JP2012083212A - Rotation angle detection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotation angle detection device capable of detecting a rotation angle with high accuracy even when unavoidable concentricity arises between a rotor and a hall IC.SOLUTION: In a rotation angle detection device, when fitting a cap 21 having a magnet MG attached thereto to a rotary shaft 15 set at a required rotation angle, the cap 21 is fitted to the rotary shaft 15 so that a line segment connecting marker grooves formed on the magnet MG coincides with a line segment connecting a pair of screw holes formed in a housing to screw bolts therein when viewed from Z direction. A case 31 having a hall IC is fixed to the housing by inserting the bolts into shaft holes 33 in both of support projections 32 and screwing the bolts into the screw holes. The hall IC provided in the case 31 has a detection surface disposed in parallel with the magnet MG, and a central axis line C1 of the rotary shaft 15 passes through a center point of the detection surface. Further, a line segment connecting one of two hall device set formed in a semiconductor substrate of the hall IC coincides with the line segment connecting the marker grooves when viewed from Z direction.

Description

  The present invention relates to a rotation angle detection device.

  The Hall IC that detects the rotation angle of the rotating body by detecting the rotation angle of the magnet that is attached to the rotation center axis of the rotating body and rotates around the rotation center axis together with the rotating body rotates its detection surface. The rotation angle θ of the magnet is detected by arranging it in parallel with the magnet (Non-patent Document 1).

  As shown in FIG. 8, the magnet 3 attached to the Hall IC 1 and the rotating body 2 has a central axis extending perpendicularly from the center point P0 of the detection surface 1a of the Hall IC 1 and a rotation center axis (rotating body 2 of the magnet 3). The rotation center axis C0) is relatively arranged. Accordingly, the Hall IC 1 detects the rotation angle θ of the magnet 3 that rotates about the rotation center axis C0.

  The Hall IC 1 has four Hall elements formed on a resin-molded semiconductor substrate. The semiconductor substrate on which the four Hall elements are formed is arranged in parallel with the detection surface 1a, and is parallel to the detection surface 1a. The rotation angle θ of the magnet 3 that rotates in the direction is detected.

  The magnet 3 has an N pole formed on one side and a S pole formed on the other side with a boundary line orthogonal to the rotation center axis C0. Thus, when the magnet 3 rotates about the rotation center axis C0, the vector of the external magnetic field of the magnet 3 rotates about the rotation center axis C0.

  The Hall IC 1 has four Hall elements, one set each, and the two Hall elements in one set detect the X-direction component Bx of the external magnetic field of the rotating magnet 3 and the other set. Two Hall elements detect the Y-direction component By of the external magnetic field of the rotating magnet 3.

  The Hall IC 1 detects the vector (rotation angle) of the external magnetic field of the magnet 3 that rotates around the rotation center axis C0 in parallel with the detection surface 1a from the detected X direction component Bx and Y direction component By of the external magnetic field of the magnet 3. θ) is detected using the following formula.

θ = tan −1 (Bx / By)
The four Hall elements formed on the semiconductor substrate are arranged at equal intervals of 90 ° around the center point of the semiconductor substrate (the point where the central axis line C0 passes vertically). Then, the two Hall elements of each set are arranged at symmetrical positions with the center point in between, and the Hall elements of both sets are arranged equidistant from the center point.

  Further, a magnetic collecting film is formed on the semiconductor substrate on which the four Hall elements are formed. The magnetic collecting film is a film that changes the direction of an external magnetic field that is output in parallel from the magnet 3 that rotates in parallel to the detection surface 1a to a direction orthogonal to the substrate surface of the semiconductor substrate and collects the magnetic force on the substrate surface. As a result, the X-direction component Bx detected by the two Hall elements of one set and the Y-direction component By detected by the two Hall elements of the other set are relatively controlled by the rotation angle θ of the magnet 3. Change.

  Then, the X direction component Bx and the Y direction component By are detected, and a detection voltage relative to the rotation angle θ of the magnet 3 is output from the Hall IC 1 from the above formula. Therefore, by knowing the detection voltage from the Hall IC 1, the rotation angle θ of the magnet 3 (rotating body 2) can be known in the range of 0 to 360 °.

Melexis 90316 IC data sheet

  By the way, in order to detect the rotation angle θ of the magnet 3 with high accuracy, the center axis extending perpendicularly from the center point P0 of the detection surface 1a of the Hall IC 1 and the rotation center axis C0 of the magnet 3 coincide with each other without misalignment. Thus, it is necessary to assemble the Hall IC 1 and the magnet 3.

  Here, the amount of positional deviation between the center axis of the Hall IC and the rotation center axis C0 of the magnet 3 is called coaxiality. This misalignment is caused by (1) assembly of Hall IC 1 and magnet 3, (2) inherent magnetic pole displacement of magnet, (3) eccentric rotation of rotating body, (4) looseness when vibrating, etc. There is a cause to cause.

However, in any case, there is a limit to setting this positional shift amount (coaxiality) to zero, and it has not been possible to detect a highly accurate rotation angle.
The present invention has been made to solve the above-described problems, and its purpose is to detect a rotation angle with high accuracy even if an inevitable coaxiality occurs between the rotating body and the Hall IC. It is to provide a detection device.

The invention described in claim 1
The magnet is rotated on a detection surface of the Hall IC on a plane parallel to the detection surface, and the Hall IC and the center of the Hall IC are aligned so that the central axis of the rotation center of the magnet coincides with the central axis of the detection surface of the Hall IC. Magnets are arranged relatively, and the direction of the magnetic field of the rotating magnet is detected by the Hall IC as a first orthogonal component and a second orthogonal component orthogonal to each other, and from the ratio of the first orthogonal component and the second orthogonal component A rotation angle detection device for detecting a rotation angle of the magnet as a magnetic field vector, wherein the magnet is provided with a mark indicating the magnetic pole direction of the NS pole, and the magnetic pole direction of the magnet is set to a first specific rotation angle position. The detection direction of the first orthogonal component or the detection direction of the second orthogonal component of the detection surface is set to the Hall IC with respect to the magnet at the set position. The Hall IC with respect to the magnetic pole direction of the magnet at a second specific rotation angle position rotated by a specific rotation angle of the first specific rotation angle position with respect to the magnetic pole direction of the NS pole of the mark provided on the magnet The detection directions are shifted by the specific rotation angle.

  According to the first aspect of the present invention, while looking at the mark of the magnet, the detection surface of the Hall IC may be such that the detection direction of the first orthogonal component or the detection direction of the second orthogonal component coincides with the direction of the magnetic pole of the magnet. The Hall IC can be arranged relative to the magnet.

  According to a second aspect of the present invention, in the rotation angle detection device according to the first aspect, the magnet is a covered cylindrical cap attached to a shaft end portion of a rotation shaft that is rotatably supported by the housing. Attached to the outer surface of the lid portion, the casing is provided with an index for alignment of the mark formed on the magnet, and the Hall IC is accommodated in a case fixed to the casing. Is the specific rotation at the first specific rotation angle position when the detection direction of the detection surface of the Hall IC is fixed to the housing with respect to the magnetic pole direction of the NS pole of the mark provided on the magnet. A connecting portion for connecting to the housing is provided so as to be in the direction of the second specific rotation angle position rotated by an angle and so that the center point of the detection surface and the center point of the magnet coincide with each other. .

  According to the second aspect of the present invention, the magnet attached to the rotating shaft can be attached to the casing in accordance with the direction of the magnetic pole of the magnet according to the index, and the case is connected and fixed to the casing. The detection direction of the detection surface of the Hall IC can be matched with the direction of the magnetic pole of the magnet.

  According to a third aspect of the present invention, in the rotation angle detection device according to the second aspect, the index for positioning the magnet provided on the casing is connected to the casing provided on the case. It is a screw hole screwed with the bolt of the connecting portion.

According to the third aspect of the present invention, the magnet attached to the rotating shaft can match the direction of the magnetic pole of the magnet using the screw hole formed in the housing as an index.
According to a fourth aspect of the present invention, in the rotation angle detection device according to any one of the first to third aspects, the magnet is a disk-shaped magnet, and the center point thereof is orthogonal and N on one side. Marks were formed at two locations on the boundary line that bisects the N magnetic pole region of the pole and the S magnetic pole region of the S pole on the other side.

  According to the invention described in claim 4, when the detection direction of the detection surface of the Hall IC coincides with the direction of the magnetic pole of the magnet, the Hall IC can be disposed relative to the magnet while looking at the mark of the magnet MG. it can.

  According to a fifth aspect of the present invention, in the rotation angle detection device according to the third or fourth aspect, two cap-side marks facing each other across the center point are formed on the outer peripheral edge of the lid outer surface. In addition, the magnet-side marks formed at two locations of the magnet have the interval between the marks coincided with the interval between the cap-side marks.

  According to the fifth aspect of the present invention, the cap can be attached so that the center point of the outer surface of the lid portion of the cap coincides with the center point of the magnet. Therefore, the cap and the magnet rotate around the rotation axis of the rotation shaft.

  The invention according to claim 6 rotates the magnet on the detection surface of the Hall IC on a surface parallel to the detection surface, and the central axis of the rotation center of the magnet coincides with the central axis of the detection surface of the Hall IC. The Hall IC and the magnet are arranged relative to each other, and the direction of the magnetic field of the rotating magnet is detected by the Hall IC as a first orthogonal component and a second orthogonal component that are orthogonal to each other, and the first orthogonal component is detected. And a rotation angle detector that detects the rotation angle of the magnet as a magnetic field vector from the ratio of the second orthogonal component and the magnet is mounted on a shaft end of a rotation shaft that is rotatably supported by a housing. The cap is attached to the outer surface of the lid portion of the covered cylindrical cap, and a mark indicating the magnetic pole direction of the NS pole of the magnet is provided on the cap, and the cap is attached to the magnetic pole of the magnet. The direction is set to the first specific rotation angle position, and the detection direction of the first orthogonal component or the detection direction of the second orthogonal component of the detection surface is the Hall IC with respect to the magnet at the set position. The Hall IC has a second specific rotation angle position rotated by a specific rotation angle position of the first specific rotation angle position with respect to the magnetic pole direction of the NS pole of the mark provided on the cap with respect to the magnetic pole direction of the magnet. The detection direction was shifted by the specific rotation angle.

  According to the sixth aspect of the present invention, while looking at the mark of the cap so that the detection direction of the first orthogonal component or the detection direction of the second orthogonal component coincides with the magnetic pole direction of the magnet on the detection surface of the Hall IC. The Hall IC can be arranged relative to the magnet.

  According to the present invention, it is possible to detect the rotation angle with high accuracy even if an inevitable coaxiality occurs between the rotating body and the Hall IC.

Overall view of the rotary valve device. The expansion perspective view which shows the attachment state of a rotation angle detection apparatus. The exploded perspective view of a rotation angle detection apparatus. The exploded perspective view of a rotation angle detection apparatus. The external appearance perspective view of Hall IC. The perspective view for demonstrating a Hall element. The figure which shows the output voltage of Hall IC with respect to the rotation angle of a magnet. The figure which shows the positional relationship of Hall IC and a magnet for calculating | requiring the rotation angle of the magnet using Hall IC.

Hereinafter, an embodiment in which a rotation angle detection device of the present invention is embodied in a rotary valve device will be described with reference to the drawings.
FIG. 1 is an overall view of the rotary valve device 10, and four first to fourth flow paths 11 to 14 are formed side by side in one direction (hereinafter referred to as the Z direction) in the housing 10 a. As for the 1st-4th flow paths 11-14, the 1st-4th rotary valve RB1-RB4 corresponding, respectively is accommodated in the exit parts 11a-14a.

  The first to fourth rotary valves RB1 to RB4 are fixed to a rotary shaft 15 (see FIG. 3) penetrating through the outlet portions 11a to 14a of the first to fourth flow paths 11 to 14 in the Z direction. When the rotary shaft 15 rotates about the central axis C1 of the coaxial 15, the first to fourth rotary valves RB1 to RB4 also rotate about the central axis C1.

And the opening degree of the exit parts 11a-14a of the 1st-4th flow paths 11-14 is adjusted by 1st-4th rotary valve RB1-RB4 rotating centering on the central axis C1.
Both sides of the rotary shaft 15 are rotatably supported by bearings provided on the housing 10a of the rotary valve device 10, and both shaft ends protrude from the housing 10a. One end of the rotary shaft 15 protruding from the housing 10a is connected to a motor 16 fixed to the housing 10a. And the rotating shaft 15 rotates based on the drive of the motor 16, and 1st-4th rotary valve RB1-RB4 is rotated.

On the other hand, as shown in FIGS. 2, 3, and 4, a rotation angle detection device 20 is provided at the other shaft end of the rotation shaft 15 protruding from the housing 10 a.
The rotation angle detection device 20 is fitted to the other shaft end of the rotation shaft 15 and rotates integrally with the rotation shaft 15, and a case 31 that is fixed to the housing 10a and detects the rotation angle of the rotation shaft 15. It has.

  The cap 21 is made of a covered cylindrical synthetic resin, and the other shaft end of the rotary shaft 15 is fitted into the cap 21. The outer surface 22a of the lid portion 22 of the cap 21 is circular, and the center axis passing through the center point of the outer surface 22a is fitted so as to coincide with the center axis C1 of the rotating shaft 15. . The circular outer surface 22a of the lid portion 22 is a plane that intersects perpendicularly to the central axis C1 extending in the Z direction.

Therefore, when the rotating shaft 15 rotates, the cap 21 rotates around the central axis C <b> 1 of the rotating shaft 15.
In addition, a cap-side mark groove 24 for a mark having the same shape is formed on the side edge of the lid portion 22 that faces each other across the center point of the outer surface 22a.

  A magnet MG is attached to the outer surface 22 a of the lid portion 22. The magnet MG has a disk shape with a predetermined thickness, and has an N pole region An with N poles on one side and a S pole on the other side with a boundary line L1 orthogonal to the center point P1. The S magnetic pole region As is formed in two. The magnet MG is attached to the outer surface 22a of the lid 22 so that the center point P1 of the magnet MG coincides with the center point of the lid 22.

  More specifically, the disc-shaped magnet MG has a magnet-side mark groove 25 for a mark having the same shape by cutting out two places on the boundary line L1 at the outer periphery of the magnet MG and sandwiching the center point P1. Yes. The gap between the pair of magnet side mark grooves 25 facing each other across the center point P1 is formed to coincide with the distance between the pair of opposite cap side mark grooves 24 formed in the cap 21.

  Then, the magnet MG is attached to the outer surface 22 a of the lid portion 22 so that the magnet side marker groove 25 is aligned with the cap side marker groove 24 formed in the lid portion 22. At this time, the line segment connecting the cap-side mark grooves 24 facing each other of the lid portion 22 coincides with the boundary line L1 of the magnet MG as viewed from the Z direction. Moreover, the center point P <b> 1 of the magnet MG coincides with the center point of the outer surface 22 a of the lid portion 22.

  The case 31 has support protrusions 32 formed on both outer side surfaces, and shaft holes 33 are formed through the support protrusions 32. The shaft hole 33 of the support protrusion 32 is aligned with screw holes formed at both side positions of the other shaft end portion of the rotating shaft 15 protruding from the housing 10a. Then, a bolt 34 is inserted through the shaft hole 33, and the case 31 is fixed to the housing 10a by screwing the bolt 34 into the screw hole.

At this time, the case 31 is fixed to the housing 10a in a state of including the other shaft end portion of the rotating shaft 15 to which the cap 21 is attached.
As shown in FIG. 4, the Hall IC 40 is disposed in the case 31. The Hall IC 40 is mounted on a printed wiring board PWA that is fixed to the inner side surface of the case 31. As shown in FIG. 5, the Hall IC 40 has a rectangular outer shape. As shown in FIG. 6, the semiconductor substrate SUB on which the four Hall elements 41 are formed is resin-molded, and external terminals T are formed from both side surfaces. Is extended. The Hall IC 40 is connected to an electric circuit in which external terminals T extending from both side surfaces are formed on the printed wiring board PWA.

  The Hall IC 40 is disposed so as to face the surface opposite to the printed wiring board PWA as a detection surface 40a, and the detection surface 40a is parallel to the outer surface 22a of the lid portion 22 of the cap 21 to which the magnet MG is attached. ing. At this time, the center axis C1 of the rotating shaft 15 passing through the center point P1 of the magnet MG passes through the center point P2 of the detection surface 40a of the Hall IC 40.

  In the resin-molded semiconductor substrate SUB, the substrate surface Sa on which the four Hall elements 41 are formed is arranged in parallel to the detection surface 40a side, and the center point P3 of the substrate surface Sa is set as the center point of the detection surface 40a. It is matched with P2.

  The four Hall elements 41 formed on the substrate surface Sa are arranged at equal intervals of 90 ° in the circumferential direction around the center point P3 of the substrate surface Sa. Two sets of two Hall elements 41 facing each other across the center point P3 are made.

  Here, in order to distinguish between the two hall elements 41 in one set and the two hall elements 41 in the other set, the reference numerals of the two hall elements 41 in one set are “41A” and the other The reference numerals of the two Hall elements 41 in the set are expressed as “41B”.

  A line connecting the two hall elements 41A of one set is orthogonal to the central axis C1 of the rotating shaft 15 and between the pair of shaft holes formed in the support protrusions 32 when viewed from the Z direction. It matches the line segment that connects.

In the present embodiment, for convenience of explanation, the direction in which the line segment connecting the Hall elements 41A extends is the X direction, and the direction in which the line segment connecting the two Hall elements 41B extends is the Y direction.
A magnetism collecting film 42 is formed on the substrate surface Sa on which the four Hall elements 41A and 41B are formed. The magnetic flux collecting film 42 is a film that changes the direction of the external magnetic field that emerges in parallel from the magnet MG that rotates in parallel with the substrate surface Sa to a direction perpendicular to the substrate surface Sa and collects the magnetic force on the substrate surface Sa.

  Then, with respect to the magnet MG rotating around the central axis C1 of the rotation shaft 15 in parallel with the detection surface 40a, the two Hall elements 41A in one set are rotated in the X direction component of the external magnetic field of the magnet MG at that time. Bx is detected, and the other two Hall elements 41B detect the Y-direction component By of the external magnetic field of the rotating magnet MG at that time.

  Accordingly, the Hall IC 40 detects the external magnetic field of the magnet MG that rotates around the central axis C1 in parallel with the detection surface 40a (substrate surface Sa) from the detected X-direction component Bx and Y-direction component By of the external magnetic field of the magnet MG. The vector (rotation angle θ) is detected using the following calculation formula.

θ = tan −1 (Bx / By)
By calculating the rotation angle θ of the magnet MG, the rotation angle θ of the rotating shaft 15, that is, the opening degrees of the first to fourth rotary valves RB1 to RB4 can be detected.

Next, a method for assembling the rotation angle detection device 20 to the rotary valve device 10 will be described.
First, for the Hall IC 40, the output voltage V of the Hall IC 40 with respect to the rotation angle θ of the rotating magnet MG is inspected by experiments or the like.

  Here, the magnet MG is disposed in parallel with the detection surface 40a of the Hall IC 40, and the line segment connecting the two Hall elements 41A of the Hall IC 40 and the boundary line L1 of the magnet MG are viewed from the Z direction. Arrange to match. In this state, the rotation angle θ of the magnet MG is set to 0 degree. Then, the output voltage V of the Hall IC 40 with respect to the current rotation angle θ of the magnet MG rotating around the central axis C1 is obtained.

By this inspection, the present applicant found a certain regularity with respect to the output voltage V of the Hall IC 40 with respect to the rotation angle θ of the magnet MG.
That is, it has been found that the output voltage V of the Hall IC 40 with respect to the rotation angle θ of the magnet MG does not become linear as shown by the characteristic line K0 in FIG. 7, but becomes characteristic lines K1, K2, and K3.

  The reason why the characteristic lines K1, K2, and K3 shown in FIG. 7 are not linear is that the center point P2 of the detection surface 40a does not coincide with the center point P1 of the magnet MG, that is, the center point P2 of the detection surface 40a and the magnet MG. This is because the center point P <b> 1 is not on the center axis C <b> 1 of the rotation shaft 15 and is displaced.

This indicates that the characteristic line K3 having a larger positional deviation amount (coaxiality) has a larger variation with respect to the linear characteristic line K0.
Further, as is apparent from FIG. 7, the characteristic lines K1, K2, and K3 that vary with respect to the linear characteristic line K0 both vary with periodicity, and both become linear characteristic lines K0 in a specific rotation angle band. It was also found that the convergence was repeated.

  That is, in FIG. 7, the rotation angle θ of the magnet MG with respect to the Hall IC 40 is 0 degrees, 90 degrees, 180 degrees, 270 degrees, 360 degrees (hereinafter referred to as “the positional deviation amount (coaxiality))”. When these are referred to as specific rotation angle positions, the output voltages V of the characteristic lines K1, K2, and K3 are found to be the same as the linear characteristic line K0 without greatly differing.

  In other words, it can be seen that the Hall IC 40 outputs the output voltage V for the specific rotation angle position having the same value when the rotation angle θ of the magnet MG is at each specific rotation angle position even if there is a positional shift. . Conversely, it has also been found that there is a rotation angle band that is easily affected by the degree of coaxiality (position shift amount).

  Therefore, when there is a rotation position (high-accuracy rotation detection position) where it is desired to detect the rotation positions of the Hall IC 40 and the magnet MG with high accuracy, the rotation angle of the magnet MG is adjusted to the rotation angle of the high-precision rotation detection position. Further, the Hall IC 40 is relatively arranged with respect to the magnet MG whose rotation angle is matched with the high-precision rotation detection position so that the relative angle is one of the specific rotation angle positions.

  Accordingly, when the magnet MG rotates to the high-precision rotation detection position, the rotation angle θ of the magnet MG becomes a specific rotation angle position with respect to the Hall IC 40. As a result, the Hall IC 40 can detect the high-precision rotation detection position of the magnet MG with high accuracy without being affected by the amount of positional deviation (coaxiality).

Next, a method of assembling the rotation angle detection device 20 to the rotary valve device 10 will be described based on the results obtained by the above inspection.
(Setting of the rotational position of the rotary shaft 15 of the rotary valve device 10)
First, the rotary shaft 15 to which the first to fourth rotary valves RB1 to RB4 are fixed is arranged so that the opening degrees of the first to fourth rotary valves RB1 to RB4 are the opening positions where the most accurate detection is required. The rotation position of the rotary shaft 15 is set by rotating.

  As a result, by setting the rotational position of the rotary shaft 15, the first to fourth rotary valves RB1 to RB4 are most open at the outlet portions 11a to 14a of the first to fourth flow paths 11 to 14. It is set to an opening position where high-precision detection is required.

The opening position where the most accurate detection is required may be a common opening of the first to fourth rotary valves RB1 to RB4, or the first to fourth rotary valves RB1 to RB4. The opening degree for any one of the valves may be used.
(Attaching the cap 21 to the rotating shaft 15)
Next, the rotary shaft 15 in a state where the opening degree of the first to fourth rotary valves RB1 to RB4 is set to the opening position where the most accurate detection is required, and the rotary shaft protruding from the housing 10a A cap 21 having a magnet MG attached thereto is fitted to the other side shaft end portion of 15.

  When the cap 21 is fitted, the boundary line L1 that bisects the N-pole N-pole region An and the S-pole S-pole region As of the magnet MG aligned and attached to the cap-side mark groove 24 in the lid portion 22 Is aligned with the line segment connecting the pair of screw holes to which the bolts 34 formed in the housing 10a are screwed, as viewed from the Z direction (this position is referred to as a first specific angle position). 15 is fitted.

That is, it is performed while aligning the pair of magnet side mark grooves 25 formed in the magnet MG with the pair of screw holes.
(Attaching the case 31 to the housing 10a)
In the case 31 having the Hall IC 40, a bolt 34 is inserted into the shaft hole 33 of the support protrusion 32 formed on both outer side surfaces, and the bolt 34 is screwed into a screw hole formed in the housing 10a, thereby forming a housing. It is fixed to the body 10a.

  By fixing the case 31 to the housing 10a, the Hall IC 40 arranged in the case 31 has a detection surface 40a arranged in parallel with the magnet MG, and a center point P2 of the detection surface 40a on the rotation shaft 15. The central axis C1 passes. In addition, a line connecting the two Hall elements 41A of one set formed on the semiconductor substrate SUB of the Hall IC 40 is a line connecting a pair of screw holes formed in the housing 10a, that is, the magnet MG. The boundary line L1 that bisects the N pole area An of the N pole and the S pole area As of the S pole is coincident when viewed from the Z direction (this position is referred to as a second specific angle position).

When the mounting of the case 31 to the housing 10a is completed, the assembly of the rotation angle detection device 20 to the rotary valve device 10 is completed.
That is, the direction of the NS magnetic pole of the magnet MG with respect to the detection surface 40a of the Hall IC 40 is a direction (Y direction) orthogonal to the line segment connecting the two Hall elements 41A of one set. Therefore, the rotation angle θ of the magnet MG with respect to the Hall IC 40 becomes a specific rotation angle of 90 degrees, and the Hall IC 40 determines the opening degree of the first to fourth rotary valves RB1 to RB4 that require the most accurate detection. Detection can be performed with high accuracy without being affected by the magnitude of the quantity (coaxiality).

Next, effects of the embodiment configured as described above will be described below.
(1) According to the above-described embodiment, the rotation shaft 15 is set at the high-precision rotation detection position, and the cap 21 having the magnet MG attached to the rotation shaft 15 at the high-precision rotation detection position is connected to the boundary of the magnet MG. The line L1 is fitted to the rotating shaft 15 so as to coincide with a line segment connecting the pair of screw holes formed in the housing 10a when viewed from the Z direction.

  The case 31 including the Hall IC 40 passes through the center point P2 of the detection surface 40a of the Hall IC 40 through the center axis C1 of the rotation shaft 15, and two sets of one set formed on the semiconductor substrate SUB of the Hall IC 40. The line segment connecting the Hall elements 41A is fixed to the housing 10a so as to coincide with the boundary line L1 of the magnet MG when viewed from the Z direction.

That is, the direction of the NS magnetic pole of the magnet MG is adjusted to a rotation angle θ of the magnet MG with respect to the Hall IC 40 and a specific rotation angle of 90 degrees.
Therefore, the Hall IC 40 can set the rotation angle θ of the magnet MG relative to the Hall IC 40 to a specific rotation angle of 90 degrees when the first to fourth rotary valves RB1 to RB4 are required to be detected with the highest accuracy. it can.

As a result, the Hall IC 40 can accurately adjust the opening degree of the first to fourth rotary valves RB1 to RB4 that are required to be detected with the highest accuracy without being influenced by the amount of positional deviation (coaxiality). Can be detected.
(2) According to the above-described embodiment, the magnet side marker for markings is provided at two locations on the boundary line L1 that bisects the N magnetic pole region An and the S magnetic pole region As with the outer peripheral edge of the magnet MG and sandwiching the center point P1. A groove 25 was formed. In addition, a cap-side mark groove 24 for a mark is formed on the side edge of the lid portion 22 that faces each other across the center point of the outer surface 22a.

  Therefore, the positioning of the magnet MG with respect to the cap 21 can be easily performed with high accuracy. In addition, the cap 21 can be easily arranged and fixed at the position of the specific rotation angle with respect to the rotation shaft 15 set at the rotation position where the most accurate detection is required.

  Further, when the cap 21 is disposed and fixed at a specific rotation angle position, a boundary line L1 that bisects the N magnetic pole region An and the S magnetic pole region As of the magnet MG screws the bolt 34 formed on the housing 10a. The cap 21 was fitted to the rotating shaft 15 so as to coincide with a line segment connecting the pair of screw holes.

Therefore, by simply fixing the case 31 to the casing 10a up to the bolt, the Hall IC 40 can be easily arranged relative to the magnet MG at a specific rotation angle.
(3) According to the above embodiment, the pair of magnet side mark grooves 25 formed in the magnet MG is formed on the boundary line L1 that bisects the N magnetic pole region An and the S magnetic pole region As of the magnet MG. As a result, when the boundary line L1 of the magnet MG matches the line segment connecting the pair of screw holes to which the bolts 34 formed in the housing 10a are screwed, as viewed from the Z direction, the pair of magnets formed on the magnet MG side. By simply aligning the mark groove 25 with the pair of screw holes, high-accuracy alignment can be easily performed.

In addition, you may change the said embodiment as follows.
In the above embodiment, the magnet side mark grooves 25 are formed at two locations on the boundary line L1 that bisects the N magnetic pole region An and the S magnetic pole region As of the magnet MG. Even if magnet side mark grooves are formed at two locations on a line rotated 90 degrees around the center point P1 with respect to the boundary line L1 that bisects the N magnetic pole area An and the S magnetic pole area As of the magnet MG, Good.

Of course, a plurality of magnet side mark grooves 25 may be formed on the outer peripheral edge of the magnet MG at intervals of 90 degrees starting from the boundary line L1 of the magnet MG.
In the above-described embodiment, the outer peripheral edge of the magnet MG is cut out to form the magnet-side mark groove 25. However, the magnet-side mark groove 25 is not limited to the groove.

In the above embodiment, the rotation angle detection device 20 is embodied in the rotary valve device 10, but may be embodied in other devices that require detection of the rotation angle.
In the above embodiment, in the alignment when the cap 21 is fitted to the rotary shaft 15, the line segment connecting the pair of screw holes to which the bolt 34 is screwed is used as a mark so that the cap 21 matches the line segment. Is fitted to the rotary shaft 15. This may be implemented by replacing the pair of screw holes with a pair of marks on the casing 10a around the other shaft end of the rotary shaft 15.

  In this case, when the Hall IC 40 is fixed to the housing 10a with a bolt 34, a line connecting one pair of Hall elements 41A formed on the semiconductor substrate SUB with respect to a line segment connecting the pair of marks. Or the line segment connecting the other set of Hall elements 41B to be aligned with the case 31 as viewed from the Z direction.

In the above embodiment, the magnet MG is attached to the rotating shaft 15 via the cap 21. This may be performed by omitting the cap 21 and directly attaching the magnet MG.
In the above embodiment, the magnet side mark groove 25 as a mark is formed in the magnet MG. This may be carried out by providing marks such as protrusions, grooves, marks, etc. for indicating the magnetic pole direction only on the cap 21.

  In this case, the magnet MG attached to the cap 21 is an isotropic magnet and is a magnetic body that is not magnetized before being attached to the cap 21. And after attaching to the cap 21, the magnetic body is magnetized according to a mark and the magnet MG is formed.

  Therefore, the detection surface 40a of the Hall IC 40 can be easily viewed while looking at the mark formed on the cap 21 so that the detection directions of the X-direction component Bx and the Y-direction component By of the external magnetic field coincide with the direction of the magnetic pole of the magnet MG. The Hall IC 40 can be disposed relative to the magnet MG.

  DESCRIPTION OF SYMBOLS 10 ... Rotary valve apparatus, 10a ... Housing | casing, 15 ... Rotating shaft, 20 ... Rotation angle detection apparatus, 21 ... Cap, 22 ... Cover part, 24 ... Cap side mark groove (mark), 25 ... Magnet side mark groove (mark) , 31 ... Case, 32 ... Support protrusion (connecting part), 33 ... Shaft hole (connecting part), 34 ... Bolt (connecting part), 40 ... Hall IC, 40a ... Detection surface, 41, 41A, 41B ... Hall element 42 ... magnetic collecting film, T ... external terminal, V ... output voltage, An ... N magnetic pole region, As ... S magnetic pole region, C1 ... center axis, K0, K1, K2, K3 ... characteristic line, L1 ... boundary line, MG ... Magnet, P1, P2, P3 ... Center point, Sa ... Substrate surface, PWA ... Printed circuit board, SUB ... Semiconductor substrate, RB1-RB4 ... First to fourth rotary valves.

Claims (6)

The magnet is rotated on a detection surface of the Hall IC on a plane parallel to the detection surface, and the Hall IC and the center of the Hall IC are aligned so that the central axis of the rotation center of the magnet coincides with the central axis of the detection surface of the Hall IC. Magnets are arranged relatively, and the direction of the magnetic field of the rotating magnet is detected by the Hall IC as a first orthogonal component and a second orthogonal component orthogonal to each other, and from the ratio of the first orthogonal component and the second orthogonal component A rotation angle detection device for detecting a rotation angle of the magnet as a magnetic field vector,
A mark indicating the magnetic pole direction of the NS pole is provided on the magnet,
Set the magnetic pole direction of the magnet to the first specific rotation angle position,
The magnetic pole direction of the NS pole of the mark that the detection direction of the first orthogonal component or the detection direction of the second orthogonal component of the detection surface is provided on the magnet with respect to the magnet at the set position. The detection direction of the Hall IC is shifted by the specific rotation angle relative to the magnetic pole direction of the magnet at the second specific rotation angle position rotated by the specific rotation angle of the first specific rotation angle position with respect to A rotation angle detection device characterized by that. The rotation angle detection device according to claim 1,
The magnet is attached to the outer surface of the lid portion of the covered cylindrical cap attached to the shaft end portion on the rotation shaft rotatably supported by the housing,
The housing is provided with an index for alignment of the mark formed on the magnet,
The Hall IC is housed in a case fixed to the housing,
When the case is fixed to the housing, the detection direction of one of the detection surfaces of the Hall IC is at the first specific rotation angle position with respect to the magnetic pole direction of the NS pole of the mark provided on the magnet. A connecting portion that is connected to the housing so that the center point of the detection surface and the center point of the magnet coincide with each other in the direction of the second specific rotation angle position rotated by a specific rotation angle. A rotation angle detecting device provided. In the rotation angle detection device according to claim 2,
The rotation angle detection device characterized in that the index for positioning the magnet provided in the casing is a screw hole that is screwed to a bolt of a connecting portion that is connected to the casing provided in the case. . In the rotation angle detection device according to any one of claims 1 to 3,
The magnet is a disk-shaped magnet, and the center point is perpendicular to the N pole area of the N pole on one side and the S pole area of the S pole on the other side. A rotation angle detection device characterized by being formed. In the rotation angle detection device according to claim 3 or 4,
Two cap-side marks facing each other across the center point are formed on the outer peripheral edge of the lid outer surface,
2. A rotation angle detecting device according to claim 1, wherein the magnet-side marks formed at two locations of the magnet have an interval between the marks coincided with an interval between the cap-side marks. The magnet is rotated on a detection surface of the Hall IC on a plane parallel to the detection surface, and the Hall IC and the center of the Hall IC are aligned so that the central axis of the rotation center of the magnet coincides with the central axis of the detection surface of the Hall IC. Magnets are arranged relatively, and the direction of the magnetic field of the rotating magnet is detected by the Hall IC as a first orthogonal component and a second orthogonal component orthogonal to each other, and from the ratio of the first orthogonal component and the second orthogonal component A rotation angle detection device for detecting a rotation angle of the magnet as a magnetic field vector,
The magnet is attached to the outer surface of the lid portion of the covered cylindrical cap attached to the shaft end portion on the rotation shaft rotatably supported by the housing,
A mark indicating the magnetic pole direction of the NS pole of the magnet is provided on the cap,
The cap is set to the first specific rotation angle position of the magnetic pole direction of the magnet,
The magnetic pole direction of the NS pole of the mark provided on the cap with the detection direction of the first orthogonal component or the detection direction of the second orthogonal component of the detection surface on the detection surface with respect to the magnet at the set position The detection direction of the Hall IC is shifted by the specific rotation angle relative to the magnetic pole direction of the magnet at the second specific rotation angle position rotated by the specific rotation angle of the first specific rotation angle position with respect to A rotation angle detection device characterized by that.

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