JP2000074614A - Rotational angle sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotational angle sensor which can have its assembling process shortened and its component management in the assembling process simplified. SOLUTION: A throttle sensor 10 is equipped with a 1st housing 20, a 2nd housing 40, and a rotor 30 supported rotatably in the 1st housing 20. A magnet structure 320 which constitutes part of the rotor 30 is equipped with a permanent magnet 322 and a couple of yokes 324 and 326 fixed to the permanent magnet 322. The 2nd housing 40 is provided with a cover part 402 sealing the 1st space 204 of the 1st housing 20 and a substrate part 410 where the Hall element 430 is mounted by molding them in one body. The Hall element 430 mounted on the substrate part 410 is inserted into and arranged between the magnetic pole surfaces 334 and 336 of the yokes 324 and 326 together with the substrate part 410.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation angle sensor for detecting a rotation angle of a rotating body, and more particularly, to a throttle sensor for detecting an opening of a throttle valve provided in, for example, an intake passage of an internal combustion engine. As a rotation angle sensor.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open Nos. Hei 7-260412, Hei 7-260413 and Hei 7-280 disclose rotational angle sensors used for throttle sensors and the like.
A “rotational position sensor” described in, for example, Japanese Patent Application Publication No. 509 is known.

FIG. 6 is a sectional view showing a rotation position sensor 900 of this type. The rotational position sensor 900 includes a magnet structure 910 and a Hall effect device 920 that detects the density of magnetic flux generated by the magnet structure 910.
The magnet structure 910 is fixed to a rotor 940 rotatably supported by the housing 930.
And rotate together. The rotor 940 is engaged with a valve shaft of a throttle valve (the axis of which is indicated by “C”), and rotates together with the valve shaft.

The magnet structure 910 is composed of a magnetically permeable pole piece 950 having a substantially C-shaped cross section and a pair of magnets 960 and 970 fixed to opposing portions of the magnetically permeable pole piece 950. Opposing magnetic pole surfaces 960a, 970a of these magnets 960, 970 have a shape that extends helically inclining with respect to the axial direction of the valve shaft.

The housing 930 includes magnets 960 and 97 respectively.
The substrate 980 is fixed in a state inserted between the magnets 960 and 970 on the substrate 980. The Hall effect device 920 is mounted on the upper surface of a portion of the substrate 980 located between the magnets 960 and 970.

A cover 934 is fitted into the opening 932 of the housing 930, and the magnet structure 910 and the substrate 9
The inner space of the housing 930 where the 80 is disposed is sealed by the cover 934.

In such a rotational position sensor 900, when the rotor 940 rotates together with the valve shaft, the size of the gap between the magnets 960 and 970 at the position of the Hall effect device 920 changes, and the magnetic flux passing through the Hall effect device 920 changes. Since the density changes, the rotation angle of the valve shaft, that is, the opening of the throttle valve can be detected from the magnitude of the magnetic flux density.

[0008]

When manufacturing such a rotational position sensor 900, a substrate 980 on which a Hall effect device 920 is mounted is assembled to a housing 930, and then a cover 934 is attached to the housing 930.
It was necessary to sequentially perform two assembling steps, such as assembling. In addition, before each of these assembling steps, since the board 980 and the cover 934 exist as individual components in addition to the housing 930, it is necessary to manage these components. Therefore, in the conventional configuration, even if such an assembling process is shortened, there is naturally a limit, and parts management in the assembling process is also complicated.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a rotation angle sensor capable of shortening the assembly process and simplifying component management in the assembly process. To provide.

[0010]

Means for Solving the Problems In order to achieve the above object, an invention according to claim 1 is a pair of opposing portions which rotate together with a rotating body and face each other at a predetermined interval in the direction of the rotation axis of the rotating body. A magnet structure having a magnet structure, a magnetic detection element mounted on the substrate and disposed between the facing portion together with the substrate, and a housing in which the magnet structure and the magnetic detection element are disposed. The structure constitutes a closed magnetic path for magnetic flux passing through the magnetic sensing element, and the magnet structure is rotated together with the rotating body to change the distance between the opposing portions at the position of the magnetic sensing element, thereby passing through the magnetic sensing element. In a rotation angle sensor that changes a magnetic flux density and detects a rotation angle of a rotating body based on the magnitude of the magnetic flux density, a first housing in which a magnet structure is rotatably supported by a housing. Constituted by a second housing assembled to ring and said first housing, and so as to integrally mold the cover portion and the substrate for sealing the first housing to the second housing.

According to this structure, when assembling the second housing to the first housing, the operation of sealing the inside of the first housing with the cover portion and disposing the substrate between the opposing portions to detect the magnetic field. The operation of arranging the element at a predetermined position can be performed in parallel. Also,
Since the cover and the substrate are integrally molded with the second housing, it is not necessary to manage these parts as individual parts.

According to a second aspect of the present invention, in the rotation angle sensor according to the first aspect, the cover and the first housing form a joint surface that is joined to each other in a state of being inclined with respect to the rotation axis direction of the rotating body. I have it.

According to this configuration, while the substrate is inserted between the opposing portions so as to arrange the magnetic sensing element at a predetermined position, the joining surface of the cover portion is joined to the joining surface on the first housing side to form the first housing. The inside of the housing can be sealed.

According to a third aspect of the present invention, in the rotation angle sensor according to the first aspect, the substrate is formed integrally with the second housing such that a mounting surface on which the magnetic detecting element is mounted is exposed. It is said that.

According to such a configuration, the work of arranging the wiring pattern on the mounting surface of the substrate and the work of mounting the magnetic sensing element on the mounting surface can be easily performed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied as a throttle sensor for detecting the opening (throttle opening) of a throttle valve provided in an intake pipe of an engine will be described below.

FIG. 1 is a sectional view of a throttle sensor 10 according to the present embodiment. The throttle sensor 10 includes a first housing 20 fixed to an intake pipe (not shown),
A second housing 40 assembled to the first housing 20; and a rotor 30 rotatably provided in the internal space formed by the housings 20 and 40 (the rotation axis C is shown in FIG. 1). It has.

The first housing 20 is formed in a shape having an internal space by a resin material such as PBT (polybutylene terephthalate) resin, and the internal space is divided into a first space 204 and a second space 206 by a partition wall portion 202. Is divided into A substantially cylindrical bearing 208 made of a metal material such as copper is fixed to the partition 202.

The rotor 30 has a shaft 302 rotatably supported by bearings 208 such that each end is located in a first space 204 and a second space 206, respectively.
, A magnet structure 320 as a magnetic path component disposed in the first space 204, and a lever 308 disposed in the second space 206.

A disk 302 is provided at one end of the shaft 302.
a is formed, and the magnet structure 320 is
02a so as to be integrally rotatable. Shaft 30
A plate 306 that regulates the movement of the shaft 302 in the axial direction is fitted to the other end of the lever 2, and the lever 308 is fixed to the shaft 302 via the plate 306 so as to be integrally rotatable. The shaft 302 and the plate 306 are formed of a non-magnetic material such as austenitic stainless steel.

The spring 12 is provided between the lever 308 and the partition wall 202, and the lever 308 is constantly urged in the circumferential direction of the rotation axis C by the urging force of the spring 12. The lever 308 is engaged with another lever provided so as to be integrally rotatable on a valve shaft (not shown) of the throttle valve. By this engagement,
When the valve shaft rotates in the direction in which the throttle valve opens, the rotor 30 rotates around the rotation axis C against the urging force of the spring 12.

The magnet structure 320 is connected to the rotation axis C of the rotor 30.
And a quadrangular prism-shaped permanent magnet 322 arranged substantially coaxially with
A pair of yokes 324 and 326 fixed to the permanent magnet 322 so as to be integrally rotatable;
26 is fixed to a permanent magnet 322. The permanent magnet 322 is made of a rare earth material, and the yokes 324 and 326 are made of a material having high magnetic permeability such as iron and steel. The connecting portion 304 is formed of a resin material such as PPS (polyphenylene sulfide) resin.

FIG. 2 is a front view of the magnet structure 320.
FIG. 3 is a perspective view of the magnet structure 320 (the connection portion 304 is not shown in each of these drawings). The yokes 324 and 326 are formed substantially in the shape of a fan, and the rotation axes C
Are arranged so as to face each other at a predetermined interval in the axial direction. In the yokes 324 and 326, rectangular cutouts 324a and 326a are formed in portions where the rotation axis C passes. These notches 324a, 32
Each end of the permanent magnet 322 is fitted to 6a, and both end surfaces 322a, 32a of the permanent magnet 322 in the axial direction are fitted.
2b is exposed from the yokes 324 and 326. The yokes 324, 32
6 and the permanent magnet 322 are integrally fixed by a connecting portion 304.

Arc-shaped magnetic pole surfaces 334 and 336 are formed on the peripheral portions of the yokes 324 and 326 so as to extend in the circumferential direction of the rotation axis C and to face each other at predetermined intervals in the axial direction of the rotation axis C. . As shown in FIG. 2, one of the magnetic pole surfaces 334 and 336 has a shape that extends in a spiral shape while being inclined with respect to the axial direction of the rotation axis C. Therefore, the size of the gap H between the magnetic pole surfaces 334 and 336 changes continuously in the circumferential direction of the rotation axis C.

The magnetic flux generated by the permanent magnet 322 passes through the inside of each of the yokes 324 and 326, so that the inside of the magnet structure 320 has a closed magnetic path of the magnetic flux as shown by a two-dot chain line in FIGS. Is formed. Each pole face 3
The magnitude of the magnetic flux density between the magnetic pole surfaces 34 and 336 changes in accordance with the size of the gap H between the magnetic pole surfaces 334 and 336, and the smaller the gap H is, the smaller the gap H is. .

As shown in FIG. 1, the second housing 40
Is extended so as to be positioned between the magnetic pole surfaces 334 and 336, and a cover portion 402 for covering the inside of the first housing 20 so as to hermetically seal the first housing 20, and a connector portion 404 provided with a plurality of terminals 406. A rectangular plate-shaped substrate portion 410 on which the hall element 430 and the like are mounted. The cover section 402, the connector section 404, and the board section 410 are integrally formed of a resin material such as PBT resin similarly to the first housing 20.

As shown in FIG. 1 and FIG.
The joining surface 408 inclined with respect to the rotation axis C
An annular joint 408 having a is formed. First
An annular joint 210 is formed in the housing 20 corresponding to the joint 408. This joint 2
10 has a circumferential groove 210a extending in the circumferential direction thereof, and a seal ring 212 made of a rubber material is provided in the circumferential groove 210a. The surface of the seal ring 212 exposed from the circumferential groove 210a is connected to the first joint surface 408a that is inclined with respect to the rotation axis C.
Of the housing 20 side. The joining surface 4 of the cover 402 and the first housing 20
08a and 212a exist in a plane inclined with respect to the rotation axis C.

The first joint 408a and the joint 212a are located on the periphery of the cover 402 in a state where the joints 408a and 212a are joined.
A part of the peripheral wall 214 of the housing 20 is heat caulked toward the rotation axis C side, so that the first housing 20
The second housing 40 is mounted on the second housing 40. By assembling the two housings 20 and 40 in this manner, the first space 204 is a closed space closed by the inner wall surface of the cover 402.

As shown in FIG. 1, a concave portion 412 is formed at a position opposed to one magnetic pole surface 336 at a front end portion between the magnetic pole surfaces 334 and 336 of the substrate portion 410. Inside each pole face 334,336
A substantially rectangular parallelepiped Hall element 430 is mounted so as to be located between the two. The Hall element 430 is the same as the element 430.
Is a magnetic detection element that outputs a signal (Hall voltage) according to the strength (magnetic flux density) of the magnetic flux applied to the. Board part 41
At 0, the mounting surface on which the Hall element 430 is mounted is exposed without being covered by the cover 402 or the like.

As shown in FIG. 5, the second housing 40
At the base end portion of the substrate portion 410 (the right portion in FIG. 1)
Is formed with another recess 460 so as to be adjacent to the recess 412 in which the Hall element 430 is mounted. An IC 450 constituting a drive circuit for supplying a drive current to the Hall element 430, a temperature characteristic compensation circuit for compensating for the temperature characteristic of the Hall element 430, and the like are mounted in the recess 460. This IC 450 is a bare chip type IC having no resin package. These Hall elements 4
30, the IC 450, and the terminal 406 are connected to the substrate unit 41.
The connection is made by a plurality of wiring patterns 452 formed at zero.

Each of the recesses 412 and 460 is filled and hardened with a resin potting material, and the Hall element 430 and the IC 450 are covered with the resin potting material. This resin potting material is a Hall element 430,
In addition to preventing moisture from adhering to the IC 450 and its vicinity, each of the elements 430 and 450 is connected to each of the recesses 41.
2,460.

The throttle sensor 1 constructed as described above
At 0, when the rotor 30 rotates around the rotation axis C in accordance with the opening / closing operation of the throttle valve, the size of the gap H between the magnetic pole surfaces 334 and 336 sandwiching the Hall element 430 changes according to the rotation angle. The density of the magnetic flux passing through the Hall element 430 changes. As a result, the Hall element 430
Generates a Hall voltage corresponding to the magnitude of this magnetic flux density, in other words, the throttle opening. The Hall voltage is input to the IC 450 and subjected to various processes such as temperature characteristic compensation, and then output as an opening signal (voltage signal) having a correlation with the throttle opening to the engine control device via the terminal 406. Is done.

As described above, in the throttle sensor 10 according to the present embodiment, the housing containing the magnet structure 320 and the like is divided into the first housing 20 and the second housing 40, and the second housing 40 Further, a cover 402 for sealing the inside of the first housing 20 and a substrate 410 on which the Hall element 430 and the like are mounted are integrally formed.

(1) Therefore, according to the present embodiment, the second
When assembling the housing 40 to the first housing 20, the work of sealing the inside of the first housing 20 with the cover portion 402, and disposing the substrate portion 410 between the magnetic pole surfaces 334 and 336 to fix the Hall element 430 to a predetermined position The work of arranging at the position can be performed in parallel, and it is not necessary to manage the cover 402 and the substrate 410 as a single component. As a result, the assembling process can be shortened, and parts management in the assembling process can be simplified.

(2) Further, in this embodiment, the cover 4
02 and the first housing 20 have a joining portion 4 having joining surfaces 408a and 212a inclined with respect to the rotation axis C of the rotor 30, ie, the axis of the valve shaft of the throttle valve.
08, 210 are formed. Therefore, while the substrate unit 410 is inserted between the magnetic pole surfaces 334 and 336 to arrange the Hall element 430 at a predetermined position, the cover unit 40
The second joint surface 408a is joined to the joint surface 212a on the first housing 20 side to seal the inside of the first housing 20. As a result, workability when assembling the second housing 40 to the first housing 20 can be improved.

(3) In this embodiment, the cover 4
02 and the joint surfaces 408a, 21 of the first housing 20
2a are all present in a plane inclined with respect to the rotation axis C, so that a part of the peripheral wall 214 of the first housing 20 is heat-sealed to move the second housing 40 to the first housing 20.
By pressing against the housing 20 side, the surface pressure between the joining surfaces 408a and 212a can be made substantially uniform. Accordingly, a high sealing property can be ensured at the joint portion, and the inside of the first housing 20 can be more reliably sealed, and the reliability of the throttle sensor 10 can be improved.

(4) Further, in this embodiment, the housing is divided into the first housing 20 and the second housing 40, but the second housing 40 has the cover 4
02 is integrally formed, and a portion of the second housing 40 that contacts the first housing 20 is limited to the cover portion 402. Therefore, the number of seal portions in the throttle sensor 10 does not increase with the division of the housing, and the throttle sensor 10
It does not lower the airtightness inside.

(5) In this embodiment, the Hall element 4
The mounting surface of the substrate portion 410 on which the 30 and the like are mounted is covered with the cover portion 4.
02 and the like without being covered. Therefore, the wiring pattern 45 is mounted on the mounting surface of the substrate 410.
2 and the operation of mounting the Hall element 430 and the IC 450 on the mounting surface can be easily performed.
The workability can be improved.

(6) Further, in this embodiment, since the board portion 410 is formed integrally with the second housing 40, there is no assembly error when the board is assembled to the housing. Each pole face 334, 3
The position of the Hall element 430 between 36 is not shifted. Therefore, it is possible to eliminate variations in sensor characteristics due to such a displacement of the Hall element 430.

Although the embodiment embodying the present invention has been described above, this embodiment can be implemented by changing the configuration as follows. In the above-described embodiment, by heat caulking a part of the peripheral wall 214 of the first housing 20, the two housings 20,
40 is assembled. For example, a claw portion and an engagement concave portion are formed on the housings 20 and 40 by tightening and fixing using, for example, bolts or the like.
The housings 20 and 40 may be assembled by engaging the claw and the recess.

In the above embodiment, both housings 20, 4
Although the zero joining surfaces 408a and 412a exist in one plane inclined with respect to the rotation axis C, the joining surfaces 408a and 412a may be planes perpendicular to the rotation axis C. Further, the joint surfaces 408a and 412a may be configured by a plurality of flat surfaces or curved surfaces.

In the above embodiment, the Hall element 430 is used as the magnetic detection element. However, for example, a magnetoresistive element can be used. In the above embodiment, the present invention is applied to the throttle sensor that detects the throttle opening from the rotation position of the valve shaft of the throttle valve.For example, an accelerator sensor that detects the amount of depression of the accelerator pedal, The present invention can also be applied to a sensor that detects a rotation angle.

[0043]

According to the first aspect of the present invention, the first
When assembling the second housing to the first housing, the operation of sealing the inside of the first housing with the cover portion and the operation of arranging the magnetic sensing element at a predetermined position by disposing the substrate between the opposing portions are performed in parallel. Then you can do it. In addition, since the cover and the substrate are formed integrally with the second housing, it is not necessary to manage these parts as individual parts. As a result, the assembling process can be shortened, and parts management in the assembling process can be simplified.

According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, in addition to inserting the substrate between the opposing portions so as to dispose the magnetic detection element at a predetermined position, Since the joining surface can be joined to the joining surface on the first housing side to seal the inside of the first housing, workability when assembling the second housing to the first housing can be improved. Can be.

According to the third aspect of the present invention, in addition to the effects of the first or second aspect of the present invention, the work of arranging the wiring pattern on the mounting surface of the substrate and the magnetic detection on the mounting surface can be achieved. The work of mounting the element can be easily performed, and the workability can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a throttle sensor.

FIG. 2 is a front view of the magnet structure.

FIG. 3 is a perspective view of a magnet structure.

FIG. 4 is a perspective view showing an assembled state of a housing.

FIG. 5 is an enlarged cross-sectional view showing a substrate unit.

FIG. 6 is a sectional view of a conventional rotation position sensor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Throttle sensor, 12 ... Spring, 20 ... 1st housing, 40 ... 2nd housing, 30 ... Rotor, 202 ... Partition part, 204 ... 1st space, 206 ... 2nd
Space, 208: bearing, 210: joint, 210a
... peripheral groove, 212 ... seal ring, 212a ... joining surface, 3
02: shaft, 302a: disk part, 304: connecting part,
306: plate, 308: lever, 320: magnet structure, 322: permanent magnet, 322a, 322b: end face, 3
24, 326: yoke, 324a, 326a: notch,
334, 336: magnetic pole surface, 402: cover part, 404 ...
Connector part, 406 terminal, 408 joint part, 4
08a: bonding surface, 410: substrate portion, 430: Hall element, 412: concave portion, 450: IC, 460: concave portion, H:
Gap, C ... rotating shaft.

Continued on the front page F term (reference) 2F063 AA35 BA06 CB01 CC01 DB07 GA53 GA61 GA79 GA80 ZA01 2F077 AA46 AA49 JJ01 JJ08 JJ09 JJ21 UU03 VV02 VV10 VV11 VV31 3G065 CA00 HA22 3G084 DA00 FA10

Claims (3)

[Claims] 1. A magnet structure having a pair of opposing portions that rotate with a rotating body and oppose at a predetermined interval in a direction of a rotation axis of the rotating body, and a magnet structure mounted on a substrate and the opposing portion together with the substrate. And a housing in which the magnet structure and the magnetic detection element are disposed.The magnet structure constitutes a closed magnetic path for magnetic flux passing through the magnetic detection element. By rotating the magnet structure together with the rotating body to change the distance between the facing portions at the position of the magnetic detection element,
In a rotation angle sensor configured to detect a rotation angle of the rotating body based on a magnitude of the magnetic flux density by changing a density of a magnetic flux passing through the magnetic detection element, the magnet structure can rotate the housing. A first housing supported by the first housing and a second housing assembled to the first housing; a cover portion for sealing the inside of the first housing and the substrate are integrally formed on the second housing; A rotation angle sensor, characterized in that: 2. The rotation angle sensor according to claim 1, wherein the cover portion and the first housing have a joint surface that is joined to each other while being inclined with respect to a rotation axis direction of the rotating body. 3. The device according to claim 1, wherein the substrate is formed integrally with the second housing such that a mounting surface on which the magnetic detection element is mounted is exposed. Rotation angle sensor.