Abstract: Disclosed herein is an electronic timing circuit which can be incorporated in an accelerator pump timing control, also disclosed herein. The timing circuit is adapted to be connected to the first and second power terminals of a DC supply and for energizing a load, for example, a fuel pump solenoid valve, during a predetermined timed cycle. The circuit includes a thyristor having an anode-cathode path adapted to be connected to the load so that when the thyristor is rendered conductive by a trigger pulse applied to the gate, current flows from the DC supply through the thyristor to energize the load and start the timed cycle. A transistor control circuit including a transistor connected in series relation with the anode-cathode path is operable for controlling the energizing current flow through the thyristor, subject to a relaxation oscillator included in the timing circuit.

Abstract: This disclosure is directed to SCR charging or other energy-switching circuits provided with priming and carrier sweep-out networks and the like that normally incur energy losses in the priming and sweep-out processes, wherein such losses are obviated by transferring energy resulting from such processes back to the power supplies.

Abstract: A trip indicator circuit for a circuit interrupter of an electric power system, which includes an electromagnetic status indicator, having an indicator which is movable between an indicating position and a non-indicating position, a pulse-actuated set coil for moving the indicator to the indicating position, and a pulse-actuated reset coil for moving the indicator to the non-indicating position. An indicator set circuit for energizing the set coil is connected across the trip coil by an electronic switching device which is rendered conductive by an overcurrent sensing circuit whenever a particular abnormal condition occurs in the electric power system, so that the set coil will be energized only when the circuit interrupter is tripped during the occurrence of the particular abnormal condition. A reset circuit is connected across the closing coil to energize the reset coil each time the circuit interrupter is closed.

Abstract: A portion of the apparatus, which requires low voltage DC energy for its energization, is connected in series with an SCR between a single pair of input or energizing terminals. A series RC circuit is connected across the SCR, and the junction within this series circuit is connected through a zener diode to the gate of the SCR. When low voltage DC is applied between the input terminals, it turns on the SCR continuously and effectively appears across the noted apparatus portion to properly energize the latter. When high voltage AC is applied between the same input terminals, it turns on the SCR for only a predetermined part of each cycle of the AC. This part is made to be such that the resulting voltage across the noted apparatus portion is effectively the same when the high voltage AC is applied between the input terminals as it is when the low voltage DC is applied between the same input terminals.

Abstract: A control circuit is provided for a contactor which has a pair of contacts and an actuator coil which is energizable under the control of a switch to cause the contacts to close. The control circuit provides a temporary path for energizing the coil and a permanent path through the contacts. The control circuit delays energization of the coil for a preselected time to allow switch contact bounce to cease. The control circuit prevents a reestablishment of the temporary path for preselected time after the contacts close.

Abstract: Control apparatus includes a power supply, a switch and first and second apparatus for connecting the switch to the power supply. The first apparatus is changeable between a first operating condition at which power flows from the power supply to the switch and a second operating condition at which power flow from the power supply is blocked. The second apparatus changes the first apparatus from the first operating condition to the second operating condition. The control apparatus includes apparatus for energizing the second apparatus in response to the switch being open.

Abstract: A remote control wiring system is provided which includes a transformer for providing power to a low voltage subsystem which, through relays, controls the opening and closing of higher voltage load circuits of the remote control wiring system. A plurality of relays are provided, one for controlling each of the load circuits. A first circuit includes in series a first solid state switching device, such as a suitable transistor, SCR or triac, and a relay, or a plurality of relays connected in parallel. Similarly, a second circuit includes in series a second solid state switching device, such as a suitable transistor, SCR or triac, and the relay, or the plurality of relays connected in parallel. A two-position switch is incorporated in the low voltage subsystem in association with the first and second circuits.

Abstract: A separate electronic switch controls energization of each of a plurality of parallel connected electromagnetic targets. An additional electronic switch controls energization of a circuit breaker trip solenoid. The individual trigger circuits for each target switch are common with the trigger circuit for the trip solenoid switch, such that a trigger signal to any one of the target switches is also applied to the solenoid switch to achieve concurrent, but independent energization of the associated target and the trip solenoid.

Abstract: An improved high security locking apparatus is provided by combining an electromagnetic locking apparatus of the type which includes a lock portion and a removable key portion, the key portion providing a determined unlocking combination signal, the lock portion providing an immediate unlocking function in response to the presentation of the determined unlocking combination signal from the key portion while placed within a determined surface location of the lock portion, with an interlocked time delay circuit which provides silent, time delayed activation of the unlocking function in response to the simultaneous presence of the determined unlocking combination signal with the placement of the key portion within the determined surface location, and which inhibits the unlocking function for all other conditions.

Abstract: A fail-safe time delay circuit comprising a detection relay for sensing the presence and absence of an input signal, a switching relay for assuming a first and a second condition in accordance with the presence and absence of the input signal, and a programmable unijunction transistor oscillating circuit, a silicon controlled rectifier gating circuit and a d.c. making circuit including a solid-state Colpitts oscillator and half-wave rectifier controlled by the second condition of the switching relay for providing a predetermined time delay period between the disappearance and the reappearance of the input signal prior to permitting the switching relay reassume its first condition.

Abstract: Energization of a motor is controlled by a latching relay operated by switch means passing current from a capacitor to the winding of the relay. The capacitor is charged through a relatively large impedance unipolarity input.

Abstract: This invention comprises a fusible resistor in a solid state relay comprising two solid state switches connected in parallel with each other, but in series with a load and a source of current. When the first of the two switches is switched on, the second switch also switches on, and conducts, supplying sufficient current to the load, thus reducing the voltage across both switches to that of the voltage drop across the second switch. Should the second switch fail to become turned on when the first switch is turned on, there will be a higher voltage across the first switch (and the components in series with it, if any) causing excessive current to flow through the first switch, resulting in its overheating and possibly fire, particularly if the switch is encapsulated. By providing a fusible resistor in the circuit of the first switch, the fusible resistor will open at such time and disconnect the first switch from the circuit, preventing a possible fire or possible damage to adjacent equipment.

Abstract: An electromagnetic flush control setup employed in a flush toilet comprising an inducing terminal, an amplifier coupled with a trigger circuit, and an electromagnet setting. The inducing terminal is placed beneath the ringed cover of a flush toilet whereby to induce therein, in accordance with the variation of electrostatic field, a small signal which is then amplified, transduced and rectified to drive a relay so as to charge a capacitor from a DC source. And subsequently with vanishing of the signal, the charged capacitor reversely discharges whereby to initiate a SCR making the electromagnet work and exert up the outlet valve of water box. Upon exhaustion of the capacitor, SCR and electromagnet repose thus accomplishing the flush process.

Abstract: A switching device for the indirect activation and/or termination of systems operatively coupled to the switching device which includes an inductor adapted to be periodically pulse energized, an armature movably mounted with respect to said inductor so as to assume a first and a second position relative to the inductor thereby causing a distinct variation of current flow in the inductor when energized by a periodically applied pulse, a manipulative armature positioning means and an associated electrical circuit responsive to current flowing in said inductor. The members are arranged such that the circuit is adapted to selectively indirectly actuate an external system only when said armature assumes one of said positions and a periodic energizing pulse has reached the inductor.