Abstract: Apparatus for developing a series of square-wave pulses from an alternating voltage that is generated in the pick-up coil of a variable reluctance sensor that is associated with a slotted wheel that is driven by the crankshaft of an internal combustion engine. The system has an adaptive control which comprises a peak detector, a capacitor and a voltage comparator. The capacitor is charged to a peak voltage that corresponds to the peak value fo the positive half-cycles of the alternating voltage. The comparator is connected to compare the peak voltage and a voltage that corresponds to the magnitude of the positive half-cycles. A diode is connected between the pick-up coil and the peak detector which prevents charging of the capacitor and accordingly prevents adaptive control until the voltage induced in the pick-up coil is high enough to cause the diode to conduct in the forward direction.

Abstract: A bearing apparatus is provided for a driven shaft of an automobile. It includes a rotational speed detector for detecting a rotational speed of a wheel of the automobile by detecting the rotational speed of a circular detected member which has a plurality of projections provided at even intervals in the circumferential direction. The detected member is fixed to one end of a driven shaft. The other end of the driven shaft includes a flange for mounting of a wheel. The shaft is part of an inside member which is rotatably supported by an outside member fixed to a chassis through a plurality of rolling elements. Detected speed is sent to an antilock brake system through a connector.

Abstract: A rolling bearing arrangement for an anti-locking brake system has a pulse ring with projections directed toward the fixed ring. The surfaces of the projections that activate the pulse generator are cut during the hard working of the bearing ring. The pulse generator is integrated in the rolling bearing arrangement. Thereby, on one hand, tolerance limited operational differences in the amplitude and shape of the pulses are avoided, especially during slow rotational speeds of the bearing ring. Furthermore, external influences on the pulse generator and pulse ring caused by rough roads do not occur due to the hermetic encapsulation of the sensitive components.

Abstract: An antifriction bearing assembly comprises a stationary outer race and a rotatable inner race with two annular rows of rolling elements between the races. A sensor assembly is mounted in the outer race so as to position a sensor between the races and the two rows of rolling elements, and an encoder is mounted on the inner race between the rows of rolling elements. Several sensor assembly and encoder configurations are included.

Abstract: A magnetic-field-sensitive device includes several magnetic-field sensors. Each sensor comprises a compound element surrounded by a coil winding. Each compound element is made of two ferromagnetic cell components extending in one axial direction with uniaxial magnetic anisotropy and with different coercive field strengths. A spontaneous reversal of magnetization is produced by an external magnetic switching field only in the cell component having the lower coercive field strength. The magnetic-field sensors are combined to form a series arrangement, or array, and the coil windings and cell components of the magnetic-field sensors of the array are formed as thin-film structures on a non-magnetic substrate.

Abstract: A probe transducer subassembly for a rotational speed sensor assembly is provided. A probe body (1) has a transducer portion (14) extending through an opening (19) into the interior of housing for electromagnetic cooperation with an exciter rotor, a distal portion (15) carrying connection devices extending therefrom and an enlarged diameter intermediate portion defining inwardly and outwardly facing shoulders. The shoulders cooperate with the exterior surface of the housing surrounding the opening and a shoulder in a shroud member (2) to axially position the probe in the housing and allow the probe to be clamped between the housing and the shroud.

Abstract: A tachometer particularly adapted for operation as a rotational velocity feedback transducer is provided. First and second proximity detectors are used to monitor orthogonal positions of an irregular surface portion of a rotating shaft and provide x and y signals that are substantially in quadrature. The x and y signals are differentiated with respect to time to provide differential signals that are representative of dx/dt and dy/dt, respectively. Signals representative of products x dy/dt and y dx/dt are generated from the x signal and the differential signal dy/dt, and the y signal and the differential signal dx/dt, respectively. A signal representative of algebraic sum x dy/dt--y dx/dt is generated from the signals representative of products x dy/dt and y dx/dt. A signal representative of quotient of (x dy/dt-y dx/dt) divided by the displacement r.sup.

Abstract: The invention makes it possible to detect and measure the movement of a moving member (50) through an amagnetic or low permeability metal wall. The installation requires ferromagnetic material targets placed at regular intervals over the moving member. The transducer is positioned facing the moving member by its detection face (16). It comprises two ferromagnetic cores (2, 8) surrounded both by an exciting coil (4) and a measuring coil (10), at whose terminals the measuring signal is taken. The latter is proportional to the variable reluctance of the magnetic circuit, which varies as a function of the position of the ferromagnetic targets (48). The transducer is completed by a balancing core (34). Application to the measurement of the displacement of control rods in the vessel of a pressurized water reactor.

Abstract: An antifriction bearing assembly has rolling elements and a magnetic encoder ring housed in an outer ring with two portions which can have different diameters. A sensor is removably attached to the outer ring in alignment with the encoder ring. Various seal assembly configurations may be used to seal the bearing while accommodating the sensor.

Abstract: A circuit for determining the speed of rotation of a wheel, has an inductive transmitter (1), the output of which is connected to a pulse-shaping device (7) whose output is connected to an evaluation device. The inductive transmitter is connected to an evaluation circuit (11) by means of a cable (6). The evaluation circuit is intended, on the one hand, to make certain that the input signal of the inductive transmitter (1) can be evaluated while, on the other hand, it should be able to detect errors which may occur, for instance due to a break in the cable (6) despite the presence of dirt resistances (R.sub.S). For this purpose, an auxiliary circuit (10) is provided which varies the internal resistance of the pulse-shaping device (7) as a function of the speed.

Abstract: A double row tapered roller bearing, which has the capacity to produce a pulsating electrical signal, the frequency of which reflects angular velocity, includes an outer race having a pair of tapered raceways that are presented inwardly, two cones, each having a tapered raceway that is presented outwardly toward a different raceway of the outer race, and tapered rollers arranged in two rows between the raceways of the outer race and the cones, with the small ends of the tapered rollers in each row being presented toward space between the two rows. The outer race has an oblique bore which opens into the space, whereas one of the cones has an axially directed seat which extends into the space. The oblique bore contains a sensor while the axially directed seat has a target wheel fitted over it, and the target wheel has an oblique operative surface that is presented opposite the inner end of the sensor, there being a slight gap between the two.

Abstract: In a measurement device for contactless determination of the rotation angle and/or rotation speed, a disk is fastened on a shaft so as to be fixed with respect to rotation relative to it. During the measurement process, layers of material with good electrical conductivity which are arranged on one or both opposing sides of the disk are moved relative to receiver coils located on opposite sides of the disk (16a and 16b). The measurement device can work according to the eddy current measurement method, as well as according to the inductive method. In order to compensate for measurement errors, the conductive layers are arranged at approximately equal distances (a, b) between two coils. In addition, the greatest possible quantity of measurement points can be used for forming an average.

Abstract: An antifriction bearing assembly has rolling elements and a magnetic encoder ring housed in an outer ring with two portions which can have different diameters. A sensor is removably attached to the outer ring in alignment with the encoder ring. Various seal assembly configurations may be used to seal the bearing while accommodating the sensor.

Abstract: DC motors without collectors require position sensors, which recognize or identify the angular position of the rotor, in order to supply a pulse for control of the current in the coil at a suitable point in time. Hall probes which, as a rule, are used as positional sensors, involve a series of disadvantages, such as for instance sensitivity to temperature and radiation. In order to avoid these disadvantages, coils with a magnetic core through which alternating current is passed are installed in the stator-rotor air gap in accordance with the invention. The rotor comprises in the axial segment opposite the coils a magnetic portion and a nonmagnetic portion. This generates a change in the voltage drop at the coil during each rotor revolution.

Abstract: A wheel speed sensor apparatus for detecting the rotational speed of a road wheel of an automotive vehicle. The apparatus includes a toothed rotor rotatable with a road wheel of the vehicle. A sensor main body contains an element which produces an electical signal in response to adjacent passage of the rotor teeth upon rotation of the sensor rotor. The sensor main body is fitted inside inside a metallic sleeve in a manner such that a tip end section of the sensor main body is in close proximity to the sensor rotor. The metallic sleeve is fitted in the installation hole. The installation member is made of aluminum or aluminum alloy and is connected with the base section of a suspension strut of the vehicle.

Abstract: A sensor assembly for installation between an axle shaft and axle tube includes a roller bearing held coaxially to a sensor ring by a clutch member that is released when the shaft is turned after installation.

Abstract: A tachometer particularly adapted for operation as a rotational velocity feedback transducer is provided. First and second proximity detectors are used to monitor orthogonal positions of an irregular surface portion of a rotating shaft and provide x and y signals that are substantially in quadrature. The x and y signals are differentiated with respect to time to provide differential signals that are representative of dx/dt and dy/dt, respectively. Signals representative of products x dy/dt and y dx/dt are generated from the x signal and the differential signal dy/dt, and the y signal and the differential signal dx/dt, respectively. A signal representative of algebraic sum x dy/dt-y dx/dt is generated from the signals representative of products x dy/dt and y dx/dt. A signal representative of quotient of (x dy/dt-y dx/dt) divided by the square of the displacement r.sup.

Abstract: An apparatus for tranmitting signals that can be broken down into at least one AC voltage component between a rotor and a stator from a sender unit to a receiver unit, with the help of annular coils, the coil windings of which form components of the sender or receiver unit, and which are arranged coaxially to the axis of rotation of the rotor and inductively coupled is to be developed so as to generate measured values that are associated with the rotational speed.

Abstract: A position encoder for monitoring the position of a robot arm includes an incremental encoder section which can be initialized locally by an initialization section. The initialization section comprises three engaged encoder gears with relative prime number of teeth, e.g., 23, 24 and 25, so that respective index apertures of the gears precess with successive revolutions of the gears. Upon startup, the robot arm can be moved sufficiently for all three apertures to be detected so that their relative phase positions can be determined. The relative phases can be used to determine an absolute initialization position. Once this initialization position is determined, robot motions can be tracked using the incremental encoder section.

Abstract: A pulse shaper for inductive pickups, in particular for inductive speed pickups or angle of rotation pickups on internal-combustion engines, is proposed, which has a voltage controlled voltage divider (14, 17, 19) at its input. A level adaptation takes place of the signal delivered by the inductive pickup (10) to a Schmitt trigger stage (44), at the output (57) of which a voltage jump occurs whenever the signal delivered by the pickup (10) rises above a certain value and falls below a certain value. The voltage divider at the input of the pulse shaper is formed by a resistor (14) and a first and second diode (17, 19), the differential resistance of which can be set by controlled voltage sources (24, 28). The special advantage of the circuit is that no higher voltage than the operating voltage of the pulse shaper can occur after the resistor 14 at the input. The pulse shaper is ideally suited for integration, as only easily integratable components are contained in the circuit.

Abstract: A miniature motor with a frequency generator comprising a motor portion having a stator with a permanent magnet for forming a magnetic field and a rotor with rotor windings wound on a rotor core; electric current being fed to the rotor windings via a commutator making sliding contact with brushes, and a frequency generator for detecting the revolution of the motor, in which the frequency generator comprises a frequency generator rotor, mounted on the motor rotor, having a disc-like rotor portion made of a soft magnetic material and equipped with a plurality of magnetic-pole teeth on the outer periphery thereof, an internal-gear core of an annular disc shape, made of a soft magnetic material, disposed in such a manner as to come in contact with the inside of a motor housing and face the outer circumferential surface of the rotor portion and equipped with a plurality of magnetic-pole teeth on the inner periphery thereof, a permanent magnet forming a magnetic field between the magnetic-pole teeth of the rotor po

Abstract: A circuit for processing a high frequency output signal from a variable reluctance transducer, this signal including an unwanted low frequency component, comprises a comparator having a first input receiving the transducer signal and a second input receiving the same transducer signal but via a low pass filter. The comparator therefore provides an output representing the high frequency variations in the transducer signal and substantially unaffected by the low frequency component. Alternatively, the transducer signal may be applied to a circuit providing a first output signal varying as the low frequency component and also providing a second output signal varying as the high frequency variations in the received transducer signal, the first output signal being used as a feedback control which tends to render the second output signal free of low frequency variations.

Abstract: A sensor ring and seal casing for a wheel speed sensor are maintained as a unit handled package by a specially designed shipping and installation jig, which protects the components before they are installed, and which maintains the components in the proper orientation to be installed.

Abstract: An improved sensor assembly for providing an electrical signal representative of the velocity of a movable body. The assembly includes a sensor for sensing the velocity of the body and providing the signal and a mounting block disposed close to the body for locating the sensor in a predetermined position with respect to the body. The mounting block has a passageway extending through the block for receiving the sensor and for restricting the movement of the sensor along a direction co-existent with respect to the longitudinal axis of the sensor. The sensor itself includes an elongated barrel portion having a sensing tip in one end. The elongated barrel portion includes a shoulder stop located along the elongated barrel portion at a predetermined position from the end of the elongated barrel portion having the sensing tip.

Abstract: A sensor includes a housing which is narrow at least at its front portion. An insertion portion of a holder is inserted in the front portion of the housing. A plurality of elongate conductors are printed on an outer surface of the insertion portion of the holder, the conductors extending generally in the direction of the axis of the housing. A sensing element is mounted within the front portion of the housing and is disposed forwardly of the holder. The sensing element has terminals extending therefrom toward the holder in generally parallel relation to the printed conductors. The terminals are soldered respectively to the printed conductors, thereby retaining the sensing element on the holder.

Abstract: Assembly of a vehicle non-driving wheel hub equipped with a pulser and sensor unit for sensing the speed of the wheel and comprising an integral roller bearing (1, 2, 3) with two rows of rolling elements located between two internal roller bearing rings (2, 3) and an external ring (1) constituting the hub for securing the wheel, characterized by the fact that the stub axle (4) comprises at one of its end located towards the wheel (5) a shoulder flange (6) bearing on one (2) of the rings, and at its other end a threaded portion (8) making it possible, with the help of a stop nut (9), simultaneously to tighten the two internal rings (2, 3) against the stub axle carrier (7) and mount the stub axle (4) in the said stub axle carrier after the stub axle has been introduced into the stub axle carrier.

Abstract: A device for determining the rotary-angle position of rotary drives which can also determine the rotary speed. A magnet rotor generating a rotating magnetic field is provided for the purpose of determining the rotary speed with a cam disc suited for screening magnetic field lines, and to arrange coacting inductive transmitter and receiver heads on both sides of the cam disc, for determining the rotary-angle position. Due to the fact that the electromagnetic radiation emitted by the transmitter head is screened, the output signal of the receiver heads obtained is an envelope-modulated signal which can be evaluated for determining the position, for example by phase comparisons with additional envelope-modulated output signals of other receiver heads. The axial magnetization lines emanating simultaneously from the magnet rotor serve for inducing electric voltages in flat coils arranged axially before the magnet rotor, in overlapping annular shape.

Abstract: An antifriction bearing assembly comprises a stationary outer race and a rotatable inner race with two annular rows of rolling elements between the races. A sensor assembly is mounted in the outer race so as to position a sensor between the races and the two rows of rolling elements, and an encoder is mounted on the inner race between the rows of rolling elements. Several sensor assembly and encoder configurations are included.

Abstract: A speed detector, for use with a tone wheel having metal teeth, employs two coils positioned in offset relation near the tone wheel for interacting with the tone wheel teeth and thus changing their respective inductances. The coils preferably include iron cores to enhance magnetic coupling. One coil is in a phase sense oscillator circuit and the other is an a tuned sensor network. The oscillator is coupled to, and drives, the tuned network. The change in coil inductances effects a phase shift of the resulting signals in the oscillator and the tuned network, the magnitude of that phase shift typically being double that for a comparable single coil system. The output signals of the oscillator and tuned network provide inputs to a phase condition detector which looks for a reversal in their phase sequence and uses such event to provide timing reference pulses for a final determination of speed in a known manner.

Abstract: In an angular pulse generator having a movable generator part and a read head, the read head has a primary winding (W1) fed with an alternating voltage of a defined frequency and has a secondary winding (W2) whose induced secondary voltage is modulated by passing teeth and intervening gaps of the generator part. An evaluation unit evaluates the phase difference between the alternating voltage and the secondary voltage and forms a pulse for every passing tooth. A stray flux return line surrounds the primary winding (W1), so that the majority part of the primary flux linked to the primary winding (W1) flows via the stray flux return line for a large gap distance of the generator part.

Abstract: A pulser ring has cylindrical inner and outer rings nested together. The inner ring is formed at its one end with protrusions arranged at equal angular intervals. The outer ring is in the shape of a round comb and has its teeth engaged at a portion near the tip thereof in the grooves defined between the adjacent protrusions formed on the inner ring. The tip of each tooth protruding from the grooves is bent radially inwardly so as to engage the end face of the protrusion on the inner ring, thus coupling the inner ring and the outer ring together.

Abstract: A sensor is connectable with a load circuit via two conductors. The sensor receives its electrical power from the load circuit via the two conductors and similarly provides its output signal indicative of the sensed phenomenon via the same conductors. An unregulated source potential is provided to a terminal of the sensor from a supply potential via the load circuit. Voltage regulating circuitry in the sensor converts the unregulated source potential to a regulated operating potential for its active circuit elements. Certain output circuitry in the sensor is connected to the terminal having the unregulated source potential for conveying an output signal from the sensor to the load circuit.

Abstract: A vehicle wheel speed sensing system comprises a magnetic ring mounted on the wheel hub and a sensor mounted on the spindle. The magnetic ring is polarized at regular circumferential intervals so that as the hub rotates on the spindle, magnetic impulses are detected by the sensor which generates an electrical signal corresponding to the rotational speed of the hub. The radially inner surface of the magnetic ring is non-circular and fits onto a correspondingly non-circular radially outwardly facing surface of a groove in the hub. The groove also comprises an axially inwardly facing shoulder against which the magnetic ring is disposed. A sealing ring that seals the axially inner end of the hub to the spindle also has a portion that radially overlaps the magnetic ring for cooperating with the groove shoulder to axially capture the magnetic ring on the hub. In this way no separate attaching parts are required for mounting the magnetic ring on the hub.

Abstract: A position and speed detecting device is provided. This device includes a detection-signal generator comprising a rotor magnet assembly having a plurality of magnetic poles and a coil pattern for signal detection which moves relatively facing magnetized bodies of the rotor magnet assembly, a speed-signal detector for taking out a signal for frequency detection from said coil pattern for frequency-signal detection to produce a signal for speed detection; and a position-signal detector for producing a signal for position detection from said coil pattern for position-signal detection.

Abstract: An apparatus for detecting blade passing times includes a sensor for producing an input signal each time a blade passes the sensor. A zero crossing detector produces an output signal each time the input signal crosses a reference axis. A phase shifter shifts the phase of the input signal to produce a gating signal coinciding with the expected arrival time of the blade at the sensor. A gating device is responsive to the gating signal for conducting output signals which occur during the expected arrival time of the blade at the sensor.

Abstract: A cycle time of pulses converted from an electrical signal generated at a rotational sensor is counted. In determining a cycle of the pulses, either a rising edge or a falling edge of the pulse is selected. As the selection of the either edge affects accuracy of the rotational speed measurement, two modes are proposed. One is suitable for a lower speed range in which either of the rising and falling edges is selected for every pulse monitoring period considering the relative phase position of the pulse and the pulse monitoring period. The other is suitable for a higher speed range in which one fixed edge is utilized. Here the edge is selected depending on the winding direction of the electric wire of the pick-up coil of the rotational sensor and independent of the pulse monitoring period.

Abstract: Apparatus for detecting the speed of a moving object when exposed to primary magnetic flux fields and secondary external magnetic flux fields. The apparatus includes a magnetic device which generates the primary magnetic flux fields, a multi-coil device which carries induced electric currents when exposed to the primary magnetic flux field, and an error correction circuit for offsetting the effect of the magnetic flux from the external magnetic flux sources on the induced electric current. A support device is positioned between the multi-coil device and the magnetic device to allow relative movement therebetween, corresponding to the movement of the object.

Abstract: The circuit comprises a comparator 1 fed by a quasi-sinusoidal signal delivered by a source 2 for converting the positive alternations of the signal into pulses acceptable by digital computing means. According to the invention, the circuit comprises a current source 7 selectively connectible to the circuit in order to vary its sensitivity and to thus enable an evaluation of the amplitude of the signal delivered by the source 2. Application to the diagnosis of the operating state of a variable reluctance sensor delivering a quasi-sinusoidal signal representing the speed of rotation of a shaft fitted in a motor vehicle.

Abstract: A speed detector, for use with a tone wheel having metal teeth, employs two coils positioned in offset relation near the tone wheel for interacting with the tone wheel teeth and thus changing their respective inductances. One coil is in a phase sense oscillator circuit and the other is in a tuned sensor network. The oscillator is coupled to, and drives, the tuned network. The change in coil inductances effects a shifting of the phase of the output signal from the oscillator relative to the output signal from the tuned network. The phase sequence of those two output signals also reverses itself cyclically as the tone wheel rotates, and a phase reversal detector detects that reversal and uses the event to provide timing reference pulses for a final determination of speed.

Abstract: The invention relates to an angular measurement device comprising a variable reluctance magnetic circuit comprising a fixed portion (3) associated with a coil (2) and at least a moving element (4) attached to a part (5) rotating in front of the fixed portion, the angular position of which is to be detected, comprising: means (I) for integrating the voltage across the coil, means for measuring the instantaneous value of the integrated voltage (15), means for comparing this measure to a calibrating curve of the integrated voltage versus the angle.

Abstract: A bearing assembly for an axle shaft of a vehicle. An inner ring includes a cylindrical body and an outer flange for mounting a wheel. On a portion of the cylindrical body adjacent the flange is mounted a revolution detection ring which has a seal contact portion and a gear-shaped detected portion having a plurality of projections circumferentially spaced on the outer peripheral surface thereof. The bearing assembly also has an outer ring which is coupled with the inner ring through rolling elements and mounted to the chassis of the vehicle. A sensor is mounted on the outer ring such that it confronts the gear-shaped portion of the revolution detection ring and detects the projections passing by the sensor so as to determine the annular speed of the wheel. The assembly also has a bearing seal which is mounted on the outer ring and kept in contact with the seal contact portion of the revolution detection ring so as to prevent contamination by sand, mud, or the like.

Abstract: A tachometer generator of the inductive pickup variety is disclosed, particularly adapted to be mounted in close proximity with a rotating multipole permanent magnet structure. The coil produces a voltage output proportional to the rate of change and magnitude of the magnetic flux of the rotating magnet. In accordance with this invention, an inductive pickup is disclosed having a core piece which acts as a conduction path for the magnetic field of the rotating magnet and further acts as a means for mounting the inductive pickup within the associated structure. Lead wires are imbedded within the bobbin and form protruding central conductors which act as posts to which each end of the coil wires are electrically and mechanically attached. The lead wires and core piece components are insert molded such that they are loaded into an injection molding die prior to the introduction of plastic material in a molten state which forms the bobbin component.

Abstract: A device for precisely positioning at least one hall effect sensor in a dynamoelectric machine. The hall sensor is mounted in an assembly. The assembly includes an enclosure having at least one locator tang projecting outwardly from the enclosure. The motor includes a stator assembly having a rotor receiving bore formed in it, and a plurality or radially outwardly extending winding receiving slots. The tangs are inserted into at least one slot of the stator assembly. Placement of the device as indicated accurately positions the hall effect sensor for proper motor operation.

Abstract: A device for detecting the rotational speed of a motor by a first rotational speed sensor and at least a second rotational speed sensor and a switch unit connected to the rotational speed sensors, the switch unit selecting signals from one of the sensors within a respective given rotational speed range.

Abstract: A hermetically sealed magnetic sensor for detecting variations in a magnetic field has a sensor element with an output terminal for detecting variations in the magnetic field and generating a signal. An output wire is connected with one end to the terminal for outputting a respective signal from the sensor element. A case having an opening on a side close to the output wire contains the sensor element. A first thermosetting resin fills the case for covering the sensor element. A second thermoplastic resin hermetically seals the opening in the case.

Abstract: An elongated generally cylindrical speed sensing device for sensing the speed of a toothed wheel to one side of the device, the device axis being transverse to the wheel axis and the device being generally tangential to the wheel. An elongated soft magnetic pole piece is surrounded by a coil coaxial with the pole piece, and a laterally extending circular symmetrical pole piece projection extends past an end of the coil to a diameter at least equal to the outside diameter of the coil. An axially magnetized permanent magnet abuts one end of the elongated pole piece. The device housing has rotationally symmetrical mounting surfaces coaxial with the magnetic axis so that angular alignment in installation is not required.

Abstract: The device includes a comparator (4) fed by a quasi-sinusoidal signal (3) delivered by a variable reluctance sensor, for converting alternations of the signal into pulses acceptable by digital computing means. According to the invention, the device includes a selectively connectable feedback resistor (R5) for varying the threshold of the comparator in such a way as to check, at a given frequency of the signal, the correctness of the amplitude of the signal (3) provided by the sensor. The device may be used for the checking of the operational state of a variable reluctance sensor delivering a signal indicating the speed of rotation of a shaft fitted in a motor vehicle.

Abstract: A fractional horsepower permanent magnet direct-current motor has a velocity indicating device positioned around the commutator, between the brush gear and the armature. The device comprises a conductor in the form of a square wave copper strip which is printed on a flexible support and centered on a circle about the motor shaft, and a magnet assembly mounted on the armature. Magnet assembly comprises radially extending blades which are formed from plastics bonded magnetic material. The blades are magnetized so that adjacent blades have opposite polarity. As the magnet rotates with the shaft, the blades move relative to the conductor and so induce an electrical signal in the conductor. The signal can be monitored to indicate the motor speed as is generally known. The blades also act as a centrifugal fan, helping to cool the motor.

Abstract: A rotation sensor for vehicle includes a drive shaft connected to a rotation shaft of a vehicle by a transmission member, a ring-shaped magnet member provided onto the drive shaft and a detector for detecting change of magnetic flux caused by rotations of the magnetic member, wherein rotation frequency or rotation speed can be measured by detecting the changes of the magnetic flux. The magnetic member is formed of a composition of heat resisting resin and magnetic materials, and the formed magnetic member is fixed to the drive shaft through a heat resistant elastic member. As a result, even if the rotation sensor is located in high temperature place, e.g. around an engine, there is no possibility that a crack in the magnet member will be caused since expansion or contraction in the magnetic member can be absorbed by the elastic member.

Abstract: A vehicular drive train includes a torque converter having a bladed impeller element, a bladed turbine element, and a bladed reactor element defining a toroidal chamber within an engine-driven rotating housing. The impeller element is relatively inaccessible because it is contained within the rotating housing, yet it is desirable to monitor its speed in order to better control the operation of the drive train. A speed sensor apparatus is therefore provided which includes a ring magnet connected to rotate with the impeller element, a sensor unit connected to a stationary carrier assembly close to the ring magnet, an external electrical connector, and a wiring harness interconnecting the sensor unit and the electrical connector. Preferably, the sensor unit delivers two digital pulse signals to an associated microprocessor for precise control of the input clutch assembly. The ring magnet and the sensor unit are located radially inwardly of the toroidal chamber such that no additional space is required.