Abstract:
The present invention relates to a method of manufacturing a sensor rotor with a minimum waste of material. The sensor rotor is manufactured by forming a plurality of ring pieces having outer and inner edges that are identical in curvature to each other, arranging the ring pieces in the shape of a ring, magnetizing the ring pieces to create opposite magnetic poles alternately in the circumferential direction of the ring pieces to form a magnetized ring, and fixing the magnetized ring to the inside of a press-in ring. Since the outer edge of each ring piece substantially coincides with the inner edge of the adjacent ring piece, it is possible to eliminate the waste of material between the adjacent ring pieces.
Abstract:
An inductive displacement sensor comprises a magnetically conductive housing, a coil located within the conductive housing, and a solenoid plunger movable within the coil. A ring-shaped air gap is formed between the solenoid plunger and the conductive housing. A short-circuit ring surrounds the solenoid plunger and is located on the outside of the conductive housing and in front of the ring-shaped air gap. An electronic unit is connected to the coil that measures the displacement-dependent inductance of the coil.
Abstract:
A displacement sensor system is provided which is capable of simultaneously and independently detecting displacements in two directions orthogonal to an axis of an object to be detected, using a less number of displacement sensors than before. The displacement sensor system, for enabling the simultaneous detection of displacements in two directions orthogonal to an axial direction of a pillar-shaped member, has a plurality of displacement sensors positioned around the pillar-shaped member, and a detector circuit for receiving outputs of the plurality of displacement sensors to output signals indicative of displacements in the two directions orthogonal to the axial direction of the pillar-shaped member. The detector circuit includes a multi-bridge circuit for parallelly connecting a circuit having the plurality of displacement sensors connected in series to a plurality of resistor circuits. In one embodiment of the present invention, the pillar-shaped member has a square prism portion, and the plurality of displacement sensors include four displacement sensors, where the displacement sensors are positioned in a plane parallel to a set of opposite surfaces of the square prism portion and in the vicinity of four corners of the square prism portion, respectively. The four displacement sensors are connected in series to form an inductance circuit which constitutes a part of the multi-bridge circuit.
Abstract:
A pointing device includes a plate which is made of a magnetic material and having at least one surface with a regular change in first geometrical configuration along a direction y and a regular change in second geometrical configuration along a direction x which is perpendicular to the direction y, where the change in first geometrical configuration is different from the change in second geometrical configuration, and a coordinate input part slidably provided on the surface of the plate. The coordinate input part comprises a mechanism for generating one of a magnetic flux and magnetic field, and a mechanism for detecting a change in the magnetic flux or magnetic field fed back to the coordinate input part via the plate and generating signals indicating a moving direction and a moving quantity of the coordinate input part on the plate.
Abstract:
An angular displacement sensor for limited angle applications (e.g., for sensing automotive throttle positions) comprising first (14) and second (16) relatively rotatable components arranged to confront each other axially. The first component (14) provides a plurality of poles (14A, B, C) which are angularly disposed about the rotation axis and extend towards the second component. These poles (14A, B, C) have axes which extend in the same direction as the rotation axis. Some poles have windings (14A, B), while others (14B) provide flux return paths. The second component comprises an inductance affecting component (16) which overlies only some of the wound poles at any given time, the relative rotation varying the poles which are overlaid. The sensor includes an output unit (17) for providing output signal data related to the inductances of the excitation poles and thus related to the rotary configuration of the components.
Abstract:
The variable-reluctance servocontrolled linear motor comprises an electromagnet formed by a shell and by a winding around a displacement path, a magnetic portion mobile in the direction of displacement, guided mechanically so as to have a single degree of freedom with respect to the shell, under the effect of the force exerted by the electromagnet. A detector circuit is formed by an inductive or capacitive measurement sensor for the instantaneous value of the air gap and delivers a signal sd representative of the displacement of the mobile magnetic portion. A subtracter circuit receives a displacement control signal e and the signal sd representative of the displacement in order to deliver a displacement error signal .epsilon. for the mobile magnetic portion. A current amplifier circuit receives the error signal .epsilon. and delivers a supply current to the winding. A restoring element for the mobile magnetic portion exerts on the latter a restoring force opposed to the force exerted by the electromagnet. The restoring element can be mechanical or constituted by a counter-electromagnet.
Abstract:
A joystick transducer utilizing a rotating magnetic field within a hollow toroid core, this rotating field drives a polar sensor element to which a 360 degree variable flux coupling element is operated by a joysyick to generate an output signal the phase angle of which corresponds to the azimuth direction of joystick tilt and the amplitude of this same signal corresponds to the magnitude of joystick tilt. A plurality of independent joysticks are also provide on one hollow driving core.
Abstract:
A rotation angle sensor has a cylindrical rotating member attached to a cam shaft of an internal combustion engine for rotation therewith, and a pickup. The rotating member has a portion formed on its inner peripheral surface for detection of a crank angle. The pickup has a column-shaped support portion and is attached coaxially with the rotating member with the support portion rotatably inserted into a hole which is formed in a casing of the internal combustion engine. A detecting portion provided at a distal end of the support portion is positioned inside the rotating member to detect a position of the crank angle detection portion during rotation of the rotating member and output a signal. The pickup further has an arc-shaped elongate hole which is formed to extend about a central axis of the support portion, so that the pickup is fixed to the casing of the internal combustion engine with a bolt inserted through the elongate hole. The pickup, by loosening the bolt, is easily turned to change its angular position with respect to the rotating member. Thus, ignition timing of the internal combustion engine, which is controlled based on the signal from the rotation angle sensor, can be easily adjusted and the structure for the adjustment is simple and inexpensive.
Abstract:
The invention relates to a process and apparatus for detecting the speed and rotary direction of a rotary drive by using a signal-transmitting or signal-changing element which is connected rotationally secured to the rotary drive. According to the invention, during rotation of the signal-transmitting or signal-changing element a rotary direction coded signal is produced which is detected by a sensor and which is supplied to an electronic evaluator unit. The aim of the invention is to provide a process and device for detecting the speed and rotary direction of a rotary drive which manages with one sensor unit for a high analysis of the speed and rotary direction.
Abstract:
A rotary sensing device for indicating the angular displacement of a shaft is disclosed which comprises a magnetic core member formed of ferromagnetic material, a first winding wound within the core member for producing a first magnetic field in a closed path throughout the core, a second winding wound around the core member for producing a second magnetic field in a closed path throughout the core, the first and second magnetic fields being orthogonal to each other, and a pick-up coil assembly associated with the magnetic core member, the magnetic fields, and the shaft for sensing angular displacement of the shaft. A proximity sensor for sensing the passage of an object and the direction of passage of the object is also disclosed.