Quick resetting apparatus

Claim 2

A sensing apparatus comprising a pair of input terminals adapted to be energized with a variable magnitude electrical quantity, a pair of output terminals, a first energizing network for said output terminals and including switching means having a control circuit connected to said input terminals and operable in response to the occurrence of a predetermined minimum magnitude of said quantity to render said energizing network effective to energize said output terminals at a first relative polarity, a chargeable device, a charging circuit for said chargeable device, said charging circuit being effective to charge said chargeable device when the magnitude of said quantity applied to said input terminals is not less than said predetermined minimum magnitude, a first discharge circuit connected to discharge said chargeable device, and means connecting said discharge circuit to said output terminals for energization thereof at a second relative polarity as a consequence of the discharging of said chargeable device.

Claim 3

The combination of claim 1 in which said quantity is of unidirectional potential, said discharge circuit includes an impedance energized by said quantity in a polarity to oppose the discharge of said chargeable device, and in which there is provided a second discharge circuit for said chargeable device, said second discharge circuit discharging said chargeable device at a rate which is independent of the rate of reduction of the magnitude of said quantity.

Claim 4

The combination of claim 1 in which said energizing network is connected across said input terminals and includes an asymmetric current conducting device connected to conduct current between said output terminals in a first direction, said network further including a potential dropping device which limits the current flow through said asymmetric device, said asymmetric device having a less impedance to current flow in said first direction than in a second direction opposite to said first direction, said impedance to current flow in said second direction being effective to Establish said second relative polarity.

Claim 5

The combination to claim 3 in which said asymmetric device includes the control element of a current actuated switch device.

Claim 6

The combination of claim 4 in which said switch device is a semiconductor solid state triode device having a control element and a pair of electrodes and which conducts between its electrodes as a consequence of the current flow through said control element.

Claim 7

The combination of claim 5 in which said triode device is a transistor having a base and collector and an emitter, said control element is said base and in which said base is connected to one of said output terminals and said emitter is connected to the other of said output terminals.

Claim 8

The combination of claim 6 in which said switching means is a Zener diode, said potential dropping device is a resistor, and an asymmetrically conducting diode is connected in shunt with said base and said emitter in a polarity to conduct through its lesser impedance in a direction opposite to the lesser impedance to conduction between said base and emitter of said transistor.

Claim 9

The combination of claim 7 in which said chargeable device is a capacitor, and said second discharge circuit includes a resistor connected in shunt with said capacitor.

Claim 10

The combination of claim 1 in which said charging circuit includes an asymmetric conducting device connected to charge said chargeable device through its greater impedance, said first discharge circuit also including said asymmetric device connected to discharge said chargeable device through its lesser impedance.

Claim 11

The combination of claim 9 in which said first discharge circuit includes a first impedance element connected to be energized with a potential proportional to the magnitude of said quantity and polarized to oppose the discharge of said chargeable device and further includes a second impedance element connected in shunt with said output terminals.

Claim 12

The combination of claim 10 including a triode semiconductor switch having a pair of main electrodes and a control electrode, said control electrode being connected to a first of said output terminals, one of said main electrodes being connected to the second of said output terminals, said first energizing network including current control means to limit the current flow between said control electrode and said one main electrode, and a third impedance element connected in shunt with said chargeable device.

Claim 13

The combination of claim 11 in which said switching means comprises a first Zener diode, said asymmetric conducting device comprises a second Zener diode, said current control means comprises a fourth impedance element, said triode switch includes a junction permitting substantially unimpeded flow of current through said energizing network and a high impedance to the flow of current through said first charge circuit.

Claim 14

The combination of claim 12 in which said first Zener diode breaks over at said minimum magnitude of said quantity and said second Zener diode breaks over at a magnitude substantially greater than said predetermined magnitude.

Claim 15

A quick resetting circuit comprising first and second conductors, a plurality of resistors, a plurality of Zener diodes, a transistor having a base and a collector and an emitter, a first control circuit connected between said first conductor and said base and including in series circuit a first of said resistors and a first of said Zener diodes, means connecting said emitter to said second conductor, a capacitor, a charging circuit connecting said capacitor between said conductors and including in series circuit a second of said resistors and a second of said Zener diodes, means connecting a third of said resistors between said conductors, means connecting a fourth of said resistors between said base and said emitter, a first discharge circuit connected across said capacitor and including in series circuit said second Zener diode and said second resistor and said third resistor and said fourth resistor, and means connecting a fifth of said resistors in shunt with said capacitor.

Claim 16

A quick resetting circuit comprising first and second conductors, a plurality of resistors, a plurality of Zener diodes, a transistor having a base and a collector and an emitter, a first control circuit connected between said first conductor and said base and including in series circuit a first of said resistors and a first of said Zener diodes, means connecting said emitter to said second conductor, a capacitor, a charging circuit connecting said capacitor between said conductors and including in series circuit a second of said resistors and a second of said Zener diodes, means connecting a third of said resistors between said conductors, means connecting a fourth of said resistors between said base and said emitter, a first discharge circuit connected across said capacitor and including in series circuit said second Zener diode and said second resistor and said third resistor and said fourth resistor, and means connecting a fifth of said resistors in shunt with said capacitor.

Claim 17

The combination of claim 14 including an alternating current network connected to energize said conductors through a rectifying device whereby said conductors are energized with a rectified electrical quantity proportional to the alternating electrical quantity flowing in said network, said network including reactance which delays the collapse of said quantity upon deenergization of said network, the magnitude of said rectified quantity normally being not greater than a first predetermined magnitude but being subject to excursions which are many times said first magnitude, said first Zener diode being effective to break over at magnitudes of said rectified quantity not less than said first predetermined magnitude, said second Zener diode being effective to break over only at magnitudes which exceed a second predetermined magnitude of said rectified quantity, said second predetermined magnitude being greater than said first predetermined magnitude, the magnitude of said fifth resistor being less than the magnitude of said third resistor and greater than the magnitude of said second resistor, first potential limiting means connected in said charging circuit for limiting the maximum potential to which said capacitor may be charged, and second potential limiting means connected between said emitter and said base and effective to limit the potential therebetween due to current flow in said first discharge circuit.

Claim 18

The combination of claim 15 in which said first predetermined magnitude is about 6.8 volts, said second predetermined magnitude is about 9.1 volts, the magnitude of the resistance of said first resistor is about 10K ohms and of said second resistor is about 2.2K ohms and of said third resistor is about 82K ohms and of said fourth resistor is about 10K ohms and of said fifth resistor is about 33K ohms, the capacitance of said capacitor is about 0.5 mfd., the potential limit of said first limiting means is about 40 volts and of second limiting means is about 1 volt.