JP2011059103A - Rotational angle detector, position detector, and detection method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotational angle detector, a position detector, and its detection method for detecting rotational angle or position where the temperature characteristics are good with a simple constitution without using complicated operation such as division and multiplication. <P>SOLUTION: At least two or more physical quantity detecting elements for performing an output proportional to both physical quantity and the element driving amount are used, and a constitution where, in response to rotation or movement of a detecting object, a sine-wave-like physical quantity is applied to one element and a cosine-wave-like physical quantity is applied to the other element is used. The driving quantity of one physical quantity detecting element is driven in the sine-wave shape, that of the other is driven in the cosine-wave shape, the obtained outputs from the physical quantity detecting elements are added to or subtracted from each other, the phase of the obtained output is detected, and rotational angle detection and position detection are performed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a rotation angle detection device, a position detection device, and a detection method thereof, and more specifically, a rotation angle detection device that detects a rotation angle of a rotation angle detection body and a position detection that detects the position of the position detection body. The present invention relates to an apparatus, a rotation angle detection method, and a position detection method.

  For example, when a magnet is used for a detected object (a rotation angle detection object and a detected position object) and a magnetoelectric conversion element is used as a physical quantity detection element, two or more magnetoelectric conversions are performed along with the rotation or movement of the detection object. When a magneto-electric conversion element is driven at a constant amount, a magneto-electric conversion element is applied to the magneto-sensitive surface of the element by applying a sinusoidal magnetic field on one side and a cosine wave-like magnetic field on the other side. A sinusoidal output can be obtained from one of the conversion elements, and a cosine wave output can be obtained from the other.

  As a technique for calculating the rotation angle or position using the sine wave signal and the cosine wave signal obtained in this way, for example, there is a technique as described in Patent Document 1. The method described in Patent Document 1 is a method of calculating a tangent or cotangent by taking a ratio of a sine wave signal and a cosine wave signal, and obtaining an angular position from the obtained value, that is, an arc tangent value or This is a method of obtaining an inverse cotangent value.

  By using such a method, it becomes possible to obtain an output value excellent in temperature characteristics by using a magnetoelectric conversion element with uniform sensitivity, but it is necessary to perform an arithmetic operation, that is, a division, This calculation is not only a cumbersome task for an electronic circuit, but it is difficult to increase its accuracy. In addition, the circuit scale for the division operation is increased.

  Further, as another rotation angle calculation method, for example, as disclosed in Patent Document 2, there is a method using a CORDIC (Coordinating Rotation Digital Computer) algorithm that is also used in an electronic computer or the like. Since this method is digital signal processing, the analog output of the magnetoelectric conversion element or other physical quantity detection element is converted into a digital signal by an AD converter or the like, and then a DSP (digital signal processor) is used. It is necessary to perform digital signal processing, which makes it difficult to reduce the circuit scale.

JP 62-095402 A JP 2005-180942 A

  However, in a general rotation angle detection method or position detection method of a non-contact type rotation angle device or position detection device using a physical quantity detection element such as a magnetoelectric conversion element, a sinusoidal signal obtained from the physical quantity detection element or Using the cosine wave signal, tangent / cotangent calculation, arc tangent / inverse cotangent calculation, etc. are performed to obtain rotation angle or position information of the detected object. Further, tangent / cotangent arithmetic circuits and arc tangent / inverse cotangent arithmetic circuits have been proposed. However, both are methods using multiplication / division circuits and table lookup, and the system or sensor IC becomes complicated, resulting in an increase in the size or cost of the system or sensor IC.

  In addition, generally known magnetic field generated by a non-rotation detector using at least two or more magnetoelectric transducers is changed to a sine wave or cosine wave with rotation. In the method of calculating the rotation angle from the tangent calculation or arc tangent calculation using a configuration that is applied to the part, this sine wave and cosine wave change at the same rate with respect to temperature. Since the rotation angle position is determined by dividing the output of the element, it is known that the temperature characteristic is improved in principle.

  However, in such a method, a division circuit is required for tangent calculation or arc tangent calculation, or a method for avoiding divergence of the tangent calculation value is required.

  The present invention has been made in view of such problems. The object of the present invention is to realize good temperature characteristics with a simple configuration and to perform complicated operations for electronic circuits such as division and multiplication. It is an object of the present invention to provide a rotation angle detection device, a position detection device, and a detection method thereof that realize rotation angle detection and position detection with a simple arithmetic circuit such as addition or subtraction without performing the above.

  The present invention has been made to achieve such an object, and a rotation angle at which a change in a physical quantity that changes to a sine wave signal or a cosine wave signal as the rotation angle detector is rotated is detected by a physical quantity detection element. In the detection device, at least two or more physical quantity detection elements whose output changes in proportion to the change in the physical quantity with the rotation of the rotation angle detection body and in proportion to the drive amount of the physical quantity detection element, One drive unit that applies a physical quantity that changes to a sine wave signal to the physical quantity detection element, and another drive unit that applies a physical quantity that changes to a cosine wave signal to the other physical quantity detection element, and the one physical quantity detection element The output signal obtained by changing the drive amount of the signal to a sine wave signal and the output signal obtained by changing the drive amount of the other physical quantity detection element to a cosine wave signal are calculated. A phase detection unit that detects a phase difference between an output signal of the calculation unit, a drive signal of the one physical quantity detection element, or a drive signal of the other physical quantity detection element, and the phase detection unit And an angle calculation unit that calculates the rotation angle of the rotation angle detector based on the output signal.

  Further, the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.

  Further, a zero cross point detector for detecting a phase difference in the phase detector by zero cross point detection is provided at a subsequent stage of the arithmetic unit.

  In addition, the calculation unit includes an adder or a subtracter.

  Further, the phase detection unit detects a phase difference between the addition value or the subtraction value calculated by the calculation unit and the drive signal.

  Further, the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element.

  The magnetoelectric conversion elements are provided adjacent to each other along with other arithmetic circuits on a Si substrate by circuit integration technology, and the at least two or more magnetoelectric conversion elements have equal output temperature characteristics. And

  Further, the magnetoelectric conversion element is arranged in the vicinity of the end of the lower surface of the magnetic convergence plate.

  Further, in a position detection device that detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal as the position detection body moves, the physical quantity change caused by the movement of the position detection body. At least two or more physical quantity detection elements whose output changes in proportion to the drive quantity of the physical quantity detection element, and one drive unit that applies a physical quantity that changes to a sinusoidal signal to the one physical quantity detection element The other drive unit for applying a physical quantity that changes to a cosine wave signal to the other physical quantity detection element, an output signal obtained by changing the drive quantity of the one physical quantity detection element to a sine wave signal, and A calculation unit that calculates an output signal obtained by changing the drive amount of the other physical quantity detection element into a cosine wave signal, an output signal of the calculation unit, and the one physical quantity detection element A phase detection unit that detects a phase difference from a motion signal or a drive signal of the other physical quantity detection element; and a position calculation unit that calculates a movement amount of the position detection object based on an output signal of the phase detection unit; It is provided with.

  Further, in a rotation angle detection device that detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the rotation of a gear tooth that is a rotation angle detector, the physical quantity detection element detects the change in the gear tooth as the gear tooth rotates. The first to fourth physical quantity detection elements whose output changes in proportion to the change in physical quantity and in proportion to the drive quantity of the physical quantity detection element, and the first and third physical quantity detection elements change to sinusoidal signals. One driving unit that applies a physical quantity to be applied, the other driving unit that applies a physical quantity changing to a cosine wave signal to the second and fourth physical quantity detection elements, and driving the first and third physical quantity detection elements A signal obtained by subtracting an output signal obtained by changing the quantity into a sine wave signal, and an output signal obtained by changing the drive quantity of the second and fourth physical quantity detection elements into a cosine wave signal Subtract An arithmetic unit that calculates the obtained signal, an output signal of the arithmetic unit, a driving signal of the first and third physical quantity detection elements, or a driving signal of the second and fourth physical quantity detection elements A phase detection unit that detects a phase difference and an angle calculation unit that calculates a rotation angle of the gear teeth based on an output signal from the phase detection unit.

  A subtractor is provided in the preceding stage of the arithmetic unit.

  The plurality of magnetoelectric transducers are arranged at intervals of a pitch d / 4 of the gear teeth.

  Further, in a position detection device that detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the movement of a gear tooth that is a position detection body, in the position detection device, the physical quantity of the physical quantity that accompanies the movement of the gear tooth. The first to fourth physical quantity detection elements whose output changes in proportion to the change and in proportion to the driving amount of the physical quantity detection element, and the physical quantity that changes to a sinusoidal signal in the first and third physical quantity detection elements A drive unit that applies a physical quantity that changes to a cosine wave signal to the second and fourth physical quantity detection elements, and a drive quantity of the first and third physical quantity detection elements. Subtract the signal obtained by subtracting the output signal obtained by changing to a sine wave signal and the output signal obtained by changing the drive amount of the second and fourth physical quantity detection elements to a cosine wave signal. Obtained A phase difference between a calculation unit that calculates a signal, an output signal of the calculation unit, a drive signal of the first and third physical quantity detection elements, or a drive signal of the second and fourth physical quantity detection elements A phase detection unit for detection and a position calculation unit for calculating a movement amount of the gear teeth based on an output signal of the phase detection unit are provided.

  Further, in the rotation angle detection method for detecting a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the rotation of the rotation angle detector, the physical quantity that accompanies the rotation of the rotation angle detector. And using at least two or more physical quantity detection elements whose output changes in proportion to the drive quantity of the physical quantity detection element, and applies a physical quantity that changes to a sinusoidal signal to the one physical quantity detection element Applying a physical quantity that changes to a cosine wave signal to the other physical quantity detection element; an output signal obtained by changing the drive amount of the one physical quantity detection element to a sine wave signal; and the other physical quantity detection element. A step of calculating an output signal obtained by changing a drive amount of the physical quantity detection element into a cosine wave signal, an output signal of the calculation unit, and the one physical quantity A step of detecting a phase difference between a drive signal of the output element or a drive signal of the other physical quantity detection element, and a step of calculating a rotation angle of the rotation angle detector based on an output signal from the phase detection unit It is characterized by having.

  Further, the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.

  Further, a zero cross point detecting step for performing phase difference detection in the step of detecting the phase difference by zero cross point detection is provided after the calculating step.

  The step of calculating includes a step of adding or subtracting.

  The step of detecting the phase difference is characterized by detecting a phase difference between the addition value or subtraction value calculated in the step of calculating and the drive signal.

  Further, the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element.

  Further, in the position detection method for detecting a change in physical quantity that changes to a sine wave signal or a cosine wave signal with the movement of the position detection object by a physical quantity detection element, the change in the physical quantity with the movement of the position detection object. Applying at least two or more physical quantity detection elements whose outputs change in proportion to the drive quantity of the physical quantity detection element, and applying a physical quantity that changes to a sinusoidal signal to the one physical quantity detection element; Applying a physical quantity that changes to a cosine wave signal to the other physical quantity detection element; an output signal obtained by changing a drive quantity of the one physical quantity detection element to a sine wave signal; and the other physical quantity detection element Calculating the output signal obtained by changing the drive amount of the signal into a cosine wave signal, the output signal of the calculation unit, and the drive of the one physical quantity detection element. A step of detecting a phase difference between a signal or a drive signal of the other physical quantity detection element, and a step of calculating a position of the position detection body based on an output signal from the phase detection unit. And

  Further, in the rotation angle detection method in which a physical quantity detection element detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal along with the rotation of the gear tooth that is the rotation angle detection body, the rotation angle detection method includes: The first to fourth physical quantity detection elements whose outputs change in proportion to changes in the physical quantity and in proportion to the driving amount of the physical quantity detection element are used, and sinusoidal signals are used for the first and third physical quantity detection elements. Applying a changing physical quantity; applying a physical quantity changing to a cosine wave signal to the second and fourth physical quantity detection elements; and driving amount of the first and third physical quantity detection elements as a sine wave signal Obtained by subtracting the output signal obtained by subtracting the output signal obtained by changing the driving amount of the second and fourth physical quantity detection elements into a cosine wave signal. And a phase difference between the output signal of the calculation unit and the drive signals of the first and third physical quantity detection elements or the drive signals of the second and fourth physical quantity detection elements And a step of calculating a rotation angle of the gear teeth based on an output signal from the phase detector.

  Further, in a position detection method in which a physical quantity detection element detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the movement of a gear tooth that is a position detection object, the physical quantity of the physical quantity that accompanies the movement of the gear tooth. Using the first to fourth physical quantity detection elements whose output changes in proportion to the change and in proportion to the driving amount of the physical quantity detection element, the first and third physical quantity detection elements change to sinusoidal signals. Applying a physical quantity; applying a physical quantity that changes to a cosine wave signal to the second and fourth physical quantity detection elements; and changing a drive quantity of the first and third physical quantity detection elements to a sine wave signal. Obtained by subtracting the output signal obtained by subtracting the output signal obtained by subtracting the signal obtained by subtracting the drive amount of the second and fourth physical quantity detection elements into a cosine wave signal. Trust And a phase difference between the output signal of the calculation unit and the drive signals of the first and third physical quantity detection elements or the drive signals of the second and fourth physical quantity detection elements And a step of calculating the position of the gear teeth based on an output signal from the phase detector.

  According to the present invention, it is possible to perform rotation angle detection and position detection without using a complicated and huge system or signal processing circuit, and without requiring a large circuit area while avoiding complexity compared to the prior art. Further, by reducing the necessary circuit blocks, it becomes possible to reduce the angle error caused by the circuit blocks and shorten the sensor mass production inspection time.

It is a block block diagram for demonstrating embodiment of the rotation angle detection apparatus and position detection apparatus which concern on this invention. It is a perspective view for demonstrating the rotation detection operation | movement in the rotation angle detection apparatus which concerns on Example 1 of this invention. It is the figure which looked at FIG. 2 from the lower surface, and is the figure which showed the positional relationship with the magnetoelectric conversion element at the time of the rotation angle position 0 degree of a to-be-rotated angle detection body (magnet). It is the figure which looked at FIG. 2 from the lower surface, and is the figure which showed the positional relationship with the magnetoelectric conversion element at the time of the rotation angle position of 15 degrees of a to-be-rotated angle detection body (magnet). FIG. 3 is a diagram of FIG. 2 as viewed from below, and is a diagram illustrating a positional relationship with a magnetoelectric conversion element at a rotation angle position of 30 ° of a rotation angle detector (magnet). It is a figure which shows the time change of the drive amount of the magnetoelectric conversion element in the rotation detection operation | movement shown in FIG. It is a figure which shows the change of the magnetic field intensity applied to each of the magnetoelectric conversion element with rotation of the to-be-rotated angle detection body shown in FIG. It is a figure which shows the output of each magnetoelectric conversion element in the rotation angle position 0 degree of the to-be-rotated angle detection body shown in FIG. It is a figure which shows the result of mutually adding the output of each magnetoelectric conversion element in the rotation angle position 0 degree of the to-be-rotated angle detection body shown in FIG. It is a figure which shows the output of each magnetoelectric conversion element in rotation angle position 15 degrees of the to-be-rotated angle detection body shown in FIG. It is a figure which shows the result of mutually adding the output of each magnetoelectric conversion element in the rotation angle position 15 degrees of the to-be-rotated angle detection body shown in FIG. It is a figure which shows the output of each magnetoelectric conversion element in the rotation angle position 30 degrees of the to-be-rotated angle detection body shown in FIG. It is a figure which shows the result of mutually adding the output of each magnetoelectric conversion element in the rotation angle position 30 degrees of the to-be-rotated angle detection body shown in FIG. It is a figure which shows the difference in the phase by the result in the rotation angle position of each to-be-rotated angle detection body shown in FIG.9, FIG11 and FIG.13. It is a figure for demonstrating the modification of Example 1 of the rotation detection operation | movement in the rotation angle detection apparatus which concerns on this invention, (a) is a bottom view, (b) has shown the side view. It is a figure which shows the time change of the drive amount of the magnetoelectric conversion element in this invention, and is a figure which shows an example of the pseudo sine wave drive or cosine wave drive (current drive) which can be substituted for FIG. It is a figure for showing the time change of the drive amount of the magnetoelectric conversion element in the present invention, and is a figure showing an example of other pseudo sine wave drive or cosine wave drive which can be substituted for FIG. It is a figure for showing the time change of the drive amount of the magnetoelectric conversion element in this invention, and is a figure which shows an example of the further another pseudo sine wave drive or cosine wave drive which can be substituted for FIG. It is a figure for demonstrating the position detection operation | movement in the position detection apparatus which concerns on Example 2 of this invention. It is a figure which shows the change of the magnetic field intensity applied to each of the magnetoelectric conversion element accompanying the linear motion movement of the to-be-positioned detection body (magnet) shown in FIG. It is a figure which shows a mode that the time from the drive start of the magnetoelectric conversion element in this invention to the zero crossing point from which the sign of an addition result value changes from positive to negative changes with magnet angle positions. It is a figure which shows the angle error generation amount at the time of driving with the pseudo sine wave shown in FIG. It is a figure which shows an example of the method of producing the pseudo sine wave shown in FIG.16 and FIG.24. It is a figure which shows the time change of the drive amount of the magnetoelectric conversion element in this invention, and is a figure which shows an example of the pseudo sine wave drive or cosine wave drive (voltage drive) which can be substituted for FIG. It is a block diagram for demonstrating rotation detection operation | movement of the gear tooth in the rotation angle detection apparatus which concerns on Example 3 of this invention. It is a block block diagram for demonstrating embodiment of the rotation angle detection apparatus and movement amount detection apparatus of the gear tooth which concern on this invention. It is a figure which shows the change of the applied magnetic flux density of the magnetoelectric conversion element with respect to the rotation amount of a gear tooth. It is a figure which shows the time change of the drive amount of the magnetoelectric conversion element in rotation or movement detection operation | movement of the gear tooth shown in FIG.25 and FIG.36. It is a figure which shows the output of each magnetoelectric conversion element in case the rotation amount of the gear tooth in FIG. 25 is 0 degree. It is a figure which shows the result of subtracting the output of the magnetoelectric conversion elements 1 and 3 and the magnetoelectric conversion elements 2 and 4 when the rotation amount of the gear teeth in FIG. 25 is 0 °. It is a figure which shows the output of each magnetoelectric conversion element in case the rotation amount of the gear tooth in FIG. 25 is 0.9375 degrees. It is a figure which shows the result of having subtracted the output of the magnetoelectric conversion elements 1 and 3 and the magnetoelectric conversion elements 2 and 4 when the rotation amount of the gear teeth in FIG. 25 is 0.9375 °. It is a figure which shows the output of each magnetoelectric conversion element in case the rotation amount of the gear tooth in FIG. 25 is 1.875 degrees. It is a figure which shows the result of having subtracted the output of the magnetoelectric conversion elements 1 and 3 and the magnetoelectric conversion elements 2 and 4 when the rotation amount of the gear teeth in FIG. 25 is 1.875 °. It is a figure which shows the result of having added together the result which subtracted the output of the magnetoelectric conversion elements 1 and 3 and the magnetoelectric conversion elements 2 and 4 in each rotation amount of the gear tooth in FIG. It is a block diagram for demonstrating the movement detection operation | movement of the gear tooth in the rotation angle detection apparatus which concerns on Example 4 of this invention. It is a figure which shows the change of the applied magnetic flux density of the magnetoelectric conversion element with respect to the movement amount of the gear tooth in FIG. It is a figure which shows the output of each magnetoelectric conversion element in case the moving amount | distance of the gear tooth in FIG. 36 is 0 mm. It is a figure which shows the result of having subtracted the output of the 1st and 3rd magnetoelectric conversion element and the 2nd and 4th magnetoelectric conversion element in case the moving amount | distance of the gear tooth in FIG. 36 is 0 mm. It is a figure which shows the output of each magnetoelectric conversion element in case the moving amount | distance of the gear tooth in FIG. 36 is 15 mm. It is a figure which shows the result of having subtracted the output of the 1st and 3rd magnetoelectric conversion element and the 2nd and 4th magnetoelectric conversion element in case the moving amount | distance of the gear tooth in FIG. 36 is 15 mm. It is a figure which shows the output of each magnetoelectric conversion element when the movement amount of the gear tooth in FIG. 36 is 30 mm. It is a figure which shows the result of subtracting the output of the 1st and 3rd magnetoelectric conversion element and the 2nd and 4th magnetoelectric conversion element in case the moving amount | distance of the gear tooth in FIG. 36 is 30 mm. It is a figure which shows the result of having added together the result which subtracted the output of the 1st and 3rd magnetoelectric conversion element and the 2nd and 4th magnetoelectric conversion element in each moving amount | distance of the gear tooth in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a block diagram for explaining an embodiment of a rotation angle detection device and a position detection device according to the present invention. In FIG. 1, reference numeral 1 denotes a first physical quantity detection element (magnetoelectric conversion element), and 2 denotes a second. , A sine wave drive unit, 7 a cosine wave drive unit, 8 a calculation unit, 9 (91, 92) a zero cross point detection unit and a counter, 10 a counter value output unit (Phase detector), 11 is a rotation angle calculator, and 12 is a position calculator.

<Rotation angle detector>
The rotation angle detection device of the present invention detects a change in a physical quantity that changes into a sine wave signal or a cosine wave signal as the rotation angle detector (magnet) rotates, by a physical quantity detection element (magnetoelectric conversion element). . The output of the first and second physical quantity detection elements is proportional to the change in the physical quantity accompanying the rotation of the rotation angle detector and the output changes in proportion to the drive amount of the physical quantity detection element.

  The sine wave drive unit 6 applies a physical quantity that changes to a sine wave signal to the first physical quantity detection element 1, and the cosine wave drive unit 7 applies a physical quantity that changes to a cosine wave signal to the second physical quantity detection element 2. To do.

  The calculation unit 8 is obtained by changing the drive amount of the first physical quantity detection element 1 into a sine wave signal and changing the drive amount of the second physical quantity detection element 2 into a cosine wave signal. The output signal is calculated.

  The zero cross point detection unit and counter 9 (91, 92) includes a zero cross point detection unit 91 for detecting a phase difference in the counter value output unit (phase detection unit) 10 by zero cross point detection, and a drive start time. And a counter 92 that measures the time from the value obtained by the calculation unit 8 to the zero cross point. The counter value output unit (phase detection unit) 10 is for outputting the value obtained by the counter 92. Further, the phase detection unit 10 detects a phase difference between the output signal of the calculation unit 8 and the drive signal of the first physical quantity detection element 1 or the drive signal of the second physical quantity detection element 2.

  The rotation angle calculation unit 11 calculates a rotation angle of the rotation angle detection body based on an output signal from the counter value output unit (phase detection unit) 10 to obtain a rotation angle output.

  Thus, according to the present invention, by using a physical quantity detection element having the same sensitivity, it is possible to obtain a sine wave or cosine wave output whose phase changes in proportion to the rotation of the rotation angle detector. It becomes possible. Further, by using physical quantity detection elements formed on the same IC and having substantially the same temperature characteristics, the phase of this output becomes an output having no temperature dependency.

  In addition, by detecting the zero cross point of the sine wave or cosine wave output whose phase changes in proportion to the rotation of the rotation angle detector, the phase change amount can be easily detected using, for example, a comparator. It is possible to obtain an output with less temperature characteristics.

  Further, by arranging the magnetoelectric conversion element in the vicinity of the end of the lower surface of the magnetic converging plate, the magnetic converging plate collects the surrounding magnetic flux, and the collected magnetic flux is applied to the magnetoelectric conversion element. By adopting such a form, it becomes possible to convert a horizontal magnetic field component into a vertical magnetic field component with respect to the magnetosensitive surfaces of the magnetoelectric conversion element 1 and the magnetoelectric conversion element 2. That is, a magnetic field parallel to the paper surface at the position of the magnetoelectric conversion element 1 and the magnetoelectric conversion element 2 can be converted into a magnetic field perpendicular to the paper surface by the magnetic converging plate 14. Therefore, it is suitable when a Hall element that detects only a magnetic field component perpendicular to the magnetosensitive surface of the magnetoelectric conversion element 1 and the magnetoelectric conversion element 2 is selected as the magnetoelectric conversion element. It is also possible to collect the surrounding magnetic flux and amplify the magnetic flux density applied to the magnetosensitive surface of the magnetoelectric transducer.

<Position detection device>
The position detection device of the present invention detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the movement of a position detection body (magnet) by a physical quantity detection element (magnetoelectric conversion element). The first and second physical quantity detection elements 1, 2 are proportional to the change in physical quantity accompanying the movement of the position detection object, and the output changes in proportion to the drive quantity of the physical quantity detection element.

  The sine wave drive unit 6 applies a physical quantity that changes to a sine wave signal to the first physical quantity detection element 1. The cosine wave drive unit 7 applies a physical quantity that changes to a cosine wave signal to the second physical quantity detection element 2.

  The calculation unit 8 is obtained by changing the drive amount of the first physical quantity detection element 1 into a sine wave signal and changing the drive amount of the second physical quantity detection element 2 into a cosine wave signal. The output signal is calculated.

  The zero cross point detection unit and counter 9 (91, 92) includes a zero cross point detection unit 91 for detecting a phase difference in the counter value output unit (phase detection unit) 10 by zero cross point detection, and a drive start time. And a counter 92 that measures the time from the value obtained by the calculation unit 8 to the zero cross point. The counter value output unit (phase detection unit) 10 is for outputting the value obtained by the counter 92. Further, the phase detection unit 10 detects a phase difference between the output signal of the calculation unit 8 and the drive signal of the first physical quantity detection element 1 or the drive signal of the second physical quantity detection element 2.

  The position calculation unit 12 calculates the amount of movement of the position detection body based on the output signal of the counter value output unit (phase detection unit) 10 to obtain a position output.

  According to the present invention, a physical quantity such as magnetic flux density can be applied to a magnetoelectric conversion element without electric power by using a magnet as a position detection body and using a magnetoelectric conversion element as a physical quantity detection element. As compared with a light source required when using a light quantity as a physical quantity, it can be used in a wide temperature range and can provide a detection method with a long lifetime.

  The sine wave signal described above includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal. Since the above-described sine wave and cosine wave are not realistic because the circuit scale becomes large when actually manufactured on an IC, pseudo sine wave drive or cosine wave drive using a pseudo sine wave or cosine wave is not practical. It is realistic to use The calculation unit 8 includes an adder or a subtracter.

  When a magnetoelectric conversion element is used as the physical quantity detection element, the magnetoelectric conversion element is provided adjacent to each other together with other arithmetic circuits on the Si substrate by circuit integration technology, and at least two or more magnetoelectric conversion elements are equal. Has output temperature characteristics.

  In addition, the magnetoelectric conversion element is disposed in the vicinity of the end of the lower surface of the magnetic convergence plate. The magnetic focusing plate collects the magnetic flux around it, and the collected magnetic flux is applied to the magnetoelectric conversion element. By taking this form, the magnetoelectric conversion can detect only the magnetic field component perpendicular to the magnetosensitive surface. When the element is used, the magnetic flux component parallel to the magnetic sensing surface of the position detection device can be converted into a vertical component, which is suitable for the position detection device.

  Hereinafter, a specific rotation angle detection device (Example 1) and a position detection device (Example 2) of the present invention will be described.

  The first embodiment relates to a rotation angle detection device when the physical quantity is the magnetic field intensity and the physical quantity detection element is a magnetoelectric conversion element. The block diagram for explaining the rotation angle detection device in the first embodiment is the same as FIG. 1 described above.

  FIG. 2 is a perspective view for explaining a rotation detection operation in the rotation angle detection apparatus according to the first embodiment of the present invention. In the figure, reference numeral 1 is a first magnetoelectric conversion element, 2 is a second magnetoelectric conversion element, 3 is a rotated angle detector (magnet) having N and S poles, 4 is a rotating shaft of the rotated angle detector, Reference numeral 5 denotes a rotation direction, and an arrow denotes a magnetic sensing direction of the magnetoelectric conversion element. The first magnetoelectric conversion element 1 and the second magnetoelectric conversion element 2 are respectively arranged on the XY axes in the vicinity of the rotation angle detector 3.

  FIG. 3 is a view of FIG. 1 as viewed from below, and is a diagram showing a positional relationship with the magnetoelectric conversion element when the rotation angle detector (magnet) has a rotation angle position of 0 °. That is, the rotation angle detector 3 is not rotated with respect to the first magnetoelectric conversion element 1 and the second magnetoelectric conversion element 2 arranged on the XY axis, and the rotation angle is 0 °. ing.

  FIG. 4 is a view of FIG. 1 as viewed from below, and is a view showing a positional relationship with the magnetoelectric conversion element when the rotation angle detector (magnet) has a rotation angle position of 15 °. That is, the rotation angle detector 3 is rotated with respect to the first magnetoelectric conversion element 1 and the second magnetoelectric conversion element 2 arranged on the XY axis, and the rotation angle is 15 °. Yes.

  FIG. 5 is a diagram of FIG. 1 as viewed from below, and is a diagram illustrating a positional relationship with the magnetoelectric conversion element when the rotation angle detector (magnet) has a rotation angle position of 30 °. That is, the rotation angle detector 3 is rotated with respect to the first magnetoelectric conversion element 1 and the second magnetoelectric conversion element 2 arranged on the XY axis, and the rotation angle is 30 °. Yes.

  Next, functions of each part of the first embodiment will be described.

  The first and second magnetoelectric transducers 1 and 2 are arranged immediately below the circumference of the rotation angle detector (magnet) 3 and are arranged 90 ° out of phase on the same plane. Yes.

  FIG. 6 is a diagram showing a temporal change in the driving amount of the magnetoelectric conversion element in the rotation detection operation shown in FIG. 1, and the first and second magnetoelectric conversion elements 1 and 2 are as shown in FIG. , One is driven in a sine wave, and the other is driven in a cosine wave. In addition, when the rotated angle detector (magnet) 3 rotates in any one of the rotation directions 5 of the rotated angle detector, the rotation angle detector (magnet) 3 depends on the angular position of each of the magnetoelectric transducers 1 and 2. The magnetic field strength is applied as shown in FIG.

  FIG. 7 is a diagram showing changes in the magnetic field strength applied to each of the magnetoelectric transducers as the rotation angle detector shown in FIG. 2 rotates, and the rotation angle detector (FIG. 3 to FIG. 5) described above. The state of the change of the magnetic field intensity applied to the 1st and 2nd magnetoelectric conversion elements 1 and 2 accompanying rotation of a magnet is shown. The outputs of the magnetoelectric conversion elements 1 and 2 are proportional to the drive amount of the magnetoelectric conversion elements 1 and 2 and the magnetic field strength applied to the magnetoelectric conversion elements 1 and 2. That is, the output of the magnetoelectric conversion element = k (proportional constant) × drive amount × applied magnetic field strength.

  That is, as shown in FIG. 3 to FIG. 5, as the rotation angle detector rotates, a magnetic field as shown in FIG. 7 is applied to each of the magnetoelectric conversion elements 1 and 2 according to the angular position. Is done. Here, the positional relationship as shown in FIG. 3 is defined as 0 °, but any position may be 0 °. In addition, the auxiliary line “A” in the figure indicates the rotation angle position of the rotated angle detector shown in FIG. 3 at 0 °, and “B” indicates the rotation angle position of the rotated angle detector shown in FIG. 15 ° is indicated, and “C” indicates the rotation angle position of the rotated angle detector shown in FIG. 5 at 30 °.

  Here, since the output of the magnetoelectric conversion elements 1 and 2 has an output proportional to the magnetic field strength applied to the magnetosensitive surfaces of the magnetoelectric conversion elements 1 and 2 and the driving amount, for example, for the magnetoelectric conversion element 1 When the magnetoelectric conversion element 1 is driven in a sine wave form by the sine wave driving unit 6 and the magnetoelectric conversion element 2 is driven in a cosine wave form by the cosine wave driving unit 7 for the magnetoelectric conversion element 2, the magnetoelectric conversion element 1, When the magnetoelectric transducer is driven with a magnetic sensitivity of 2 mV / (mT · mA) (1 mA drive amount), this means that if a magnetic field strength of 1 mT is applied to the magnetoelectric transducer, it has an output of 1 mV. .) When the angular position of the rotation angle detector is 0 °, the outputs obtained from the respective magnetoelectric transducers 1 and 2 are as shown in FIG.

  FIG. 8 is a diagram showing the output of each magnetoelectric conversion element at the rotation angle position 0 ° of the rotation angle detector shown in FIG. Referring to FIG. 7, when the rotation angle position of the rotated angle detector is 0 ° (auxiliary line A), the magnetic field strength applied to the magnetoelectric conversion element 1 is 50 mT, while the magnetoelectric conversion element 2 The magnetic field strength applied to the magnetoelectric conversion elements 1 and 2 is proportional to the drive amount of the magnetoelectric conversion elements 1 and 2 and the magnetic field strength. The output obtained from 1 and 2 is as shown in FIG. That is, the output of the magnetoelectric conversion element 1 changes in a sine wave shape, and the output of the magnetoelectric conversion element 2 is zero.

  FIG. 9 is a diagram showing a result of adding the outputs of the respective magnetoelectric conversion elements at the rotation angle position 0 ° of the rotated angle detection body shown in FIG. 1, and each of the magnetoelectric conversion elements shown in FIG. It is a figure which shows the result of having added the output of these.

  The results obtained by adding the outputs of the respective magnetoelectric conversion elements 1 and 2 thus obtained by the calculation unit 8 for adding the outputs of the magnetoelectric conversion elements 1 and 2 are as shown in FIG. Become. That is, a sine wave output is obtained.

  Similarly, the output obtained from each magnetoelectric conversion element when the rotation angle position of the rotation angle detector is 15 ° is as shown in FIG.

  FIG. 10 is a diagram showing the output of each magnetoelectric conversion element at the rotation angle position of 15 ° of the rotation angle detector shown in FIG. Referring to FIG. 7, when the angular position of the rotation angle detector is 15 ° (auxiliary line B), the magnetic field strength applied to the magnetoelectric transducer 1 is about 48.3 mT (cos (15 °) × 50 mT). On the other hand, the magnetic field intensity applied to the magnetoelectric conversion element 2 is about 12.9 mT (Sin (15 °) × 50 mT), and the output obtained from the magnetoelectric conversion elements 1 and 2 is the magnetoelectric conversion element. Therefore, the outputs obtained from the magnetoelectric conversion elements 1 and 2 are as shown in FIG.

  The outputs of the respective magnetoelectric conversion elements 1 and 2 thus obtained are added by the calculation unit 8 of the outputs of the magnetoelectric conversion elements 1 and 2 for adding the outputs of the magnetoelectric conversion element 1 and the magnetoelectric conversion element 2. The result is as shown in FIG.

  FIG. 11 is a diagram showing the result of adding the outputs of the respective magnetoelectric conversion elements at the rotation angle position of 15 ° of the rotation angle detector shown in FIG. 1, and each of the magnetoelectric conversion elements shown in FIG. It is a figure which shows the result of having added the output of these.

  Similarly, the output obtained from each magnetoelectric conversion element when the rotation angle position of the rotation angle detector is 30 ° is as shown in FIG.

  FIG. 12 is a diagram showing the output of each magnetoelectric conversion element at the rotation angle position 30 ° of the rotation angle detector shown in FIG. Referring to FIG. 7, when the rotation angle position of the rotation angle detector is 30 ° (auxiliary line C), the magnetic field strength applied to the magnetoelectric transducer 1 is about 43.3 mT (cos (30 °) × 50 mT). On the other hand, the magnetic field strength applied to the magnetoelectric conversion element 2 is 25 mT (Sin (30 °) × 50 mT), and the output obtained from the magnetoelectric conversion elements 1 and 2 is the driving amount of the magnetoelectric conversion element. Therefore, the outputs obtained from the magnetoelectric conversion elements 1 and 2 are as shown in FIG.

  The outputs of the respective magnetoelectric conversion elements 1 and 2 thus obtained are added by the calculation unit 8 of the outputs of the magnetoelectric conversion elements 1 and 2 for adding the outputs of the magnetoelectric conversion element 1 and the magnetoelectric conversion element 2. The result is as shown in FIG.

  FIG. 13 is a diagram showing a result of adding the outputs of the respective magnetoelectric conversion elements at the rotation angle position of 30 ° of the rotated angle detector shown in FIG. 1, and each of the magnetoelectric conversion elements shown in FIG. It is a figure which shows the result of having added the output of these.

  Here, it can be seen from FIGS. 9, 11 and 13 that are the addition results at the respective rotation angle positions that the phase shifts in proportion to the increment of the rotation angle position.

  FIG. 14 is a diagram showing the phase difference depending on the result at the rotation angle position of each rotation angle detector shown in FIG. 9, FIG. 11, and FIG. 13, and shown in FIG. 9, FIG. 11, and FIG. It is a figure which puts together the calculation output result in this rotation angle position, and shows the change of a phase.

  That is, FIG. 14 is a diagram in which FIGS. 9, 11, and 13 are collectively shown, but it can be seen that the phase changes in proportion to the change in the magnet angular position, that is, It can be seen that each phase shift corresponds to the angle shift.

This calculation is performed using B: magnet magnetic field strength [mT], K: constant current sensitivity of the magnetoelectric conversion element [mV / (mT · mA)], Isin α (t): driving current of the magnetoelectric conversion element 1, I cos α (t): When the drive current of the magnetoelectric conversion element 2 is t: time [ms], θ: magnet angular position [°], the output value of the magnetoelectric conversion element 1 is V _HALL1 and the output value of the magnetoelectric conversion element 2 is V _HALL2 Then, from the trigonometric addition theorem, the following equation (1)

  The above calculation result shows that a sine wave whose amplitude is B · K · I and whose phase is shifted by the angle θ of the magnet is obtained as a function of time t. . Therefore, an output proportional to the angular position of the magnet can be obtained by outputting the phase of the sine wave obtained by this calculation as the calculation result. In addition, this phase is measured, for example, from the drive start time to the zero cross point of the addition result (sine wave that can be expressed as a function of time t) obtained by the calculation unit 8 of the output of the magnetoelectric conversion elements 1 and 2. The counter 92 can be easily detected by observing the time until the zero cross point. Further, when detecting the zero cross point, the sign of the addition result value obtained by the calculation unit 8 changes from positive to negative, or the point where the sign changes from negative to positive. It can be detected.

  FIG. 21 shows how the time from the start of driving to the zero cross point of the addition result (the point where the sign of the addition result value changes from positive to negative) varies depending on the magnet angle position.

  FIG. 21 is a diagram showing how the time from the start of driving of the magnetoelectric transducer according to the present invention to the zero cross point at which the sign of the addition result value changes from positive to negative changes depending on the magnet angular position. From this graph, it can be seen that the time (ie, phase) from the start of driving to the zero cross point of the addition result value also changes correspondingly in proportion to the change in the magnet angular position, that is, the zero cross point is observed. This shows that the rotational angle position of the magnet can be identified.

  Moreover, although what was mentioned above added the output value of the mutual magnetoelectric conversion elements 1 and 2 and obtained the calculation result, the output proportional to the rotation angle position of the magnet can be obtained also by subtraction. Is possible. The waveform obtained by subtraction is expressed by the following equation (2).

  It becomes.

  In addition, each configuration such as the arithmetic unit 8 may be implemented by an analog circuit or a digital circuit.

  FIG. 16 is a diagram showing a temporal change in the drive amount of the magnetoelectric conversion element in the present invention, and is a diagram showing an example of pseudo sine wave drive or cosine wave drive that can be substituted for FIG. In other words, the above-described sine wave and cosine wave are not realistic because the circuit scale and the like are large when actually manufactured on an IC. Therefore, pseudo sine wave driving or cosine driving with a pseudo sine wave or cosine wave is not possible. It is practical to use wave driving.

  FIG. 23 is a diagram illustrating an example of a method for creating the pseudo sine wave illustrated in FIGS. 16 and 24. When driving with a current amount as shown in FIG. 16, it can be easily implemented by converting the output of an example of the method shown in FIG. The current amounts of the constant current sources ICC1 to ICC4 are such that ICC1: ICC2 = 1: √2, ICC3: ICC4 = 1: 1: √2, ICC1 = ICC3, and an electrical angle of 0 to 45 °. The section closes only SW1 and SW2, the section from electrical angle 45 to 90 ° closes only SW1, the section from electrical angle 90 to 135 ° closes only SW3, and the electrical angle from 135 to 225 ° The section closes only SW3 and SW4, the section up to electrical angle 225-290 ° closes only SW3, the section up to electrical angle 290-315 ° closes only SW1, and the electrical angle up to 315-360 ° In the section, by closing only SW3 and SW4, a pseudo sine wave as shown in FIG. 16 can be created. Further, since the pseudo cosine wave is only 90 ° out of phase with the sine wave, it can be created by shifting the timing of closing the SW in the same circuit.

  As described above, FIG. 23 is a diagram showing an example of a method for creating the pseudo sine wave shown in FIGS. 16 and 24, FIG. 16 is an example of current driving, and FIG. 24 is an example of voltage driving. Needless to say, any driving example can be applied to the present invention. When current driving is performed as shown in FIG. 16, it can be easily carried out by performing voltage-current conversion on the output of an example of the technique shown in FIG.

[Modification of Example 1]
15 (a) and 15 (b) are diagrams for explaining a modification of the first embodiment of the rotation detection operation in the rotation angle detection device according to the present invention. FIG. 15 (a) is a bottom view, and FIG. b) shows a side view. Reference numeral 14 in the figure denotes a magnetic convergence plate.

  In the configuration shown in FIG. 15, the first magnetoelectric conversion element 1 and the second magnetoelectric conversion element 2 are arranged in the vicinity of the circumference of a magnetic convergence plate 14 formed in a circle. The magnetic focusing plate 14 is made of a magnetic material, and can convert a horizontal magnetic field component into a vertical magnetic field component with respect to the magnetosensitive surfaces of the magnetoelectric conversion element 1 and the magnetoelectric conversion element 2. That is, in FIG. 15, a magnetic field parallel to the paper surface at the position of the magnetoelectric conversion element 1 and the magnetoelectric conversion element 2 can be converted into a magnetic field perpendicular to the paper surface by the magnetic converging plate 14. Therefore, it is suitable when a Hall element that detects only a magnetic field component perpendicular to the magnetosensitive surface of the magnetoelectric conversion element 1 and the magnetoelectric conversion element 2 is selected as the magnetoelectric conversion element. It is also possible to collect the surrounding magnetic flux and amplify the magnetic flux density applied to the magnetosensitive surface of the magnetoelectric transducer.

  In the above-described embodiment, the magnetoelectric conversion element 1 is driven into a sine wave by the sine wave driving unit 6 for the magnetoelectric conversion element 1, and the magnetoelectric conversion element 2 is driven by the cosine wave driving unit 7 for the magnetoelectric conversion element 2. The magnetoelectric transducers 1 and 2 are driven by the cosine wave as shown in FIG. 6, but the amplitude at this time may be any way.

  Further, instead of such a waveform, as shown in FIGS. 16, 17, and 18, a pseudo sine wave or a pseudo cosine wave imitating a sine wave or a cosine wave is used using a plurality of straight lines. Can also be implemented.

  FIG. 16 is a diagram illustrating a temporal change in the driving amount of the magnetoelectric conversion element in the present invention, and is a diagram illustrating an example of pseudo sine wave driving or cosine wave driving that can be substituted for FIG. In other words, the above-described sine wave and cosine wave are not realistic because the circuit scale and the like are large when actually manufactured on an IC. Therefore, pseudo sine wave driving or cosine driving with a pseudo sine wave or cosine wave is not possible. It is practical to use wave driving.

  FIG. 23 is a diagram illustrating an example of a method for creating the pseudo sine wave illustrated in FIGS. 16 and 24. When driving with a current amount as shown in FIG. 16, it can be easily implemented by converting the output of an example of the method shown in FIG. The current amounts of the constant current sources ICC1 to ICC4 are such that ICC1: ICC2 = 1: √2, ICC3: ICC4 = 1: 1: √2, ICC1 = ICC3, and an electrical angle of 0 to 45 °. The section closes only SW1 and SW2, the section from electrical angle 45 to 90 ° closes only SW1, the section from electrical angle 90 to 135 ° closes only SW3, and the electrical angle from 135 to 225 ° The section closes only SW3 and SW4, the section up to electrical angle 225-290 ° closes only SW3, the section up to electrical angle 290-315 ° closes only SW1, and the electrical angle up to 315-360 ° In the section, by closing only SW3 and SW4, a pseudo sine wave as shown in FIG. 16 can be created. Further, since the pseudo cosine wave is only 90 ° out of phase with respect to the sine wave, it can be created by shifting the timing of closing the SW in the same circuit.

  As described above, FIG. 23 is a diagram showing an example of a method for creating the pseudo sine wave shown in FIGS. 16 and 24, FIG. 16 is an example of current driving, and FIG. 24 is an example of voltage driving. Needless to say, any driving example can be applied to the present invention. When current driving is performed as shown in FIG. 16, it can be easily carried out by performing voltage-current conversion on the output of an example of the technique shown in FIG.

  FIG. 17 is a diagram for showing a temporal change in the drive amount of the magnetoelectric conversion element in the present invention, and is a diagram showing an example of another pseudo sine wave drive or cosine wave drive that can be substituted for FIG. The further pseudo sine wave or cosine wave is a pseudo sine wave or cosine wave with the staircase wave as a sine wave or cosine wave.

  In particular, the pseudo sine wave or cosine wave shown in FIG. 16 is preferable because it can be easily created in actual use. In the case of driving with an ideal sine / cosine wave as shown in FIG. 6, no theoretical rotation angle error occurs, but in the case of driving a pseudo sine / cosine wave as shown in FIG. An error occurs.

  FIG. 22 is a diagram showing a rotation angle error generation amount when driven by the pseudo sine wave shown in FIG. As shown in FIG. 22, the rotation angle error is about 0.5 °.

  Further, as a method for detecting the phase, in addition to the method of counting the time to the zero cross point using the above-described counter, the logic level is simply between the zero cross point and the logic low after the zero cross point. The level can also be a PWM output. Conversely, it is also possible to obtain a PWM output with the logic low level between the zero cross point and the logic high level after the zero cross point. Also, in detecting the zero cross point in this case, as described above, the sign of the addition result value obtained by the calculation unit 8 changes from positive to negative, or the point where the sign changes from negative to positive. Detection is possible even with either one.

  In the first embodiment, an example using a magnetic field, which is one of physical quantities, is shown, but the present invention can also be implemented using a physical quantity other than a magnetic field. In addition, although the example in which the driving of the magnetoelectric conversion element is performed in one cycle of 0.033 ms has been shown this time, this cycle can be implemented in any manner and may be set according to the required response speed.

  FIG. 18 is a diagram illustrating a temporal change in the driving amount of the magnetoelectric conversion element according to the present invention, and is a diagram illustrating an example of still another pseudo sine wave drive or cosine wave drive that can be substituted for FIG. . That is, a triangular wave is used. Even in this case, the above-described effects can be obtained.

  FIG. 19 is a diagram for explaining a position detection operation in the position detection apparatus according to the second embodiment of the present invention, in which reference numeral 15 denotes a position detection body (magnet), and 16 denotes a linear movement direction of the position detection body. , 17 are first magnetoelectric conversion elements, and 18 is a second magnetoelectric conversion element. The shape and moving direction of the detection target and the arrangement of the magnetoelectric conversion elements are different from those of the first embodiment described above. The other configuration is the same as that of the first embodiment, the driving state of each magnetoelectric conversion element is as shown in FIG. 6, and the block configuration diagram is the same as the configuration shown in FIG.

Next, the function of each part of the second embodiment will be described.
The first and second magnetoelectric transducers 17 and 18 are arranged immediately below the position detection body (magnet) 15 and are separated from each other by ¼ pole on the same plane. As shown in FIG. 6, one of the magnetoelectric transducers 17 and 18 is driven in a sine wave shape, and the other is driven in a cosine wave shape. Further, when the position detection body (magnet) 15 moves in any direction of the linear movement direction 16 of the position detection body 15, a magnetic field is applied to each of the magnetoelectric conversion elements 17 and 18 according to the position. The intensity is applied as shown in FIG.

  FIG. 20 is a diagram showing changes in the magnetic field strength applied to each of the magnetoelectric conversion elements accompanying the linear movement of the position detection body (magnet) shown in FIG. It can be seen that a magnetic field strength having a phase difference of 90 ° is applied between the magnetoelectric transducers 17 and 18 as the position detection body moves. The outputs of the magnetoelectric conversion elements 17 and 18 are proportional to the drive amount of the magnetoelectric conversion element and the magnetic field strength applied to the magnetoelectric conversion element.

  In other words, a magnetic field as shown in FIG. 20 is applied to each of the magnetoelectric conversion elements 17 and 18 in accordance with the movement of the position detection body. Here, the positional relationship as shown in FIG. 19 is defined as 0 μm, but any position may be 0 μm.

  In the configuration as described above, by performing the signal processing shown in the first embodiment, it is possible to linearly detect the distance that the N pole S pole moves. In addition, by counting the number of poles that have passed over the magnetoelectric conversion element based on the original position, position detection can be performed at a distance longer than the position detection between one N pole and S pole. .

  In the second embodiment described above, the magnetoelectric conversion element 17 is driven into a sine wave by the sine wave drive unit 6 for the magnetoelectric conversion element 17, and the magnetoelectric conversion element 18 is driven by the cosine wave drive unit 7 for the magnetoelectric conversion element 18. Is driven by the cosine wave, and the state is the same as that of driving the magnetoelectric transducers 1 and 2 as shown in FIG. 6, but the amplitude at this time may be any way. Further, instead of such a waveform, a pseudo sine wave or pseudo cosine imitating a sine wave or cosine wave using a plurality of inclined straight lines as shown in FIGS. It can also be implemented using waves. In particular, the waveform shown in FIG. 16 is preferable because it can be easily created in actual use.

  FIG. 23 is a diagram illustrating an example of a method for creating the pseudo sine wave illustrated in FIGS. 16 and 24. When driving with a current amount as shown in FIG. 16, it can be easily implemented by converting the output of an example of the method shown in FIG. The current amounts of the constant current sources ICC1 to ICC4 are such that ICC1: ICC2 = 1: √2, ICC3: ICC4 = 1: 1: √2, ICC1 = ICC3, and an electrical angle of 0 to 45 °. The section closes only SW1 and SW2, the section from electrical angle 45 to 90 ° closes only SW1, the section from electrical angle 90 to 135 ° closes only SW3, and the electrical angle from 135 to 225 ° The section closes only SW3 and SW4, the section up to electrical angle 225-290 ° closes only SW3, the section up to electrical angle 290-315 ° closes only SW1, and the electrical angle up to 315-360 ° In the section, by closing only SW3 and SW4, a pseudo sine wave as shown in FIG. 16 can be created. Further, since the pseudo cosine wave is only 90 ° out of phase with the sine wave, it can be created by shifting the timing of closing the SW in the same circuit.

  As described above, FIG. 23 is a diagram showing an example of a method for creating the pseudo sine wave shown in FIGS. 16 and 24, FIG. 16 is an example of current driving, and FIG. 24 is an example of voltage driving. Needless to say, any driving example can be applied to the present invention. When current driving is performed as shown in FIG. 16, it can be easily carried out by performing voltage-current conversion on the output of an example of the technique shown in FIG. When the driving frequency is high, the voltage driving is more preferable than the current driving in view of damage due to the excessive current density due to the skin effect.

  Further, as a method for detecting the phase, in addition to the method of counting the time to the zero cross point using the counter described above, the logic up to the zero cross point is simply set to the logic high level, and the logic after the zero cross point is set to the logic low level. The level can also be a PWM output. Conversely, it is also possible to obtain a PWM output with the logic low level between the zero cross point and the logic high level after the zero cross point. Also, in detecting the zero cross point in this case, as described above, the sign of the addition result value obtained by the calculation unit 8 changes from positive to negative, or the point where the sign changes from negative to positive. Detection is possible even with either one. Further, the dimension between the N poles and the S poles is not limited to that shown in FIG.

  FIG. 25 is a configuration diagram for explaining a gear tooth rotation detection operation in the rotation angle detection device according to the third embodiment of the present invention. In the figure, 24 is a gear tooth, 25 is a magnet, 26 is a rotation direction of the gear tooth, 27 is a first magnetoelectric conversion element, 28 is a second magnetoelectric conversion element, 29 is a third magnetoelectric conversion element, and 30 is a first The magnetoelectric conversion element 4 and d is the distance from the center of the gear teeth to the center, and indicates the pitch. The 1st magnetoelectric conversion element 27, the 2nd magnetoelectric conversion element 28, the 3rd magnetoelectric conversion element 29, and the 4th magnetoelectric conversion element 30 are arrange | positioned in the vicinity of the gear tooth | gear 24, and overlapped S pole and N pole. Each is provided on a fixed magnet 25 of the type. Each magnetoelectric conversion element is arranged with an interval of a pitch d / 4.

  FIG. 26 is a block diagram for explaining an embodiment of the gear tooth rotation angle detecting device according to the present invention, which is a modification of FIG. Specifically, subtraction operation units 43 and 44 are added to the preceding stage of the operation unit 8 in FIG. 1, and a third magnetoelectric conversion element 29 and a fourth magnetoelectric conversion element 30 are added. The subtraction operation units 43 and 44 output the output of the first magnetoelectric conversion element 27 and the output of the third magnetoelectric conversion element 29, and the output of the second magnetoelectric conversion element 28 and the fourth magnetoelectric conversion element 30. For subtracting the output of. 1 drives the first magnetoelectric conversion element 27 and the third magnetoelectric conversion element 29, and the cosine wave drive section 7 performs the second magnetoelectric conversion element 28 and the fourth magnetoelectric conversion. The device 30 is driven. FIG. 28 shows this driving state.

  The third embodiment is a rotation angle detecting device that detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with rotation of a gear tooth that is a rotation angle detector, and includes a gear tooth The first to fourth magnetoelectric transducers 27, 28, 29, 30 whose output changes in proportion to the change in the physical quantity with the rotation of the magnetic field and in proportion to the drive amount of the magnetoelectric transducer, and the first and third A sine wave drive unit 6 that applies a physical quantity that changes to a sine wave signal to the magnetoelectric conversion elements 27 and 29, and a cosine wave drive that applies a physical quantity that changes to a cosine wave signal to the second and fourth magnetoelectric conversion elements 28 and 30. A signal obtained by subtracting the output signal obtained by changing the drive amount of the unit 7 and the first and third magnetoelectric transducers 27 and 29 into a sine wave signal by the subtraction operation unit 43, Driving amount of fourth magnetoelectric conversion elements 28 and 30 A calculation unit 8 that calculates a signal obtained by subtracting the output signal obtained by changing to a cosine wave signal by the subtraction calculation unit 44, the output signal of the calculation unit 8, and the first and third magnetoelectrics Based on the phase detection unit 10 that detects the phase difference between the drive signals of the conversion elements 27 and 29 or the drive signals of the second and fourth magnetoelectric conversion elements 28 and 30, and the output signal from the phase detection unit 10 And an angle calculation unit 11 for calculating the rotation angle of the gear teeth.

  With such a configuration, when the gear tooth 24 is rotated from point A to point B in the rotation direction 26, a change in applied magnetic flux density of the magnetoelectric transducer with respect to the amount of rotation is obtained as shown in FIG. In the third embodiment, since the description is made using the 16-tooth gear, the angle between the teeth is 22.5 °. In the figure, symbol a is the first magnetoelectric transducer (solid line) 27, b is the second magnetoelectric transducer (broken line) 28, c is the third magnetoelectric transducer (dashed line) 29, and d is the first. This corresponds to four magnetoelectric conversion elements (two-dot chain lines) 30. That is, the plurality of magnetoelectric conversion elements 27, 28, 29, and 30 are arranged at intervals of a pitch d / 4.

  FIG. 27 shows that the magnetic field strength applied to each magnetoelectric conversion element changes in a sine / cosine wave shape as the gear rotates with an offset corresponding to the back bias magnet. In order to remove the influence of the offset on the final rotation angle output, as shown in FIGS. 25 and 26, four magnetoelectric transducers are loaded and a subtraction operation unit is loaded.

  FIG. 29 shows the output of each magnetoelectric conversion element when the rotation amount of the gear teeth is 0 °. As described in the first embodiment, the output is such that the output of the magnetoelectric conversion element is an output proportional to the drive amount and the applied magnetic field amount, and when the gear rotation amount is 0 ° in FIG. Looking at the amount of magnetic field applied to each magnetoelectric conversion element, the magnetoelectric conversion element 1 is about 90 mT, the magnetoelectric conversion element 2 is about 80 mT, the magnetoelectric conversion element 3 is about 80 mT, and the magnetoelectric conversion element 4 is about 70 mT. This is because the drive of the magnetoelectric transducer is as shown in FIG. Here, the magnetic sensitivity of each magnetoelectric conversion element is 1 mV / (mT · mA) (when the magnetoelectric conversion element is driven with a drive amount of 1 mA, a magnetic field intensity of 1 mT is applied to the magnetoelectric conversion element. 29, and the output from each magnetoelectric transducer is as shown in FIG.

  The outputs of the magnetoelectric conversion elements as shown in FIG. 29 are output from the first magnetoelectric conversion element 27 and the third magnetoelectric conversion element 29 by the subtraction operation units 43 and 44 in FIG. When the outputs of 28 and the fourth magnetoelectric transducer 30 are subtracted, the respective subtraction results are as shown in FIG. Similarly, FIG. 31 shows the output of each magnetoelectric conversion element when the amount of gear rotation is 0.9375 °, and FIG. 32 shows the first magnetoelectric conversion element 27 and the third magnetoelectric conversion element 29. As a result of subtracting the output of. The result of subtracting the outputs of the second magnetoelectric transducer 28 and the fourth magnetoelectric transducer 30 is shown. FIG. 33 shows the output of each magnetoelectric conversion element when the amount of rotation of the gear is 1.875 °, and FIG. 34 shows the outputs of the first magnetoelectric conversion element 27 and the third magnetoelectric conversion element 29. The result of subtraction and the result of subtracting the outputs of the second magnetoelectric conversion element 28 and the fourth magnetoelectric conversion element 30 are shown.

  The signals shown in FIGS. 30, 32, and 34 are input to the calculation unit 8 in FIG. 26, and the subsequent signal processing is performed in the same manner as in the first embodiment. With respect to the rotation amount of each gear, the output of the calculation unit 8 is as shown in FIG. 35. From this result, a waveform whose phase is changed in proportion to the rotation amount can be obtained as in the first embodiment. I understand. Therefore, the rotation angle between gear teeth can be identified.

  Also, by counting the number of teeth that have passed over the sensor due to the rotation of the gear, the above-mentioned output rotation angle + count value × 22.5 ° (gear tooth angle) is obtained. It is also possible to identify an angular position greater than this angle.

  In the third embodiment, the description has been given on the case where the number of gear teeth is 16, but the present invention can be implemented regardless of the number of teeth.

  In the third embodiment, the first magnetoelectric conversion element 27 and the third magnetoelectric conversion element 29 are driven like a sine wave, and the second magnetoelectric conversion element 28 and the fourth magnetoelectric conversion element 30 are cosine wave like. However, it can be carried out regardless of which one is driven in a sine wave-like or cosine wave-like manner. Further, as described in the first embodiment, this drive signal can be implemented as a pseudo sine wave or cosine wave.

In the third embodiment, four magnetoelectric conversion elements are used to remove the influence of the offset of the back bias magnet on the final rotation angle output. However, as in the first embodiment, only two elements are used. It can be implemented even if it is used. In this case, only the first magnetoelectric conversion element 27 and the second magnetoelectric conversion element 28 are used. At this time, when B ₀ is the offset magnetic field strength of the back bias magnet and the outputs of the magnetoelectric transducers are subtracted, a signal such as the following equation (3) is obtained.

  Looking at this result,

However, since all parameters in this term are known values determined by the user, the magnetic field intensity of the back bias magnet x magnetoelectric transducer drive The signal × magnetoelectric conversion element sensitivity signal is input to the subtraction operation units 43 and 44 in FIG. 26 and subtracted from the output signals of the first magnetoelectric conversion element 27 and the second magnetoelectric conversion element 28, thereby obtaining the back bias magnet component. It is possible to eliminate the influence of the offset of the rotation angle output (calculation result).

  FIG. 36 is a configuration diagram for explaining a gear tooth movement detection operation in the rotation angle detection device according to the fourth embodiment of the present invention. In the figure, 34 is a gear tooth, 35 is a magnet, 36 is a linear movement direction of the gear tooth, 37 is a first magnetoelectric conversion element, 38 is a second magnetoelectric conversion element, 39 is a third magnetoelectric conversion element, and 40 is 4 shows a fourth magnetoelectric transducer. The 1st magnetoelectric conversion element 37, the 2nd magnetoelectric conversion element 38, the 3rd magnetoelectric conversion element 39, and the 4th magnetoelectric conversion element 40 are arrange | positioned directly under the gear tooth 34, and overlapped S pole and N pole. Each is provided on a fixed magnet 35 of the type. Further, the magnetoelectric conversion elements are arranged with an interval of a pitch d / 4. In the fourth embodiment, the distance between teeth, that is, the pitch is assumed to be 360 mm.

  FIG. 26 is a block diagram for explaining an embodiment of the gear tooth movement detection device according to the present invention, which is a modification of FIG. Specifically, subtraction operation units 43 and 44 are added to the previous stage of the operation unit 8 in FIG. 1, and a third magnetoelectric conversion element 39 and a fourth magnetoelectric conversion element 40 are added. The subtraction operation units 43 and 44 output the output of the first magnetoelectric conversion element 37 and the output of the third magnetoelectric conversion element 39, and the output of the second magnetoelectric conversion element 38 and the fourth magnetoelectric conversion element 40. For subtracting the output of. 1 drives the first magnetoelectric conversion element 37 and the third magnetoelectric conversion element 39, and the cosine wave drive section 7 performs the second magnetoelectric conversion element 38 and the fourth magnetoelectric conversion. The device 40 is driven. FIG. 28 shows this driving state.

  The fourth embodiment is a position detection device that detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the movement of a gear tooth that is a position detection body, and includes a movement of a gear tooth. First to fourth magnetoelectric transducers 37, 38, 39, and 40 whose outputs change in proportion to the change in physical quantity accompanying them and in proportion to the drive amount of the magnetoelectric transducer, and the first and third magnetoelectric transducers. A sine wave drive unit 6 that applies a physical quantity that changes to a sine wave signal to the elements 37 and 39, and a cosine wave drive unit 7 that applies a physical quantity that changes to a cosine wave signal to the second and fourth magnetoelectric transducers 38 and 40. A signal obtained by subtracting the output signal obtained by changing the drive amount of the first and third magnetoelectric transducers 37 and 39 into a sinusoidal signal by the subtraction operation unit 43, and the second and fourth Drive amount of the magnetoelectric transducers 38 and 40 is a cosine wave A calculation unit 8 for calculating a signal obtained by subtracting an output signal obtained by changing the signal into a signal by the subtraction calculation unit 44; an output signal of the calculation unit 8; and first and third magnetoelectric transducers 37, 39, or the phase detector 10 for detecting the phase difference between the drive signals of the second and fourth magnetoelectric transducers 38, 40, and the gear teeth based on the output signal of the phase detector 10. A position calculation unit 12 for calculating a movement amount.

  With such a configuration, as the gear teeth 34 move from the point A in the linear motion direction 36 to the point B, a change in the applied magnetic flux density of the magnetoelectric transducer with respect to the amount of movement is obtained as shown in FIG. In the figure, symbol a is the first magnetoelectric transducer (solid line) 37, b is the second magnetoelectric transducer (dashed line) 38, c is the third magnetoelectric transducer (dashed line) 39, and d is the first. 4 corresponds to the magnetoelectric conversion element (two-dot chain line) 40. The plurality of magnetoelectric transducers 37, 38, 39, and 40 are arranged at intervals of a pitch d / 4.

  As can be seen from FIG. 37, with the offset of the back bias magnet, the magnetic field strength applied to each magnetoelectric conversion element changes in a sine / cosine wave shape as the gear moves. In order to remove the influence of the offset on the final position output, as shown in FIGS. 36 and 26, four magnetoelectric transducers are loaded and a subtraction operation unit is loaded.

  FIG. 38 shows the output of each magnetoelectric conversion element when the amount of movement of the gear is 0 mm. As described in the first embodiment, the output of the magnetoelectric conversion element is an output proportional to the drive amount and the applied magnetic field amount, and each output is obtained when the gear movement amount is 0 mm in FIG. Looking at the amount of magnetic field applied to the magnetoelectric conversion element, the magnetoelectric conversion element 1 is about 90 mT, the magnetoelectric conversion element 2 is about 80 mT, the magnetoelectric conversion element 3 is about 80 mT, and the magnetoelectric conversion element 4 is about 70 mT. This is because the driving of the magnetoelectric transducer is as shown in FIG. Here, the magnetic sensitivity of each magnetoelectric conversion element is 1 mV / (mT · mA) (when the magnetoelectric conversion element is driven with a drive amount of 1 mA, a magnetic field intensity of 1 mT is applied to the magnetoelectric conversion element. The output from each magnetoelectric conversion element is as shown in FIG.

  The subtraction operation units 43 and 44 in FIG. 26 subtract the outputs of the first magnetoelectric conversion element 37 and the third magnetoelectric conversion element 39 from the output of the magnetoelectric conversion element as shown in FIG. When the outputs of the element 38 and the fourth magnetoelectric transducer 40 are subtracted, the respective subtraction results are as shown in FIG. Similarly, FIG. 40 shows the output of each magnetoelectric conversion element when the amount of movement of the gear is 15 mm, and FIG. 41 subtracts the outputs of the first magnetoelectric conversion element and the third magnetoelectric conversion element. The result and the result of subtracting the outputs of the second magnetoelectric conversion element 28 and the fourth magnetoelectric conversion element 40 are shown. FIG. 42 shows the output of each magnetoelectric conversion element when the amount of gear movement is 30 mm, and FIG. 43 shows the result of subtracting the outputs of the first magnetoelectric conversion element 37 and the third magnetoelectric conversion element 39. Also, the result of subtracting the outputs of the second magnetoelectric conversion element 38 and the fourth magnetoelectric conversion element 40 is shown.

  The signals shown in FIG. 39, FIG. 41, and FIG. 43 are input to the calculation unit 8 in FIG. With respect to the movement amount of each gear, the output of the calculation unit 8 is as shown in FIG. 44. Looking at this result, a waveform whose phase is changed in proportion to the movement amount is obtained as in the first embodiment. I understand that Therefore, the movement amount between the gear teeth can be identified.

  In addition, by counting the number of teeth that have passed over the sensor due to the movement of the gear, the above-mentioned output movement amount + count value × 360 mm (distance between gear teeth) is greater than the movement amount between the gear teeth. It is also possible to identify the amount of movement.

  In the fourth embodiment, the pitch between the gear teeth has been described as being 360 mm. However, this pitch can be implemented regardless of the pitch.

  In the fourth embodiment, the first magnetoelectric conversion element 37 and the third magnetoelectric conversion element 39 are driven in a sine wave manner, and the second magnetoelectric conversion element 38 and the fourth magnetoelectric conversion element 40 are made in a cosine wave manner. However, it can be carried out regardless of which one is driven in a sine wave-like or cosine wave-like manner. Further, as described in the first embodiment, this drive signal can be implemented as a pseudo sine wave or cosine wave.

In the fourth embodiment, four magnetoelectric conversion elements are used to remove the influence of the offset of the back bias magnet on the final position output. However, only two elements are used as in the first embodiment. However, it can be implemented. In this case, only the first magnetoelectric conversion element 37 and the second magnetoelectric conversion element 38 are used. At this time, if B ₀ is the offset magnetic field strength of the back bias magnet, θ is the amount of movement of the gear teeth, and the mutual outputs of the magnetoelectric transducers are subtracted, a signal of the following equation (4) is obtained.

  Looking at this result,

However, since all parameters in this term are known values determined by the user, the magnetic field intensity of the back bias magnet x magnetoelectric transducer drive The signal × magnetoelectric conversion element sensitivity signal is input to the subtraction operation units 43 and 44 in FIG. 26, and is subtracted from the output signals of the first magnetoelectric conversion element 37 and the second magnetoelectric conversion element 38. It is possible to eliminate the influence of the offset on the position output (calculation result).

  Since the present invention can be implemented with a simple configuration and can obtain angle or position information that does not depend on temperature without using complicated calculations, the rotation angle detection device, the position detection sensor, and the rotation angle can be obtained. Since a detection method and a position detection method can be provided, it can be used for, for example, a rotation switch, a potentiometer, an input device application, a linear motion position detection, and the like.

1 First physical quantity detection element (magnetoelectric conversion element)
2 Second physical quantity detection element (magnetoelectric conversion element)
3 Rotating angle detector (magnet) having N and S poles
4 Rotating shaft 5 of rotation angle detection body 6 Rotation direction 6 Sine wave drive unit 7 Cosine wave drive unit 8 Calculation unit 9 (91, 92) Zero cross point detection unit and counter 10 Counter value output unit (phase detection unit)
DESCRIPTION OF SYMBOLS 11 Angle calculation part 12 Position calculation part 14 Magnetic convergence plate 15 Position detection body (magnet)
16 Linear motion direction of the position detection body 17, 27, 37 First magnetoelectric conversion elements 18, 28, 38 Second magnetoelectric conversion elements 24, 34 Gear teeth 25, 35 Magnet 26 Rotation direction of gear teeth 29, 39 3 Magnetoelectric conversion elements 30, 40 Fourth magnetoelectric conversion element 36 Gear teeth linear movement direction 43, 44 Subtraction calculation unit d Distance (pitch) from center to center of gear teeth
A Auxiliary line for indicating magnetic field strength applied to each magnetoelectric conversion element when the angular position of the detected object is 0 ° B Applied to each magnetoelectric conversion element when the angular position of the detected object is 15 ° Auxiliary line C for indicating magnetic field strength An auxiliary line for indicating the magnetic field strength applied to each magnetoelectric conversion element when the detected object is at an angular position of 30 °.

Claims (60)

In a rotation angle detection device that detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the rotation of a rotation angle detector,
At least two or more physical quantity detection elements whose output changes in proportion to the change in the physical quantity accompanying rotation of the rotation angle detector and in proportion to the drive quantity of the physical quantity detection element;
One drive unit that applies a physical quantity that changes to a sinusoidal signal to the one physical quantity detection element;
The other drive unit for applying a physical quantity that changes to a cosine wave signal to the other physical quantity detection element;
An output signal obtained by changing the drive amount of the one physical quantity detection element into a sine wave signal and an output signal obtained by changing the drive amount of the other physical quantity detection element into a cosine wave signal are calculated. An arithmetic unit;
A phase detection unit that detects a phase difference between the output signal of the calculation unit and the drive signal of the one physical quantity detection element or the drive signal of the other physical quantity detection element;
A rotation angle detection device comprising: an angle calculation unit that calculates a rotation angle of the rotation angle detector based on an output signal from the phase detection unit.   The rotation angle detection device according to claim 1, wherein the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.   The rotation angle detection device according to claim 1 or 2, further comprising a zero cross point detection unit for detecting a phase difference in the phase detection unit by zero cross point detection at a subsequent stage of the calculation unit. .   The rotation angle detection device according to claim 1, wherein the calculation unit includes an adder or a subtracter.   The rotation angle detection device according to claim 4, wherein the phase detection unit detects a phase difference between the addition value or the subtraction value calculated by the calculation unit and the drive signal.   6. The rotation angle detection device according to claim 1, wherein the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element.   The magnetoelectric conversion elements are provided adjacent to each other along with other arithmetic circuits on a Si substrate by circuit integration technology, and the at least two or more magnetoelectric conversion elements have equal output temperature characteristics. The rotation angle detection device according to claim 6.   The rotation angle detection device according to claim 6 or 7, wherein the magnetoelectric conversion element is arranged in the vicinity of the end of the lower surface of the magnetic converging plate. In a position detection device that detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the movement of a position detection body, using a physical quantity detection element,
At least two or more physical quantity detection elements whose output changes in proportion to the change in the physical quantity accompanying the movement of the position detection body and in proportion to the drive quantity of the physical quantity detection element;
One drive unit that applies a physical quantity that changes to a sinusoidal signal to the one physical quantity detection element;
The other drive unit for applying a physical quantity that changes to a cosine wave signal to the other physical quantity detection element;
An output signal obtained by changing the drive amount of the one physical quantity detection element into a sine wave signal and an output signal obtained by changing the drive amount of the other physical quantity detection element into a cosine wave signal are calculated. An arithmetic unit;
A phase detection unit that detects a phase difference between the output signal of the calculation unit and the drive signal of the one physical quantity detection element or the drive signal of the other physical quantity detection element;
A position calculation unit comprising: a position calculation unit that calculates a movement amount of the position detection object based on an output signal of the phase detection unit.   The position detecting device according to claim 9, wherein the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.   The position detection device according to claim 9 or 10, wherein a zero cross point detection unit for performing phase difference detection in the phase detection unit by zero cross point detection is provided at a subsequent stage of the calculation unit.   The position detection device according to claim 9, wherein the calculation unit includes an adder or a subtracter.   The position detection device according to claim 12, wherein the phase detection unit detects a phase difference between the addition value or the subtraction value calculated by the calculation unit and the drive signal.   The position detection device according to claim 9, wherein the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element.   The magnetoelectric conversion elements are provided adjacent to each other along with other arithmetic circuits on a Si substrate by circuit integration technology, and the at least two or more magnetoelectric conversion elements have equal output temperature characteristics. The position detection device according to claim 14.   The position detection device according to claim 14, wherein the magnetoelectric conversion element is disposed in the vicinity of an end of a lower surface of the magnetic convergence plate. In a rotation angle detection device that detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the rotation of a gear tooth that is a rotation angle detector,
First to fourth physical quantity detection elements whose output changes in proportion to a change in the physical quantity accompanying the rotation of the gear teeth and in proportion to a drive quantity of the physical quantity detection element;
One drive unit that applies a physical quantity that changes to a sinusoidal signal to the first and third physical quantity detection elements;
The other drive unit for applying a physical quantity that changes to a cosine wave signal to the second and fourth physical quantity detection elements;
A signal obtained by subtracting an output signal obtained by changing the drive amount of the first and third physical quantity detection elements into a sine wave signal, and the drive amount of the second and fourth physical quantity detection elements are obtained. An arithmetic unit that calculates a signal obtained by subtracting an output signal obtained by changing to a cosine wave signal;
A phase detection unit that detects a phase difference between the output signal of the calculation unit and the drive signals of the first and third physical quantity detection elements or the drive signals of the second and fourth physical quantity detection elements;
An angle calculation unit that calculates the rotation angle of the gear teeth based on an output signal from the phase detection unit.   The rotation angle detecting device according to claim 17, wherein the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.   The rotation angle detection device according to claim 17 or 18, wherein a zero cross point detection unit for detecting a phase difference in the phase detection unit by zero cross point detection is provided at a subsequent stage of the calculation unit. .   The rotation angle detection device according to claim 17, 18 or 19, further comprising a subtracter in front of the calculation unit.   The rotation angle detection apparatus according to claim 20, wherein the phase detection unit detects a phase difference between the subtraction value or the addition value calculated by the calculation unit and the drive signal.   The rotation angle detection device according to any one of claims 17 to 21, wherein the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element.   The magnetoelectric conversion elements are provided adjacent to each other together with other arithmetic circuits on a Si substrate by circuit integration technology, and the first to fourth magnetoelectric conversion elements have equal output temperature characteristics. The rotation angle detection device according to claim 22.   The rotation angle detection device according to claim 22 or 23, wherein the magnetoelectric conversion element is arranged immediately below the gear teeth.   The rotation angle detection device according to any one of claims 17 to 24, wherein the plurality of magnetoelectric transducers are arranged at an interval of a pitch d / 4 of the gear teeth. In a position detection device that detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the movement of a gear tooth that is a position detection body,
First to fourth physical quantity detection elements whose output is proportional to the change in the physical quantity accompanying the movement of the gear teeth, and whose output changes in proportion to the drive quantity of the physical quantity detection element;
One drive unit that applies a physical quantity that changes to a sinusoidal signal to the first and third physical quantity detection elements;
The other drive unit for applying a physical quantity that changes to a cosine wave signal to the second and fourth physical quantity detection elements;
A signal obtained by subtracting an output signal obtained by changing the drive amount of the first and third physical quantity detection elements into a sine wave signal, and the drive amount of the second and fourth physical quantity detection elements are obtained. An arithmetic unit that calculates a signal obtained by subtracting an output signal obtained by changing to a cosine wave signal;
A phase detection unit that detects a phase difference between the output signal of the calculation unit and the drive signals of the first and third physical quantity detection elements or the drive signals of the second and fourth physical quantity detection elements;
A position calculation unit comprising: a position calculation unit that calculates a movement amount of the gear teeth based on an output signal of the phase detection unit.   27. The position detecting device according to claim 26, wherein the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.   28. The position detection device according to claim 26 or 27, further comprising a zero cross point detection unit for detecting a phase difference in the phase detection unit by zero cross point detection at a subsequent stage of the calculation unit.   29. The position detection device according to claim 26, 27 or 28, further comprising a subtracter in front of the arithmetic unit.   30. The position detection device according to claim 29, wherein the phase detection unit detects a phase difference between the subtraction value or the addition value calculated by the calculation unit and the drive signal.   31. The position detection device according to claim 26, wherein the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element.   The magnetoelectric conversion elements are provided adjacent to each other together with other arithmetic circuits on a Si substrate by circuit integration technology, and the first to fourth magnetoelectric conversion elements have equal output temperature characteristics. The position detection device according to claim 31.   The position detection device according to claim 31 or 32, wherein the magnetoelectric conversion element is arranged immediately below the gear teeth.   The rotation angle detection device according to any one of claims 26 to 33, wherein the plurality of magnetoelectric transducers are arranged at intervals of a pitch d / 4 of the gear teeth. In a rotation angle detection method in which a physical quantity detection element detects a change in a physical quantity that changes into a sine wave signal or a cosine wave signal as the rotation angle detector is rotated.
Using at least two or more physical quantity detection elements whose output changes in proportion to the change in the physical quantity with the rotation of the rotation angle detector and in proportion to the drive quantity of the physical quantity detection element,
Applying a physical quantity that changes to a sinusoidal signal to the one physical quantity detection element;
Applying a physical quantity that changes to a cosine wave signal to the other physical quantity detection element;
An output signal obtained by changing the drive amount of the one physical quantity detection element into a sine wave signal and an output signal obtained by changing the drive amount of the other physical quantity detection element into a cosine wave signal are calculated. Steps,
Detecting a phase difference between the output signal of the arithmetic unit and the drive signal of the one physical quantity detection element or the drive signal of the other physical quantity detection element;
And calculating a rotation angle of the rotation angle detector based on an output signal from the phase detection unit.   The rotation angle detection method according to claim 35, wherein the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.   37. The rotation according to claim 35 or 36, further comprising a zero cross point detecting step for performing phase difference detection by zero cross point detection in the step of detecting the phase difference after the step of calculating. Angle detection method.   38. The rotation angle detection method according to claim 35, 36 or 37, wherein the calculating step includes a step of adding or subtracting.   The rotation angle detection method according to claim 38, wherein the step of detecting the phase difference detects a phase difference between the addition value or the subtraction value calculated in the step of calculating and the drive signal.   The rotation angle detection method according to any one of claims 35 to 39, wherein the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element. In a position detection method for detecting a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the movement of a position detection body, using a physical quantity detection element,
Using at least two or more physical quantity detection elements whose output changes in proportion to the change in the physical quantity accompanying the movement of the position detection body and in proportion to the drive quantity of the physical quantity detection element,
Applying a physical quantity that changes to a sinusoidal signal to the one physical quantity detection element;
Applying a physical quantity that changes to a cosine wave signal to the other physical quantity detection element;
An output signal obtained by changing the driving amount of the one physical quantity detection element into a sinusoidal signal;
Calculating an output signal obtained by changing the driving amount of the other physical quantity detection element into a cosine wave signal;
Detecting a phase difference between the output signal of the arithmetic unit and the drive signal of the one physical quantity detection element or the drive signal of the other physical quantity detection element;
Calculating a position of the position detection object based on an output signal from the phase detection unit.   The position detection method according to claim 41, wherein the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.   The position according to claim 41 or 42, further comprising a zero cross point detection step for performing phase difference detection by zero cross point detection in the step of detecting the phase difference after the step of calculating. Detection method.   44. The position detecting method according to claim 41, 42 or 43, wherein the calculating step includes a step of adding or subtracting.   45. The position detection method according to claim 44, wherein the step of detecting the phase difference detects a phase difference between the addition value or subtraction value calculated in the step of calculating and the drive signal.   46. The position detection method according to claim 41, wherein the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element. In a rotation angle detection method in which a change in a physical quantity that changes to a sine wave signal or a cosine wave signal with the rotation of a gear tooth that is a rotation angle detector is detected by a physical quantity detection element,
Using the first to fourth physical quantity detection elements whose output changes in proportion to the change in the physical quantity accompanying the rotation of the gear teeth and in proportion to the drive quantity of the physical quantity detection element,
Applying a physical quantity that changes to a sinusoidal signal to the first and third physical quantity detection elements;
Applying a physical quantity that changes to a cosine wave signal to the second and fourth physical quantity detection elements;
A signal obtained by subtracting an output signal obtained by changing the drive amount of the first and third physical quantity detection elements into a sine wave signal, and the drive amount of the second and fourth physical quantity detection elements are obtained. Calculating a signal obtained by subtracting an output signal obtained by changing to a cosine wave signal;
Detecting a phase difference between the output signal of the calculation unit and the drive signals of the first and third physical quantity detection elements or the drive signals of the second and fourth physical quantity detection elements;
And calculating a rotation angle of the gear teeth based on an output signal from the phase detection unit.   The rotation angle detection method according to claim 47, wherein the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.   49. The rotation according to claim 47 or 48, further comprising a zero cross point detecting step for performing phase difference detection by zero cross point detection in the step of detecting the phase difference after the step of calculating. Angle detection method.   50. The rotation angle detection method according to claim 47, 48 or 49, further comprising a step of subtracting before the step of calculating.   The rotation angle detection method according to claim 50, wherein the step of detecting the phase difference detects a phase difference between the subtraction value or the addition value calculated in the step of calculating and the drive signal.   52. The rotation angle detection method according to claim 47, wherein the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element.   53. The rotation angle detection method according to claim 47, wherein the plurality of magnetoelectric transducers are arranged at intervals of a pitch d / 4 of the gear teeth. In a position detection method in which a physical quantity detection element detects a change in a physical quantity that changes to a sine wave signal or a cosine wave signal along with the movement of a gear tooth that is a position detection body,
Using the first to fourth physical quantity detection elements whose output changes in proportion to the change in the physical quantity accompanying the movement of the gear teeth and in proportion to the drive quantity of the physical quantity detection element,
Applying a physical quantity that changes to a sinusoidal signal to the first and third physical quantity detection elements;
Applying a physical quantity that changes to a cosine wave signal to the second and fourth physical quantity detection elements;
A signal obtained by subtracting an output signal obtained by changing the drive amount of the first and third physical quantity detection elements into a sine wave signal, and the drive amount of the second and fourth physical quantity detection elements are obtained. Calculating a signal obtained by subtracting an output signal obtained by changing to a cosine wave signal;
Detecting a phase difference between the output signal of the calculation unit and the drive signals of the first and third physical quantity detection elements or the drive signals of the second and fourth physical quantity detection elements;
Calculating a position of the gear teeth based on an output signal from the phase detection unit.   55. The position detection method according to claim 54, wherein the sine wave signal includes a pseudo sine wave signal, and the cosine wave signal includes a pseudo cosine wave signal.   The position according to claim 54 or 55, further comprising a zero cross point detection step for performing phase difference detection by zero cross point detection in the step of detecting the phase difference after the step of calculating. Detection method.   57. The position detection method according to claim 54, 55 or 56, further comprising a step of subtracting before the step of calculating.   58. The position detection method according to claim 57, wherein the step of detecting the phase difference detects a phase difference between the subtraction value or the addition value calculated in the calculation step and the drive signal.   59. The position detection method according to claim 54, wherein the physical quantity is a magnetic field intensity, and the physical quantity detection element is a magnetoelectric conversion element.   The rotation angle detection method according to any one of claims 54 to 59, wherein the plurality of magnetoelectric transducers are arranged at intervals of a pitch d / 4 of the gear teeth.

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