JPH10274547A - Position detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a position detecting device that can keep a clearance between a sensor and a magnetic recording medium constant, protect the surface of the sensor and reduce an error in correspondence with the attitude change of the sensor. SOLUTION: This device is used for straight line position detection. A magnetic recording medium 1 is a bar body for recording with the N-pole and S-pole arranged in the longitudinal direction. A sensor 2 senses the magnetic field magnetized to the magnetic recording medium 1 and converts it into an electric signal. A sensor holding part 3 fixes the sensor 2 and has a bearing part sliding along the magnetic recording medium 1. A detecting part of the sensor 2 is fixed into a position corresponding to the bearing part of the sensor holding part 3. The detecting part of the sensor 2 is included in a sliding direction length range of the bearing part. The sensor holding part 3 has one end face 18 formed of a plane vertical to a sliding direction, and this end face 18 pressure-contacts with a plane part 19 of a rotating support part 4 rotatable almost around the sensor detecting part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position detector, such as a position detector, a digital scale, a gauge, and an encoder, used for detecting the position of a straight line (relative position detection) in a machine tool, an industrial machine, or the like. .

[0002]

2. Description of the Related Art Conventional magnetoelectric transducers (hereinafter referred to as "sensors")
) As a magnetic sensor, the magnetic detection surface of the sensor is formed of a metal thin film and a thin protective material.

Therefore, in general, a sensor cannot be used in contact with a magnetic recording medium on which a position signal is magnetically recorded and a sensor. Therefore, the magnetic recording medium and the sensor are arranged so as to move relative to each other while maintaining a certain gap (hereinafter, referred to as “clearance”), thereby forming an encoder.

In a magnetic linear encoder composed of a rod-shaped magnetic recording medium and a sensor, the sensor is fixed to a member having a bearing by fitting or bonding, or fixed by a leaf spring, and the magnetic recording medium is passed through the bearing. Inserted. The gap between the magnetic recording medium and the sensor is kept constant by the bearing.

[0005]

In an actual use environment,
Since various foreign substances may enter the clearance, another protective cover may be attached to the sensor detection surface side by bonding or the like, as shown in FIG. 12, or rubber or felt may be attached to both ends in the movement direction of the sensor. There is a problem that the cost is increased due to the attachment of the dust guard.

Next, since the magnetic recording medium and the sensor are arranged so as to move relative to each other while maintaining a certain clearance, it is important to easily and accurately maintain the clearance.

[0007] Further, in the case of mounting on a machine tool or the like, if the portion to be mounted on the machine and the sensor holding unit are integrated, a shift at the time of mounting directly applies a load to the sensor holding unit, which causes an error. Therefore, as shown in FIG. 13, although some flexibility is provided for attachment using a leaf spring or the like, there still remains a problem that errors occur due to misalignment due to attachment or bending of the magnetic recording medium. .

The present invention has been made in view of such a problem, and maintains a constant clearance between a sensor and a magnetic recording medium, protects a sensor surface, and reduces an error corresponding to a change in the attitude of the sensor. It is an object of the present invention to provide a position detecting device that can perform the position detection.

[0009]

A position detecting device according to the present invention is characterized by a rod-shaped magnetic recording medium in which N and S poles are arranged and recorded in the longitudinal direction, and a magnetic field magnetized by the magnetic recording medium. While fixing the sensor that converts it to an electrical signal,
In a position detecting device having a sensor holding portion having a bearing portion that slides on a magnetic recording medium, the detecting portion of the sensor is fixed at a position corresponding to the bearing portion of the sensor holding portion, and the length of the bearing portion in the sliding direction. Range includes the detection unit of the sensor.

Further, the position detecting device of the present invention relates to a rod-shaped magnetic recording medium in which N poles and S poles are arranged and recorded in the longitudinal direction, and a magnetic field magnetized in the magnetic recording medium to generate an electric signal. In a position detecting device having a sensor for conversion and a sensor holding part having a bearing part sliding on a magnetic recording medium, the sensor holding part has one end face consisting of a plane perpendicular to the sliding direction. Then, this end face is pressed against a flat portion of the rotation support portion rotatable about the sensor detection portion as a center.

Further, the position detecting device of the present invention relates to a rod-shaped magnetic recording medium in which N poles and S poles are arranged and recorded in the longitudinal direction, and a magnetic field magnetized in the magnetic recording medium to generate an electric signal. In a position detecting device having a sensor to be converted and a sensor holding part having a bearing part sliding on a magnetic recording medium, the sensor holding part has two end faces consisting of a plane perpendicular to the sliding direction. And these end faces
The two rotation support portions rotatable about the sensor detection portion are respectively pressed and held by the flat portions.

Further, the position detecting device of the present invention is characterized in that a rod-shaped magnetic recording medium for recording by arranging N poles and S poles in the longitudinal direction and a magnetic field magnetized on the magnetic recording medium are converted into electric signals. In a position detection device having a sensor to be converted and a sensor holding part having a bearing part that slides on the magnetic recording medium, the sensor holding part has one end surface formed of a spherical surface having the sensor detection part as the center. This end face is pressed against the plate surface of the free supporting portion movable vertically to the sliding direction.

Further, the position detecting device of the present invention is characterized in that a rod-shaped magnetic recording medium for recording by arranging N poles and S poles in the longitudinal direction, and a magnetic field magnetized by the magnetic recording medium are converted into electric signals. In a position detection device having a sensor to be converted and a sensor holding part having a bearing part sliding on a magnetic recording medium, the sensor holding part has two end faces each formed of a spherical surface having the sensor detection part as a center. These end faces are pressed and sandwiched by respective plate faces of the free support portion and the pressing member which can move perpendicularly to the sliding direction.

Further, the position detecting device of the present invention is the position detecting device having the above-mentioned configuration, in which the magnetic recording medium performs magnetic recording over the entire circumference of a cross section perpendicular to the sliding direction.

[0015] In the sensor holding portion for mounting the sensor,
If a mounting surface is provided on the basis of the sensor detection surface, and a hole for passing the magnetic recording medium is provided at a position where the gap between the sensor and the magnetic recording medium becomes a predetermined value with respect to this surface, and the bearing is used as a bearing, By passing through a recording medium, a linear encoder can be configured. The sensor is joined to the sensor holding portion having a bearing portion by fitting, bonding, or the like.

In the present invention, if the hole through which the magnetic recording medium is passed is provided at least in the range of the detecting portion of the sensor, and if the outer periphery of the hole does not reach the mounting surface based on the sensor detecting surface, the sensor can be mounted. The sensor holding unit may be configured such that the unit, the bearing unit, and the sensor detection unit are integrally formed.

For example, when the reproducing wavelength is 200 μm and the diameter of the magnetic recording medium is Φ2000 μm, the set clearance is about 80 μm, and the allowable range is 20 μm.
About 120 μm.

Here, a radius of 1005 μm centered on a position of 1080 μm from the mounting surface with respect to the sensor detection surface.
If a holding part with a hole of m as a bearing is manufactured,
The clearance of m is maintained, and the protection member of this clearance amount is integrally formed.

The length of the bearing portion may be longer than the length of the sensor detecting portion. If the length of the bearing portion is longer than the length in the detecting direction of the sensor, the portion on the detecting side of the sensor is protected from the magnetic recording medium. Therefore, the reliability is further improved.

Next, an end surface of the sensor holding portion is formed perpendicular to the detection direction, and a rotation support having a surface which is in parallel with the end surface of the holding portion and a spherical surface which is rotatable substantially at the center of the sensor detection portion. And a connecting portion for connecting the sensor holding portion to the relative moving portion via the rotating support portion, the sensor holding portion having a plate surface in contact with the spherical portion of the rotating support portion. Even if the posture is tilted, the rotation is performed at the center of the sensor detection unit via the rotation support unit, so that no error occurs.

The spring may be of a compression type or a tension type as long as it exerts a force so that the above-mentioned structure comes into close contact. Movement of the sensor holding portion and the connecting portion in a direction perpendicular to the detection direction due to an attachment error or the like is allowed by slipping of the end surface of the sensor holding portion and the plane parallel to the rotation support portion. The connecting portion is finally fixed to the relative moving portion using a connecting portion mounting hole or the like.

In another configuration, the end surface of the sensor holding portion is integrally formed as a spherical surface centered on the substantially center of the sensor detecting portion, and a free surface having a plate surface in contact with the spherical surface and a surface perpendicular to the detecting direction is provided. The same effect can be obtained even in a configuration in which the connecting portion for connecting the sensor holding portion to the relative moving portion via the free supporting portion has a flat surface in contact with the flat portion of the free supporting portion. can get. When the attitude of the sensor holding unit is inclined, the sensor holding unit rotates while the spherical surface of the end surface contacts the plate surface of the free support unit.

Since the free supporting portion is pressed only by the spring and is not fixed, it can be moved in a direction perpendicular to the detecting direction, so that the allowable mounting range of the connecting portion is large and no error occurs. The spring may be of a compression type or a tension type as long as it exerts a force so that the above-mentioned structure comes into close contact.

The sensor holding portion is formed integrally with a sensor mounting portion, a bearing portion, a protection portion for the sensor detection surface, and a function for coping with a change in posture.

As the material, a non-magnetic material must be used to slide the magnetic recording medium. The material is
For example, a resin or a non-magnetic metal may be used. The resin material is not particularly limited, but those having excellent lubricity per se, such as polyacetal and polyamide, are preferred.

As the non-magnetic metal, a material such as beryllium copper or an austenitic material can be used. If a hardness is required, a thermosetting treatment may be performed. Further, a ceramic material may be used.

The non-magnetic material described above is also desirable for the material of the universal support portion. For example, if the inner diameter of the universal support portion is sufficiently large with respect to the diameter of the magnetic recording medium, the universal support portion will not be magnetically recorded. Since it does not come into contact with the medium, in such a case, it is not necessary to stick to the nonmagnetic material.

The sensor support structure for a magnetic linear encoder according to the present invention has a structure in which a sensor mounting portion, a bearing portion, and a protection portion of a sensor detection portion are integrated to form a holding portion, and there is no error with respect to a change in posture. Can be achieved.

Since the sensor mounting portion and the bearing-like support portion are integrally formed, the clearance between the bearing portion and the sensor mounting portion can be set in advance to a desired value and uniformly. Thereby, when the sensor is mounted on the holding portion and the magnetic recording medium is passed through the bearing portion, a minute and uniform gap can be automatically secured between the two, and
Since this gap is constituted by the holding section, there is no possibility that foreign matter enters the gap and breaks the sensor detecting section.

Further, the mounting error of the linear encoder
There are several factors that cause a change in the attitude of the holding unit, such as vibration and bending of the magnetic recording medium. However, since the sensor detection center can be used as the rotation center, no error occurs due to the attitude change.

As described above, the magnetic linear encoder constructed according to the present invention can easily be improved in assemblability, environmental resistance, accuracy, and mountability with a minimum number of parts. .

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a position detecting device according to the present invention will be described below with reference to FIGS.

Embodiment 1 FIGS. 1, 2, and 3 are explanatory views showing examples in which protection of a sensor mounting surface, a bearing unit, and a sensor detection unit are integrally formed and combined with a magnetic recording medium. In FIG. 1, the magnetic recording medium 1 has a rod-like shape (in cross section, the magnetic field N-pole and the magnetic field S-pole are recorded in the longitudinal direction as NS, SN, NS, SN). (Formed of a circle, a square, etc.).

The sensor 2 is a magnetic field sensing element, which is a magnetoelectric element (for example, a magnetoresistive element, a magnetic impedance element, a Hall element, etc.), and detects a magnetic field magnetized by the magnetic recording medium 1. This is to convert the information on the detected magnetic field into an electric signal.

As can be seen from FIG. 1, the sensor holding section 3 has a bearing 21 for fixing the sensor 2 and sliding on the magnetic recording medium 1.

Here, the detecting section 9 of the sensor 2 is fixed at a position corresponding to the bearing section 21 of the sensor holding section. That is, in the sensor holding unit 3 for mounting the sensor 2, a mounting surface is provided with reference to the sensor detection surface, and the magnetic recording medium 1 is positioned at a position where the gap between the sensor 2 and the magnetic recording medium 1 becomes a predetermined value. If a bearing is provided with a hole through which the magnetic recording medium 1 passes, a linear encoder can be formed.

As can be seen from FIG. 1, the bearing 21 is set to have the same width as the sensor detector 9. That is, W1 in the figure indicates the width of the sensor detecting section 9, and W indicates the bearing section 21.
It shows the width of. Here, W1 ≒ W.

As described above, FIG. 1 shows the bearing portion 21 formed with a minimum length necessary for regulating the clearance between the sensor 2 and the magnetic recording medium 1. Here, since the length of the bearing portion 21 is short, there is an advantage that machining of a hole in the bearing portion is easy.

The sensor 2 is joined to the sensor holder 3 by fitting or bonding, or fixed by a leaf spring or the like.

FIG. 2 shows an example in which the bearing portion 21 is set to have the same width as the sensor width. W2 in the figure is the sensor 2
It shows the width of. Here, W2 ≒ W.

FIG. 3 shows an example in which the bearing 21 is set to have a width larger than the sensor width. Here, W> W
It is 2.

As can be seen from FIGS. 1, 2 and 3, the range of the length of the bearing 21 in the sliding direction is
Is included. In the example of FIGS. 2 and 3,
Since the length of the bearing portion 21 is equal to or greater than the width of the sensor 2, not only can the clearance between the sensor 2 and the magnetic recording medium 1 be stably regulated, but also the entire sensor 2 can be sufficiently protected from mechanical shock and the like. It has the effect of.

As shown in FIGS. 1, 2, and 3, a part of the sensor holding portion always exists between the sensor detecting surface and the magnetic recording medium 1, and functions as a protective material. . X1 in the figure indicates the thickness.

As described above, according to the present embodiment, the sensor 2 and the magnetic recording medium 1
Is regulated, so that a stable and reliable clearance can be secured. Further, since the sensor holding portion 3 can be formed integrally, the number of components can be reduced. Further, since the sensor detecting section 9 is not exposed to the outside, it is possible to prevent a situation in which dust such as a foreign substance adheres to the surface of the sensor detecting section 9.
The slidability is further improved by chamfering the end surface of the bearing portion 21.

Embodiment 2 FIGS. 4, 5, and 6 are explanatory views of a configuration according to the present invention for actually connecting the sensor holding section 3 to a moving section of an object to be measured.

In FIG. 4, since the magnetic recording medium 1 cannot be fixed by itself, it must be attached to a fixing member (scale bracket). 4, a case will be described in which a scale bracket having a hole through which the magnetic recording medium 1 is passed, a bracket mounting hole, and a screw portion for pressing and fixing the magnetic recording medium 1 is used.

The magnetic recording medium 1 can be easily fixed by passing the magnetic recording medium 1 through the scale bracket and pressing it with a push screw. Further, if the pressing is performed via the auxiliary member (sleeve), the mounting can be performed more stably. The scale bracket is fixed with screws and bolts using the bracket mounting holes. This fixing may be performed after the magnetic recording medium 1 is attached to the scale bracket, or the magnetic recording medium 1 may be fixed after fixing first. Further, the magnetic recording medium 1 may be fixed while applying tension. In any case,
The method is not limited as long as it does not move in the detection direction.

In the sensor holding unit 3 as well, there is no flexibility, and if it is directly mounted, the sliding resistance at the time of detection increases, the bearing unit 21 wears quickly, and good position detection cannot be performed. Therefore, it is necessary to support the sensor holder 3 with flexibility.

In FIG. 4, the sensor holding section 3 has one end face 18 formed of a plane perpendicular to the sliding direction, and this end face 18 is rotatable about the sensor detecting section 9 as a center. 4 is pressed against the flat surface portion 19.

That is, the end face of the sensor holding part 3 is formed perpendicular to the detection direction, and a surface which is in parallel with the end face of the sensor holding part 3 and a spherical surface which is rotatable about the center of the sensor detecting part 9 are formed. Rotating support portion 4 having rotation supporting portion 4
A connecting portion 5 having a dish surface 16 in contact with the spherical surface 17 for connecting the sensor holding portion 3 to the relative moving portion via the rotation support portion 4 is brought into close contact with the force of a spring 6.

The spring 6 presses the end face of the sensor holding section 3 which is not in contact with the rotation supporting section 4. However, as shown in the drawing, a convex section is provided on this face so that the spring can be easily attached. Good. The connecting portion 5 is finally fixed to the relative moving portion using a connecting portion mounting hole or the like.

In this configuration, for example, even if the attitude of the sensor holding section 3 is inclined, the rotation is performed around the sensor detecting section 9 and no error occurs. In addition, the movement in the direction perpendicular to the detection direction due to an attachment error or the like of the sensor holding unit 3 and the connecting unit is allowed by slipping of the end surface of the sensor holding unit and the flat portion of the rotation support unit. Therefore, the configuration according to the present invention can cope with any change in the attitude of the sensor 2 and does not cause an error.

Also in this embodiment, the detection section of the sensor is fixed at a position corresponding to the bearing section of the sensor holding section.
The fact that the range of the length of the bearing portion in the sliding direction includes the detection portion of the sensor is the same as in the first embodiment, which is extremely effective. However, these are not indispensable requirements. Regardless of the shape of the portion, the present embodiment has the above-described effects.

FIG. 5 shows an example in which the magnetic recording medium 1 performs magnetic recording over the entire circumference of a cross section perpendicular to the sliding direction. That is, FIG. 5 shows a state where the mounting position of the sensor 2 is changed. If magnetic recording is performed on the entire circumference of the magnetic recording medium 1, the magnetic recording medium 1 may be arranged at any position on the circumference. For this reason,
Since the setting position of the sensor 2 can be freely selected, there is an effect that the assembly becomes easy.

FIG. 6 shows that the sensor holding section 3 has two end faces consisting of planes perpendicular to the sliding direction, and these end faces are two rotation support sections rotatable about the sensor detection section. 4 shows an example in which the flat portions 19 and 19 are pressed and held by the flat portions 19 and 19, respectively.

That is, in FIG. 6, the rotation supporting parts 4 and 4 are provided on the end face of the sensor holding part 3. By adopting such a configuration, there is an effect that the rotational movement of the sensor holding unit 3 becomes smoother and the stability is further improved.

Third Embodiment FIGS. 7, 8, 9 and 10 are explanatory diagrams of an example in which the configuration is changed from that of the second embodiment. FIG. 7 shows that the sensor holding unit 3
An example is shown in which one end surface consisting of a spherical surface 17 having a sensor detection portion as a center is provided, and this end surface 17 is pressed against the plate surface 16 of the free support portion 31 movable vertically to the sliding direction. Things.

That is, in FIG. 7, the end face of the sensor holding section 3 is formed integrally with a spherical surface 17 centered on the approximate center of the sensor detecting section 9 and is perpendicular to the detection direction with the dish surface 16 in contact with the spherical surface 17. A universal supporting portion 31 having a surface and a connecting portion 5 for connecting the sensor holding portion 3 to the relative moving portion via the universal supporting portion having a flat surface in contact with the flat portion 32 of the universal supporting portion 31 include a spring 6. Are brought into close contact by the force of

As shown in FIG. 8, when the attitude of the sensor holding section 3 is inclined, the sensor holding section 3 rotates while the spherical surface of the end face and the dish surface of the free support section 31 are in contact with each other. Swivel support 3
1 is only fixed by being pressed by a spring and is not fixed, so that it can be moved in a direction perpendicular to the detection direction, so that the attachment allowable range of the connecting portion is large and no error occurs.

The sensor holding section is formed integrally with a sensor mounting section, a bearing section, a protection section for the sensor detection surface, and a function for coping with a change in posture.

Also in this embodiment, the detecting section of the sensor is fixed at a position corresponding to the bearing section of the sensor holding section.
The fact that the range of the length of the bearing portion in the sliding direction includes the detection portion of the sensor is the same as in the first embodiment, which is extremely effective. However, these are not indispensable requirements. Regardless of the shape of the portion, the present embodiment has the above-described effects.

FIG. 9 shows an example in which the magnetic recording medium 1 performs magnetic recording over the entire circumference of a cross section perpendicular to the sliding direction. That is, FIG. 9 shows a state where the mounting position of the sensor 2 is changed. If magnetic recording is performed on the entire circumference of the magnetic recording medium 1, the magnetic recording medium 1 may be arranged at any position on the circumference. For this reason,
Since the setting position of the sensor 2 can be freely selected, there is an effect that the assembly becomes easy.

FIG. 10 shows that the sensor holding section 3 has two ends 17 and 17 each having a spherical surface with the sensor detecting section being substantially at the center, and these end faces can be freely moved perpendicularly to the sliding direction. The respective plate surfaces 16, 1 of the support portion 31 and the pressing member 7
6 shows an example in which the pressure-contact is held.

That is, FIG. 10 shows a configuration in which spherical surfaces 17, 17 having the center substantially at the center of the sensor detector 9 are provided at both ends of the sensor holding unit. By adopting such a configuration, there is an effect that the rotational movement of the sensor holding unit 3 becomes smoother and the stability is further improved.

As described above, according to the present embodiment, the sensor holding portion 3 is integrally formed with the bearing portion 21 for keeping the gap between the sensor mounting portion and the magnetic recording medium 1 constant and the protection of the sensor detection surface. As a result, a minute and uniform gap between the magnetic recording medium 1 and the sensor 2 as a sensor can be easily secured without requiring a precise adjustment work as in the prior art, and at the same time, the magnetic detection unit formed of a thin film Can also be configured.

Further, since the function of suppressing the occurrence of errors due to the change in the attitude of the sensor 2 is formed integrally with the sensor holding section 3, it is possible to have a simple component configuration and the freedom to have no error with respect to the attitude change. it can.

As described above, the magnetic linear encoder constructed according to the present invention has a high precision, assemblability, environmental resistance,
The mountability is improved and can be achieved with a minimum number of parts.

The present invention may be a semi-unit type as shown in FIG. 4 or a unit type in which the magnetic recording medium 1 and the sensor 2 are housed in a housing as shown in FIG.

Further, the present invention is not limited to the above-described embodiment, but can adopt various other configurations without departing from the gist of the present invention.

[0070]

As described above, according to the present invention,
The sensor holding part is formed integrally with the bearing part to keep the gap between the sensor mounting part and the magnetic recording medium constant, and the protection of the sensor detection surface is easily formed. Moreover, a uniform gap can be secured,
At the same time, a portion for protecting the magnetic detection portion formed of a thin film can be configured.

In addition, since the function of suppressing the occurrence of errors due to the change in the attitude of the sensor is integrally formed with the sensor holding section, it is possible to provide a simple component structure and have no error with respect to the attitude change.

Further, the position detecting device constructed according to the present invention is improved in accuracy, assembling property, environmental resistance and mounting property, and can be achieved with a minimum number of parts.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a sensor holding unit according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a case where a length of a bearing unit is configured to be equal to a width of a sensor according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a case where a bearing according to an embodiment of the present invention is configured to have a width equal to or larger than a width of a sensor;

FIG. 4 is a diagram illustrating a configuration of a position detection device according to an embodiment of the present invention.

FIG. 5 is a diagram showing a case where the direction of the sensor is changed in the example of FIG. 4;

FIG. 6 is a diagram showing a case where the configuration of pressing is changed in the example of FIG. 4;

FIG. 7 is a diagram illustrating a configuration of a position detection device according to an embodiment of the present invention.

FIG. 8 is a diagram showing an example when the posture of the sensor holding unit changes according to the embodiment of the present invention.

FIG. 9 is a diagram showing a case where the direction of the sensor is changed in the example of FIG. 7;

FIG. 10 is a diagram illustrating a case where the pressing configuration is changed in the example of FIG. 7;

FIG. 11 is a diagram showing an example of a unit type position detecting device according to an embodiment of the present invention.

FIG. 12 is a diagram provided for describing a conventional position detection device.

FIG. 13 is a diagram provided for describing a conventional position detecting device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Magnetic recording medium, 2 sensors, 3 sensor holding parts, 4
Rotation supporting part, 5 connecting part, 6 spring, 7 pressing member,
Reference Signs List 8 flexible substrate, 9 sensor detecting unit, 10 protective cover, 11 leaf spring, 12 housing, 13 magnetic recording medium holding unit, 14 housing mounting surface, 15 connecting unit mounting surface, 16 dish surface, 17 spherical surface, 18 holding unit End face, 19
Rotary support flat surface, 20 Connecting part mounting hole, 21 Bearing part, 22 Sensor mounting surface (sensor detection surface), 23 Cable, 24 Scale bracket, 25 Bracket mounting hole, 26 Sleeve, 27 dust lip, 28
Fixing pin, 29 Housing part mounting bolt, 30 Push screw, 31 Free support part, 32 Free support part flat part

Claims (6)

[Claims] 1. A rod-shaped magnetic recording medium in which N and S poles are arranged and recorded in a longitudinal direction thereof, and a magneto-electric conversion element (hereinafter, referred to as a magnetic-electric conversion element) which senses a magnetic field magnetized in the magnetic recording medium and converts the magnetic field into an electric signal. , "Sensor"), and a sensor holding portion having a bearing portion that slides on the magnetic recording medium, wherein the detecting portion of the sensor corresponds to the bearing portion of the sensor holding portion. A position detection device fixed to a position, wherein a detection portion of the sensor is included in a range of a length of the bearing portion in a sliding direction. 2. A bar-shaped magnetic recording medium in which N and S poles are arranged and recorded in a longitudinal direction thereof, and a sensor for detecting a magnetic field magnetized in the magnetic recording medium and converting the magnetic field into an electric signal are fixed. And a sensor holding part having a bearing part that slides on the magnetic recording medium, wherein the sensor holding part has one end face made of a plane perpendicular to the sliding direction, and this end face is A position detecting device which is in pressure contact with a plane portion of a rotation supporting portion rotatable about a sensor detecting portion as a center. 3. A rod-shaped magnetic recording medium in which N and S poles are arranged and recorded in a longitudinal direction thereof, and a sensor for detecting a magnetic field magnetized in the magnetic recording medium and converting the magnetic field into an electric signal are fixed. And a sensor holding unit having a bearing unit that slides on the magnetic recording medium, wherein the sensor holding unit has two end faces consisting of a plane perpendicular to the sliding direction, and these end faces Is pressed and held between two flat portions of two rotation supporting portions rotatable about a sensor detecting portion. 4. A rod-shaped magnetic recording medium in which N and S poles are arranged and recorded in a longitudinal direction thereof, and a sensor which detects a magnetic field magnetized in the magnetic recording medium and converts the magnetic field into an electric signal are fixed. And a sensor holding portion having a bearing portion that slides on the magnetic recording medium, wherein the sensor holding portion has one end surface formed of a spherical surface having a center substantially at the sensor detection portion. A pressure detecting device that is pressed against a plate surface of a free supporting portion movable vertically to a sliding direction. 5. A bar-shaped magnetic recording medium in which N and S poles are arranged and recorded in a longitudinal direction thereof, and a sensor which detects a magnetic field magnetized in the magnetic recording medium and converts the magnetic signal into an electric signal. And a sensor holding unit having a bearing unit that slides on the magnetic recording medium, wherein the sensor holding unit has two end surfaces each formed of a spherical surface having the sensor detection unit as a center. A position detecting device characterized in that an end face is pressed and held by respective plate surfaces of a free supporting portion and a pressing member which are movable in a direction perpendicular to a sliding direction. 6. The magnetic recording medium according to claim 1, wherein magnetic recording is performed over the entire circumference of a cross section perpendicular to the sliding direction.
The position detecting device according to 2, 3, 4, or 5.