Abstract: An elevator safety system includes: at least two sensors, each of the sensors being configured for monitoring at least a portion of a hoistway of an elevator system and providing monitoring signals; a transformation unit which is configured for transforming the monitoring signals provided by at least one of the sensors and producing transformed signals corresponding to a common direction of vision; a comparison unit which is configured for comparing the at least two transformed signals and for generating a failure signal if a difference between the at least two transformed signals exceeds a predetermined threshold; and a detection unit, which is configured for detecting a person or undesired item in at least one of the two transformed signals and for generating an alarm signal if a person or undesired item is detected.

Abstract: A motor control system for controlling operation of a motor having a plurality of windings includes a gate driver to provide a control signal to one or more switching elements controlling a voltage applied to the plurality of windings and a Field Oriented Control (FOC) controller configured to generate a PWM signal for coupling to the gate driver, wherein the FOC controller comprises a d-axis control loop configured to generate an applied d-axis voltage and a q-axis control loop configured to generate an applied q-axis voltage. A stall detector is configured to calculate an estimate of the q-axis voltage and compare the applied q-axis voltage to a threshold based on the estimate in order to detect a stall condition of the motor.

Abstract: A control method used in a control unit of a power converter, connected by three output phases to a synchronous electric motor, the method being used for starting the motor and including a first step for determining the voltages to be applied to the output phases depending on a reference current, a second step for determining a frequency to be applied to the stator depending on a stator frequency, a step for application of the first step and the second step for a given duration, so as to allow the rotor of the synchronous electric motor to rotate at the stator frequency applied. The method is particularly effective for an architecture including a transformer and a sinus filter between the power converter and the electric motor.

Abstract: Apparatus for transmitting energy comprising an electrical machine arranged to convert between electrical and mechanical energy, and comprising a rotor (20) and control means (42, 44, 90) arranged to regulate the motion of the rotor to ensure that the power angle of the electrical machine is maintained within a range of a predetermined power angle. A signal generator (2, 6), such as a synchronous machine and associated flywheel, may generate a reference signal relating to the predetermined power angle and be powered by a frequency regulated electrical supply. The control means (42, 44, 90) may be a mechanical control linkage or servo control system and may regulate the output of the motion of the rotor in response to a change in its motion which the control means or a dedicated detection device detects. The electrical machine may be an electric motor, an electricity generator, or a machine switchable between motor and generator modes.

Abstract: A position limiting device includes a magnetic element, a detecting element, a motor, and a controller. The magnetic element is disposed in the center of the position limiting device, the motor is coupled to the detecting element, and the controller is electrically coupled to the detecting element and the motor. The detecting element is configured to detect magnetic fields generated by the magnetic element, and correspondingly generate and transmit a magnetic field intensity signal. The controller is configured to receive and process the magnetic field intensity signal to obtain a magnetic field intensity value. In addition, the controller is further configured to compare the magnetic field intensity value and a magnetic field intensity boundary value. When the magnetic field intensity value is less than the magnetic field intensity boundary value, the controller drives the motor so that the motor makes the detecting element to move correspondingly to the magnetic element.

Abstract: This invention relates to methods and devices for motor speed control. The invention has particular application in the control of motors over packet networks. In embodiments of the invention, phase-locked loop principles are used to remotely control the speed of an electric motor over a packet network. The setpoint for the motor is supplied by arriving timestamps from a speed-mapped variable frequency source. The shaft speed of the motor is measured with a tachometer with its output proportional to the motor speed. Any deviation of the actual speed from the setpoint is amplified by the power amplifier whose output drives the motor. Speed control over packet networks allow smoother operation of a process, acceleration control, different operating speeds for each process recipe, compensation for changing process variables, slow operation for setup purposes, adjustments to the rate of production, accurate positioning, and control torque or tension of a system.

Abstract: A ventilating system that can make an air flow rate variable includes a DC motor that drives blades and a control circuit that controls the DC motor. The control circuit includes a first current detecting unit that detects a current flowing in the DC motor, a rotating speed detecting unit that detects a rotating speed of the DC motor, and a control unit that controls the DC motor based on a rotating speed detected by the rotating speed detecting unit and a current detected by the first current detecting unit. The current detecting unit includes a plurality of low-resistance resistors, detects a motor current by using divided voltages of the low-resistance resistors, and calculates a ventilation air flow rate based on the rotating speed detected by the rotating speed detecting unit and the current detected by the first current detecting unit.

Abstract: A motor driving circuit for driving a motor, includes: a detecting circuit configured to detect a detection signal indicative of a current state of the motor; a command value generating unit configured to generate a command value indicative of a target state of the motor; an error amplifier configured to generate an error signal by amplifying an error between the detection signal and the command value; a pulse width modulator configured to generate a pulse signal; and an output circuit. The command value generating unit is configured to provide a variation to the command value.

Abstract: A rotary breaker that interrupts a transmission of a driving force from a motor to a drive mechanism unit is provided between the motor having a permanent magnet incorporated therein and the drive mechanism unit of an electric vehicle. A second controller controls the rotary breaker based on operation states of a power converting unit that has a power converter that drives the motor by converting a direct-current voltage or an alternate-current voltage into an alternate-current voltage with an arbitrary frequency and a first controller that controls the power converter, operation states of the motor and the rotary breaker, and an operation state of the second controller itself.

Abstract: An electromagnetic motor having a frame, and at least one disc rotatably mounted to the frame. At least one permanent magnet is mounted on the disc, and at least one electromagnet is mounted to the frame in magnetic proximity to the at least one permanent magnet. A battery is electrically coupled to the motor for powering the at least one electromagnet. A switch controls electrical power between the battery and the at least one electromagnet, and a sensing means is provided for controlling the switch to activate the at least one electromagnet with respect to the at least one permanent magnet to cause the at least one disc to rotate. Preferably, a generator is mechanically coupled to the motor and electrically coupled to the battery for generating electrical power to the battery, and a renewable energy source such as a photovoltaic cell is electrically coupled to the motor to supplement any net electrical loss.

Abstract: A ventilating system that can make an air flow rate variable includes a DC motor that drives blades and a control circuit that controls the DC motor. The control circuit includes a first current detecting unit that detects a current flowing in the DC motor, a rotating speed detecting unit that detects a rotating speed of the DC motor, and a control unit that controls the DC motor based on a rotating speed detected by the rotating speed detecting unit and a current detected by the first current detecting unit. The current detecting unit includes a plurality of low-resistance resistors, detects a motor current by using divided voltages of the low-resistance resistors, and calculates a ventilation air flow rate based on the rotating speed detected by the rotating speed detecting unit and the current detected by the first current detecting unit.

Abstract: The invention relates to an independent drive device for an aircraft, the drive device comprising a motor member, drive means for driving an aircraft wheel in rotation, which means are adapted to co-operate with said wheel to drive it in rotation, and coupling means interposed between the motor member and the drive means to selectively couple the wheel to the motor member, the coupling means comprising two coupling members of complementary shape, comprising a first coupling member constrained to rotate with the drive means and a second coupling member constrained to rotate with the motor member. The independent drive device includes measurement means for generating information representative of a relative speed of rotation of the second coupling member relative to the first coupling member, the device being associated with motor control means adapted to cause the motor to rotate so as to cancel the relative speed of rotation between the coupling members prior to coupling them together.

Abstract: The invention relates to a piece of furniture and to a device for controlling the movement of furniture parts which can be moved with respect to one another, having a drive unit by means of which a first furniture part can be moved relative to a second furniture part, in a driven manner, via a monitoring unit for monitoring the movement of said first furniture part. According to the invention, the monitoring unit is designed such that, after an initiating action by the monitoring unit, the first furniture part is moved to a predetermined position and is stopped there, with the predetermined position differing from a final position of the first furniture part.

Abstract: A method for configuration of a device for controlling the movement of a plurality of movable furniture parts which can be moved in a driven manner relative to a stationary furniture part by means of a drive unit and a monitoring unit for monitoring the movement of the movable furniture parts. In order to match the movement of the movable furniture parts, at least an inner furniture part is associated with an outer furniture part such that, when a configuration mode is activated, the association of the at least one inner furniture part with the outer furniture part is created by a sequence of opening and/or closing movements of the movable furniture parts that are associated with one another.

Abstract: A method for adjusting a closing gap in a piece of furniture, which comprises a device for moving a movable furniture part relative to a stationary furniture part by means of a drive unit, by means of which the furniture part can be driven to move relative to the stationary furniture part via a monitoring unit for monitoring the movement of the movable furniture part, with the closing gap being formed between a front part of the movable furniture part and the stationary furniture part when the movable furniture part is in a closed position with respect to the stationary furniture part. According to the invention, the closing gap is adjusted in an activated, electronically assisted, adjusting mode.

Abstract: A motor control device includes a sensing circuit, a phase-shifting circuit, a comparing circuit and a control circuit. The sensing circuit senses the motor to generate a sensing signal. The phase-shifting circuit is electrically connected to the sensing circuit and receives the sensing signal to generate a phase-shifting signal. The comparing circuit is electrically connected to the phase-shifting circuit and receives the phase-shifting signal to generate a comparing signal. The control circuit is electrically connected with the comparing circuit and the motor, and receives the comparing signal to generate a control signal so as to control the rotation speed of the motor.

Abstract: A system and method for limiting input voltage to a power delivery system having regeneration capability. According to various embodiments, the system includes a regulator having a multiple input variables and at least one output variable; and an accumulator in communication with the regulator wherein the accumulator presets the output of the regulator to facilitate a quick output as well as accumulates error values related to the multiple input variables and facilitates a change by the regulator to the at least one output variable based upon the accumulated values.

Abstract: The invention relates to a method and an appliance for monitoring the safety of a transport system (1). The transport system comprises a transport appliance (2) and also a synchronous motor (3) for moving the transport appliance. In the method the motion information of the transport appliance is determined with two channels, and if the determined motion informations deviate from each other by more than the set limit value, an emergency stop is executed.

Abstract: Certain exemplary embodiments comprise a method that can comprise, via a device that originates sub-harmonic vibrations, applying a vibration treatment, to a rotor of an electric motor for a predetermined time period. The rotor can be thermally sensitive. The vibration treatment can be adapted to reduce internal stresses in the rotor, thereby reducing a vibration level of the rotor.

Abstract: A controlling device includes a range switch mechanism, range switch operating means, operation frequency monitoring means, and heat generation limit controlling means. The range switch mechanism is adapted to change a shift range using a motor. Through the range switch operating means, an occupant inputs a required shift range. The motor is controlled in accordance with the required shift range such that the shift range is changed into the required shift range. The operation frequency monitoring means monitors an operation frequency of the range switch operating means. The heat generation limit controlling means switches a control of the motor to a heat generation limit control when the operation frequency of the range switch operating means exceeds a predetermined frequency.

Abstract: Systems and methods of controlling a permanent magnet motor without a mechanical position sensor are provided. In accordance with one embodiment, a motor control system includes an inverter configured to receive direct current (DC) power and output a power waveform to a permanent magnet motor, driver circuitry configured to receive control signals and drive the inverter based upon the control signals, a current sensor configured to determine a sampled current value associated with the power waveform, and control circuitry configured to generate the control signals based at least in part upon a comparison of a flux-producing component of the sampled current value and a flux-producing component of a command reference current value.

Abstract: A backward pedaling detection circuit has a charging/discharging circuit for charging and discharging the external capacitor to meet the threshold voltage required by the hysteresis comparator, based on the input from the hall sensor. An internal pull-down circuit, based on the pedal speed, keeps the circuit from false triggering. A comparator with hysteresis (Schmitt trigger) sets the upper and lower threshold voltage and eliminates the effect of noise. AND gates act like switches to allow the selected signal to pass through.

Abstract: A motor control device includes a sensing circuit, a phase-shifting circuit, a comparing circuit and a control circuit. The sensing circuit senses the motor to generate a sensing signal. The phase-shifting circuit is electrically connected to the sensing circuit and receives the sensing signal to generate a phase-shifting signal. The comparing circuit is electrically connected to the phase-shifting circuit and receives the phase-shifting signal to generate a comparing signal. The control circuit is electrically connected with the comparing circuit and the motor, and receives the comparing signal to generate a control signal so as to control the rotation speed of the motor.

Abstract: In an impulse wrench there is provided an impulse unit with a motor driven inertia drive member, and a movement detecting device arranged to detect an angular movement of the inertia drive member. The movement detecting device includes a rotating disc rigidly connected to and co-rotating with the inertia drive member. The impulse wrench also includes a sensing device including four Hall-element type sensors, and the disc has a rim portion which is magnetised to provide a number of magnetic poles for activating the sensors at rotation of the inertia drive member. The sensors are arranged in pairs such that the delivered signals from the sensors in each pair has a relative phase lag of 180 degrees, and the sensors of one of the pairs are arranged to deliver signals with a phase lag of 90 degrees relative to the sensor signals from the other pair.

Abstract: A system and method for sensing capacitance at the edge of a movable barrier and for detecting an obstruction includes positioning a conductive member within or about a holder. A sensed capacitance between the conductive member and ground. A controller is coupled to the sensor. The controller determines whether an obstruction exists within a path of the barrier by analyzing the sensed capacitance. The conductive member and holder move away from a physical reference as the physical reference is approached such that the sensed capacitance between the conductive member and the physical reference remains below a predetermined threshold.

Abstract: The invention relates to an electromotive adjustment drive which is operated by a safety voltage, for instance, an adjustment drive for the adjustable components of pieces of furniture. The adjustment drive is equipped with a hand-operated device and a control unit which is operated with the device and connected by at least one cable to a voltage source to which the mains voltage can be supplied. The adjustment drive is so configured as to allow an electrical separation between the voltage source and the transformer, when the adjustment drive is not in operation, without requiring special cables. Furthermore, the adjustment drive should be configured in such a way that the item equipped with the adjustment drive does not contain any cables or lines to which mains voltage is supplied. According to the invention, there is provided a power supply module (12) which is spatially separated from the control unit (14) and arranged between the control unit (14) of the adjustment drive (11) and the voltage source.

Abstract: The increasing use of electrically powered vehicles has created a need for inexpensively and effectively measuring high currents for motor control, as for example digital motor control. Because the high operating voltages of traction motors, the motor current sensors should be non-contacting. A non-contacting current sensor having a rated capacity significantly less than the motor winding current is coupled to one or more of the conductors of a paralleled multiconductor motor winding for sensing the current in that conductor. The paralleled electrical motor conductors are paralleled by additional similar conductors, so that only a fraction of the current to be measured flows through the conductor(s) associated with the sensor. The current sensor elements may be mounted on a pc board, which supports the elements, and also has one or more printed patterns which define conductors associated with the sensor.

Abstract: An induction actuated container includes a container body, a container cover, a drive and an induction element. The drive includes a driven operating member and a driving member. The induction elements includes a sensor and an actuating controller for the driving member. One end of the driven operating member is transmissively connected with the container cover, the other end is transmissively connected with the driving member, and the sensor is electrically connected with the actuating controller for the driving member, and the actuating controller for the driving member is connected with a controlling end of the driving member. A signal caused by the approaching of a human or object is received by the sensor and is converted into an electrical signal. Then, the actuating controller for the driving member controls the driving member to perform a corresponding mechanical action.

Abstract: A method and system for calibrating a motor-driven instrument pointer (8) against a stop (5) without using feedback includes, in a first power state, driving the pointer (8) at full torque against the stop (5), then driving the pointer (8) against the stop at a reduced torque for a predetermined radial distance so at the pointer (8) is caused to be held against the stop (5). A third driving step, at reduced torque for a further predetermined radial distance, may be used in a second power state to move the pointer (8) against the stop (5).

Abstract: A movable barrier operator includes a wall control switch module having a learn switch thereon. The switch module is connectable to a control unit positioned in a head of a garage movable barrier operator. The head unit also contains an electric motor which is connected to a transmission for opening and closing a movable barrier such as a garage door. The switch module includes a plurality of switches coupled to capacitors which, when closed, have varying charge and discharge times to enable which switch has been closed. The control unit includes an automatic force incrementing system for adjusting the maximal opening and closing force to be placed upon the movable barrier during a learn operation. Likewise, end of travel limits can also be set during a learn operation upon installation of the unit.

Abstract: An object detection system includes a sensor in communication with a controller which identifies contact with the sensor. In a preferred embodiment the sensor is a piezo film which generates a signal when an object applies a predetermined force to the edge of the moveable glass member. This signal is identifiable by the controller in communication with the piezo film. Another embodiment of the sensor provides a pair of substantially parallel segments of conductive material applied along the edge of the window. When an object is in contact with both segments of conductive material an electrical signal is conducted and identified by the controller. When the controller determines an object is in contact with the sensor and therefore the moveable glass member, the controller halts or reverses the movement of the moveable glass member to prevent trapping the object between the closing moveable glass member and the frame.

Abstract: An operator for opening and closing movable barriers such as garage doors comprising a pass-point limit system which is a component of an operating head. An operator for a rolling shutter or gate can be installed on either side of the opening. A dual pass-point system provides a unique pass-point regardless of direction of mounting the operator, regardless of the direction of travel for opening the barrier, and regardless of installation configuration, eliminating the need for the installer to know which direction the motor is rotating or the barrier is travelling.

Abstract: An apparatus invention relates to an apparatus and method for monitoring an interior space which is closed off by a locked and/or manually non-unlockable door, flap, sliding sunroof or the like, for example a passenger compartment or luggage compartment of a motor vehicle, with respect to living entities enclosed therein and the quality of their living environment, having a control circuit and sensor evaluation arrangements connected thereto, which arrangements each interact with at least one sensor, a first sensor evaluation arrangement outputting a first signal to the control circuit if there are living entities in the interior space, and a second sensor evaluation arrangement outputting a second signal to the control circuit if the living environment changes in the direction of life- and/or health-threatening states, at least one actuator connected to the control circuit acting on a motor-actuatable closure of the door, flap, sliding sunroof or the like, which is activated by the control circuit for the pu

Abstract: The present invention discloses a novel method and apparatus for determining the position of a window glass in an aperture window as between one of two or more regions. Further, the present invention discloses a method and apparatus for determining the direction of travel of a window. The present invention senses the position and direction of travel of a window by measuring the amount of current in a motor that is suitable for moving the window as the window passes one or more elastic objects.

Abstract: The present invention relates to a trapping protector capable of detecting the presence of an object in a sensing region when connected with a device for creating input signals and evaluating output signals. Said trapping protector comprises a body portion, at least one ground electrode, at least one sensor electrode arranged spaced apart from said ground electrode and embedded in said body portion, and a zone of reduced rigidity between said at least one ground electrode and said at least one sensor electrode. Said zone reduces the force required for triggering said trapping protector.

Abstract: An apparatus and a method for operating a rain sensor (10) that outputs a sensor signal (18, 22) as a function of the wetting of a window (11) are proposed, having a controller (16) which as a function of the sensor signal (18, 22) outputs a control signal (28) to the rain sensor (10) for regulating the sensor signal (18, 22); for signal evaluation, the sensor signal (18, 22) and in addition the control signal (28) are used for tripping switching events of a device.

Abstract: The present powered sliding device comprises a wire drum, a motor for rotating the drum, and a clutch means provided between the drum and the motor. The clutch means has a coupled state for rotating the drum, an uncoupled state, and a brake state. The clutch means is displaced from the coupled state to the brake state when the wire drum is rotated at an over speed. The clutch means in the brake state transmits the over speed rotation of the wire drum to the motor.

Abstract: The invention relates to a circuit for controlling an electrically activated motor vehicle door lock or the like, with a lock latch (1) and a detent pawl (2) which keeps the lock latch (1) in the closed position and with an electric motorized auxiliary closing drive (4) which is turned on after the lock latch (1) has reached a preclosing position and then moves the lock latch (1) by motor into the main closing position, there being a switch (16) which recognizes the preclosing position, especially a lock latch switch which scans the position of the lock latch (1).

Abstract: A motor driver has a braking control circuit. The braking control circuit shuts off the supply of an electric current to the coils included in the motor when a motor control signal shifts to a predetermined level and, after a predetermined length of time secured in accordance with an index signal, starts application of braking to the rotation of the motor by the use of a braking circuit. The index signal is obtained from the signal that indicates the rotational position of the motor. The motor control signal is fed from a control signal generating circuit to the braking control circuit.

Abstract: An operator for opening and closing movable barriers such as garage doors comprising a pass-point limit system which is a component of an operating head. An operator for a rolling shutter or gate can be installed on either side of the opening. A dual pass-point system provides a unique pass-point regardless of direction of mounting the operator, regardless of the direction of travel for opening the barrier, and regardless of installation configuration, eliminating the need for the installer to know which direction the motor is rotating or the barrier is travelling. The operator automatically learns both the open and close limits, regardless of direction of travel and without having to press a learn switch to set the open and close limits.

Abstract: A stator 3 of a motor 1 is pivotally supported on a stationary system 5 by an elastic member 28, 11a, 42 provided along the circumferential direction of the stator 3, and a detector 11 for detecting a rotational force of the stator 3 is provided to execute the control of stopping, accelerating, decelerating or reversing the operation of the motor 1 based on a detection signal from the detector 11. When the motor load is increased, transmission of torque from the action system 3 to the reaction system 4 of the motor 1 is cut off, and consequently the stator 3 itself of the motor 1 pivots with respect to the stationary system 5 as a reaction. In this stage, the detector 11 detects the rotational force of the stator 3 to stop, accelerate, decelerate, or reverse the operation of the motor 1.

Abstract: A object sensor system for a swing door includes swing-side and approach-side sensors. Each of the sensors includes light-emitters and light-receivers which are mounted on a swing door. The light-emitters emit light toward a floor, and the light-receivers receive the light as reflected from the floor. The light emitted and received provides an object sensing zone which has a rectangular shape on the floor having a width equal to or larger than the width of the door. The sensing zone includes a main sensing area closer to the door and an auxiliary sensing area extending along the main sensing area. The auxiliary sensing area is disabled when the door moves.

Abstract: A control system for an electric vehicle includes an accelerator opening detecting device for detecting a position of an accelerator, and an output command value calculating device connected to the accelerator opening detecting device for calculating an output command value of a drive motor of the electric vehicle based upon the detected accelerator opening. A motor control device is connected to the output command value calculating device, and controls the output of the motor based upon the output command value. An accelerator opening learning device learns actual accelerator opening positions, and includes at least one of a full-closure learning apparatus for generating a full-closure determined value of the accelerator based upon an output of the accelerator opening detecting device, and a full-open learning apparatus for generating a full-open determined value based upon the detected accelerator opening.

Abstract: A rotation detecting means detects rotation of a mechanical movable portion and outputs a detection signal corresponding to the rotation rate of the mechanical movable portion. A rotation monitoring circuit, to which the detection signal from the rotation detecting means is provided, outputs a rotation-existing signal when the detection signal indicates that the mechanical movable portion is rotating. A rotation stop monitoring circuit, to which the detection signal from the rotation detecting means is provided, outputs a rotation-stop signal when the detection signal indicates a rotation rate lower than a predetermined rotation rate, and a movable portion control circuit uses at least either the rotation-existing signal or the rotation-stop signal and an external command signal for input signals to control the mechanical movable portion with logic of these signals.

Abstract: The present invention relates to a safety ensuring apparatus for ensuring the safety of an operator.A mechanical moving part is surrounded by a safety enclosure with a door of the safety enclosure provided with a door lock device constructed such that the door lock device releases a door lock when a current is supplied from outside to excite a solenoid incorporated therein. The apparatus is constructed such that a lock is released when the mechanical moving part is stopped. Moreover, the construction incorporates a moving part monitoring sensor which monitors if the mechanical moving part is stopped. When mechanical moving part is stopped, the moving part monitoring sensor generates, without a negative operation, an output signal of logic value 1 corresponding to a high energy condition, and the solenoid of the door lock device is excited by this output signal.As a result, the lock of the door lock device is released once the mechanical moving part has stopped.

Abstract: A safety device for a tool powered by an electric motor. It has a main switch, electronic controls, and a tachometer-generator. In order to provide a device for switching off a motor as a function of motor speed that is simple and economical and that will retain the same nominal switch-off value for the total life of the device, a relay is wired in parallel with the motor and controls the supply of power to the motor through a relay contact.

Abstract: An assembly for driving a thermocouple into a thermocouple well includes two pinch wheels biased to grip the thermocouple probe between them. The pinch wheels are located adjacent to the thermocouple well. A reel of supporting cable is positioned remote from the well. A free end of the cable on the reel is connected to the thermocouple probe so that as the probe is driven into and out of the well, the cable is unwound and wound onto the reel.

Abstract: An object sensing apparatus includes a plurality of light emitting diodes for illuminating a region of space and a plurality of closely arranged light detectors for receiving light reflected from an object. The apparatus is particularly useful in connection with automatically operated doors.

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.