Abstract: The portable engine starter for vehicle racing may be an electromechanical structure configured for use with an engine in a vehicle. As a non-limiting example, the engine may be a combustion engine. The portable engine starter may detachably couple to the engine and may be operable to start the engine. The rotation of a starting motor located within the portable engine starter may provide the motive forces used to start the engine in the vehicle. The portable engine starter may be an independently powered structure. The portable engine starter may include a housing, the starting motor, and a power circuit. The housing may enclose the starting motor and the power circuit. The power circuit may electrically connect to the starting motor. The portable engine starter may be detached from the vehicle once the engine of the vehicle is started.

Abstract: A permanent magnet drive on-load tap-changing switch including a changing switch circuit that includes an odd- and an even-numbered tap-changing circuit that are structurally identical. The tap-changing circuits include working contactors and dual-contact synchronous transition contactors made of primary contactors and secondary contactors. The working contactors and the dual-contact synchronous transition contactors directly face moving contactors. The moving contactors are connected in parallel to each other. Moving contactor permanent magnets are bijectively connected onto the moving contactors. The moving contactor permanent magnets directly face on the other extremity thereof a moving contactor driving mechanism. The moving contactor driving mechanism moves the permanent magnets.

Abstract: A permanent magnet drive on-load tap-changing switch including a changing switch circuit that includes structurally identical odd- and even-numbered tap-changing circuits. The circuits include working contactors and dual-contact synchronous transition contactors made of primary and secondary contactors. The contactors each face directly a moving contactor, which are connected in parallel. A permanent magnet is fixed on each moving contactor and face directly on the other extremity thereof a moving contactor driving mechanism. The mechanism changes a force applied to the magnets, allowing the moving contactors to come into contact with or be separated from the working and transition contactors, thus implementing changeover from one tap to another tap. The switch is structurally simple and convenient to use, obviates the need for a high-speed mechanism, implements changing by the direct actions of the contactors, operates at high speed and reliably, and has a low failure rate and an extended service life.

Abstract: Motor drive diagnostic and control methods and apparatus are provided in which rectifier and inverter switching devices are individually monitored for malfunctions, and detected malfunctions initiate implementation of a safety function to signal a drive controller to shut down non-safety-related processing, to discontinue command pulse signaling to the switching devices, and to disable optical transmitters between the drive controller and the rectifier and inverter switches, and an input contactor or other switching circuit is opened to disconnect input power from the motor drive after implementation of the safety function.

Abstract: A control circuit for a fan includes a fan controller, a switch controller, and a frequency detector. When a pulse-width modulation (PWM) signal output pin of the fan controller outputs PWM signals, the frequency detector outputs a high level signal, connecting an input pin of the switch controller to an output pin of the switch controller. The fan receives the PWM signal. When the PWM signal output pin of the fan controller does not output PWM signals, the frequency detector outputs a low level signal, such that the output pin of the switch controller does not output any signal. In this state, the fan receives a high level signal through a resistor and a power supply, enabling the fan to continue operating.

Abstract: A circuit for controlling a load current through a coil is connected to an output port of a transistor H-bridge that includes two low side transistors and two high side transistors. A current sense circuit is coupled to the H-bridge and configured to provide a representation of the load current provided by the output port. A current regulator is configured to generate a modulated signal dependent on the representation of the load current and a current set-point. The modulated signal has a duty-cycle. A gate control logic drives the individual transistors of the H-bridge on and off in accordance with the modulated signal. A direction signal provides the load current to the coil. The direction signal determines the direction of the load current. An over current detection circuit is coupled to each individual transistor and is configured to signal an over-current by providing an active over-current failure signal when a transistor current through the respective transistor exceeds a respective maximum value.

Abstract: A method for activating a jamming protection function in an electrical closing system. The jamming protection function is designed to abort a movement of a closing part in a movement direction if it is detected that the movement of the closing part is obstructed by a jammed object by: —providing consecutively measured values of a motor variable of a motor that effect the movement of the closing part, wherein the motor variable gives an indication of a drive torque provided by the motor; —determining a gradient curve from the consecutively measured values of the motor variable, wherein the gradient curve is established using a derivative method that provides for a weighting of the individual consecutively measured values of the motor variable according to the measurement sequence thereof; —establishing a point in time for activating the jamming protection function according to the determined gradient curve.

Abstract: Disclosed is a method for braking or stopping an electromotor which can be operated with direct current, such as a brushless direct current motor. If there is an error in the electromotor or in the electronic or mechanical units connected to the electromotor, the presence of definite error states is verified, and the electromotor is braked, by carrying out, taking into consideration a maximum loading capacity of an electronic control unit which is connected to the electromotor, at least temporarily, a control of the electromotor which is adapted to the detected, definite error state.

Abstract: A motor driving circuit receives a control pulse signal pulse-width modulated according to a target rotational speed, and drives a fan motor. A start pulse signal generating unit generates a start pulse signal having a predetermined duty ratio. A driving unit drives the fan motor by pulse width modulation according to the driving pulse signal received from a control unit. When the duty ratio of the control pulse signal is switched from zero to a nonzero value when the fan motor is in the stopped state, the control unit commences the driving operation for the fan motor. The control unit outputs, as the driving pulse signal, the start pulse signal, in a predetermined start period Ts from the commencement of the driving operation. After the start period elapses, the control unit outputs the control pulse signal as the driving pulse signal.

Abstract: A cooling system is provided with a motor drive device, a fan motor, and a Hall element. The motor drive device includes a lock protection circuit and a lock controller. When a control signal instructing rotation of the fan motor that is to be driven instructs stoppage of the motor for a predetermined time-period or longer, the lock controller has the lock protection circuit inactive. At an occasion when the control signal has continued to instruct stoppage of the fan motor for a first time-period or longer, a standby controller starts time measurement, and after a further predetermined second time-period has elapsed, makes at least a part of the motor drive device transition to a standby mode.

Abstract: The invention relates to a method for determining a position point of a movable element, particularly a window (33) or a roof of a motor vehicle that can be advanced into at least one elastic receptacle (36) by means of a drive, comprising the steps of continually determining a spring stiffness in relation to the moving element (33) in the elastic receptacle (36) and determining a position point upon exceeding a specified spring stiffness threshold value.

Abstract: A cooling system is provided with a motor drive device, a fan motor, and a Hall element. The motor drive device includes a lock protection circuit and a lock controller. When a control signal instructing rotation of the fan motor that is to be driven instructs stoppage of the motor for a predetermined time-period or longer, the lock controller has the lock protection circuit inactive. At an occasion when the control signal has continued to instruct stoppage of the fan motor for a first time-period or longer, a standby controller starts time measurement, and after a further predetermined second time-period has elapsed, makes at least a part of the motor drive device transition to a standby mode.

Abstract: The Objective of the present invention is to provide a delay unit for door with a door closer, which is capable of automatically closing the door after the elapse of a certain time since the door was opened and can be installed in case that the door closer is embedded inside the building and thereby being not exposed. The objective is solved by providing a delay unit 5 for door with a door closer comprising: a first sensor for detecting the door 2 opened to the first angle A, a lock unit 7 for electrically lock/unlock of the rotation of the rotation axis 3 of the door 2, a timer, a first sensor, and a control means, with which the first sensor, lock unit 7, and timer is connected, for controlling the lock unit 7 based on the signals from the first sensor and timer.

Abstract: A wiper is pivotably supported and is swung by a drive force of an electric motor. When a command, which commands execution of one of high and low speed modes, is entered through a wiper switch in the middle of operation of the wiper in another one of the high and low speed modes, a control unit controls an electric motor such that a moving speed of the wiper, which is preset for the another one of the high and low speed modes, is changed to the moving speed of the wiper, which is preset for the one of the high and low speed modes, during a time period of executing a predetermined number of swings of the wiper between an upper return position and a lower return position upon entering of the command through the wiper switch means.

Abstract: The present invention provides a control device featuring a control module featuring one or more modules configured to provide a first control signal for controlling a first device in order to open or close a second device; and also configured to respond to a change in a parameter sensed in relation to controlling the first device, and to provide a second control signal for controlling the first device based at least partly on the change in the parameter in relation to time. The first device may be a motor; the second device is a valve; and the parameter may be current. In operation, the first control signal is for turning on the motor in order to open or close the valve, and the second control signal is for turning off the motor in order to open or close the valve.

Abstract: The present invention provides wireless and direct wired methods and devices for automatically closing electrically-driven roll-down storm shutters in the presence of rain on one or more rain sensors.

Abstract: A method for controlling a motorized barrier operator after detecting an obstruction includes the steps of providing a motorized barrier operator that moves a barrier between limit positions and providing at least one control switch that upon actuation moves the barrier in a direction toward one of the limit positions. Actuation of the at least one control switch during movement of the barriers at least causes the barrier to stop. If an obstruction is detected by the motorized barrier operator during movement of the barrier, the operator allows only uni-directional movement of the barrier, regardless of actuation of the at least one control switch, after the detecting step.

Abstract: The windshield wiper system for use on a vehicle is capable of automatically adjusting the delay between consecutive cycles of a windshield wiper as a function of vehicle speed. The system includes at least one windshield wiper and a motor coupled to the windshield wiper for driving it. A sensor generates a signal corresponding to a measure of the vehicle's speed. A processor is coupled to the sensor and to the wiper motor and provides a drive signal to the wiper motor which is a function of the first signal.

Abstract: A motor control method and a motor control apparatus according to the invention supply a DC motor for a predetermined time period upon starting said DC motor with a d.c. current as an initial value current, which is smaller than a threshold value current required for a first gear coupled to a rotor shaft of said DC motor to drive and rotate a second gear in engagement with said first gear.

Abstract: There is provided an external watchdog timer 30 for detecting a temporary runaway of the microcomputer body 20 and resetting it according to a pulse output of the microcomputer body 20. Further, an internal watchdog timer 70 operated independently from a control section of CPU of the microcomputer body 20 is incorporated as a program. When a pulse signal is not outputted from the microcomputer body 20 exceeding a predetermined period of time, the external watchdog timer 30 is disabled, and impedance of the output terminal 32 is made high and the backup circuit 60 is set in an operating condition, so that the windowpane can be opened and closed by a manual operation switch 11.

Abstract: An apparatus for electronically monitoring an adjusting drive controlling a moving part in a vehicle is proposed wherein a position-dependent anti-jam system is realized. The signals of a switching strip and of an incremental sensor are considered in different manners, depending on the position of the moving part.

Abstract: A position control device for driving a movable member by a motor to a target position prevents a re-start of the motor by the vibration after stopping of the movable member. A re-start operation is forcedly inhibited during a predetermined period after a stopping operation of the movable member at the target position, and is permitted, only after the predetermined period, is entered by the position of the movable member is different from the target position.

Abstract: A transformer has its primary windings connected in series with the pumping motor and has secondary windings powering in cascade a rectifier and a voltage limiter regulating the voltage supplied to the auxiliary equipment by diverting excess current supplied by said secondary windings.

Abstract: A control circuit outputs a first signal at a predetermined period in the case of being in a normal state and in the case of not being in a normal state, stops the output of the first signal at the predetermined period and outputs a third signal for controlling a motor on the basis of a second signal at a time when a switch SW is operated. In the case that the control circuit is not in a normal state, the first signal is not output at the predetermined period, a fifth signal is output from an output circuit and the second signal passes through a second gate circuit. Then, a drive circuit drives the motor by the second signal passing through the second gate circuit.

Abstract: A circuit for operating an electric motor includes a feedback arrangement which generates a control variable signal that is supplied to a drive stage for the motor. The circuit also includes a monitoring arrangement to ascertain whether the motor is overloaded. The monitoring arrangement emits an overload signal if it detects an overload state, and the control variable signal is then reduced. In one embodiment, the monitoring arrangement detects an overload state by comparing a motor voltage signal to a motor voltage limit value which is a function of the motor current, and emits the overload signal if the motor voltage signal is smaller than the motor voltage limit value.

Abstract: There is disclosed a method of controlling an automatic door opening/closing apparatus for a washing machine that includes the steps of determining whether or not there is an error in an automatic door opening or closing operation carried out in response to a command to open or close the washing machine's door; determining if the erroneous operation has been repeated more than a predetermined number of times according to consecutive incoming commands to open or close the door; and when erroneous operation has repeated more than the predetermined number of times, ignoring a subsequent command to open or close the door.

Abstract: A power window driving control device formed of a measuring device which measures time elapsed since closing of a window glass has been designated by a switch, a sensor which detects a completely closed state of the window glass, a current detecting device which detects that current flowing to a motor when the window glass is being closed exceeds a predetermined value, and a driving control device which effects one of stopping the motor and stopping the motor after driving the motor reversely for a predetermined time, in at least one of a first state, in which the current detecting device detects that the current flowing to the motor exceeds the predetermined value and in which the completely closed state of the window glass is not detected by the sensor, and a second state, in which the time elapsed since closing of the window glass was designated exceeds a predetermined time.

Abstract: A lens controlling apparatus includes a lens-driving stepping motor, a driving current forming circuit for forming a driving current waveform to be supplied to the stepping motor, an inputting circuit for inputting a stop instruction to stop the lens-driving stepping motor, a stopping circuit for performing the operation of stopping the stepping motor in accordance with the stop instruction, a phase detecting circuit for detecting the phase of the driving current waveform to be supplied to the stepping motor, and an inhibiting circuit for inhibiting the stop instruction from being executed except when the phase of the driving current waveform detected by the phase detecting circuit is a predetermined phase.

Abstract: A moisture-responsive system for closing the windows or sunroof of a vehicle having one or more openings each closed by a power driven closure; the system having a moisture sensor for providing a moisture signal in response to the sensing of moisture; a circuit coupled to the closure and the moisture sensor for providing a signal to actuate the closure in response to the receipt of a moisture signal, the circuit including disabling features for safety purposes.

Abstract: A control system and method for a plurality of motors utilize one, and only one, motor drive unit that provides power to drive any one of the motors. The system and method also utilize a controller that controls which of the motors to energize. Power from the motor drive unit can be communicated to one of the motors selected by the controller, or power from a primary power source can be communicated to one or more of the motors selected by the controller. Sequencing of the motors to and from the motor drive unit and the primary power source, and between the two, is automatically controlled, such as based on how long each of the motors has been used. Accordingly, a method of controlling a plurality of motors comprises: defining a motor utilization criterion; sensing a parameter affected by the number of the motors that are operating; and sequentially starting and cumulatively operating ones of the motors selected in response to the motor utilization criterion and the sensed parameter.

Abstract: A method of controlling a printer using a dc motor as a drive source thereof, comprises the steps of: setting a predetermined prohibition period of time during which print and sheet-forward operations are prohibited, the predetermined prohibition period of time corresponding to a period of time until the motor arrives at a predetermined speed since the motor starts to be energized; measuring a motor power turn-off period of time until the motor starts to be energized since the motor is turned off; comparing the motor power turn-off period of time with a predetermined value; if the motor power turn-off period of time is within the predetermined value, making the prohibition period of time invalid; and if the motor power turn-off period of time exceeds the predetermined value, making the prohibition period of time valid.

Abstract: A wiper apparatus comprises a wiper switch, a washer motor, a washer switch for actuating the washer motor by its on-operation, a wiper motor actuated independently by on-operation of the wiper switch and interlockingly with the washer motor by the on-operation of the washer switch, and a controller for maintaining the wiper motor to rotate until the load applied on the wiper motor reaches predetermined value. According to this invention, the wiper blade never stops before the cleaning liquid is removed from the wiping surface by detecting frictional resistance between the wiper blade and the wiping surface as the motor load.

Abstract: A safety interlock circuit for a vacuum cleaner system is disclosed for interrupting the flow of current through conductors of a vacuum hose and handle assembly whenever an electrical attachment accessory is disconnected from the handle assembly during operation of the vacuum. A pulse-type reset circuit is also disclosed for re-enabling current flow through the conductors of the vacuum hose and handle assembly after the electrical attachment accessory has been reattached to the handle assembly. The safety interlock circuit of the preferred embodiment comprises a relay coil, a plurality of normally open relay contacts, and a current sensing resistor, all connected in series with an AC power source and a motor of the electrical attachment accessory. A voltage doubler is also connected in parallel with the current sensing resistor for supplying a DC voltage to the relay coil.

Abstract: In an electrical tool having a clutch for adjusting rotational torque of the driven shaft, a limit switch of double-throw type is used for detecting the state of the clutch, and a capacitor is arranged to be charged via the limit switch. In one embodiment of the instant invention, the capacitor is normally discharged and is charged when the clutch assumes a disengaged state, thereby producing a trigger pulse used for making a short circuit for the motor only when the capacitor is not fully charged. In another embodiment, the capacitor is normally charged, and is discharged when the clutch assumes a disengaged state, thereby producing a trigger pulse used for making a short circuit for the motor. With this arrangement a switching circuit provided for making the short circuit for the motor is effectively prevented from making the short circuit when a power switch is turned on irrespective of the state of the clutch.

Abstract: A modular power plant comprises an internal combustion engine coupled to an electrical machine. The electrical machine may be used to start the engine and to generate electrical energy. The power plant is provided with an electronic control and protection system comprising an electronic processing and control unit arranged to operate in a first mode when the power plant is used alone, and in a second mode when the power plant is used together in a coordinated manner in an installation comprising a further n power plants. In this second mode of operation the processing and control unit may act as a master unit for controlling and coordinating the operation of the processing and control units of the other n power plants in a predetermined manner, or as a slave unit controlled by another control and processing unit of one of the other n power plants. Means are provided for assigning the roll of master unit to one of the control and processing units of the n+1 power plants.

Abstract: A rotation control system including speed control feedback automatic speed control apparatus for controlling the rotation speed of a rotator to a predetermined speed, feedback automatic phase control apparatus for controlling the rotation phase of the rotator to a predetermined phase, and changeover apparatus for changing over at least one of the loop gain of the speed control apparatus and a loop gain of the phase control apparatus in a changeover period, and changeover control apparatus for controlling the changeover apparatus in association with the rotation of the rotator.

Abstract: In a well such as an oil well, a timer connects a power source to the motor which drives the well pump for timed energization and de-energization periods. The timer consists of an electronic programmable timer having a stored program data processor for processing digital information and with capabilities to variably enter time program data into the processor to selectively energize and de-energize the pump motor for any desired time intervals for each day and the time intervals for each day of the week may be programmed differently. When the pump motor is provided in the form of an electric motor, a power transducer is connected to the power source energizing the motor to continually monitor line voltage and current and provide a true power output signal representative of the phase angle between the line voltage and line current.

Abstract: An electrically operated dual motor drive system having first and second reversible traction motors (14, 16) driven by a power source (18). Motor control circuitry (10, 12) for controlling the direction of current flow through the motors (14, 16) is designed to be actuated by only two coils (36, 42). Preferably, control circuits (10, 12) employ an arrangement of normally open (32a, 32b, 38a, 38b) and normally closed (34a, 34b, 40a, 40b) contacts such that the two motors (14, 16) operate in reverse directions in the event of a complete system malfunction. A line contactor (20) is advantageously utilized to simultaneously serve as a main power disconnect for a variety of motors within the system.

Abstract: A drive and control arrangement for a mechanical eccentric press is disclosed. The arrangement includes a direct current electric motor connected to a reduction gear mechanism. An output shaft of the reduction gear mechanism is coupled to an eccentric such that the eccentric rotates with the shaft about a common axis. A connecting rod of the press is connected to the eccentric for pivotal movement about an axis parallel to and offset from the common axis of the shaft and eccentric. The arrangement includes a limit switch that is operated by a cam element adjustably mounted on the eccentric. An electronic control device is included and has a starter unit for supplying electric current to the motor, and a braking unit for short-circuiting the armature of the motor through a resistance in order to brake the motor and the press. The braking unit is actuated by the limit switch a predetermined period after the connecting rod has moved through its bottom dead center position.

Abstract: A control unit for automatically controlling the angular position of a reversible, motorized device, such as an antenna rotor, in response to a signal from an external sensor, such as a potentiometer coupled to the rotating shaft of a windvane. The unit includes integrated circuits and other electronic components for monitoring the windvane signal and for activating the rotor, as necessary, to maintain its alignment with the sensed wind direction. The unit also comprises means for providing: a no-response zone of adjustable width about the momentary, average wind direction; an adjustable, time delayed response to changes in wind direction; an automatic reversal of rotation if the rotor approaches the .+-.180.degree. position while searching for the wind direction; an automatic disabling of the rotor for windspeeds less than a selectable, threshold value.

Abstract: An electronic control means utilized in an electrically actuated shift apparatus for a multispeed axle including an electric power source and an electric motor coupled to actuate means for shifting the axle. The power source is connected to the electric motor through a shift speed control switch and a plurality of steering diodes. When the switch is actuated to select an axle speed, power is applied through one of the steering diodes to one side of the armature of the motor. Power is also applied through another of the diodes as a shift signal to a timing circuit. A first means is responsive to the shift signal for generating a first control signal for a first predetermined time. At the termination of the first control signal, the timing circuit generates a second control signal to connect the other side of the motor armature to ground thereby actuating the motor.

Abstract: A drive circuit is provided for controlling the energization of a DC motor as a function of speed to maintain the motor speed equal to a speed defined by a speed command signal. The speed command signal is summed with a velocity feedback signal to produce a speed error signal which is used as an input to a motor drive circuit. In accordance with the invention, the speed error signal is limited in order to continuously limit the current through the motor to a continuously changing maximum depending on the speed of the motor. During an initial part of the speed range, the limiting level is increased to maintain a constant maximum motor current. During an intermediate speed range, the limiting level decreases so as to sharply decrease current with increasing motor speed; and during a final speed range, the limiting level increases so as to gradually decrease current with increasing motor speed.

Abstract: Apparatus for rotating an antenna to a predetermined position and maintaining said position is disclosed. The system comprises an antenna position sensing signal source, a desired position signal source, both of which provide analog signals, position comparator means, and antenna drive means. Comparison of the desired position signal and actual position signal generates a direction relay signal and an antenna rotor drive relay signal which together activate the antenna rotor drive means for rotation in the proper direction to the desired position. Circuitry is included for automatic operation in conjunction with equipment utilizing predetermined channels, such as a radio or television receiver, and for manual override or testing and calibration of the automatic operation.

Abstract: A hoisting apparatus and a control circuit therefor comprising a reversible electric motor drivingly connected to a hoisting drum for hauling an object up and down. The control circuit includes first and second photosensitive elements each responsive to a light beam for initiating rotation of the electric motor in either direction and means for terminating rotation of the electric motor.

Abstract: A system is provided to control a load responsive to a maximum load condition to disable the load when the maximum load condition exists, the control being altered first to provide a period of non-response during load start up and secondly to provide temperature compensation over a very wide temperature range and more particularly where the load device is a motor means for linearly reciprocating a closure member such as a sun roof, a window or a door, particularly for a vehicle such as an automotive vehicle.

Abstract: A circuit breaker motor operator control circuit utilizes the voltage developed across a dynamic braking resistor during breaking of a permanent magnet DC motor to prevent re-energization of the motor until it has been braked to a virtual stop. The control circuit also includes a timing network operating to prevent continued pumping of the breaker operating mechanism by the motor operator should the operating mechanism for some reason fail to become charged within a prescribed time period.

Abstract: Disclosed is an apparatus for controlling an electric motor for driving a cooling fan of an internal combustion engine. The apparatus comprises an engine operation detecting means, a timer, an engine temperature detecting means, a logical product generating means, and a motor controlling means. The electric motor is driven only when all of the following three conditions are satisfied: the engine is not operating; a predetermined timing period initiated when the engine stops operating has not expired; and a temperature in the engine room is higher than a predetermined value.

Abstract: A sequencing control circuit is provided for a door operator motor which is connected to open and close a garage door as controlled by signals from manual switches and load switches. The sequencing control circuit includes time delay means with a first time delay period in the order of six to eight seconds. This permits a person to hold a push button switch closed for about six to eight seconds so that a slab door may be opened against a snow drift which otherwise would have so much torque requirement on the motor that an overload switch would stop the motor. Enabling means is provided to enable the motor during this time period yet to disable the constant signal from the push button for periods longer than this time delay period so that the door operator motor then is responsive to signals from the load switches.The sequencing control circuit also includes a latch circuit having an output in a feed back loop to maintain the latch circuit latched upon a momentary input control signal.

Abstract: A step structure for mobile homes and the like. A base is secured to an underside of the vehicle and serves to pivotally mount a linkage which in turn carries a pair of step rails on which a step is slidably mounted. Extension and retraction of the step involves combined swinging travel of the step surface as well as travel in a lateral direction along the step rails to achieve a highly accessible step location well outward of the vehicle side. An electrical control system electronically limits motor operation to avoid motor burnout in the case of step obstruction.

Abstract: A delayed turn-on and turn-off control circuit for an electric motor includes a motor relay having an electrical actuator and a normally open motor contactor which is connected in series between the motor and an electrical power source for running the motor when the electrical actuator is energized. A normally non-conductive electrical switching device is serially connected between the electrical actuator and the power source. A turn-on delay circuit is responsive to closing of a normally open motor start switch and produces an electrical signal to render the electrical switching device conductive only after a predetermined lapse of time following the closing of the motor start switch, thereby energizing the motor.