JP2012052960A - Rotation angle detecting device, and assembling method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the detection accuracy of a rotation angle of a suction valve 11.SOLUTION: In a step for manufacturing an electronic throttle 1, a signal processing circuit 22a calculates correction value functions α, β and a gain correction value G for correcting a detection signal of a magnetic detection element 31, and stores the calculated correction value functions α, β, and the gain correction value G in a memory. When receiving a command from an electronic control device 40, the signal processing circuit 22a corrects the detection signal of the magnetic detection element 31 by using the correction value functions α, β, and the gain correction value G which are stored in the memory, and calculates a detection signal after correction to output to the electronic control device 40.

Description

  The present invention relates to a rotation angle detecting device and an assembling method thereof.

  2. Description of the Related Art Conventionally, in an electronic throttle for engine control, a throttle body having an intake passage, an air amount adjusting valve for adjusting the opening of the intake passage by rotation, and a rotation angle of the air amount adjusting valve is detected as the opening of the intake passage. Some sensor assemblies include a rotation angle sensor and a sensor assembly having a temperature sensor for detecting the air temperature in the intake passage (see, for example, Patent Document 1).

  In recent years, there has been a demand for higher accuracy in detecting the rotation angle of the air amount control valve. There are contact type (sliding resistance type) and non-contact type (magnetic detection method, electromagnetic induction method), etc. as the rotation angle sensor that detects the rotation angle of the air amount control valve. Among them, the magnetic detection method is mainly used. The rotation angle sensor of the magnetic detection system is mainly composed of a magnetic detection IC and a magnet.

  In addition to the accuracy of the magnetic detection IC itself, the positional relationship between the magnet and the magnetic detection IC is important for increasing the detection accuracy of the magnetic detection system. For this reason, the sensor assembly of Patent Document 1 is provided with a protrusion having a storage chamber for storing the temperature sensor, and the rotation angle sensor is positioned with respect to the magnet by inserting the protrusion into the hole of the throttle body.

JP 2007-239560 A

  However, in Patent Document 1, when the protrusion of the sensor assembly is inserted into the hole of the throttle body, a gap is formed between the protrusion and the inner wall of the hole of the throttle body, and the sensor assembly is screwed to the throttle body. There is a possibility that a subtle position error (several tens to several hundreds of um) may occur when stopping. Here, although a large position error (several mm) can be adjusted, it is difficult to reduce the assembly error enough to cope with the recent high accuracy. For this reason, there may be a case where the detection accuracy of the rotation angle by the magnetic detection IC is lowered due to a delicate position error.

  The present invention has been made in view of the above points, and it is an object of the present invention to provide a rotation angle detection device and an assembling method for improving the rotation angle detection accuracy.

In order to achieve the above object, according to the first aspect of the present invention, there is provided a main element that outputs a detection signal indicating a rotation angle of the rotating body based on a magnetic field formed by a magnet rotating with the rotation of the rotating body. The main element is a rotation angle detection device assembled so that the center position thereof coincides with the rotation axis of the magnet,
Around the main element, a plurality of auxiliary elements that respectively output detection signals based on the magnetic field formed by the magnet are arranged,
Based on detection signals output from the plurality of complementary elements, a deviation amount between the center position of the main element and the rotation axis of the magnet is obtained, and a detection signal output from the main element is calculated based on the deviation amount. It comprises signal processing means for correcting.

  According to the present invention, the amount of deviation between the center position of the rotation angle detection magnetic detection element and the rotation axis of the magnet is obtained, thereby correcting the detection signal output from the rotation angle detection magnetic detection element. It is possible to reduce the influence due to the assembly error of the magnetic detection element for detecting the rotation angle and improve the detection accuracy of the rotation angle.

  Specifically, in the invention according to claim 2, in the rotation angle detection device according to claim 1, the main element is arranged at the center of gravity in a polygon whose apexes are the positions of the plurality of complementary elements. May be. A vertex is a point where two sides intersect to form an angle in a polygon.

According to a third aspect of the present invention, in the rotation angle detecting device according to the first or second aspect, the rotation axis of the magnet is a Z axis, and an axis orthogonal to and perpendicular to each other is an X axis and a Y axis. In the coordinate system, the plurality of complementary elements are arranged at positions symmetrical with respect to the X coordinate position of the main element in the X axis direction, and are symmetric with respect to the Y coordinate position of the main element in the Y axis direction. Is located at
The signal processing means is configured such that when the angle formed between the N-pole and S-pole of the magnet and the X-axis is 0 degree, a deviation in the X-axis direction between the center position of the main element and the rotation axis of the magnet. An amount is obtained, and when the angle is 90 degrees, a deviation amount in the Y-axis direction between the center position of the main element and the rotation axis of the magnet is obtained.

  In this way, it is possible to determine the amount of deviation in the X-axis direction and the Y-axis direction between the center position of the magnetic sensor for detecting the rotation angle and the rotation axis of the magnet, and correct it.

  According to a fourth aspect of the present invention, in the rotation angle detection device according to the third aspect, the signal processing means is configured to detect a detection signal output from the main element when the angle changes from 0 degrees to 90 degrees. A deviation amount in the Z-axis direction between the center position of the main element and the rotation axis of the magnet is obtained based on a maximum amplitude value.

  In this way, in addition to the shift amount in the X-axis direction and the Y-axis direction between the center position of the magnetic detection element for detecting the rotation angle and the rotation axis of the magnet, the shift amount in the Z-axis direction is obtained and corrected. Can do.

Specifically, as in the invention described in claim 5, the magnet may be arranged such that a direction connecting the north pole and the south pole is orthogonal to the axial direction of the rotating shaft. As in the sixth aspect of the invention, the main element and the plurality of auxiliary elements may be mounted on a substrate. According to a seventh aspect of the present invention, the substrate may be formed in a square shape, and four complementary elements as the plurality of complementary elements may be distributed and arranged at four corners of the substrate.
As in the invention described in claim 8, a signal processing circuit constituting the signal processing means may be mounted on the substrate. As in the ninth aspect of the invention, the signal processing circuit may be arranged on one surface of the substrate on which the main element and the plurality of auxiliary elements are mounted.

In a tenth aspect of the present invention, a main element that outputs a detection signal indicating a rotation angle of the rotating body based on a magnetic field formed by the magnet to a body having a magnet that rotates as the rotating body rotates. An assembly method of a rotation angle detection device that is assembled so that the center position of the main element coincides with the rotation axis of the magnet,
In the rotation angle detection device, a plurality of auxiliary elements that output detection signals based on the magnetic field formed by the magnet are arranged around the main element,
An adjustment step of adjusting the assembly position of the rotation angle detection device with respect to the body;
In this adjustment step, based on detection signals output from the plurality of complementary elements, a deviation amount between the center position of the main element and the rotation axis of the magnet is obtained, and this deviation amount is used to adjust the assembly position. It is characterized by being output to.

  According to the present invention, the amount of deviation between the center position of the magnetic sensor for detecting the rotation angle and the rotation axis of the magnet is obtained, and this amount of deviation is output for adjustment of the assembly position. The assembly position of the rotation angle detection device can be adjusted.

  It should be noted that the inventions described in claims 2 to 9 can be similarly applied to the invention described in claim 10.

It is a figure which shows the cross-sectional structure of the electronic throttle in 1st Embodiment of this invention. It is AA sectional drawing in FIG. It is a top view of the magnetic detection IC of FIG. It is a figure which shows the electrical structure of the electronic throttle of FIG. It is a figure which shows the angle of the magnet with respect to the sensor assembly of FIG. It is a flowchart which shows the order of the manufacturing process of the electronic throttle of FIG. It is a flowchart which shows the signal processing of the signal processing circuit of FIG. It is the figure which showed typically the arrangement | positioning relationship between the magnetic detection element and magnet in 1st Embodiment. It is the figure which showed typically the arrangement | positioning relationship between the magnetic detection element and magnet in 1st Embodiment. It is a figure which shows an electrical structure in 2nd Embodiment of this invention. It is a flowchart which shows the signal processing of the magnetic detection IC output calculating apparatus in 2nd Embodiment. It is a figure which shows the cross-sectional structure of the electronic throttle which is the 1st modification of this invention. It is a figure which shows the magnetic detection unit which is the 1st modification of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are given the same reference numerals in the drawings in order to simplify the description.

(First embodiment)
1 and 2 show a first embodiment of an electronic throttle 1 according to the present invention. 1 is a cross-sectional view of the electronic throttle 1, and FIG. 2 is a cross-sectional view taken along line AA in FIG.

  The electronic throttle 1 controls the amount of air taken into the internal combustion engine, and includes a sensor assembly 2 and a throttle body assembly 3 as shown in FIGS.

  The throttle body assembly 3 includes a throttle body 10, an intake valve (rotary body) 11, gears 13, 13 a, 13 e, a protective case 14, a support member 15, an electric motor 16, and a magnet 17.

  As shown in FIG. 1, the throttle body 10 includes an intake passage 10A and bearings 10a and 10b. The intake passage 10A is a passage that guides air to the internal combustion engine.

  The bearing 10a is formed so as to protrude upward from the throttle body 10 into the recess 10d. The recess 10d is formed in an annular shape centering on the bearing 10a, and is used for positioning the throttle body 10 with respect to the sensor assembly 2 as will be described later. The bearing 10b is formed so as to protrude downward from the throttle body 10 in the figure.

  The intake valve 11 is an air amount adjusting valve configured by attaching rotary shafts 11a and 11b to a valve body 11c. The rotary shafts 11a and 11b are arranged so that their axial directions coincide with each other. The intake valve 11 adjusts the amount of air taken into the internal combustion engine by adjusting the opening in the intake passage 10A by rotation about the rotation shafts 11a and 11b. The rotating shaft 11a is rotatably supported by a bearing 10a of the throttle body 10. The rotating shaft 11b is rotatably supported by a bearing 10b of the throttle body 10.

  The support member 15 is disposed on one axial side (the upper side in the drawing) of the rotating shaft 11a, and is formed in a cylindrical shape having a circular opening 15a. The support member 15 is fastened with a screw 15a by a rotating shaft 11a. The magnet 17 constitutes a disk-shaped permanent magnet and is fitted into the opening 15 a of the support member 15. The magnet 17 is arranged so that the center thereof coincides with the axis of the rotary shaft 11a and is orthogonal to the axial direction of the rotary shaft 11a. Of the two semicircular parts that divide the magnet 17 into two, one is an N pole and the other is an S pole. As a result, the direction connecting the N pole and the S pole in the magnet 17 is orthogonal to the axial direction of the rotating shaft 11a. As will be described later, the magnet 17 is used for detecting the rotation angle of the intake valve 11 by rotating with the rotation of the rotating shaft 11a.

  The gear 13 constitutes a spur gear and is disposed on the lower side of the throttle body 10 in the figure. The gear 13 is supported on one axial end side (the lower side in the drawing) of the rotary shaft 11b. As shown in FIG. 2, the gears 13 a and 13 e constitute a spur gear and are arranged on the lower side of the throttle body 10 in the figure. The gear 13a is rotatably supported by the shaft 13b. The shaft 13b is disposed on the lower side of the throttle body 10 in the figure. The gear 13 e is supported on the output shaft 13 d of the electric motor 16. The electric motor 16 is accommodated in the recess 10 c of the throttle body 10. The electric motor 16 is a shaft rotation motor that outputs the rotational force to the intake valve 11 via gears 13e, 13a, and 13. The protective case 14 is formed so as to cover the electric motor 16 and the gears 13, 13a, and 13e from the lower side in the figure. The protective case 14 is fastened to the throttle body 10 with screws 12a and 12b.

  The sensor assembly 2 constitutes a rotation angle detection device, and is composed of a sensor case 20, a substrate 21, and a magnetic detection IC 22, as shown in FIG.

  The sensor case 20 is disposed on one side (the upper side in the drawing) of the rotary shaft 11a with respect to the throttle body 10.

  A convex portion 20a is provided on the other side (lower side in the drawing) of the rotating shaft 11a in the sensor case 20. The convex portion 20a is formed in an annular shape centered on the rotation shaft 11a. The convex portion 20 a is fitted to the outer peripheral side of the support member 15 in the concave portion 10 d of the throttle body 10. The convex portion 20 a determines the position of the sensor assembly 2 with respect to the throttle body 10. The sensor case 20 is provided with a recess 23 that opens to one side (the upper side in the drawing) of the rotating shaft 11a. A recess 24 is provided in the sensor case 20 on the other axial side (the lower side in the drawing) of the rotating shaft 11a. The support member 15 and the magnet 17 enter the recess 24. For this reason, the magnet 17 faces the ceiling surface 24 a of the recess 24.

  The board | substrate 21 is a printed circuit board, Comprising: It arrange | positions in the recessed part 23 of the sensor case 20, and is arrange | positioned so that it may orthogonally cross with respect to the axial direction of rotating shaft 11a, 11b. The substrate 21 is fastened to the bottom portion in the opening 23 by screws 21a and 21b. On the substrate 21, in addition to the magnetic detection IC 22, a temperature sensor (not shown) for detecting the air temperature in the intake passage 10A is mounted. The magnetic detection IC 22 is formed in a plate shape and is disposed on the substrate 21. The magnetic detection IC 22 is connected to the substrate 21 by the lead 22b.

  FIG. 3 is a top view of the magnetic detection IC 22 in FIG. 1 viewed from above.

  The magnetic detection IC 22 includes a substrate 30 and magnetic detection elements 31, 32a, 32b, 32c, and 32d. The substrate 30 is a silicon substrate formed in a square shape. The substrate 30 is disposed with its upper surface directed toward one axial side of the rotating shaft 11a (upper side in FIG. 1). The substrate 30 is arranged such that the center of the upper surface thereof overlaps with the axial direction of the rotary shaft 11a.

  The magnetic detection element 31 is mounted at the center of the upper surface of the substrate 30. That is, the magnetic detection element 31 is disposed at a position overlapping the rotation center of the intake valve 11, and the center position coincides with the rotation axis of the magnet 17. The magnetic detection element 31 of the present embodiment constitutes a main element, and as will be described later, constitutes a magnetic detection element for detecting the rotation angle of the intake valve 11 and detects a magnetic field generated from the magnet 17. Hall element.

  The magnetic detection elements 32 a, 32 b, 32 c, and 32 d are distributed on the upper surface of the substrate 30. The magnetic detection elements 32a, 32b, 32c, and 32d are disposed so that the center of gravity coincides with the center of the upper surface (that is, the position of the magnetic detection element 31). The position of the center of gravity is a position of the center of gravity of a quadrangle whose vertex (corner) is the position of each of the magnetic detection elements 32a, 32b, 32c, and 32d. The vertex is a point where the two sides intersect to form a corner in the rectangle. In the present embodiment, the magnetic detection elements 32 a, 32 b, 32 c, and 32 d are distributed and arranged at the four corners of the upper surface of the substrate 30. The magnetic detection elements 32a, 32b, 32c, and 32d constitute complementary elements. As will be described later, the magnetic detection elements 32a, 32b, 32c, and 32d constitute magnetic detection elements for detecting an assembly error of the sensor assembly 2. Hall element to be detected.

  The signal processing circuit 22a is mounted on a region of the upper surface of the substrate 30 excluding the magnetic detection elements 31, 32a, 32b, 32c, and 32d. The said area | region is the shape of the substantially 10 character which each protrudes toward four sides of an upper surface.

  Moreover, the resin material 50 is filled in the recess 15a of the sensor case 20 of FIG. The resin material 50 is disposed so as to cover the substrate 21 and the magnetic detection IC 22. The resin material 50 is provided to protect the substrate 21 and the magnetic detection IC 22 from water, oil, and dust.

  Next, the electrical configuration of the electronic throttle 1 of the present embodiment will be described with reference to FIG. FIG. 4 is a diagram showing an electrical configuration of the electronic throttle 1. Hereinafter, XYZ coordinates in which the normal position with no position error in the magnetic detection element 31 is the origin, the X axis and the Y axis are orthogonal to the axial direction of the rotary shaft 11a, and the axial direction of the rotary shaft 11a is the Z axis. An example in which is set will be described.

  The magnetic detection element 31 outputs a detection signal indicating the rotation angle θ of the magnet 17 based on the magnetic field generated from the magnet 17. The rotation angle θ indicates the angle of the magnet 17 (that is, the intake valve 11) with respect to the sensor assembly 2. When the X axis is the initial position of the magnet 17, as shown in FIG. Is the angle formed by the direction Y1 connecting the S pole and the X axis and the X axis. In the present embodiment, the range of the rotation angle θ is set between 0 degrees and 90 degrees. The magnetic detection element 31 outputs an output voltage as a detection signal. The magnetic detection element 31 is set so that the output voltage draws a sine wave when the angle θ changes from 0 degrees to 90 degrees.

  The magnetic detection element 32 a outputs a detection signal indicating the magnetic field intensity from the magnet 17 based on the magnetic field generated from the magnet 17. Similarly to the magnetic detection element 32a, the magnetic detection elements 32b, 32c, and 32d output detection signals indicating the magnetic field strength from the magnet 17 based on the magnetic field generated from the magnet 17, respectively.

  The signal processing circuit 22a constitutes signal processing means, and is constituted by a CPU, a memory, and the like. Based on the detection signals of the magnetic detection elements 32a, 32b, 32c, and 32d, the signal processing circuit 22a calculates an assembly error of the sensor assembly 2 among the detection signals of the magnetic detection element 31 in accordance with a command from the electronic control unit 40. Correction value functions α and β and a gain correction value G for canceling are calculated. The signal processing circuit 22a corrects the detection signal of the magnetic detection element 31 based on the correction value functions α and β and the gain correction value G in accordance with a command from the electronic control device 40, and outputs a corrected detection signal. The memory stores mathematical formulas and graphs used to calculate the correction value functions α and β and the gain correction value G. Details of mathematical formulas and graphs will be described later.

  The electronic control unit 40 controls the electric motor 16 in addition to instructing the signal processing circuit 22a to calculate the correction value functions α and β, the gain correction value G, and the correction of the detection signal of the magnetic detection element 31. Execute control processing.

  Next, the manufacturing process of the electronic throttle 1 of this embodiment will be described with reference to FIG. FIG. 6 is a flowchart showing the sequence of the manufacturing process of the electronic throttle 1.

  First, in step S50, the throttle body 10 is prepared by molding such as die casting. In addition to this, as the intake valve 11, a valve body 11c and rotating shafts 11a and 11b are prepared separately. In the next step S51, the rotation shafts 11a and 11b are attached to the throttle body 10, and in the next step S52, the electric motor (referred to as a shaft rotation motor in the figure) 16 and the gears 13, 13a and 13e are throttled. Then, the intake valve 11 is attached to the throttle body 10 in the next step S53. In the next step S54, the support member 15 is attached to the throttle body 10. In the next step S55, the magnet 17 is attached to the support member 15. Thereafter, in step S56, a sensor assembly (referred to as sensor ASSY in the figure) 2 is attached to the throttle body 10. At this time, positioning is performed by fitting the convex portion 20 a of the sensor case 20 of the sensor assembly 2 into the concave portion 10 d of the throttle body 10. Thereafter, the sensor case 20 is fastened to the throttle body 10 with screws (not shown).

  At this time, a gap is generated between the convex portion 20 a of the sensor case 20 and the inner wall of the concave portion 10 d of the throttle body 10, and a subtle position error occurs when the sensor assembly 2 is screwed to the throttle body 10. For this reason, a subtle position error of the magnetic detection element 31 of the magnetic detection IC 22 of the sensor assembly 2 with respect to the magnet 17 occurs. Due to the position error, an error occurs in the detection signal of the magnetic detection element 31. Therefore, in the adjustment process of the next step S57, the signal processing circuit 22a obtains the correction value functions α and β and the gain correction value G for correcting the detection signal of the magnetic detection element 31 and stores them in the memory. Details of the calculation of the correction value functions α and β and the gain correction value G will be described later. In the next step S58, various inspections are performed. Thereafter, the electronic throttle 1 is shipped in step S59.

  Next, a process for obtaining the correction value functions α and β and the gain correction value G according to the present embodiment will be described with reference to FIG. FIG. 7 is a flowchart showing processing for obtaining the correction value functions α and β and the gain correction value G in the signal processing circuit 22a.

  First, the jig electronic control device is connected to the signal processing circuit 22a of the electronic throttle 1 and the electric motor 16.

  First, in step S100, when the rotation angle θ = 0 degrees, the signal processing circuit 22a measures the detection signals of the magnetic detection elements 32a, 32b, 32c, and 32d. The magnetic field strength from the magnet 17 (hereinafter referred to as magnetic field strength Ka) based on the detection signal of the magnetic detection element 32a and the magnetic field strength from the magnet 17 (hereinafter referred to as magnetic field strength Kb) based on the detection signal of the magnetic detection element 32b. And ask.

Here, when the magnetic detection element 31 of the magnetic detection IC 22 of the sensor assembly 2 is disposed at a normal position without a position error (that is, the origin of the XYZ coordinates), as shown in FIG. The distance between the center of the magnet 17 and the distance between the magnetic detection element 32b and the center of the magnet 17 are the same. FIG. 8 is a diagram schematically showing the arrangement relationship between the magnetic detection elements 32 a and 32 b and the magnet 17. In this case, the magnetic field strength Ka and the magnetic field strength Kb are the same. An arrow in FIG. 8 indicates a magnetic field. Also, as shown in FIG. 9, when the sensor assembly 2 approaches the S pole of the magnet 17 due to a displacement of the sensor assembly 2 in the X-axis direction (left-right direction in the drawing). The distance between the magnetic detection element 32 a and the center of the magnet 17 is shorter than the distance between the magnetic detection element 32 b and the S pole of the magnet 17. For this reason, the magnetic field strength Kb is larger than the magnetic field strength Ka. For this reason, the difference amount (= Ka−Kb) of the magnetic field strength Ka with respect to the magnetic field strength Kb indicates the X-axis deviation amount. The X-axis deviation amount represents a component in the X-axis direction in the position error of the sensor assembly 2.

  The memory in the signal processing circuit 22a stores in advance a graph G1 (see FIG. 7) showing the relationship between the difference amount (= Ka−Kb) and the X-axis deviation amount. That is, the relationship between the difference amount (= Ka−Kb) and the X-axis deviation amount is defined in advance by a matrix. In the graph G1, the difference amount (= Ka−Kb) and the X-axis deviation amount are specified on a one-to-one basis, and the X-axis deviation amount increases as the difference amount (= Ka−Kb) increases. Yes.

  In step S110, the X-axis deviation amount is obtained from the difference amount (= Ka−Kb) based on the graph G1. The correction value function α is calculated by substituting into the equation 1 as the X-axis deviation amount x. The correction value function α is a function for correcting an error based on the X-axis deviation amount in the detection signal of the magnetic detection element 31.

α = ax2 + bx + c Expression (1)
The correction value function α thus obtained is stored in the memory.

  Here, a, b, and c in Formula 1 are predetermined numerical values. In order to obtain the correction value function α, the detection signals of the magnetic detection elements 32c and 32d may be used instead of the detection signals of the magnetic detection elements 32a and 32b.

  Next, in step S <b> 120, the jig electronic control device controls the electric motor 16. At this time, the electric motor 16 rotates the intake valve 11 through the gears 13, 13a, and 13e until the rotation angle θ becomes 90 degrees. At this time, the magnetic detection elements 32a and 32c are arranged across the Y axis in the direction in which the N pole and the S pole of the magnet 17 are arranged.

  For this reason, when the magnetic field intensity from the magnet 17 detected by the magnetic detection element 32a is the magnetic field intensity Ka and the magnetic field intensity from the magnet 17 detected by the magnetic detection element 32c is the magnetic field intensity Kc, as in step S110. The difference amount (= Ka−Kc) of the magnetic field strength Ka with respect to the magnetic field strength Kc indicates the Y-axis deviation amount. The magnetic field strength Ka is obtained based on the detection signal of the magnetic detection element 32a. The magnetic field strength Kc is obtained based on the detection signal of the magnetic detection element 32c.

  The memory in the signal processing circuit 22a stores in advance a graph G2 (see FIG. 7) showing the relationship between the difference amount (= Ka−Kc) and the Y-axis deviation amount. That is, the relationship between the difference amount (= Ka−Kc) and the Y-axis deviation amount is defined by the matrix. In the graph G2, the difference amount (= Ka-Kc) and the Y-axis deviation amount are specified on a one-to-one basis, and the Y-axis deviation amount increases as the difference amount (= Ka-Kc) increases. Yes.

  In step S130, the Y-axis deviation amount is obtained from the difference amount (= Ka−Kc) based on the graph G2. The correction value function β is calculated by substituting the Y-axis deviation amount into y in Equation 2. The correction value function β is a function for correcting an error based on the Y-axis deviation amount in the detection signal of the magnetic detection element 31.

β = a′y2 + b′y + c ′ (2)
The correction value function β thus obtained is stored in the memory. Here, a ′, b ′, and c ′ in Expression 2 are predetermined numerical values. In order to obtain the correction value function β, the detection signals of the magnetic detection elements 32b and 32d may be used instead of the detection signals of the magnetic detection elements 32a and 32c.

  Further, as described above, when the electric motor 16 is driven and the intake valve 11 is rotated until the rotation angle θ becomes 0 degree to 90 degrees, the signal processing circuit 22a measures the detection signal of the magnetic detection element 31. Then, the maximum amplitude value of the measured detection signal is obtained. The maximum amplitude value is information indicating the Z-axis deviation.

  The memory in the signal processing circuit 22a stores in advance a graph (not shown) indicating the relationship between the maximum amplitude value and the Z-axis deviation. That is, the relationship between the maximum amplitude value and the Z axis deviation is defined in advance by a matrix. The maximum amplitude value and the Z-axis deviation are specified on a one-to-one basis, and the Z-axis deviation increases as the maximum amplitude value increases.

  In step S140, the Z-axis deviation is obtained based on the graph showing the relationship between the maximum amplitude value and the Z-axis deviation and the maximum amplitude value of the detection signal measured as described above. Based on the obtained Z-axis deviation, the gain correction value G is calculated. The gain correction value G is a gain for correcting an error based on the Z-axis deviation amount in the detection signal of the magnetic detection element 31. The Z-axis deviation and the gain correction value G are specified on a one-to-one basis, and the gain correction value G decreases as the Z-axis deviation increases. The gain correction value G obtained in this way is stored in the memory.

  Next, the operation of the electronic throttle 1 of this embodiment will be described.

  First, when the electronic control unit 40 drives the electric motor 16 to control the rotation angle of the intake valve 11, the electronic control unit 40 instructs the signal processing circuit 22a to output a detection signal after correction of the magnetic detection element 31. . Then, the signal processing circuit 22a reads the correction value functions α and β and the gain correction value G from the memory. Assuming that the detection signal of the magnetic detection element 31 is A and the corrected detection signal after correcting the X-axis deviation is A ′, the corrected detection signal A ′ is obtained by adding the correction value function α to the detection signal. (A ′ = A + α).

  Next, the signal processing circuit 22a obtains a corrected detection signal B (= A ′ + β) in which the Y-axis deviation is corrected by adding the correction value function β to the corrected detection signal A ′. be able to. In addition to this, a corrected detection signal C (= G × B) in which the gain correction value G is multiplied by the corrected detection signal B to correct the Z-axis deviation can be obtained.

  According to the present embodiment described above, in the adjustment process at the time of manufacturing the electronic throttle 1, the signal processing circuit 22a corrects the correction value functions α and β and the gain correction value G for correcting the detection signal of the magnetic detection element 31. And the calculated correction value functions α and β and the gain correction value G are stored in the memory. When receiving a command from the electronic control unit 40, the signal processing circuit 22a corrects the detection signal of the magnetic detection element 31 using the correction value functions α and β and the gain correction value G stored in the memory and performs correction. Is detected and output to the electronic control unit 40. For this reason, the detection accuracy of the rotation angle can be improved.

  In the present embodiment, a magnetic detection IC 22 having a magnetic detection element 31 for detecting a rotation angle is mounted on the upper surface of the substrate 21.

  In Patent Document 1, a support member that extends in a direction orthogonal to the substrate 21 is disposed, and a magnetic detection element for detecting a rotation angle is provided at the tip of the support member. For this reason, the assembly process of the magnetic detection element for detecting the rotation angle with respect to the substrate 21 is complicated. In addition, the size of the electronic throttle 1 in the direction orthogonal to the substrate 21 is increased.

  On the other hand, the magnetic detection IC 22 having the magnetic detection element 31 for detecting the rotation angle is mounted on the upper surface of the substrate 21 as described above. For this reason, the magnetic detection element 31 can be easily assembled. Furthermore, since the support member arranged so as to be orthogonal to the substrate 21 is no longer used, the size of the electronic throttle 1 in the direction orthogonal to the substrate 21 can be suppressed.

  In Patent Document 1, a protrusion having a storage chamber for storing a temperature sensor is provided in the sensor assembly, and the rotation angle sensor is positioned relative to the magnet by inserting the protrusion into a hole in the throttle body.

  On the other hand, in this embodiment, the signal processing circuit 22a corrects the detection signal of the magnetic detection element 31 using the correction value functions α and β and the gain correction value G as described above, and the detection signal after correction. Is calculated. For this reason, the detection accuracy of the rotation angle can be improved regardless of the positioning accuracy by the protrusion of the sensor assembly and the hole of the throttle body. For this reason, it is not necessary to provide a protrusion having a storage chamber for storing the temperature sensor in the sensor assembly 2.

  In the present embodiment, the magnetic detection IC 22 is housed in the recess 23 of the sensor case 20. The magnet 17 enters the recess 24 of the sensor case 20 and faces the ceiling surface 24 a of the recess 24. For this reason, the distance between the magnetism detection elements 31, 32a, 32b, 32c, and 32d and the magnet 17 can be shortened. For this reason, the magnetic detection elements 31, 32a, 32b, 32c, and 32d can detect the magnetic field generated from the magnet 17 with high accuracy. Therefore, the rotation angle θ, the correction value functions α and β, and the gain correction value G of the intake valve 11 can be obtained with high accuracy.

  In the first embodiment, the example in which the Z-axis deviation is corrected after correcting the X-axis deviation and the Y-axis deviation with respect to the detection signal of the magnetic detection element 31 has been described. The X axis deviation and the Y axis deviation may be corrected after the Z axis deviation is corrected with respect to the detection signal of the detection element 31.

  In the first embodiment, the example in which the mathematical expressions and the graphs used for calculating the correction value functions α and β and the gain correction value G are stored in the memory of the signal processing circuit 22a has been described. The mathematical formula and the graph may be stored in the memory of the electronic control device. The electronic control device 40 may be used as the electronic control device for storing the mathematical formula and the graph, or another electronic control device other than the electronic control device 40 may be used.

(Second Embodiment)
In the first embodiment, the signal processing circuit 22a calculates the correction value functions α and β and the gain correction value G and stores them in the memory in the adjustment process when the electronic throttle 1 is manufactured. In the embodiment, instead of this, an assembling error is displayed in the adjustment process at the time of manufacturing the electronic throttle 1.

  On the substrate 30 of the magnetic detection IC 22 of the present embodiment, the magnetic detection elements 31, 32a, 32b, 32c, and 32d are mounted without the signal processing circuit 22a.

  In the present embodiment, the adjustment process at the time of manufacturing the electronic throttle 1 is different from the adjustment process of the first embodiment. For this reason, the adjustment process of this embodiment is demonstrated below.

  First, a magnetic detection IC output calculation device 42, a jig electronic control device 43, and a jig personal computer 41 are prepared as jigs. After that, as shown in FIG. 10, the magnetic detection IC output calculation device 42 and the jig personal computer 41 are connected, and the magnetic detection IC 22, the magnetic detection IC output calculation device 42, and the jig electronic control device 43 are connected, The electric motor 16 is connected to the jig electronic control unit 43. At this time, the magnetic detection IC output calculation device 42 performs a process for obtaining an assembly error based on detection signals as analog signals output from the magnetic detection elements 31, 32a, 32b, 32c, and 32d. Hereinafter, the processing will be described with reference to FIG.

  Steps 100 and 120 in FIG. 11 and steps 100 and 120 in FIG. 7 are the same steps.

  First, in step S100, when the rotation angle θ = 0 degrees, the detection signals of the magnetic detection elements 32a and 32b are measured. The magnetic field strengths Ka and Kb are obtained based on the detection signals of the magnetic detection elements 32a and 32b. Next, in step S110a, as in step S110 of FIG. 7, the X-axis deviation amount is obtained from the difference amount (= Ka−Kb).

  In the next step S120, the electric motor 16 is controlled through the jig electronic control unit 43 to rotate the intake valve 11 until the rotation angle θ reaches 90 degrees. At this time, the detection signals of the magnetic detection elements 32a and 32c are measured. Magnetic field strengths Ka and Kc are obtained based on detection signals of the magnetic detection elements 32a and 32c. Accordingly, the Y-axis deviation amount is obtained from the difference amount (= Ka−Kc). In addition to this, as described above, when the electric motor 16 is driven via the jig electronic control unit 43 and the intake valve 11 is rotated until the rotation angle θ is changed from 0 degree to 90 degrees, the magnetic detection is performed. The maximum amplitude value of the detection signal of the element 31 is obtained. In step S140a, the Z-axis deviation amount is calculated based on the measured maximum amplitude value of the detection signal. The X-axis deviation amount, the Y-axis deviation amount, and the Z-axis deviation amount thus obtained are output to the jig personal computer 41. Accordingly, the jig personal computer 41 displays the X-axis deviation amount, the Y-axis deviation amount, and the Z-axis deviation amount simultaneously on the display. Therefore, the operator can adjust the position of the sensor assembly 2 while viewing the display of the X-axis deviation amount, the Y-axis deviation amount, and the Z-axis deviation amount on the display. That is, the operator can adjust the position of the sensor assembly 2 while monitoring the X-axis deviation amount, the Y-axis deviation amount, and the Z-axis deviation amount.

  According to the present embodiment described above, in the adjustment process at the time of manufacturing the electronic throttle 1, the magnetic detection IC output calculation device 42 uses the X-axis based on the detection signals of the magnetic detection elements 31, 32a, 32b, 32c, and 32d. The shift amount, the Y-axis shift amount, and the Z-axis shift amount are calculated and displayed on the display. For this reason, it is possible to assist the operator in adjusting the position of the sensor assembly 2 with respect to the magnet 17. Thereby, the operator can finely adjust the position of the sensor assembly 2. Therefore, it is possible to adjust the position of the rotation angle detection magnetic detection element with respect to the magnet with high accuracy. Therefore, as in the first embodiment, the detection accuracy of the rotation angle can be improved.

  In the present embodiment, in the adjustment process at the time of manufacturing the electronic throttle 1, the magnetic detection IC output calculation device 42 calculates the X-axis deviation amount, the Y-axis deviation amount, and the Z-axis deviation amount. For this reason, it is not necessary to provide the magnetic detection IC output calculation device 42 in the magnetic detection IC 22 by using the magnetic detection IC output calculation device 42 as a jig. For this reason, the circuit configuration of the magnetic detection IC 22 can be simplified.

  In the second embodiment, the jig personal computer 41 shows an example in which the X-axis deviation amount, the Y-axis deviation amount, and the Z-axis deviation amount are simultaneously displayed on the display. In 41, any one of the X-axis shift amount, the Y-axis shift amount, and the Z-axis shift amount may be displayed, and the displayed shift amount may be switched.

  In the second embodiment, the magnetic detection IC output calculation device 42 calculates and outputs the X-axis misalignment amount, the Y-axis misalignment amount, and the Z-axis misalignment amount to the jig personal computer 41 to output the sensor assembly. 2, the magnetic detection IC output arithmetic unit 42 uses an automatic assembly device that adjusts the position of the sensor assembly 2 to replace the X-axis deviation amount, the Y-axis deviation amount, and the Z-axis. The sensor assembly is calculated based on the X-axis deviation amount, the Y-axis deviation amount, and the Z-axis deviation amount output from the magnetic detection IC output calculation device 42 by calculating the axis deviation amount and outputting it to the automatic assembly device. 2 position adjustment control is performed. In this case, the magnetic detection IC output calculation device 42 outputs the X-axis deviation amount, the Y-axis deviation amount, and the Z-axis deviation amount to the automatic assembly device, thereby assisting the control of the position adjustment of the sensor assembly 2 by the automatic assembly device. can do. Therefore, the automatic assembly apparatus can finely adjust the position of the sensor assembly 2.

  In the first and second embodiments, the example in which the temperature sensor is mounted on the substrate 21 has been shown. Instead, as shown in FIG. 12, the sensor assembly 2 has a storage chamber for storing the temperature sensor 25 as shown in FIG. The sensor assembly 2 may be positioned with respect to the magnet 17 by providing the protrusion 24 having the protrusion 24 and inserting the protrusion 24 into the hole of the throttle body 10.

  In the first and second embodiments, the example in which the magnetic detection IC 22 (see FIG. 3) is used as the rotation angle detection device is shown, but not limited to this, as shown in FIG. You may use the magnetic detection unit 22 which mounts the magnetic detection elements 32a, 32b, 32c, and 32d on the board | substrate 30. FIG.

  In the first and second embodiments, the example in which the four magnetic detection elements 32a, 32b, 32c, and 32d are provided as the magnetic detection elements for assembly error detection is shown. It is sufficient that a plurality of error detecting magnetic detection elements are arranged so as to obtain a deviation amount indicating an assembling error, and the number is not limited to four, and three or five or more magnetic detection elements are provided. The amount of deviation in the X-axis, Y-axis, and Z-axis directions may be obtained.

  In the first and second embodiments, the example in which the intake valve 11 is used as the rotating body has been described. However, instead of this, a member other than the intake valve 11 may be used as the rotating body.

DESCRIPTION OF SYMBOLS 1 Electronic throttle 2 Sensor assembly 3 Throttle body assembly 10 Throttle body 10A Intake path 11 Intake valve (rotary body)
11a, 11b Rotating shaft 13, 13a, 13e Gear 14 Protective case 15 Support member 16 Electric motor 17 Magnet 20 Sensor case 21 Substrate (printed substrate)
30 Substrate (silicon substrate)
22 Magnetic detection IC
31 Magnetic detecting element for detecting rotation angle 32a to 32d Magnetic detecting element for detecting error

Claims (10)

A main element that outputs a detection signal indicating a rotation angle of the rotating body based on a magnetic field formed by a magnet that rotates with the rotation of the rotating body, the center position of the main element being the rotation axis of the magnet; A rotation angle detection device assembled to match
Around the main element, a plurality of auxiliary elements that respectively output detection signals based on the magnetic field formed by the magnet are arranged,
Based on detection signals output from the plurality of complementary elements, a deviation amount between the center position of the main element and the rotation axis of the magnet is obtained, and a detection signal output from the main element is calculated based on the deviation amount. A rotation angle detecting device comprising a signal processing means for correcting.   The rotation angle detection device according to claim 1, wherein the main element is arranged at the center of gravity of a polygon having apexes at the positions of the plurality of complementary elements. In the XYZ coordinate system in which the rotation axis of the magnet is a Z-axis, and the axes orthogonal to each other are the X-axis and the Y-axis, the plurality of complementary elements are X-coordinate positions of the main element in the X-axis direction. Is disposed at a position that is symmetric with respect to the Y-axis position of the main element in the Y-axis direction,
The signal processing means is configured such that when the angle formed between the N-pole and S-pole of the magnet and the X-axis is 0 degree, a deviation in the X-axis direction between the center position of the main element and the rotation axis of the magnet. 3. The rotation angle detection according to claim 1, wherein when the angle is 90 degrees, a shift amount in the Y-axis direction between the center position of the main element and the rotation axis of the magnet is obtained. apparatus.   The signal processing means is configured such that a Z position between the center position of the main element and the rotation axis of the magnet is based on the maximum amplitude value of the detection signal output from the main element when the angle changes from 0 degrees to 90 degrees. The rotation angle detection device according to claim 3, wherein an axial shift amount is obtained.   The rotation according to any one of claims 1 to 4, wherein the magnet is arranged so that a direction connecting the north pole and the south pole is perpendicular to the axial direction of the rotation shaft. Angle detection device.   The rotation angle detection device according to claim 1, wherein the main element and the plurality of complementary elements are mounted on a substrate. The substrate is formed in a square,
The rotation angle detection device according to claim 6, wherein four complementary elements as the plurality of complementary elements are distributed and arranged at four corners of the substrate.   7. The rotation angle detection device according to claim 1, wherein a signal processing circuit constituting the signal processing means is mounted on the substrate.   The rotation angle detection device according to claim 7, wherein the signal processing circuit is disposed on one surface of the substrate on which the main element and the plurality of complementary elements are mounted. A rotation angle detection device including a main element that outputs a detection signal indicating a rotation angle of the rotating body based on a magnetic field formed by the magnet with respect to a body having a magnet that rotates as the rotating body rotates. A method for assembling a rotation angle detector that is assembled so that the center position of the main element coincides with the rotation axis of the magnet,
In the rotation angle detection device, a plurality of auxiliary elements that output detection signals based on the magnetic field formed by the magnet are arranged around the main element,
An adjustment step of adjusting the assembly position of the rotation angle detection device with respect to the body;
In this adjustment step, based on detection signals output from the plurality of complementary elements, a deviation amount between the center position of the main element and the rotation axis of the magnet is obtained, and this deviation amount is used to adjust the assembly position. A method of assembling the rotation angle detecting device, characterized in that

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