position clear of the armature I1, and permits the latter to fall open if the electromagnet I9 is deenergized.

The electromagnet 4, associated with the elec tronic device 2, is connected in series with a suitable condenser 23 to form a resonant circuit therewith having a natural frequency the same as that of the superposed carrier. The reed 9 of the electronic device 2 may also have the same natural period as the superposed carrier, or may have a natural frequency which is a harmonic or a sub-multiple of the superposed carrier frequency.

The operation of the apparatus shown in Fig. 2 may be set forth as follows: Upon operation of the transmitter I4 to supply carrier current to the line 13, the reed 9 commences to vibrate under action of the electromagnet 4. Upon vibration of the reed 9 the electronic device 2 becomes periodically conducting, and the discharge current thereof energizes the electromagnet l9 and theheater 22. Upon energization of the electromagnet [9, the armature l-l moves'to its closed position, and. the bimetal spring 2| snaps into its straight position latching the armature closed. A circuit is now completedfor the translating devices It. If the carrier frequency is discontinued after a' short time interval, the bimetal spring 2i is not heated sufficiently to curl upward to its release position, and-the armature l1 accordingly remains latched in its closed position.

Whenit is desired to disconnect the translating devices it, the carrier currents are again applied for a much longer intervalr Upon application of the carrier currents the electronic device 2 again becomes conducting, and the electromagnet l9 and heater 22 are energized from the line 13. As

the armature I! is already in its closed position, the energization of the electromagnet I 3 has no effect. the bimetal-spring 2|, causing the latter to gradually curl up to a position in whichit is clear of the-armature I1.

interrupted. This causes deenergization of the electromagnet l9, but the bimetal spring 2| re-- mains in its upper position because of the heat stored in its own mass. The armature l'l' accordingly, isfmoved-to its open position by the spring i8. As the bimetal spring 2!, cools. it

I-Iowever, the heater 22 acts upon After a suitably long time interval, the carrier frequency currents are ever, to a pair of igniter elements 25, so that it may engage one or both of the latter upon vibration. A pair of pole tips 21 are mounted on either side of the magnetic reed 9. The pole tips 21 are arranged in the magnetic circuit of an external alternating current electromagnet 29. A cylindrical cathode 33 is supported in a position surrounding the reed 9 so as to complete a discharge path with the latter. In this modification no permanent magnetic bias is provided.

The igniter elements 25 are connected to an external inductance 3| in such manner as to complete a circuit through the latter upon their engagement with the reed 9. In this modification, upon vibration of the reed 9 a make-andbreak connection-is established through the inductance 3|, and a high induced voltage is applied to a very short film of gas between the igniter element 25 and the reed 9. The electronic device, accordingly, becomes periodically ionized, and-the main'discharge-t'akes place between the reed ii and the cathode 33; The operation of' the arrangement shown in Fig; 4 is otherwise the same. as that of Fig. 2, and will be obvious from the above.

I do not intend that the present inventionshall be restricted to the specific structural details, arrangement of parts or circuit connections hereinsetforth, as various modifications thereof may be eifected without departing from the spirit and scope'ofmy invention. I desire, therefore,.that only such limitations shall be imposed as are indicated in the appended claim.

I. claim as my invention:

An electronicdevice responsive to alternating currents comprising a sealed envelope having a gaseous. medium therein; a pair of stationary principal electrodes in said envelope, a magnetic reed mounted in said envelope for vibratory movement-along-a path substantially perpendicular tothe long axisof saidreed said magnetic reed having a principalrelectrode providing two anodecathode discharge paths ofvariable effective length depending upon the position of said-magnetic reed, electromagnetic means responsive to saidalternating currents for vibrating said reed, said electromagnetic means including an alternat-- ing current electromagnet: external to said envelope butincluded in a magnetic circuithaving an air gap portion traversing said magnetic reed substantially along said path, and unidirectional magnetic energizing means including a magnetic member-external to said envelope and included in a second magnetic circuit, said second magneticcircuit having a portion substantially following the long, axis of said reed.

ROY J. WENSLEY.

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