Abstract: This invention provides an electronic switch for model cars to prevent incapability of the remote operation of the model cars.Keeping the manual switch 10 for a given period at ON state, a receiver 4 and a battery 5 are connected, and after a provisional OFF state of a manual switch 10, it is reset in ON state for a given period, to disconnect an electrical connection between the receiver 4 and the battery 5. For this sake, even if the manual switch 10 is abruptly changed over to OFF state upon abut to an obstacle during a run of the model car, the electrical connection between the receiver 4 and the battery 5 is not disconnected, as far as a given period continuation of the OFF state of the manual switch. With a use of the switching circuit 13, ON/OFF change over is provided without using a mechanical contact, which provides no anxiety of the disconnect of contact caused by the vibration.

Abstract: A switching device insertable between an electric outlet and a load closes and breaks a circuit between the outlet and the load at certain points of time or in accordance with other predetermined conditions. The switching device is built up from a circuit board or a similar device which supports a substantial part or all circuits of the device. First connectors for connection to an outlet which provides a supply voltage are arranged perpendicular out from one side of the circuit board. Second connectors for outputting the supply voltage are arranged perpendicular out from an opposite side of the circuit board. The first and second connectors are centered about a same axis and are mounted at locations about the axis by substantially right angles in relation to each other, whereby input and output parts under tension on the board are located at maximum distance from each other with smallest possible board size.

Abstract: A back-up device includes at least one back-up battery, in particular a rechargeable battery which can be charged via the power supply, and a control unit. The control unit connects the back-up battery when the actual value of the DC voltage is less than a predefined minimum value, generates a predefined back-up time period and disconnects the back-up battery again, cyclically, after this time period has elapsed. The device has the advantage that the return of the output DC voltage of the power supply can be identified effectively without major complexity. The loads continue to be supplied both in the event of a failure of the supplying input voltage and in the event of a failure of the power supply, since the output DC voltage, which is essential for the loads, of the power supply is monitored. The device can be connected additively downstream of a power supply, without any intervention in its design being necessary.

Abstract: A system for controlling power application to an electronic component during a hotswap operation. A chassis contains a plurality of slots for interfacing with electronic components, each slot having an associated timing device. The electronic component contains a delay mechanism, such that when the electronic component interfaces with a slot in the chassis, the delay and timing mechanisms interact to create a slot timing circuit. The slot timing circuit interfaces to a ramp-up switching circuitry to produce a controlled application of power to remaining circuitry of the electronic component. The timing mechanism may be a resistor and the delay mechanism may be a capacitor, such that an RC circuit is formed which controls, in a time delayed fashion, a switching mechanism which in turn controls ramp-up of power application to the electronic component.

Abstract: An apparatus for preventing peripherals from back powering a host computer is disclosed. The apparatus use a timer and associated logic circuitry to determine the time period between signals being sent to the host computer from the peripheral device. Under predetermined time-out conditions, the current output by the peripheral is disabled to prevent the peripheral from back powering a main computer.

Abstract: A switching device of the type that can be placed between electric outlet and a load and is provided with a switch and electronic circuits including a programmable control device in order to close and break the circuit according to predetermined conditions. This is not provided with any external mechanical or electromechanical means for setting, and the conditions for switching and time adjustment are fixedly built in or programmed. In one embodiment moreover functions for switching and time setting are controlled by an optic or acoustic sensor connected to the control device. Hereby, a compact structure and a simple but reliable function is obtained.

Abstract: An internal device contained in an electronic device includes a housing, a part of which has a step portion; and a fan provided in a vicinity of the step portion, so that a space is provided as a pathway for an air flow generated by the fan, a part of the space having a boundary defined by the step portion of the housing when the internal device is positioned in the electronic device.

Abstract: A self-contained programmable wall switch actuator/timer unit can easily be mounted directly onto the outside of the face plate of a standard wall switch. This actuator/timer unit can be programmed to operate the lever of the wall switch in accordance with a program that automatically repeats on a diurnal, weekly or other cyclical basis. It comprises a small battery, a miniature electric motor with a gear/linkage mechanism operable to engage with and to move the switch lever between its OFF and ON positions, and a quartz-clock-based programming means having programming intput keys and time display means. Once programmed by way of the programming input keys, the programming means is operative to actuate the electric motor in such manner as to move the switch lever into its ON and/or OFF position in accordance with the keyed-in program.

Abstract: A precautionary timer for installation in a kitchen range, as a replacement of a plug-type fuse protecting one of the heating elements of the kitchen range. In a first aspect of the invention, the precautionary timer comprises a threaded fuse stock having first and second electrically conductive terminals set apart from one another, and conductive segments mounted inside the threaded fuse stock and connected to the first and second terminals. A timing unit comprising a low voltage solid state timer and an electronic switch is also mounted inside the threaded fuse stock. The solid state timer is powered by a current transformer sampling power from the current flowing in one of the conductive segments. The semiconductor switch is connected in series with the conductive segments and the first and second terminals, for selectively electrically connecting and disconnecting the first and second terminals to and from one another.

Abstract: A timing device for television that controls television viewing by interrupting the input signal, or input signals, to a remote television during a predetermined time or times of day. A user selects and manually presets the timer to automatically close or open an internal switch that alternately connects and interrupts transmission of an input signal, or input signals, to a remote television.

Abstract: A power supply device for a communication apparatus includes a main power supply for supplying electric power to respective units of a communication apparatus main body, a main power supply control unit for ON/OFF-controlling the main power supply, and a battery for supplying electric power to the main power supply control unit. When the main power supply is ON, the main power supply control unit receives power supply from the main power supply. When the main power supply is OFF, the main power supply control unit receives power supply from the battery.

Abstract: A system for controlling power application to an electronic component during a hotswap operation. A chassis contains a plurality of slots for interfacing with electronic components, each slot having an associated timing device. The electronic component contains a delay mechanism, such that when the electronic component interfaces with a slot in the chassis, the delay and timing mechanisms interact to create a slot timing circuit. The slot timing circuit interfaces to a ramp-up switching circuitry to produce a controlled application of power to remaining circuitry of the electronic component. The timing mechanism may be a resistor and the delay mechanism may be a capacitor, such that an RC circuit is formed which controls, in a time delayed fashion, a switching mechanism which in turn controls ramp-up of power application to the electronic component.

Abstract: A time delay relay circuit of the present invention includes a power supply terminal, a relay having a first terminal connected to the power supply terminal, and a timing circuit, for activating the relay for a preset duration, having a supply input for receiving power for the timing circuit. Also included is a means for connecting the supply input of the timing circuit to the power supply terminal during operation of the timing circuit and activation of the relay and disconnecting the supply input of the timing circuit from the power supply terminal during non-operation of the timing circuit. The means connecting the supply input to the power supply terminal may be a switch which is closed and opened to start the preset duration time running within the timing circuit. During the preset duration, the switch remains open. The relay is closed making a connection between the power supply terminal and the supply input.

Abstract: A device is provided for interrupting the power supply to an object and is characterized in that it has elements (1, 2, 11) for effecting at which time the power supply shall be interrupted. The device is particularly adapted for use in connection to electrical stoves, as its function is such that accidents occurring because of overheating of stove plates or setting of fire to foodstuffs and the like used in connection to use of the stove can be avoided, and an obvious advantage in comparison to conventional stoves is thus obtained.

Abstract: A timing control switch includes a timer control device and at least a timer adapter electrically connected with an easy accessible and convenient position of an electrical cord of an electrical appliance. The timer adapter has a receiving chamber, two electrical terminals for electrically connecting with two broken ends of the electrical cord, and a movable conducting device with a contact element which is normally kept in contact with the two electrical terminals. The timer control device includes a timer control circuitry for timing control, a connector with two electrical conduct elements, a driving device for driving a driver to move in linear direction so as to drive a connecting bridge electrically connected or disconnecting with the two conduct elements, and battery for providing power supply to the timer control circuitry and the driving device.

Abstract: A drapery actuator to open and close draperies and the like, comprising a housing and a drive pulley supported by the housing to engage a drapery cord. A motor is supported by the housing for reversibility rotating the drive pulley to move the drapery cord between a first extreme position and a second extreme position. A first electrical switch is operatively connected to the motor and a second electrical switch is also operatively connected to the motor. Switch actuator cooperate with the drive pulley such that the first electrical switch is actuated when said drive pulley moves the drapery cord to the first extreme position and the second electrical switch is actuated when the drive pulley is reversibly rotated by the motor to move the drapery cord to the second extreme position whereby when the drapery cord is in the first extreme position and the second extreme position the motor is deactivated and the drapery cord ceases moving.

Abstract: An arrangement for driving actuator coils for two or more driven devices employs a microprocessor or similar controller and an actuator driver circuit. The actuator driver circuit controls two or more relay actuator coils from a single microprocessor output terminal. This output terminal can provide a high, low, or pulse output signal. An amplifier switching device, such as a transistor, whose base is coupled to the output terminal of the microprocessor, drives the first relay actuator coil as its load. A rectifying diode is connected to one end of a capacitor and thence through a negative resistance device to a second relay actuator coil or other driven device. The coil impedances are selected so that the second coil has a significantly higher impedance than the first coil. When output pulses appear at the microprocessor output terminal, the transistor switch pulses on and off, and thus energizes the first coil.

Abstract: A power sharing device is disclosed, having a primary utility in supplying power to automotive block heaters or other auto warming devices at a user selectable duty cycle of 12.5% or 25%. In a first mode, power is supplied to 4 outlets in a sequential manner, for 15 minutes each. In a second mode, power is supplied to the 4 outlets in a sequential manner, for 7.5 minutes each, followed by a period of 7.5 minutes in which power is not supplied. The user may elect to initiate a delay period, that is selectable between 1 and 2 hours, to precede the sequence of power distribution, allowing time for the car to cool before the power cycles begin. A test circuit, activated by a pushbutton, allows a user to distinguish between the periods of time when power is not being supplied to an outlet as a part of the sequential sharing of power between outlets and a circuit malfunction, such as a blown fuse.

Abstract: An outdoor electrical outlet protector (10) comprising a waterproof extension cord (12). A timer (14) is electrically built into the waterproof extension cord (12), which will safely connect an outdoor electrical outlet (16) to exterior Christmas lights (18) and exterior security lights (20) on a building (22).

Abstract: The present invention relates to a circuit for integrating a local switch and a remote-control switch, primarily comprising a remote-control circuit, a first trigger circuit, a second trigger circuit, an integrating unit and a power circuit, in which the integrating unit further comprises two timer circuits, a local switch detecting circuit, a switching circuit and a power supplement circuit. When the circuit described above is in an initial state, in the event of the local switch does not operate within a certain time period, the control priority belongs to the remote-control circuit. When a user controls a load by remote control, the remote-control circuit will send a signal to reset the local switch detecting circuit and to make the output signal of the remote-control circuit be the control source of the switching circuit directly.

Abstract: A home appliance such as an air conditioner, refrigerator, television, or tape recorder, includes a drive element, a controller for controlling the drive element, and a manual input panel for enabling a user to input a drive signal for driving the drive element. A counter counts a time interval following the inputting of a drive signal to delay driving of the drive element until a predetermined time period has elapsed. If no counter signal is input driving the predetermined time period, the drive element is driven.

Abstract: A stove timer and automatic cut off system is provided including a stove having a plurality of burners each adapted to generate heat upon the receipt of power. A start switch situated on the stove is adapted for transmitting a start signal upon the depression thereof. A timer selector switch assembly is situated on the stove and has a plurality of discrete modes. The switch assembly is adapted to transmit a timer signal representative of a unique predetermined amount of time in each mode. An indication means is situated on the stove and is adapted to alert a user only during the actuation thereof. A relay is connected between the burners of the stove and a source of power. The relay is adapted to supply the burner with power only when actuated. Finally, a control mechanism serves to function in an activated mode only upon the receipt of the start signal wherein the control means actuates the relay.

Abstract: A light switch cover plate with a mechanical timer mechanism that includes a linear rack member for engaging the existing light switch actuator and that includes a cover plate member defining a timer mechanism cavity wherein the linear rack member is slidably installed within the timer mechanism cavity and guided along a predetermined path between a fully upward position and a fully downward position by an upper rack guide and a left and right lower rack guide, the linear rack member being biased toward the fully downward position by a helical spring attached between the linear rack member and the cover plate member, the linear rack having gear teeth formed along a side edge thereof in meshing relationship with a spring loaded mechanical drive mechanism including a spring drive assembly, a spring drive gear, a reduction gear assembly and an anchor escapement gear, the spring loaded mechanical drive mechanism providing a resistance against movement of the linear rack toward the fully downward position under th

Abstract: A device for controlling a switching relay to deliver power to a load. The switching relay selectively couples a hot leg of a utility power supply to the load. The load is coupled to a neutral wire of the utility power supply. The device includes a sensor for detecting whether an area is occupied. If the sensor indicates that the area is occupied and the load is powered off, the device monitors the line voltage for a zero crossing. Upon detecting a zero crossing, an amount of time to a subsequent zero crossing is measured and stored. Then, the device waits the amount of time between zero crossings, less a delay time for closing the contacts of the relay, and initiates a closing of the contacts of the relay. Similarly, when the sensor detects that the area has not been occupied for a predetermined amount of time and the load is powered on, the line voltage is monitored for a zero crossing and a time to a subsequent zero crossing is measured and stored.

Abstract: A low voltage power inverter utilizes reed switches to control a number of display tubes. The reed switches are controlled by magnetic coils or permanent magnets. The magnetic coils receive a control signal from a control circuit. The control circuit is powered by a capacitor coupled around a power lead and a capacitor coupled around a return lead. The permanent magnet is coupled to a mechanical actuator.

Abstract: A closed loop control system for controlling the temperature of a heated substrate is presented. In the preferred embodiment, the closed loop control system is implemented substantially or completely on a single substrate. The closed loop control system comprises means to reduce or eliminate parasitic feedback in the control system. In one aspect of the present invention, the mechanism for reducing the effects of parasitic feedback comprises a mechanism to prevent minority carriers from collecting around the base of the temperature sensing device. The mechanism for preventing minority carriers from collecting around the base of the temperature sensing device can be one or more guard rings which attract the minority carriers and prevent them from collecting around the base of the temperature sensor.

Abstract: A key handling circuit for a switching matrix having row and column conductors includes bidirectional drives for the row conductors and the column conductors. The row drive and the column drive are in a low conductive condition except when a relevant key switch is activated. The row drive provides a current input for the column drive in one phase of operation and the column drive provides a current input for a row drive in a second phase of operation.

Abstract: The disclosed input circuit incorporated in semiconductor integrated circuit device will not be operated erroneously due to fluctuations of a supply (or reference) potential caused by noise, for instance.

Abstract: A transformer, typically a miniature transformer, to provide low-voltage power between, usually, 2 to 12 V from a power network has an auxiliary winding (6) inductively coupled to the core (9) of the transformer. A reference signal is provided from the power supply, and a monitoring circuit (32), which includes a difference-forming circuit (16) is coupled to receive (a) a signal from the auxiliary winding (6) and (b) the reference signal, the difference-forming signal providing an output in dependence on the state of magnetization of the core, by evaluating differences in magnetization (.DELTA.B) depending on whether power is being supplied by the transformer, or not. A circuit interruption element (10), typically a transistor, is serially connected between the power supply (1, 2) and the transformer.

Abstract: A microprocessor controlled automatic transfer switch is provided with an improved voltage sensing scheme which utilizes an open-delta transformer and a control routine for determining voltage level or phase loss. The invention requires only two transformers for sensing three-phase power. An actuator protection feature is also provided to limit the duration of power applied to and to protect the actuator solenoids on the automatic transfer switch. Also provided are improved diagnostic annunciation features which provide specific information regarding switch position and sensing element and/or actuator malfunction.

Abstract: A control device for controlling the time sequence activation of a wall mounted toggle switch is mounted directly to the toggle switch cover plate. The device is then programmed to turn the switch on and off in accordance with the programmed entry instructions. A sliding plate within the device contacts and moves the toggle into its on and off position in accordance with the program. The housing of the device defines an opening large enough for the toggle to be manually manipulated without removal of any components of the device.

Abstract: A power source adaptor employing a small switch to securely and positively turn on and off the power source, and which can be detachably connected to an electrical apparatus. To avoid the cost and excessive size associated with prior art power source adaptors, the adaptor can include an auxiliary switch element provided for the control section of an electrical switching element to selectively start and stop a switching operation. A switch operating button on an adaptor housing operates the auxiliary switch element. An insulated coupling bar is also provided through which the switch operating button is mechanically coupled to the power on/off operating button on the apparatus body.

Abstract: Power supply system having a buffered intermediate voltage which is supplied by an auxiliary voltage source in the event of failure of a principal voltage source, there being generated from the intermediate voltage by comparison with a threshold value a digital failure signal which both controls the auxiliary voltage source and is used to form a final failure signal.

Abstract: An inside case made of rubber is mounted in an outside case, a substrate integrally provided with an engine stop switch circuit and a switch electrode of an engine stop switch unit is assembled in the inside case, and its lower side is filled with curable insulating base material to be sealed. Further, a switch contact opposed to the switch electrode is formed of pressure sensitive conductive rubber, and a reversal spring is further interposed on the pressure sensitive conductive rubber. As a result, wirings are eliminated, a decrease in the size of the entire apparatus and simplification can be realized, and a metal contact is eliminated to improve durability.

Abstract: An automatic lighting controller applies a turn-off control signal to a gate controlled power switch for switching OFF lighting when a timer circuit determines that motion activity above a threshold level has not occurred within the controlled area during a prescribed interval. A counter produces a grace period count signal and a reset count signal, with the grace period count signal occurring within a predetermined sub-interval, for example, one count cycle prior to the reset count signal. The grace period count cycle (N-1) interval is adjustable, for example, from about 0.6 second (for test purposes) to about 14 seconds. The grace period count signal enables an audio transducer which provides an audible alert that the lights are about to be switched OFF automatically. A person in the controlled area can override the impending automatic shutoff simply by initiating some motion activity during the grace period.

Abstract: An overdrive circuit having a first current source which supplies an overdrive current and a second current source which supplies an ordinary current smaller than the overdrive current. A first circuit operates the first current source that supplies the overdrive current for a predetermined time period after the start of current supply. A second circuit stops the action of the first current source after the predetermined time period has passed and drives the second current source to supply the ordinary current as the driving current.

Abstract: There is disclosed a two-wire (series connectable) delay-on-release timer apparatus for air conditioner compressor motors or the like which is connectable in series in one side of the alternating current circuit with a low voltage alternating current source, a thermostat switch with a shunt resistor acting as an anticipator heater and a relay, or other control, for applying power from the power main to an air conditioner compressor or the like. The timer includes a full-wave rectifier circuit with output connected to an adjustable time delay digital timer and also connected to a gated thyristor whereby turning the thyristor on greatly reduces electrical impedance between the input terminals of the rectifier circuit. A digital timer IC is provided with circuit elements for sensing the difference between thermostat switch closed and thermostat switch open conditions.

Abstract: Connection of batteries to the DC bus lines across which capacitors are connected in power systems, such as uninterruptible power systems, is carried out using an auxiliary switch which is controlled to connect the batteries to a DC bus line through a precharge resistor momentarily before connection is made through a main connector. The preconnection of the batteries through the precharge resistor provides a controlled rate of charge of the capacitors before closing of the main connector to thereby avoid excessive surge currents. When the main connector is opened, as when the power system is prepared for transportation or long term storage, the auxiliary switch interrupts the current path from the battery through the precharge resistor and provides a current path from the DC bus line through a discharge resistor to ground to bleed down the charge on the capacitors to a desired level within a selected period of time.

Abstract: The power control system includes a time controlled bi-stable device for causing at least one slave outlet to be controlled in response to a master unit being energized and/or de-energized. The system thus enables the slave outlet only to be energized, and not the master unit, if the master unit is energized, and then de-energized within a short predetermined time interval. Advantageously, the system of the present invention can be controlled remotely by using a conventional remote control device for a television receiver, and the audio from the television receiver is transmitted through the audio receiver. Thus, by using only the remote control device, either the television receiver can be used with the audio receiver, or the audio receiver can be used independently under the control of the television remote control device.

Abstract: The present invention provides a switching device incorporating a simple circuit capable of avoiding the flash-on of a transistor when a power supply is turned on and off thereby reducing the OFF delay time. The output circuit comprises a FET (145) having a drain and a source connected in series to a current line for supplying a current from a power supply (VD) to an output detector (load) (L), and a photocoupler (149) for applying a driving voltage across the gate and the source of the FET (145) according to the output of an internal circuit (151), a differentiation circuit comprising a capacitor (7) and resistors (5,9) is connected across the drain and the source of the FET (145), and second transistor (3) having a collector and an emitter connected to the gate and the soruce of the FET (145) is driven by a charging current for charging the capacitor (7).

Abstract: An electrical control system for sensing instantaneous total electrical power consumption being delivered into a facility and for interrupting selected electrical current consuming loads within the facility when the total incoming current consumption exceeds one or more preselected maximum level for a continuous first preselected time period. The system utilizes existing power transmission lines within the facility to sequentially transmit at least two pulsed digital shut down signals on each of at least two phases or legs of transmission lines within the facility to one or more remote shut down units at the end of the continuous time period. Each remote unit then interrupts electrical power to at least one electrical load within the building for a second preselected time period, after which power is restored to the electrical load until the total current consumption again exceeds one of the preselected maximum load levels continuously for the first time period.

Abstract: The invention relates to a load drive circuit which is able to detect an "on" fault of a switch element for controlling power to a load, and reliably interrupt the load current. A monitoring sensor is provided which generates an output when energy is supplied to the switch element of the switch circuit from outside the circuit, and a received signal level of the energy is a high level with the switch element "off", but does not generate an output when a received signal level of the energy is a low level with the switch element "on". Through logical processing of the output of the monitoring sensor and a load drive signal for driving the switch element, using a logical sum operating circuit and a self-hold circuit, the relay contact points can be prevented, at the time of an "on" fault of the switch element, from following the load drive signal, and from "hunting".

Abstract: A switch circuit for activating and deactivating a motor vehicle cruise control includes a 555 model timer integrated circuit which has a trigger terminal, a reset terminal, a threshold terminal, a control voltage terminal and an output terminal. A substantially constant voltage is applied to the threshold terminal. A first normally-open switch connected between the vehicle ground and the trigger terminal, and a second normally-open switch connected between vehicle ground and the reset terminal. Separate pull-up resistors connect the trigger and reset terminals of the timer to a positive voltage source and a capacitor couples the control voltage terminal to vehicle ground. A relay has a coil connected between the output terminal and vehicle ground, and has a switch that is connected between the common terminal and the ON control terminal of the cruise control. The 555 timer is configured as a latching circuit having an output which toggles in response to operation of the two normally-open switches.

Abstract: An electronic control for gas furnaces controls a two speed main blower fan and an induction draft fan based on 24 volt input signals from a room thermostat, a high limit and an ignition control including a gas valve. The input signals are coupled to input ports of a microprocessor through current limiting resistors and to AC ground through pull down resistors. AC ground is also connected to the IRQ port of the microprocessor. Output ports of the microprocessor are connected to a relay driver which in turn is connected to relays for energizing and de-energizing the fans. The control calibrates itself on a continuing periodic basis to read the AC inputs synchronously at the peak of their wave and can switch the relays asynchronously based on the Real Time Clock of the microprocessor or can be switched synchronously by providing a selected delay so that contact engagement and disengagement occurs at or near the zero crossing of the AC line voltage wave form.

Abstract: A combination comprises an EAS tag having an exteriorly accessible channel and a releasable lock for securing the tag to an article, the lock being disposed at a given distance along the channel, and a detacher for detaching the tag from the article, the detacher including a probe adapted for movement in the passage, a drive unit energizable for moving the probe in the channel, and timing circuitry for controlling energization of the drive unit such that the drive unit moves the probe through distance corresponding to the given distance. The timing circuitry controls energization of the drive unit to move the probe through a distance corresponding to the given distance in a first sense for disposing the probe in releasing engagement with the lock. The timing circuitry controls energization of the drive unit to move the probe through a distance corresponding to the given distance in a second sense for moving the probe from engagement with the lock means to the exterior of the tag.

Abstract: A range extender module for extending the range capability of a barrier control system comprising a low voltage AC control unit which receives low voltage AC control signals conveyed by wires to input terminals thereof from a plurality of remotely located switches and responds to such AC control signals by controlling the barrier. The controlled barrier may be, for example, a garage door or a driveway gate. The range extender module is inserted into the wires between the low voltage AC control unit and the remote switches and includes a source of DC voltage, which is used to energize the formerly AC energized switches and responds to DC input signals created by operator interaction with the switches by selectively gating low voltage AC control signals to appropriate input terminals of the low voltage AC control unit for controlling the barrier.

Abstract: An electronic delay turn off switch including a bridgelike array of four diodes disposed between an alternating current power source and a load wherein the diodes have anodes and cathodes in opposing disposition and having an SCR with anode connected to the interconnected cathodes and with cathode connected to the interconnected anodes. A gate isolation diode, a switch, a resistor-capacitor charge mode timer, and a DIAC are interconnected between the SCR anode and gate thereby providing an SCR turn on whenever the switch contacts are closed, and a delayed SCR turn off whenever the switch contacts are opened. In an alternate embodiment a variable resistor is added to enable user selection of the duration of turn off delay.

Abstract: An electrical appliance comprises a power supply cable (70) having a first conductor (200) surrounded by a second conductor (210) for supplying electrical power to the appliance from a domestic electricity mains supply, and a connector (490) connected to cable for detachably connecting the conductors of the cable to first and second voltage signals of the electricity mains supply. In operation, the second conductor (210) is connected to the lower of the voltage signals. The second conductor (210) thus acts as a shield in opposition to electric fields radiating from the cable. The shield improves in efficiency as the lower mains voltage signal approaches Ground potential.

Abstract: A programmable switching unit which may be incorporated in a switch for installation in a standard switch box, or into a single or multi-adaptor for connecting one or more appliances to a wall outlet, the unit being switchable between a first, learning mode, in which it updates a table of transitions between ON and OFF states of a controlled appliance over a first period, and a second, automatic mode in which it replicates the memorized transitions over a subsequent period or periods. The first period is preferably longer than the subsequent period or periods.

Abstract: A time delay switch for use with an electrical load and a source of electrical power, including a multiple-position toggle switch and a user-programmable microchip. The toggle is movable among three positions: an "OFF" position, an "ON" position on one side of the OFF position, and a "TIMER" position on the other side of the OFF position. The toggle is biased from TIMER to OFF so that, whenever it is moved to TIMER, it returns to the central OFF position. When the toggle is moved to TIMER, an electrical signal is sent to the microchip that (1) starts a clock for a preselected period of time and (2) permits electricity to flow through the switch as though the toggle was in the ON position during that time. Alteratively, the microchip can be programmed to start passing current after the preselected period elapses. Thus, the device can be used to turn a light or other electrical load off after a user-determined period of time, or to turn the load on after a preselected time.