摘要:
A magnetic detection device includes a signal processing circuit that detects a moving position and a moving direction of a magnetic mobile object using an output of a comparing circuit configured to output a signal by comparing an output signal of a magneto-electric transducer element with a threshold. A duration during which an output of the signal processing circuit is in a high level or in a low level is fixed to a period t1 or a period t2 depending on the moving direction of the magnetic mobile object. When switching of the moving direction of the magnetic mobile object takes place within the period t1 or the period t2, the signal processing circuit outputs a position signal same as a position signal indicating a position immediately before the switching of the moving direction of the magnetic mobile object due to hysteresis of the threshold of the comparing circuit.
摘要:
A differential amplifier generates an offset correction signal based on a rotation detection signal from a rotation detector apparatus and an offset signal. A comparator compares the offset correction signal with a threshold voltage, and outputs a binarized signal representing the comparison result. An average value signal generator circuit generates an average value signal representing the average value of the offset correction signal. The offset signal generator circuit generates the offset signal so that the signal voltage of the average value signal has a voltage value between a threshold voltage and a threshold voltage.
摘要:
A differential amplifier generates an offset correction signal based on a rotation detection signal from a rotation detector apparatus and an offset signal. A comparator compares the offset correction signal with a threshold voltage, and outputs a binarized signal representing the comparison result. An average value signal generator circuit generates an average value signal representing the average value of the offset correction signal. The offset signal generator circuit generates the offset signal so that the signal voltage of the average value signal has a voltage value between a threshold voltage and a threshold voltage.
摘要:
A magnetic detection apparatus includes a first comparison circuit that waveform-shapes the amplitude of a detection signal from magneto-electric transducers by DC coupling, a third comparison circuit that waveform-shapes the detection signal by AC coupling, an oscillation circuit having a natural frequency, a control circuit that counts the output of the first comparison circuit by using the oscillation means, and a selection circuit that selects the output of the first comparison means and the output of the second comparison means. The control circuit counts rising from the next rising or falling from the next falling of an output rectangular wave of the first comparison circuit, and provides output to the selection circuit at the time point at which the count value reaches a desired value. The selection circuit selects and outputs the output rectangular wave of the first comparison circuit or the third comparison circuit.
摘要:
Provided is an apparatus for detecting a moving direction that can accurately detect the position, regardless of the moving direction. The moving direction detector includes groups of sensor elements that face a moving body to output detection signals in accordance with travel of the moving body. The detector includes signal processing units that convert output signals of the groups of sensor elements into rectangular waves and a moving direction detection unit that outputs a signal corresponding to a moving direction of the moving body based on the detection signals from the groups of sensor elements. The moving direction detection unit includes a delay function of generating an output signal at a time instant that is delayed by a predetermined time from a time instant when a moving direction of the moving body is changed.
摘要:
In detecting the position and the moving direction of a magnetic moving body, there is provided a moving direction detector that can accurately detect the position, regardless of the moving direction. The moving direction detector is provided with groups of sensor elements that face a moving body (4) and output detection signals in accordance with travel of the moving body (4), each of the groups including one (22) or more sensor elements (21a, 21b); signal processing units (303, 304) that convert output signals of the groups of sensor elements into rectangular waves; a moving direction detection unit (310) that outputs a signal corresponding to a moving direction of the moving body (4), based on the detection signals from the groups of sensor elements; output processing units (307, 308) that output signals with which a moving direction of the moving body can be determined, based on output signals of the signal processing units and an output signal of the moving direction detection unit; and an output determination unit (401) that determines output values of the output processing units. The moving direction detection unit (310) has a delay function of generating an output signal at a time instant that is delayed by a predetermined time from a time instant when a moving direction of the moving body (4) is changed.
摘要:
In a magnetic detection apparatus, a magnetic detection sensor generates a sensor output signal whose high level and low level have different potentials in accordance with the moving direction of a magnetic moving object, and a computer unit includes three comparator circuits and detects the output signal of the magnetic detection sensor with three levels of comparison threshold values, so that the moving direction of the magnetic moving object can be detected accurately without any delay.
摘要:
A distortion of a signal of a magnetic position detection device is reduced so that precise position information at a high degree of accuracy can be obtained. The magnetic position detection device 100 includes a magnetic movable body 10, a bridge circuit 20, a correction circuit 30, and a detection circuit 40. The magnetic movable body 10 is magnetized so that N-poles and S-poles alternately appear and has a region in which distances between the N-poles and the S-poles are constant. The bridge circuit 20 is formed of first, second, third, and fourth field detection portions 2R1, 2R2, 2R3, and 2R4. The correction circuit 30 is formed of fifth and sixth field detection portions 2R5 and 2R6. The detection circuit 40 detects a position of the magnetic movable body 10 on the basis of a differential output Vout of the bridge circuit.
摘要:
A magnetic position detecting device (10) includes a magnet (4); first to fourth magnetoelectric conversion elements (1A to 1D) formed on a virtual plane along a substrate (3); and a flux guide (5) made of a magnetic material. The flux guide (5) includes first and second protrusions (9B, 9A) provided at a distance from each other in the X-axis direction parallel to the virtual plane. As seen in the Z-axis direction perpendicular to the virtual plane, a center portion (MP) recessed in a concave shape is provided in the flux guide (5) in a mid-portion between the first and second protrusions. The first and fourth magnetoelectric conversion elements (1A to 1D) are provided approximately in the mid-portion between the first and second protrusions so as to cover a part of the center portion (MP) as seen in the Z-axis direction. The second magnetoelectric conversion element (1B) is provided between the first protrusion (9B) and the center portion (MP) as seen in the Z-axis direction. The second magnetoelectric conversion element (1B) is provided between the second protrusion (9A) and the center portion (MP) as seen in the Z-axis direction.
摘要:
A magnetic position detection apparatus includes a substrate, a magnet, a bridge circuit including first through fourth magneto-electric converting elements formed on the substrate, and a detection circuit. A substrate surface is substantially perpendicular to a magnet magnetization direction. The second and third magneto-electric converting elements are, when viewed along the magnet magnetization direction, disposed to be on or in the vicinity of a straight line passing through a center point of a magnetic pole of the magnet and parallel to a straight line perpendicular to both the magnet magnetization direction and the magnetic mobile object. The first and fourth magneto-electric converting elements are disposed so that, when not opposed to the magnetic mobile object, a component of a substrate of a magnetic field to be applied thereto is substantially same as that of a magnetic field to be applied to the second and third magneto-electric converting elements.