WO2013008277A1

WO2013008277A1 - Position detection device

Info

Publication number: WO2013008277A1
Application number: PCT/JP2011/004007
Authority: WO
Inventors: 吉澤　敏行; 秀哲有田; 波多野　健太
Original assignee: 三菱電機株式会社
Priority date: 2011-07-13
Filing date: 2011-07-13
Publication date: 2013-01-17
Also published as: JP5683703B2; JPWO2013008277A1

Abstract

By making a surface facing a magnetic field generating body (30) in a first fixed magnetic body (10) a combination of a curved line (11) and two straight line portions (12, 13), and making a surface facing the magnetic field generating body (30) in a second fixed magnetic body (20) a straight line section (21), positioning can be accurately and easily carried out during manufacture and assembly by using the facing straight line sections (12, 21) and the straight line sections (13, 21). Furthermore, the magnetic field generating body (30) can be moved in a stable manner along the straight line section (21) of the second fixed magnetic body (20).

Description

Position detection device

The present invention relates to a position detection device that detects a moving position of an object that moves linearly.

A conventional position detection device is disclosed in, for example, Patent Document 1. FIG. 24 is a front view showing a configuration of a conventional position detection apparatus. The position detection device includes a first fixed magnetic body (magnetic flux guide member) 91, a second fixed magnetic body (magnetic flux guide member) 92, a magnetic field generator (magnet) 93, and a magnetic sensor (magnetoelectric conversion element) 94. Has been. The magnetic field generator 93 linearly moves between the opposing surfaces of the first fixed magnetic body 91 and the second fixed magnetic body 92 (in the direction indicated by the arrow X in FIG. 24), and these first fixed magnetic bodies 91 are moved. The opposing inner surfaces of the second fixed magnetic body 92 have a curved shape. The inner surfaces of the first fixed magnetic body 91 and the second fixed magnetic body 92 are curved so that the distance between the magnetic field generator 93 and the first and second fixed magnetic bodies 91 and 92 (see FIG. 24). (Indicated by an arrow Y) changes according to the movable position of the magnetic field generator 93. By changing this distance (positional relationship), the magnetic flux density passing through the magnetic sensor 94 changes according to the movable position of the magnetic field generator 93. The amount of change in the magnetic flux density is detected by the magnetic sensor 94 and converted into an electric signal. Since this electric signal is a signal having a linear relationship with the position of the magnetic field generator 93, position information of the magnetic field generator 93 can be detected from the output signal of the magnetic sensor 94.

JP-T-2005-515459

In the position detection device having such a configuration, the distance between the magnetic field generator 93 and the first and second fixed

magnetic bodies

91 and 92 is important for the accuracy of position information detection. Therefore, the positional relationship of each part becomes important in manufacturing. However, since the magnetic field generator 93 is sandwiched between the curved surfaces of the first and second fixed

magnetic bodies

91 and 92, the curved surface and the magnetic field of the first and second fixed

magnetic bodies

91 and 92 are configured. There existed a subject that it was difficult to position the distance with the generator 93 correctly.

Further, a magnetic attractive force acts between the magnetic field generator 93 and the first and second fixed

magnetic bodies

91 and 92. If the magnetic field generator 93 moves in the middle of the first and second fixed

magnetic bodies

91 and 92, the magnetic attractive force is balanced, but the magnetic field generator 93 is either of the first and second fixed

magnetic bodies

91 and 92. When the heel distance is short, the magnetic attractive force attracted to the fixed magnetic body on the near side works, and the magnetic field generator 93 cannot move stably. Further, it is necessary to provide vibration resistance so that the distance between the magnetic field generator 93 and the first and second fixed

magnetic bodies

91 and 92 does not change with respect to external vibration.
In addition, the magnetic field generator 93 and the first and second fixed

magnetic bodies

91 and 92 are moved while maintaining the same distance, and the magnetic field generator 93 is also resistant to external vibration. Is required to be provided on the outer side of the first and second fixed

magnetic bodies

91 and 92 in order to move them stably.
As described above, there is a problem that the position detection device becomes large by providing the vibration-proof mechanism and the guide mechanism.

The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain a position detection device that facilitates assembly. It is another object of the present invention to obtain a position detection device that can secure a stable movement of a magnetic field generator and can be miniaturized.

The position detection device according to the present invention has an N-polar polarity surface and an S-polarity surface on the back side thereof, and is attached to a reciprocating drive shaft and moves in a direction perpendicular to the magnetic pole direction in which the NS poles are arranged. A generator, a first fixed magnetic body disposed opposite to one polar surface of the magnetic field generator, and a second fixed magnetic body disposed opposite to the other polar surface of the magnetic field generator; And a magnetic sensor for detecting a magnetic flux passing therethrough, the first fixed magnetic body having a polarity of one polarity. The magnetic sensor is disposed between the opposing surfaces of the first fixed magnetic body and the second fixed magnetic body. The surface facing the surface has a curved portion and two straight portions parallel to the moving direction of the magnetic field generator. The second fixed magnetic body has a surface facing the other polar surface parallel to the moving direction. The magnetic sensor includes a magnetic field generator and a first fixed magnetic field according to the reciprocating motion of the drive shaft. Distance pole direction between the body that changes, in which to detect the position of the magnetic field generator since the magnetic flux passing through changes.

According to the present invention, the magnetic field generator facing surface of the first fixed magnetic body is a combination of a curved portion and a linear portion, and the magnetic field generator facing surface of the second fixed magnetic body is a linear portion, thereby producing and assembling. Sometimes, the first and second fixed magnetic bodies can be easily positioned using the opposing linear portions. Thereby, the positioning accuracy between the components can be improved, and the accuracy of the output detection linearity (linearity) can be improved. In addition, by setting the second fixed magnetic body facing surface of the magnetic field generator as a straight portion, this straight portion can be used as a movable guide or sliding surface of the magnetic field generator, so that the magnetic field generator can be moved stably. Therefore, there is no need to provide a guide outside. Therefore, the position detection device can be reduced in size.

It is a front view which shows the basic composition of the position detection apparatus which concerns on Embodiment 1 of this invention. 5 is a front view for explaining a positioning method of the position detection device according to Embodiment 1. FIG. It is a front view which shows another example of the position detection apparatus which concerns on Embodiment 1. FIG. It is an external appearance perspective view which shows the example of an assembly | attachment with the position detection apparatus which concerns on Embodiment 1, and another apparatus. It is an external appearance perspective view which shows another example of the assembly | attachment with the position detection apparatus which concerns on Embodiment 1, and another apparatus. It is a front view which shows the basic composition of the position detection apparatus which concerns on Embodiment 2 of this invention. It is a front view which shows the modification of the position detection apparatus which concerns on Embodiment 2. FIG. FIG. 10 is a front view showing another modification of the position detection device according to the second embodiment. FIG. 10 is a front view showing another modification of the position detection device according to the second embodiment. FIG. 10 is a front view showing another modification of the position detection device according to the second embodiment. It is a front view which shows the basic composition of the position detection apparatus which concerns on Embodiment 3 of this invention. It is a graph showing the relationship of the input signal to the magnetic sensor according to the position of a magnetic field generator. 12A shows a position detection apparatus that measures the graph shown in FIG. 12A. FIG. 12B (a) shows a case where no step is provided, and FIGS. 12B (b) and (c) show a case where a step is provided. FIG. 10 is a front view showing a modification of the position detection device according to the third embodiment. It is an external appearance perspective view which shows the basic composition of the position detection apparatus which concerns on Embodiment 4 of this invention. FIG. 15A is a plan view and FIG. 15B is a front view of a basic configuration of a position detection device according to Embodiment 4 of the present invention. It is a front view which shows the basic composition of the position detection apparatus which concerns on Embodiment 5 of this invention. FIG. 10 is an external perspective view in which a first fixed magnetic body and a second fixed magnetic body constituting a position detection device according to Embodiment 5 are integrated. FIG. 18A is a front view, and FIG. 18B and FIG. 18C are external perspective views, illustrating another example of a connecting portion that constitutes the position detection device according to the fifth embodiment. It is a top view which shows the basic composition of the position detection apparatus which concerns on Embodiment 7 of this invention. It is a longitudinal cross-sectional view of the actuator carrying the position detection apparatus based on Embodiment 8 of this invention. FIG. 16 is a longitudinal sectional view showing another example of an actuator equipped with the position detection device according to the eighth embodiment. It is sectional drawing which cut | disconnected the position detection apparatus which concerns on Embodiment 8 along the AA line of FIG. It is the figure which looked at the position detection apparatus which concerns on Embodiment 8 from the arrow B direction of FIG. It is a front view which shows the basic composition of the conventional position detection apparatus.

Hereinafter, in order to explain the present invention in more detail, modes for carrying out the present invention will be described with reference to the accompanying drawings.
Embodiment 1 FIG.
FIG. 1 shows a basic configuration diagram of a position detection apparatus according to Embodiment 1 of the present invention, in which a first fixed magnetic body 10 and a second fixed magnetic body 20 that become a stator, a magnetic field generator 30 and The magnetic sensor 40 is provided.

The magnetic field generator 30 includes surfaces having both N and S polarities, and the magnetic field generator 30 is orthogonal to the direction in which the N and S poles are arranged (hereinafter referred to as the magnetic pole direction Y) (hereinafter referred to as the magnetic pole direction Y). , Move in the moving direction X). The first fixed magnetic body 10 is disposed opposite to one polar face of the magnetic field generator 30, and the second fixed magnetic body 20 is disposed opposite to the other polar face of the magnetic field generator 30. Yes.
Although FIG. 1 shows an example in which the first fixed magnetic body 10 is disposed on the N pole side and the second fixed magnetic body 20 is disposed on the S pole side, the polarities may be reversed. Although not shown, the magnetic field generator 30 is attached to an actuator shaft (drive shaft) or the like, and the shaft reciprocates (moves linearly) in the movement direction X so that it is integrated with the shaft. The magnetic field generator 30 also moves in the movement direction X.

The surface of the first fixed magnetic body 10 facing the magnetic field generator 30 is composed of a curved portion 11 and two

straight portions

12 and 13. In the example of FIG. 1, the

straight portions

12 and 13 are formed at both end portions of the moving range of the magnetic field generator 30, and the curved portion 11 is formed between the

straight portions

12 and 13. The curved portion 11 may not be a smooth curved shape, but may be a polygonal shape including a large number of straight lines. The

straight portions

12 and 13 have a straight shape parallel to the moving direction X of the magnetic field generator 30.
On the other hand, the surface of the second fixed magnetic body 20 on the side facing the magnetic field generator 30 (the surface facing the first fixed magnetic body 10 described above) is a linear portion 21 parallel to the moving direction X of the magnetic field generator 30. It consists of Accordingly, the magnetic field generator 30 has a certain distance from the straight portion 21 of the second fixed magnetic body 20 in the gap formed by the opposing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20. It will move while keeping.

In FIG. 1, the magnetic field generator 30 is in a state where the magnetic field generator 30 and the first fixed magnetic body 10 and the magnetic field generator 30 and the second fixed magnetic body 20 are separated from each other. The fixed magnetic body 10 and the second fixed magnetic body 20 are moved without being in contact with each other, but the present invention is not limited to this. For example, the magnetic field generator 30 and the linear portion 21 of the second fixed magnetic body 20 may be in contact with each other, and the magnetic field generator 30 may slide on the linear portion 21. Further, for example, the linear portion 21 of the second fixed magnetic body 20 is covered with a resin so that the second fixed magnetic body 20 and the magnetic field generator 30 are separated from each other, and the magnetic field generator 30 is formed on the resin surface. May be configured to slide. On the contrary, the magnetic field generator 30 may be covered with resin so that the resin surface of the magnetic field generator 30 slides on the straight portion 21 of the second fixed magnetic body 20. Of course, both the linear portion 21 of the second fixed magnetic body 20 and the magnetic field generator 30 may be covered with resin. Further, for example, a guide extending in the movement direction X may be provided outside the gap portion, and the magnetic field generator 30 may be moved along the guide.

Further, a magnetic sensor 40 is disposed between the first fixed magnetic body 10 and the second fixed magnetic body 20, and a lead wire (electrode terminal) 41 is exposed to the outside. In the example of FIG. 1, the magnetic sensor 40 is installed between the linear portion 12 of the first fixed magnetic body 10 and the linear portion 21 of the second fixed magnetic body 20. In addition, a magnetic sensor 40 is disposed on an extension line in the moving direction X of the magnetic field generator 30 in the gap formed by the opposing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20. In this structure, the magnetic sensors 40 are arranged in a straight line.

The lines of magnetic force emitted from the N pole of the magnetic field generator 30 pass through the first fixed magnetic body 10 to the second fixed magnetic body 20 and return to the S pole of the magnetic field generator 30, so that the magnetic sensor 40 has the first fixed magnetism. A magnetic flux passing between the body 10 and the second fixed magnetic body 20 is detected. Then, according to the movement of the magnetic field generator 30 in the movement direction X, the distance in the magnetic pole direction Y between the magnetic field generator 30 and the second fixed magnetic body 20 changes to pass through the magnetic sensor 40. Since the magnetic flux (density) changes, the position of the magnetic field generator 30, and thus the position of the shaft, etc. can be detected. The position detection principle of the position detection device is the same as the previous example.

In the position detection device, the shapes of the curved portion 11 and the

straight portions

12 and 13 of the first fixed magnetic body 10 are determined so that the magnetic flux density characteristics according to the movement of the magnetic field generator 30 are linear. . In the illustrated example, the magnetic flux density increases when the magnetic field generator 30 moves toward the straight portion 12, and the magnetic flux density decreases when it moves toward the straight portion 13. Therefore, in order to increase the position detection accuracy, it is important to increase the positioning accuracy of the first fixed magnetic body 10 and the second fixed magnetic body 20 with the magnetic field generator 30 interposed therebetween.
Therefore, in the first embodiment, there are

linear portions

12, 13, and 21 on the magnetic pole facing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20, and the

linear portions

12, 21 face each other. Moreover, the

linear portions

13 and 21 are also opposed to each other. In addition, since the

linear portions

12 and 21 and the opposing portions of the

linear portions

13 and 21 are at two places in the movement range of the magnetic field generator 30, the first fixed magnetic body 10 and the second fixed magnetic body 20 Positioning between them is possible. An example of the positioning method is shown in FIG. The jig 50 shown in FIG. 2 is formed with a narrow portion and a wide portion. The

straight portions

12 and 21 are positioned at the narrow portion, and the

straight portions

13 and 21 are positioned at the wide portion. . Then, a resin mold or the like may be used while maintaining the positional relationship between the first fixed magnetic body 10 and the second fixed magnetic body 20. Thereby, positioning between the 1st fixed magnetic body 10 and the 2nd fixed magnetic body 20 can be performed easily. Further, since the

straight portions

12 and 13 are located at both ends of the first fixed magnetic body 10, the maximum gap (that is, between the straight portions 13 and 21) and the minimum (that is, the straight portion) with respect to the second fixed magnetic body 20. Positioning between 12 and 21). Therefore, assembly accuracy can be improved.

Further, by arranging the magnetic field generator 30 and the magnetic sensor 40 in a straight line in the gap between the first fixed magnetic body 10 and the second fixed magnetic body 20, each of the components that affects the position detection performance in terms of assembly. As the positional relationship between the components requires only one gap and the management accuracy is one, assemblability is improved and the position detection accuracy is also improved.

FIG. 3 is a diagram showing another example of FIG. The first and second fixed

magnetic bodies

10 and 2 that are in the width in the magnetic pole direction Y of the magnetic sensor 40 are adjusted by adding the adjusting linear portion 14 separately from the

linear portions

12 and 13 and adjusting the position thereof. Adjustment of the gap of the body 20 is facilitated.

FIG. 4 is a diagram illustrating an example of assembly with another apparatus after the position detection apparatus is assembled. In FIG. 4, the magnetic field generator 30 and the magnetic sensor 40 are not shown. For example, when the position detection device is assembled to an actuator, insertion holes 61 and 62 are formed in the stator 60 of the actuator. The shaft hole 63 is a hole through which the shaft of the actuator passes, and the magnetic field generator 30 is attached to one end of the shaft passing through the shaft hole 63.
After assembly of the position detection device, the

straight portions

13 and 21 whose opposing surfaces are linear with each other at one end of the first fixed magnetic body 10 and the second fixed magnetic body 20 are inserted into the insertion holes 61 and 61 of the stator 60. 62 is fitted. Thereby, manufacturability and assembly position accuracy can be improved.
In the example of FIG. 4, the example in which the opposing

straight portions

13 and 21 are assembled to the stator 60 has been described, but conversely, the

linear portions

12 and 21 may be assembled to the stator 60.

FIG. 5 is a diagram showing another example of the assembly with another device after the assembly of the position detection device. The straight portion 13 a of the first fixed magnetic body 10 has a shape in which the width is increased in a direction perpendicular to the plane formed by the moving direction X and the magnetic pole direction Y of the magnetic field generator 30. By adopting such a shape, it is possible to widen the positioning range, leading to an improvement in position accuracy. In addition, the length of the linear portion 13a in the moving direction X can be shortened, leading to downsizing of the position detection device.

As shown in FIG. 1, the first fixed magnetic body 10 and the second fixed magnetic body 10 are formed so that the

linear portions

12 and 13 of the first fixed magnetic body 10 overlap the moving range of the magnetic field generator 30. The length of the fixed magnetic body 20 in the movement direction X can be reduced, and the position detection device can be downsized.

The magnetic field generator 30 is a permanent magnet, for example, a samarium / cobalt square magnet.
The magnetic sensor 40 includes a temperature detection element inside and uses a Hall element with an ASIC (Application Specific Integrated Circuit) that can program a temperature compensation function. The Hall IC having these functions is used for the magnetic sensor 40, and the zero point and the output gradient are adjusted so that the output does not fluctuate even in a high temperature environment.

As described above, according to the first embodiment, the position detection device has the N-polar polarity surface and the S-polarity surface on the back side thereof, and is attached to the reciprocating drive shaft so that the NS poles are aligned. A magnetic field generator 30 that moves in a moving direction X orthogonal to Y, a first fixed magnetic body 10 that is disposed opposite to one polarity surface of the magnetic field generator 30, and the other polarity of the magnetic field generator 30. The magnetic flux passing through the second fixed magnetic body 20 disposed opposite to the surface and sandwiched between the opposing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 is detected. The first fixed magnetic body 10 has a curved portion 11 and

straight portions

12 and 13 parallel to the moving direction X on a surface facing one of the polar surfaces, and has a second fixed magnetism. The body 20 has a straight portion 2 whose surface facing the other polar surface is parallel to the moving direction X. In the magnetic sensor 40, the magnetic flux passing therethrough changes as the distance in the magnetic pole direction Y between the magnetic field generator 30 and the first fixed magnetic body 10 changes according to the reciprocating motion of the drive shaft. From this, the position of the magnetic field generator 30 is detected. For this reason, it becomes possible to position the surfaces of the first pinned magnetic body 10 and the second pinned magnetic body 20 sandwiching the magnetic field generator 30 with the

straight portions

12 and 21 and the

straight portions

13 and 21. The positioning of the first fixed magnetic body 10 and the second fixed magnetic body 20 can be performed accurately and easily. Further, the linear portion 21 of the second fixed magnetic body 20 can be used as a guide for moving the magnetic field generator 30, and the magnetic field generator 30 is fixed to the first fixed magnetic body 10 and the second fixed magnetic body 20. It is possible to move the magnetic body 20 smoothly without changing with respect to the facing surface. Therefore, it is not necessary to separately provide a guide mechanism and a vibration proof mechanism, and the position detection device can be downsized.

Further, according to the first embodiment, the

straight portions

12 and 13 of the first fixed magnetic body 10 are formed at both ends of the movement range of the surface facing the one polar surface of the magnetic field generator 30, and the curved portion 11. Is formed between the

straight portions

12 and 13. For this reason, the linear portions 13 and 21 (or the linear portions 12 and 21) facing each other are provided at the end portions of the first fixed magnetic body 10 and the second fixed magnetic body 20 to have a movable portion whose position is to be detected. Assembly to the device can be easily performed. Further, since the

straight portions

12 and 13 are located at both ends of the movement range, the first fixed magnetic body 10 and the second fixed magnetic body 20 can be positioned at the maximum position and the minimum position of the gap. Accuracy can be improved.

In addition, according to the first embodiment, the curved portion 11 and the

straight portions

12 and 13 of the first fixed magnetic body 10 are formed within the moving range of the surface facing the one polar surface of the magnetic field generator 30. Made the configuration. For this reason, the first fixed magnetic body 10 and the second fixed portion are compared with the case where the straight portions 12, 21 (or the straight portions 13, 21) used for positioning and assembling to other devices are formed outside the movement range. The length of the magnetic body 20 in the moving direction X can be shortened, and the position detecting device can be downsized.

Further, according to the first embodiment, the gap formed by the facing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 extends on the extension line X in the movement direction of the magnetic field generator 30. The magnetic sensor 40 is configured to be installed in a state sandwiched between opposing surfaces of the extended portion. For this reason, the gap extends in one direction, and the magnetic sensor 40 and the magnetic field generator 30 can be arranged in a straight line in the gap, so that the position management of the first fixed magnetic body 10 and the second fixed magnetic body 20 can be performed. It can be in one place. This facilitates assembly.

Embodiment 2. FIG.
FIG. 6 is a diagram showing a position detection device according to Embodiment 2 of the present invention. 6 that are the same as or equivalent to those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.
In the position detection apparatus according to the second embodiment, the second fixed magnetic body 20 has an L shape in which one end in the moving direction X of the magnetic field generator 30 is bent vertically, and the vertically bent protruding portion 22 is provided. It faces the first fixed magnetic body 10. As a result, the gap formed by the opposing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 is also bent vertically from the extension line in the moving direction X to the first fixed magnetic body 10 side. It is extended. Then, by arranging the magnetic sensor 40 between the opposing surfaces of the protruding portion 22 and the first fixed magnetic body 10, the magnetic field generator 30 and the magnetic sensor 40 are arranged vertically. That is, the magnetic pole direction Y of the magnetic field generator 30 and the magnetic flux detection direction of the magnetic sensor 40 are perpendicular.
In the case of this configuration, the length of the installation portion of the magnetic sensor 40 can be shortened as compared with the configuration of the first embodiment shown in FIG. It becomes a structure.
However, since there are two gaps, a portion extending in the movement direction X and a portion extending in the magnetic pole direction Y, the position management of the first fixed magnetic body 10 and the second fixed magnetic body 20 is also two places. .

In the example of FIG. 6, the protrusion 22 is formed on the second fixed magnetic body 20 in order to make the gap bent in a direction perpendicular to the movement direction X, but the present invention is not limited to this. is not.
FIG. 7 is a modification of the position detection device. In this example, one end in the movement direction X of the first fixed magnetic body 10 is formed into an L shape which is bent vertically to the second fixed magnetic body 20 side, and the vertically bent protrusion 15 is the second fixed magnetic body. Opposes the body 20. Thereby, the gap formed by the opposing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 is bent vertically from the extension line in the moving direction X to the second fixed magnetic body 20 side. It is extended. And the magnetic sensor 40 is arrange | positioned in the extended part.
In the case of this configuration as well, the position detection device is downsized by reducing the overall length in the movement direction X.

FIG. 8 shows another modification of the position detection device. In this example, one end of the first fixed magnetic body 10 and one end of the second fixed magnetic body 20 are both formed into an L shape bent in a direction perpendicular to the moving direction X of the magnetic field generator 30, and the projecting portions 15. , 22 face each other. Thereby, the gap formed by the opposing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 is bent vertically from the extension line in the moving direction X to the second fixed magnetic body 20 side. It is extended. And the magnetic sensor 40 is arrange | positioned in the extended part.
In the case of this configuration as well, the position detection device is downsized by reducing the overall length in the movement direction X.

In the examples of FIGS. 6 to 8, a magnetic sensor is formed by extending a gap formed by facing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 in a direction perpendicular to the moving direction X. However, the present invention is not limited to the vertical extension, and the magnetic sensor 40 may be arranged at an arbitrary angle with respect to the movement direction X.
FIG. 9 is a modification of the position detection device. In this example, the projecting

portions

15 and 22 are formed so as to project obliquely with respect to the movement direction X. As a result, the gap formed by the opposing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 is extended in a shape that is bent obliquely downward from the extension line in the movement direction X. And the magnetic sensor 40 is arrange | positioned in the extended part.
In the case of this configuration as well, the position detection device is downsized by reducing the overall length in the movement direction X.

FIG. 10 shows another modification of the position detection device. In this example, one end of the second fixed magnetic body 20 is bent vertically to the first fixed magnetic body 10 side, and the tip thereof is bent to the first fixed magnetic body 10 side to form a bowl-shaped bowl-shaped protrusion. 23. On the other hand, the first fixed magnetic body 10 cuts the upper end portion opposed to the hook-shaped protrusion 23 within the range in which the flowing magnetic flux is not saturated, thereby forming the inclined portion 16. Thereby, the gap formed by the opposing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 is folded back from the extension line in the moving direction X and extended in an oblique direction. And the magnetic sensor 40 is arrange | positioned in the extended part extended diagonally with respect to the moving direction X. As shown in FIG.
In the case of this configuration, since the length in the moving direction X and the length in the magnetic pole direction Y for installing the magnetic sensor 40 can be shortened, the position detecting device can be further downsized.

As described above, according to the second embodiment, the gap formed by the opposed surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 of the position detection device is on the extension line X in the moving direction of the magnetic field generator 30. The magnetic sensor 40 is installed in a state of being sandwiched between opposing surfaces of the extended portion. For this reason, the position detection device can be shortened (downsized) with respect to the moving direction X of the magnetic field generator 30.
In particular, when the gap is extended in the direction perpendicular to the moving direction X extension line of the magnetic field generator 30, the effect of downsizing the position detecting device in the moving direction X is great.

Further, according to the second embodiment, the first fixed magnetic body 10 is arranged on the surface opposite to the surface facing the one polar surface of the magnetic field generator 30 in the moving direction X of the magnetic field generator 30. The second fixed magnetic body 20 has an inclined portion 16 that is inclined with respect to the first fixed magnetic body 10 and protrudes from the end of the surface facing the other polar surface of the magnetic field generator 30 to the first fixed magnetic body 10 side. And the gap extends along the opposing surface of the first fixed magnetic body 10 and the hook-like protrusion 23, and the magnetic sensor 40 is provided with the extension of the hook-like protrusion 23. It was set as the structure installed in the state pinched | interposed into the opposing surface of the inclination part 16 and the hook-shaped protrusion part 23 which comprise a part. For this reason, since the magnetic sensor 40 can be installed in the space cut in order to form the inclination part 16 in the 1st fixed magnetic body 10, a position detection apparatus can be further reduced in size.

Embodiment 3 FIG.
FIG. 11 is a diagram showing a position detection apparatus according to Embodiment 3 of the present invention. 11 that are the same as or equivalent to those in FIG. 6 are given the same reference numerals, and descriptions thereof are omitted.
The third embodiment is a modification of the second embodiment, in which the length of the protruding portion 22 protruding in the direction perpendicular to the moving direction X of the magnetic field generator 30 is set to be perpendicular to the first fixed magnetic body 10. A step Δh is provided shorter than the length in the direction. By providing the step Δh, the resolution of the magnetic flux detected by the magnetic sensor 40 can be increased.

FIG. 12A is a graph showing the relationship of the input signal (magnetic flux density) to the magnetic sensor 40 according to the position of the magnetic field generator 30, where the horizontal axis is the position of the magnetic field generator 30 and the vertical axis is the input of the magnetic sensor 40. Signal. However, when the magnetic sensor 40 has a characteristic (linearity) for linearly outputting an output signal with respect to an input signal (magnetic flux density), the same result is obtained even if the vertical axis of the graph is the output signal. Hereinafter, the input signal and the output signal are not distinguished and are simply referred to as a detection signal.
12B (a) shows a case where no step Δh is provided, and FIG. 12B (b) shows a case where a step Δh in which the length of the protrusion 22 is shorter than the length of the first fixed magnetic body 10 is provided (same as FIG. 11). FIG. 12B (c) shows a case where a step Δh in which the length of the protruding portion 22 is longer than the length of the first fixed magnetic body 10 is provided. Moreover, the detection signals at the positions A and B of the magnetic field generator 30 shown in FIG. 12B correspond to A and B in the graph of FIG. 12A.

As shown in FIGS. 12B (b) and 12 (c), by providing the step Δh, the magnetic flux density of the first fixed magnetic body 10 and the second fixed magnetic body 20 sandwiching the magnetic field generator 30 is increased. That is, the magnetic flux detected by the magnetic sensor 40 can be increased. Therefore, in the configuration of FIG. 12B (a) without the step Δh, the detection signal width I of the magnetic sensor 40 in the graph of FIG. 12A is different from the detection signal width of the configuration of FIG. 12B (b) with the step Δh. II, and the signal width increases. By increasing the signal width of the detection signal with respect to the position of the magnetic field generator 30, the resolution of the position of the magnetic field generator 30 can be increased. In FIG. 12B (b), the length of the protrusion 22 is shorter than the length of the first fixed magnetic body 10, but the length of the first fixed magnetic body 10 protrudes as shown in FIG. 12B (c). Even if it is shorter than the length of the portion 22, it is the same.
Further, in FIG. 12B (b), there is a space at the upper end portion of the protrusion 22 by the amount provided with the step Δh, and in FIG. 12B (c), the first fixed magnetic body 10 is provided by the amount provided with the step Δh. Since there is a space in the upper side portion, it is possible to route wiring or install an electronic substrate in this space, and the position detection device can be miniaturized.

In order to increase the density of magnetic flux passing through the magnetic sensor 40, for example, the configuration shown in FIG. FIG. 13 is a modified example of the position detection device according to the third embodiment, in which the portions where the magnetic sensor 40 abuts on each of the opposing surfaces of the protruding portion 22 and the first fixed magnetic body 10 are protruded and protruded. Installation surfaces 17 and 24 are formed. In the convex installation surfaces 17 and 24, the cross-sectional area is reduced to increase the magnetic resistance, and the distance between the convex installation surfaces 17 and 24 is shorter than the distance between the protrusion 22 and the first fixed magnetic body 10. Therefore, the magnetic flux flowing through the magnetic sensor 40 can be collected. Thereby, the detection range in the magnetic sensor 40 can be enlarged, and the resolution of the magnetic sensor 40 can be increased. Thereby, the shape of the magnetic field generator 30 can be reduced.
In the example of FIG. 13, the convex installation surfaces 17 and 24 are formed on both the first fixed magnetic body 10 and the second fixed magnetic body 20, but the same effect can be obtained even if only one of them is formed. . For example, the adjustment linear portion 14 shown in FIG. 3 described above has the same effect as the convex installation surface.

As described above, according to the third embodiment, the opposing surfaces constituting the gap between the first fixed magnetic body 10 and the second fixed magnetic body 20 have different lengths. For this reason, by changing the length, it is possible to reduce the size of one or both of the first fixed magnetic body 10 and the second fixed magnetic body 20 and reduce the size of the position detection device. It becomes. Moreover, since the detection range of the magnetic sensor 40 can be increased, the resolution can be increased.

In addition, according to the third embodiment, the position detection device has a protruding configuration that protrudes from the opposing surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20 and contacts the magnetic sensor 40. The

surfaces

17 and 24 were provided. For this reason, the magnetic flux which passes the magnetic sensor 40 can be concentrated, and the detection range of the magnetic sensor 40 can be enlarged to increase the resolution.

In the above description, the case where the configuration of the third embodiment is applied to the second embodiment has been described. However, the present invention is not limited to this, and can be applied to the first embodiment.

Embodiment 4 FIG.
FIG. 14 is a diagram showing a position detection apparatus according to Embodiment 4 of the present invention. In FIG. 14, the same or corresponding parts as in FIG.
The fourth embodiment is a modification of the third embodiment, in which the orientation of the lead wire 41 of the magnetic sensor 40 installed between the first fixed magnetic body 10 and the second fixed magnetic body 20 is changed to a magnetic field. The generator 30 is arranged in a direction perpendicular to the moving direction X of the generator 30. More specifically, the lead wire 41 is extended in a direction perpendicular to the plane composed of the moving direction X and the magnetic pole direction Y (that is, the direction perpendicular to the paper surface). With this configuration, the lead wire 41 can be connected to an external terminal or an electronic substrate (not shown) on the side surfaces of the first fixed magnetic body 10 and the second fixed magnetic body 20, and the total length of the position detection device in the movement direction X can be increased. The structure can be reduced and reduced in size.

Alternatively, as shown in FIG. 6 of the second embodiment, the direction of the lead wire 41 may be arranged in a direction perpendicular to the moving direction X (that is, upward direction on the paper). Also in this configuration, the total length of the movement detection device in the movement direction X can be reduced and the size can be reduced.

As described above, according to the fourth embodiment, the magnetic sensor 40 is installed such that the direction of the lead wire 41 is perpendicular to the moving direction X of the magnetic field generator 30. For this reason, the arrangement location of the electronic substrate connected to the magnetic sensor 40 can be changed, and the position detection device can be downsized.

In the above description, the configuration of the fourth embodiment is applied to the third embodiment. However, the present invention is not limited to this, and can be applied to the first and second embodiments. is there.

Embodiment 5. FIG.
15A and 15B are views showing a position detection device according to Embodiment 5 of the present invention, in which FIG. 15A is a plan view and FIG. 15B is a front view. 15 that are the same as or equivalent to those in FIG. 11 are denoted by the same reference numerals and description thereof is omitted.
The fifth embodiment is a modification of the third embodiment, and the width w1 in the direction orthogonal to the moving direction X of the magnetic field generator 30 as viewed from the magnetic pole direction Y as shown in FIG. The first fixed magnetic body 10 and the second fixed magnetic body 20 are configured to be larger than the width w2 in the orthogonal direction. When the width w1 is configured to be equal to or less than the width w2, when the lateral displacement occurs in the direction orthogonal to the moving direction X when the magnetic field generator 30 is moved, the magnetic field generator 30 is moved to the first fixed magnetic body 10 and the second fixed magnetic body 10. Since the change occurs in the area overlapping with the fixed magnetic body 20, the sensor accuracy (linearity) is affected. On the other hand, since the width w1 is configured to be larger than the width w2 in the fifth embodiment, the magnetic flux density passing through the magnetic sensor 40 does not change even if a lateral displacement occurs, and the sensor accuracy is not affected.
Further, in this configuration, since the surface area of the magnetic field generator 30 is increased and the cooling surface is increased, the magnetic field generator 30 has an effect of cooling the magnet. Therefore, this position detection device can be used in a high temperature atmosphere.

As described above, according to the fifth embodiment, the width w1 of the magnetic field generator 30 is larger than the width w2 of the first fixed magnetic body 10 and the second fixed magnetic body 20 on the plane in which the magnetic field generator 30 moves. It comprised so that it might become. For this reason, even if a lateral displacement occurs in the magnetic field generator 30, the amount of magnetic flux passing through the first fixed magnetic body 10 and the second fixed magnetic body 20 does not change, and the detection accuracy of the magnetic sensor 40 is affected. I can not. In addition, since the surface area of the magnetic field generator 30 is increased, the cooling surface is increased, which is effective for cooling the magnet.

In the above description, the case where the configuration of the fifth embodiment is applied to the third embodiment has been described. However, the present invention is not limited to this and may be applied to the first, second, and fourth embodiments. Is possible.

Embodiment 6 FIG.
FIG. 16 is a view showing a position detection apparatus according to Embodiment 6 of the present invention, and FIG. 17 shows an external perspective view in which the first fixed magnetic body 10 and the second fixed magnetic body 20 are integrated. 16 and 17, the same or corresponding parts as those in FIG. 6 are denoted by the same reference numerals and description thereof is omitted.
The sixth embodiment is a modification of the second embodiment. As described above, the positional relationship accuracy between the first fixed magnetic body 10 and the second fixed magnetic body 20 is an important factor in sensor accuracy (linearity). However, as a configuration for further improving the accuracy, As shown in FIGS. 16 and 17, the positional relationship accuracy can be improved by integrating a part of the first fixed magnetic body 10 and the second fixed magnetic body 20 at the connecting portion 25. . By doing so, the positional accuracy of each component is improved, which leads to an improvement in sensor accuracy.

Note that if the width of the connecting portion 25 in the magnetic pole direction Y is narrowed so as to be magnetically saturated with respect to the magnetic flux of the magnetic field generator 30, the detected magnetic flux of the magnetic sensor 40 is not affected. Accuracy can be maintained.
In addition, in this configuration, since the first fixed magnetic body 10 and the second fixed magnetic body 20 are a single component, the assemblability is improved and the manufacturing can be performed at a low cost. Further, after the first fixed magnetic body 10, the second fixed magnetic body 20 and the connecting portion 25 are integrally formed into one component shown in FIG. 17 (further, the first fixed magnetic body 10 and the second fixed magnetic body 20 may be separated from each other), the connecting portion 25 may be cut to make the first fixed magnetic body 10 and the second fixed magnetic body 20 separate parts. By doing so, the magnetic flux density passing through the magnetic sensor 40 can be stabilized at the same level as the configuration described in the second embodiment.

In FIGS. 16 and 17, the connecting portion 25 is provided so as to partially connect the opposing surfaces of the protruding portion 22 formed for installing the magnetic sensor 40 and the first fixed magnetic body 10. The position where the connecting portion 25 is provided is not limited to this.
FIG. 18 is another example of the connecting portion 25. In this example, as shown in FIG. 18A, two connecting

portions

25a and 25b are provided on the opposing surfaces of the protruding portion 22 where the magnetic sensor 40 is installed and the first fixed magnetic body 10, thereby A hole into which the magnetic sensor 40 is inserted can be formed in the fixed magnetic body including the first fixed magnetic body 10 and the second fixed magnetic body 20. By doing so, as shown in FIG. 18B, the magnetic sensor 40 can be inserted from the direction perpendicular to the paper surface, and the positioning accuracy for fixing the magnetic sensor 40 is improved.
In addition, the connection part 25 may be provided in places other than the example of illustration, and the 1st fixed magnetic body 10 and the 2nd fixed magnetic body 20 may be connected.

FIG. 18C shows an example in which the first fixed magnetic body 10 and the second fixed magnetic body 20 are formed of laminated steel plates. Although the 1st fixed magnetic body 10 and the 2nd fixed magnetic body 20 should just be a magnetic body, it is more preferable that it is comprised with the laminated steel plate. By using laminated steel sheets, eddy currents generated in the first fixed magnetic body 10 and the second fixed magnetic body 20 are suppressed, and the magnetic flux in the magnetic field generator 30 is easily detected by the magnetic sensor 40. is there.
Moreover, you may form with the powder iron core. As with the laminated steel plate, eddy current can be suppressed.

As described above, according to the sixth embodiment, the first fixed magnetic body 10 and the second fixed magnetic body 20 are partially connected. For this reason, by positioning the first fixed magnetic body 10 and the second fixed magnetic body 20 in a state where they are connected by the connecting portion 25, positioning accuracy can be ensured at the time of forming. And by ensuring positioning accuracy, it becomes possible to improve the output linearity (linearity) of the magnetic sensor 40. Moreover, since the 1st fixed magnetic body 10 and the 2nd fixed magnetic body 20 can be shape | molded at once, and a number of parts can be reduced, productivity can be improved.
In particular, the first fixed magnetic body 10 and the second fixed magnetic body 20 are configured by partially connecting the opposing surfaces on which the magnetic sensor 40 is installed, thereby affecting the detected magnetic flux of the magnetic sensor 40. Therefore, the sensor accuracy can be maintained.

In the above description, the configuration of the sixth embodiment is applied to the second embodiment. However, the present invention is not limited to this, and may be applied to the first, third, and fifth embodiments. Is possible.

Embodiment 7 FIG.
FIG. 19 is a plan view showing a position detection apparatus according to Embodiment 7 of the present invention. In FIG. 19, parts that are the same as or equivalent to those in FIG.
The seventh embodiment is a modification of the second embodiment, and is provided with a positioning mechanism that regulates the movable range in the movement direction X of the magnetic field generator 30. In the example of FIG. 19, the magnetic field generator 30 is configured with a magnetic field generator holder 70, and the magnetic field generator holder 70 is provided with a moving side stopper 71 having a shape protruding outward. There is a housing 72 that holds the outer surface sides of the first fixed magnetic body 10 and the second fixed magnetic body 20, and the housing 72 also includes fixed-

side stoppers

73 a and 73 b. When the magnetic field generator 30 moves in the movement direction X, the movement-side stopper 71 and the fixed-side stopper 73a come into contact with each other, thereby restricting the movement of the magnetic field generator 30. At this position, the detection signal of the magnetic sensor 40 is maximized. On the other hand, at the position where the moving side stopper 71 and the fixed side stopper 73b abut, the detection signal of the magnetic sensor 40 is minimized. Therefore, the detection signal range of the magnetic sensor 40 in the movable range of the magnetic field generator 30 can be easily confirmed.

Thereby, for example, a Hall IC corresponding to the maximum magnetic flux density when the magnetic field generator 30 is in contact with the fixed side stopper 73a is prepared as the magnetic sensor 40, or information on the detection signal range is stored in the IC program. Can be written on. Therefore, it is possible to determine the detection signal range alone without assembling the position detection device to an actuator to be detected and measuring the detection signal range.

In the example of FIG. 19, the fixed

side stoppers

73a and 73b are provided to restrict the movement of the magnetic field generator 30 to both sides in the moving direction X. However, the fixed side stopper 73a or the fixed side stopper is used. Only one of the portions 73b may be provided to restrict the movement in one direction of the movement direction X.
Moreover, it is good also as a structure which makes the magnetic field generator 30 contact | abut directly to the fixed

side stopper part

73a, 73b instead of forming a stopper in the magnetic field generator holding | maintenance part 70 holding the magnetic field generator 30. FIG.

As described above, according to the seventh embodiment, the position detection device includes the fixed-

side stoppers

73a and 73b that are provided at both ends of the moving range of the magnetic field generator 30 and contact the magnetic field generator 30. Therefore, the movable range of the magnetic field generator 30 can be regulated.

In the above description, the case where the configuration of the seventh embodiment is applied to the second embodiment has been described. However, the present invention is not limited to this and may be applied to the first, third to sixth embodiments. Is possible.

Embodiment 8 FIG.
FIG. 20 is a longitudinal section of an actuator (drive source) equipped with a position detection device according to Embodiment 8 of the present invention. As the actuator, a motor will be described in the eighth embodiment. Note that the position detection device of the present invention can be used as long as it is an actuator that is linearly driven. 20 that are the same as or correspond to those in FIG. 11 are denoted by the same reference numerals and description thereof is omitted.

In FIG. 20, when a voltage is applied to a terminal 102 in an external input / output connector 101 provided in the actuator 100, a current flows through a coil 104 wound around a stator (yoke) 103, and polarization is applied to a plurality of poles. The fixed stator 103 is NS magnetized according to the direction of current. Thereby, the rotor 106 provided with the magnet 105 magnetized with NS rotates. The rotor 106 is held by a bearing (bearing) 107.
Inside the rotor 106, a screw mechanism 108 on the female screw side for converting the rotation into a linear motion is configured, and a screw mechanism 110 on the male screw side formed on the outer peripheral surface of the shaft (output shaft) 109; Engagement and rotation of the rotor 106 transmits force to the shaft 109. By providing a rotation prevention mechanism at the sliding portion of the boss 111 inserted through the shaft 109, the shaft 109 moves linearly.

On the other hand, on the side of the position detection device, as shown in FIG. 20, the first fixed magnetic body 10, the second fixed magnetic body 20, and the magnetic sensor 40 are arranged, and the magnetic field generator 30 is made of a nonmagnetic material. The sensor shaft (drive shaft) 112 is connected. For example, the sensor shaft 112 insert-molds the magnetic field generator 30 with a resin mold. The sensor shaft 112 and the shaft 109 of the actuator 100 are connected at the end face, and the sensor shaft 112 and the magnetic field generator 30 move in conjunction with the linear movement of the shaft 109, and the position is detected by the magnetic sensor 40. It has a structure to detect. The lead wire 41 of the magnetic sensor 40 is routed to the electronic substrate 113 side and is electrically connected to the terminal 102.
The shaft 109 and the sensor shaft 112 do not have to be connected and integrated. For example, in a state where the sensor shaft 112 is in contact with the end surface of the shaft 109, the shaft 109 and the sensor shaft 112 are biased by a spring or the like from the position detection device side toward the shaft 109. It may be configured as described above.

In such an actuator 100, the magnetic sensor 40 may malfunction due to the influence of noise generated from a motor including the stator 103 and the rotor 106. Therefore, the magnetic sensor 40 is arranged on the side (opposite side) far from the motor body, thereby reducing the influence of the noise and improving the noise resistance performance.

Conversely, the magnetic sensor 40 may be disposed on the side close to the motor body.
FIG. 21 is a longitudinal sectional view showing another example of the actuator, and shows a configuration diagram in which the magnetic sensor 40 is mounted on the side of the actuator 100 close to the motor. With this structure, the electrical connection between the lead wire 41 of the magnetic sensor 40 and the terminal 102 can be facilitated, and productivity can be improved. In addition, since the space for routing the wiring connecting the lead wire 41 and the terminal 102 can be reduced, the actuator 100 can be downsized. Further, since the magnetic sensor 40 is disposed inside the actuator 100, the influence of external noise, static electricity, etc. can be reduced.

In the case of FIG. 21, the sensor shaft 112 needs to be configured to pass through the second fixed magnetic body 20. As an example, FIG. 22 shows a cross-sectional view of the second fixed magnetic body 20 taken along the line AA of FIG. The second fixed magnetic body 20 is formed with a hole 26 through which the sensor shaft 112 penetrates, and an enlarged diameter portion 27 having an enlarged cross-sectional area corresponding to the opening area of the hole 26 is formed to ensure a passage area of magnetic flux. is doing.
As another example, FIG. 23 shows a view of the second fixed magnetic body 20 and the sensor shaft 112 as seen from the direction of arrow B in FIG. In this example, the sensor shaft 112 is configured to be bifurcated in the middle to bypass the protrusion 22.

The direction of the lead wire 41 may be determined in accordance with the structure of the actuator 100, and it goes without saying that the lead wire 41 may be arranged in a direction other than the direction shown in FIGS.

As described above, according to the eighth embodiment, the position detection device is configured to dispose the magnetic sensor 40 on the near side and the magnetic field generator 30 on the far side with respect to the actuator 100 that drives the sensor shaft 112. For this reason, the magnetic sensor 40 becomes less susceptible to noise and leakage magnetic fields from the motor and actuator 100, and the position detection error of the position detection device can be reduced.

Further, according to the eighth embodiment, contrary to the above configuration, the magnetic sensor 40 is disposed on the far side and the magnetic field generator 30 is disposed on the near side with respect to the actuator 100 that drives the sensor shaft 112. Good. In this case, the lead wire 41 of the magnetic sensor 40 can be easily electrically connected to the motor and actuator 100 side, and productivity can be improved. Further, since the magnetic sensor 40 approaches the motor and actuator 100 side, a space required for wiring and the like can be reduced, and the entire actuator 100 can be reduced in size.

In the above description, the case where the position detection device according to the third embodiment is mounted on the actuator 100 has been described. It is also possible to mount a device.

Further, as described in the sixth embodiment, the first fixed magnetic body 10 and the second fixed magnetic body 20 of the first to eighth embodiments may be magnetic bodies, but are composed of laminated steel plates. It is more preferable. Moreover, you may form with the powder iron core.

Further, within the scope of the present invention, the invention of the present application can be freely combined with each embodiment, modified with any component in each embodiment, or omitted with any component in each embodiment. .

As described above, since the position detection device according to the present invention has a vibration resistance while being reduced in size, a throttle valve, an EGR (Exhaust Gas Recirculation) valve, a WG (Waste Gate) valve mounted on the vehicle, It is suitable for use in a position detection device that detects the shaft position of an actuator that drives a movable vane or the like of a VG (Variable Geometric) turbo system.

10 first fixed magnetic body, 11 curved portion, 12, 13, 13a linear portion, 14 adjusting linear portion, 15 protruding portion, 16 inclined portion, 17 convex installation surface, 20 second fixed magnetic body, 21 linear Part, 22 projecting part, 23 bowl-shaped projecting part, 24 convex installation surface, 25, 25a, 25b connecting part, 26 holes, 27 diameter expanding part, 30 magnetic field generator, 40 magnetic sensor, 41 lead wire (electrode terminal) , 50 jig, 60 stator, 61, 62 insertion hole, 63 shaft hole, 70 magnetic field generator holding part, 71 moving side stopper part, 72 housing. 73a, 73b fixed side stopper, 91 first fixed magnetic body, 92 second fixed magnetic body, 93 magnetic field generator, 94 magnetic sensor, 100 actuator, 101 external input / output connector, 102 terminal, 103 stator, 104 coils, 105 magnets, 106 rotors, 107 bearings, 108, 110 screw mechanisms, 109 shafts, 111 bosses, 112 sensor shafts (drive shafts), 113 electronic boards.

Claims

A magnetic field generator having an N-polar polarity surface and an S-polarity surface on the back side thereof, attached to a reciprocating drive shaft and moving in a direction perpendicular to the magnetic pole direction in which the NS poles are arranged;
A first fixed magnetic body disposed opposite to one polar surface of the magnetic field generator;
A second fixed magnetic body disposed opposite to the other polar surface of the magnetic field generator;
A magnetic sensor that is installed in a state sandwiched between opposing surfaces of the first fixed magnetic body and the second fixed magnetic body, and that detects a magnetic flux passing therethrough,
The first fixed magnetic body has a curved portion on a surface facing the one polar surface and two straight portions parallel to the moving direction of the magnetic field generator,
The second fixed magnetic body is a linear portion whose surface facing the other polar surface is parallel to the moving direction,
In the magnetic sensor, the magnetic flux passing therethrough changes as the distance in the magnetic pole direction between the magnetic field generator and the first fixed magnetic body changes according to the reciprocating motion of the drive shaft. A position detection device for detecting a position of the magnetic field generator.
The two linear portions of the first fixed magnetic body are formed at both ends of the movement range of the surface facing the one polar surface of the magnetic field generator, and the curved portion is formed between the two linear portions. The position detection device according to claim 1, wherein
3. The position detection according to claim 2, wherein the curved portion and the two straight portions of the first fixed magnetic body are formed within a moving range of a surface facing one polar surface of the magnetic field generator. apparatus.
The opposing surfaces of the first fixed magnetic body and the second fixed magnetic body are extended on an extension line in the moving direction of the magnetic field generator, and the magnetic sensor is installed in a state sandwiched between the opposing surfaces of the extended portion. The position detection device according to any one of claims 1 to 3, wherein
The opposing surfaces of the first fixed magnetic body and the second fixed magnetic body extend in a direction shifted from the extension line of the moving direction of the magnetic field generator, and the magnetic sensor is sandwiched between the opposing surfaces of the extended portion. The position detection device according to claim 1, wherein the position detection device is installed in a closed state.
6. The position detecting device according to claim 5, wherein the opposing surfaces of the first fixed magnetic body and the second fixed magnetic body are extended in a direction perpendicular to the moving direction extension line of the magnetic field generator. .
The first fixed magnetic body has an inclined portion inclined with respect to the moving direction of the magnetic field generator on the surface opposite to the surface facing the one polar surface of the magnetic field generator,
The second fixed magnetic body has a hook-shaped protrusion that protrudes from the end of the surface facing the other polar surface of the magnetic field generator toward the first fixed magnetic body and is bent toward the inclined portion. Have
6. The position detecting device according to claim 5, wherein the magnetic sensor is installed in a state sandwiched between opposing surfaces of the inclined portion and the hook-shaped protruding portion.
The position detection device according to any one of claims 1 to 7, wherein the opposing surfaces of the first fixed magnetic body and the second fixed magnetic body have different lengths.
2. A convex installation surface that protrudes from one or both of the opposing surfaces of the first fixed magnetic body and the second fixed magnetic body and that abuts against the magnetic sensor. The position detection device according to claim 8.
10. The position detecting device according to claim 1, wherein the magnetic sensor is installed such that the direction of the electrode terminal is perpendicular to the moving direction of the magnetic field generator.
The width of the magnetic field generator is larger than the widths of the first fixed magnetic body and the second fixed magnetic body on the plane in which the magnetic field generator moves. The position detection device according to claim 1.
The position detecting device according to any one of claims 1 to 11, wherein the first fixed magnetic body and the second fixed magnetic body are partially connected to each other.
13. The position detecting device according to claim 12, wherein the first fixed magnetic body and the second fixed magnetic body are configured by partially connecting opposing surfaces on which the magnetic sensor is installed.
The position according to any one of claims 1 to 13, further comprising a stopper portion that is provided at both ends or one end portion of the moving range of the magnetic field generator and contacts the magnetic field generator. Detection device.
The position detection according to any one of claims 1 to 14, wherein a magnetic sensor is disposed on a far side and a magnetic field generator is disposed on a near side with respect to a drive source for driving the drive shaft. apparatus.
The position detection according to any one of claims 1 to 14, wherein a magnetic sensor is disposed on a side closer to a drive source for driving a drive shaft, and a magnetic field generator is disposed on a side farther from the drive source. apparatus.