JPH03137530A - Displacement sensor and torque sensor - Google Patents

Abstract

PURPOSE:To measure accurately only the displacement in a prescribed direction by putting a slider having a magnet in one body with a second member and by putting it in one body with a first member having a sensor main body fixed thereto in directions other than the prescribed. CONSTITUTION:A slider 11 is held in a groove 15a provided in a projecting part 15 of a sensor main body 12 so that it can move forward and backward only along the groove 15a. Projections 10a and 10b of a sleeve 7 hold the slider 11 along the direction of rotation of the sleeve 7 and a force of rotation is not transmitted to the slider even when the sleeve 7 rotates with an input shaft 2 and an output shaft 3. Accordingly, displacement in the axial direction of the sleeve 7 rotating with the output shaft 3 is found by chip-shaped magnets 14a and 14b in the slider 11. When a torque is equal, the opposed relationship between a Hall element 16 and the magnets 14a and 14b is unvaried. In this constitution, a complicated structure and an expansive member are dispensed with and a construction is inexpensive. In addition, zero-point adjustment of a displacement sensor is also facilitated by fitting of a projection 12a of a torque sensor 12 in a round hole 1a of a housing 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to improvements in non-contact displacement sensors and torque sensors that utilize magnetic flux density detection elements such as Hall elements and magnetoresistive elements and magnets.

[Conventional technology]

This type of conventional technology includes, for example, Japanese Utility Model Application Publication No. 60-179944, which was previously proposed by the present applicant, and Japanese Utility Model Application Publication No. 64
There is one disclosed in Japanese Patent No.-10638.

These conventional technologies relate to a torque detector that detects torque generated around a shaft, and connect an input shaft and an output shaft rotatably supported by a housing through an elastic body such as a torsion bar. A magnet is fixed to a moving member that converts the relative rotation between the input shaft and the output shaft that occurs with the twisting of the body into axial displacement, and the axial displacement occurs, and a magnetic flux density detection element is installed on the housing side. This configuration includes a sensor body having a sensor body.

With such a configuration, relative rotation occurs between the input shaft and the output shaft according to the torque generated around the shaft, and that relative rotation is converted into axial displacement of the moving member, and the magnet fixed to the moving member Since the relative position between the sensor body and the sensor body provided on the housing side changes, the magnetic flux density received by the magnetic flux density detection element of the sensor body fluctuates. Therefore, based on the magnetic flux density detected by the magnetic flux density detection element, the moving direction and amount of movement of the moving member, that is, the direction and magnitude of torque are detected.

In the above conventional technology, a cylindrical member surrounding the shaft is used as the moving member, and a ring-shaped magnet that fits around the moving member is used as the magnet, so that the input shaft and the output shaft are connected to the housing. Even when the sensor body is rotated relative to the sensor body, the relative positional relationship between the sensor body and the magnet does not change. In other words,
Even if the input shaft and output shaft simply rotate relative to the housing, if the magnetic flux density of the ring-shaped magnet is uniform over the entire circumference and there is no installation error, the magnetic flux received by the magnetic flux density detection element will be Since no change occurs, only the relative rotation between the input shaft and the output shaft, that is, the torque can be detected.

[Problem to be solved by the invention]

However, in the above conventional technology, a ring-shaped magnet is used for the above-mentioned reason, but it is a part of the ring-shaped magnet that actually provides magnetic flux to the magnetic flux density detection element, so In order to eliminate any effect of the rotation of the output shaft relative to the housing on the detected value, the magnetic flux density of the ring-shaped magnet must be uniform across the entire circumference, so that there is no uneven magnetization, as described above. Furthermore, when installing a ring-shaped magnet, errors (eccentricity or inclination with respect to the axis) will affect the measured value of the magnetic flux density detection element, so high precision is required in the assembly work. The shaped magnet is larger than the chip shaped magnet, and the ring shaped magnet (
In particular, magnets with poles in the radial direction) are difficult to generate strong (high magnetic flux density), so in order to obtain sufficient performance, rare earth magnets with high magnetic flux density must be used, although they are expensive. Therefore, the device becomes expensive.

There are also sensors that include a sensor body and a magnet on the housing side and measure displacement by moving the magnet with a rod or lever depending on the relative displacement, but the disadvantage is that the displacement transmission structure and seal structure are complicated. There is.

The present invention was made by focusing on the unresolved problems of the conventional technology, and provides a displacement sensor and a ring-shaped magnet that have a simple configuration and can measure displacement only in a predetermined direction. It is an object of the present invention to provide a torque sensor that can eliminate the influence of rotational phase without using.

(Means for Solving the Problem) In order to achieve the above object, the displacement sensor according to claim (1) is a displacement sensor that detects relative displacement in a predetermined direction between the first and second members. A sensor body having a magnetic flux density detection element is fixed to the first member, a slider having a magnet is arranged between the sensor body and the second member, and the slider is moved in the predetermined direction. is provided with movement direction control means that is integrated with the second member and integrated with the first member in directions other than the predetermined direction.

Further, the displacement sensor according to claim (2) is provided with the above-mentioned claim (
1) In the displacement sensor described above, the movement direction control means 11 includes a first guide provided on the first member or the sensor body and receiving the slider along the predetermined direction; and a second guide provided on the member and receiving the slider along a direction perpendicular to the predetermined direction.

Furthermore, in order to achieve the above object, the torque sensor according to claim (3) connects a human power shaft and an output shaft rotatably supported by a housing through an elastic body, and connects the human power shaft and the output shaft between the human power shaft and the output shaft. a moving member that is provided with a displacement converting means for converting relative rotation into an axial linear displacement, a sensor body having a magnetic flux density detection element is fixed to the housing, and a slider having a magnet is moved in the axial direction by the displacement converting means. and the sensor body, further comprising a movement direction control means for making the slider integral with the moving member in the axial direction and integral with the housing in directions other than the axial direction.

The torque sensor according to claim (4) is the torque sensor according to claim (3), in which the moving direction control means is provided on the housing or the sensor body and is arranged along the axial direction on the slider. The first step is to accept
and a second guide provided on the moving member and receiving the slider along the periphery of the axis.

[Effect]

In the displacement sensor according to claim (1), when a relative displacement occurs between the first and second members, the slider disposed between the sensor body and the second member is moved by the movement direction control means. , is integral with the second member in the predetermined direction and is integral with the first member in directions other than the predetermined direction, so there is no relative displacement between the first and second members in directions other than the predetermined direction. Even if this happens, the relative displacement that occurs between the first member and the slider is only a relative displacement in a predetermined direction. Therefore, from the measurement value of the magnetic flux density detection element, only the relative displacement in a predetermined direction between the first and second members is measured.

In the displacement sensor according to claim (2), when a relative displacement occurs between the first and second members, the relative displacement in the predetermined direction is caused by moving the second guide from the second member. The movement of the slider with respect to the first member at that time is guided by the first guide provided on the first member side, and the relative displacement in a direction other than the predetermined direction is The signal is transmitted from one member to the slider via the first guide, and the movement of the slider relative to the second member at that time is guided by the second guide. In the end, only relative displacement in a predetermined direction occurs between the first member and the slider, so the measured value of the magnetic flux density detection element indicates only relative displacement in a predetermined direction between the first and second members. be measured.

In addition, in the torque sensor according to claim (3), when torque is transmitted to the input shaft and the output shaft connected via the elastic body, there is a difference in the direction of the torque between the input shaft and the output shaft. and a relative rotation depending on the size.

Then, the displacement converting means converts the relative rotation into an axial displacement of the moving member, so there is no relative displacement in the axial direction between the moving member and the housing that supports the input and output shafts. arise.

The slider disposed between the sensor main body provided in the housing and the moving member is controlled by the moving direction control means to be integral with the moving member in the axial direction and in a direction other than the axial direction (for example, around the axis). Since the slider is integral with the housing, even if a relative displacement occurs between the housing and the moving member in a direction other than the axial direction, the relative displacement that occurs between the housing and the slider is only the relative displacement in the axial direction. Therefore, even if the input shaft and output shaft rotate with respect to the housing and the moving member rotates with respect to the sensor body,
From the measurement value of the magnetic flux density detection element, only the relative displacement in the axial direction between the housing and the moving member, that is, the relative rotation between the input shaft and the output shaft that occurs depending on the direction and magnitude of the torque is measured.

Further, in the torque sensor according to claim (4), the relative displacement in the axial direction is transmitted from the starting member to the slider via the second guide, and the movement of the slider with respect to the housing at that time is caused by the movement toward the housing. The relative displacement in a direction other than the axial direction is transmitted from the housing side to the slider via the first guide, and the movement of the slider with respect to the moving member at that time is guided by a second guide. In the end, only relative displacement in the axial direction occurs between the housing and the slider, so from the measurement value of the magnetic flux density detection element, only the relative rotation between the input shaft and output shaft occurs depending on the direction and magnitude of torque. is measured.

〔Example] Embodiments of the present invention will be described below based on the drawings.

1 and 2 are diagrams showing a first embodiment of the present invention, and this is an example in which a displacement sensor and a torque sensor according to the present invention are applied to an electric power steering device for a vehicle.

First, to explain the configuration, in FIG. 1, in a housing 1 as a first member, an input shaft 2 and an output shaft 3 are connected via a torsion bar 4 as an elastic body.
It is rotatably supported by bearings 5a, 5b, and 5C. However, input shaft 2, output shaft 3 and torsion bar 4
are arranged coaxially.

A steering wheel is integrally attached to the right end side in FIG. 1 (not shown) of the input shaft 2 in the rotation direction, and a known rack and pinion steering device, for example, is attached to the left end side in FIG. The binion shafts constituting the are connected.

Therefore, the steering force generated by the driver steering the steering wheel is applied to the input shaft 2° torsion bar 4. The signal is transmitted to steered wheels (not shown) via the output shaft 3 and the rack and pinion steering device.

Further, an axially continuous protrusion 2a is formed on the outer peripheral surface of the left end of the input shaft 2, and this protrusion 2a is formed on the right end of the output shaft 3 and is wider than the protrusion 2a. vertical groove 3a
is inserted into the input shaft 2 and output shaft 3.
Relative rotation beyond a predetermined range (approximately ±5 degrees) between the two is prevented.

A gear 6 that rotates coaxially and integrally with the output shaft 3 is externally fitted onto the output shaft 3. Not connected to the output shaft of the electric motor.

Furthermore, a cylindrical sleeve 7 as a second member or a moving member is fitted onto the input shaft 2 and is movable relative to the input shaft 2 in the axial and rotational directions. A vertical groove 7a formed at the left end of the sleeve 7 has a pin 3 that is press-fitted into the right end of the output shaft 3 and protrudes radially outward.
The outer end of b is inserted.

Therefore, the output shaft 3 and the sleeve 7 are integral in the rotational direction, but can be relatively displaced in the axial direction within the length range of the vertical groove 7a.

The sleeve 7 is always urged to the right in FIG. It is accommodated in a V-shaped spiral groove 2b formed on the outer peripheral surface of.

Furthermore, protrusions 10a and 10b are formed on the outer circumferential surface of the sleeve 7 as continuous second guides over the entire circumference. In addition, each of the mutually opposing surfaces of these protruding bodies 1Oa and 10b is formed parallel to a plane orthogonal to the axis.

A slider ll is provided between the protruding bodies 10a and 10b.
is disposed, and a housing l facing the slider 11 is provided.
The axial position of the slider 11, that is, the housing l
A sensor body 12 for detecting relative displacement in the axial direction between the slider 11 and the slider 11 is fixed.

The slider 11 includes a main body 11a made of a non-magnetic material.
A thin plate-shaped yoke 13 and a yoke 13 spaced apart in the axial direction.
It contains two chip-shaped magnets 14a and 14b fixed to the inside.

The magnets 14a and 14b are arranged in the radial direction (Fig. 1, vertical direction).
For example, one magnet 14a has an N pole on the yoke 13 side and an S pole on the sensor body 12 side, and the other magnet 14b has an S pole on the yoke 13 side and an N pole on the sensor body 12 side. By doing so, the polarities are opposite to each other. however,
Magnets 14a and 14b are equidistant from the axial center of slider 11.

FIGS. 2(a) to 2(C) are views showing the external appearance of the sensor body 12. FIG. 2(a) is a bottom view of the sensor body 12, and FIG. 2(C) is a direction B in FIG. A view in the direction of arrows, (C) is a view in the direction of arrow C in (a) of the same figure.

As shown in FIGS. 1 and 2 (a) to (C), the sensor main body 12 has a disc-shaped fitting portion 12a formed on its bottom surface that fits into the round hole 1a of the housing l. At the same time, the fitting portions 1a are formed on the flanges 12b and 12c.
Long holes 12d and 12e curved concentrically with
It is fixed to the housing 1 by bolts (not shown) passing through 2d and 12e.

Further, a convex portion 15 serving as a first guide is integrally formed on the fitting portion 12a.

The convex portion 15 is arranged in the axial direction (second direction) of a disk having the same diameter as the fitting portion 12a.
The shape is obtained by cutting both ends of the figure (a) in the vertical direction) along a plane perpendicular to the axis, and its width (in the vertical direction in figure 2 (a)).
is formed shorter than the axial dimension of the slider 11 described above.

The convex portion 15 is formed with a groove 15a that is long in the axial direction and into which the slider 11 is inserted so as to be freely advanced and retracted, and the central axis of the groove 15a is parallel to the axis of the sleeve 7. It is spaced apart from the central axis of the fitting part 12a.

In this embodiment, since the cross-sectional shape of the slider 11 is T-shaped, the groove 15a is also a T-shaped groove in accordance with the T-shaped cross section. Therefore, the slider 11 can only move in the axial direction (left-right direction in FIG. 1) with respect to the sensor body 12.

Furthermore, both end surfaces 11b and li of the slider 11 in the axial direction
e forms concentric circular arcs, and their end faces 11
b. The circle generated by IIC has a diameter approximately equal to the distance between the protrusions 10a and 10b formed on the sleeve 7.

A Hall element 16 as a magnetic flux density detection element is built into the sensor body 12 so as to face the center between the magnets 14a and 14b in the slider 11.

Note that an electronic circuit is configured within the sensor body 12 to supply a predetermined current to the Hall element 16, measure the output voltage of the Hall element 16, and supply the measurement result to a controller (not shown). Furthermore, the controller to which the measurement results have been supplied calculates the steering torque of the steering system based on the measurement results, and drives and controls the electric motor (not shown) described above according to the calculated steering torque. Steering assist torque is generated on the output shaft 3 via the gear 6.

Next, the operation of the above embodiment will be explained.

Now, assuming that the steering system is in a straight-line state and the steering torque is zero, there is no relative rotation between the input shaft 2 and the output shaft 3, so the sleeve 7 rotates integrally with the output shaft 3.
No relative rotation occurs between the input shaft 2 and the input shaft 2, either. Therefore, since the ball 9 remains at a predetermined position within the spiral groove 2b, no advancing or retracting force is generated on the sleeve 7, and as a result, the slider 11 is also at a predetermined position in the axial direction.

Therefore, since the Hall element 16 maintains a state facing the center of the magnets 14a and 14b, the density of the magnetic flux received by the Hall element 16 does not change, and the controller to which the measured value of the Hall element 16 is supplied can control the steering. Obtain the calculation result that the torque is zero. Therefore, since the electric motor is not driven, no steering assist torque is generated in the steering system, and the steering system maintains the straight traveling state.

When a rotational force is generated on the input shaft 2 by steering the steering wheel, the rotational force is transmitted to the output shaft 3 via the torsion bar 4.

At this time, a resistance force is generated on the output shaft 3 according to the frictional force between the steered wheels and the road surface, the frictional force of the rack and pinion type steering device configured on the left end side (not shown) of the output shaft 3, and so on. 2 and the output shaft 3, a relative rotation occurs between the output shaft 3 and the output shaft 3 due to the torsion bar 4 being twisted.

Then, the sleeve 7 that is integrated with the output shaft 3 in the rotation direction
Also, relative rotation with respect to the input shaft 2 occurs, but the sleeve 7
Since the ball 9 accommodated in the hole 7b on the inner surface of the input shaft 2 is accommodated in the helical groove 2b on the outer peripheral surface of the input shaft 2, the sleeve 7 moves forward and backward in the axial direction according to the inclination angle of the helical groove 2b.

Note that it is necessary to provide a slight gap between the ball 9, the spiral groove 2b, and the inner surface of the hole 7b so that the ball 9 can move, but the spring 8 biases the sleeve 7 in one direction. Therefore, the sleeve 7 is prevented from wobbling due to the gap.

When the sleeve 7 moves back and forth, the slider 11 interposed between the projecting bodies 10a and 10b integral with the sleeve 7 also moves in the axial direction, so the relative positions of the magnets 14a, 14b and the Hall element 16 change.

Therefore, the density of the magnetic flux that the Hall element 16 receives changes,
Since the output value of the Hall element 16 changes accordingly,
The controller determines the direction and magnitude of the steering torque based on the output value, and drives the electric motor to rotate so that the gear 6 rotates in a direction in which the steering torque decreases.

Then, since the steering assist torque is applied to the output shaft 3, the steering torque is reduced and the burden on the operator can be reduced.

With the configuration of the above embodiment, the slider 11 is
Since it is received in the groove 15a provided in the protrusion 15 of the sensor body 12, it can move forward and backward only along the groove 15a, and the protrusion 1 provided in the sleeve 7 can move forward and backward only along the groove 15a.
0a and 10b receive the slider 11 along the direction of rotation of the sleeve 70, so even if the sleeve 7 rotates together with the input shaft 2 and output shaft 3, the rotational force is transferred to the slider 1.
I can't tell it to 1.

That is, the slider 11 moves integrally with the sleeve 7 in the axial direction, but the housing 1 moves in a direction other than the axial direction. It is integrated with the sensor body 12.

Therefore, the chip-shaped magnet 14a inside the slider 11
and 14b, the axial displacement (steering torque) of the sleeve 7 rotating together with the output shaft 3 can be measured.

Chip-shaped magnets are smaller than ring-shaped magnets, so even if rare earth magnets are used to improve performance, the magnets do not become extremely expensive. Since the opposing relationship between magnet 16 and magnets 14a and 14b is constant, eccentricity or inclination of the magnet with respect to the axis, or non-uniformity of magnetic flux density in the circumferential direction, unlike ring-shaped magnets, does not affect the measured value.

Furthermore, with the configuration of the above embodiment, since the movement of the slider 11 is controlled by the protrusions 10a, 10b and the groove 15a that receive the sleeves, no particularly complicated structure or expensive members are required. , it is possible to have an inexpensive configuration.

Note that in order to accurately calculate the steering torque in the controller, when the steering torque is at a low level, that is, when the sleeve 7 is not moving forward or backward in the axial direction, the Hall element 16 moves between the magnets 14a and 14b. Although it is desirable that they face each other in the center, there are many cases where this cannot be achieved due to dimensional errors or installation errors of each part.

In order to eliminate such problems, in this embodiment, when fixing the sensor main body 12 to the housing 1, the following zero point adjustment is performed.

That is, the groove 15a into which the slider 11 is inserted and the Hall element 16 are in contact with the center of the fitting part 12a, and both end surfaces 11b and llc of the slider 11 are in contact with the protruding body 1.
A circular arc is formed which is approximately equal to the distance between 0a and 10b.

Therefore, when the sensor 12 is rotated with the fitting part 12a of the sensor body 12 fitted into the round hole 1a of the housing l, the Hall element 16 rotates around the center of the fitting part 12a. Although the axial position changes, the slider 11 moves back and forth within the groove 15a while moving the protrusions 10a and 10.
b, the centers of both magnets 14a and 14b always remain aligned with the center between protrusions 10a and 10b. Therefore, the relative positional relationship between the axial center between the magnets 14a and 14b and the axial position of the Hall element 16 gradually changes as the sensor body 12 rotates.

Therefore, the output of the controller is monitored and the sensor body 1 is
2 to rotate the center between both magnets 14a and 14b,
A rotational position of the sensor 12 that matches the axial position of the Hall element 16 is searched, and the sensor body 12 is fixed to the housing at the matching position using the elongated holes 12d and 12e of the flanges 12b and 12c. .

In other words, even if there is a slight error in the dimensions of each member, the zero point adjustment of the displacement sensor (torque sensor) can be easily performed. ) Since there is no need to use members, etc., an increase in the cost of the device is suppressed.

Here, in the above embodiment, the protrusions 10a, 10b, the groove 1
5a constitutes a moving direction control means, and the spiral groove 2b
, bottle 3b, vertical groove 7a, hole 7b.

Spring 8. The balls 9 constitute displacement converting means.

Next, a second embodiment of the present invention will be described.

FIG. 3 is a diagram showing a second embodiment of the present invention, which is an example in which the present invention is applied to a power steering device for a vehicle, similar to the first embodiment. Note that the same parts and members as in the first embodiment are designated by the same reference numerals, and redundant explanation thereof will be omitted.

That is, in this embodiment, a magnetoresistive element 20 is used as a magnetic flux density detection element, and a thin plate made of a ferromagnetic material is provided in the sensor body 12 so as to be in contact with the surface of the magnetoresistive element 20 on the opposite side from the sleeve 7. The structure of the sensor main body 12 is the same as that of the first embodiment, except for the arrangement of the yoke 21.

Further, the structure of the slider 11 is such that instead of the yoke 13 and the magnets 14a, 14b in the first embodiment, a main body 11a is used.
The second embodiment is the same as the first embodiment except that a chip-shaped magnet 14c is buried so that the surface facing the sensor body 12 is exposed. However, the magnet 14c has poles in the vertical direction in the figure.

Furthermore, this embodiment differs from the first embodiment in the configuration of the displacement converting means that converts the relative rotation between the input shaft 2 and the output shaft 3 into axial displacement of the sleeve 7.

That is, as shown in FIG. 3, a shaft 23 is provided at the right end of the output shaft 3 and is supported by bearings 22a and 22b and is rotatable about an axis perpendicular to the input shaft 2. The center portion of the pin 24 is curved to avoid collision with the input shaft 2, and one end of a pin 24 extending parallel to the input shaft 2 is press-fitted into a predetermined position in the axial direction.

The other end of the pin 24 is inserted into a vertical groove 20 formed in the input shaft 2, and a curved portion (not shown) of the shaft 23 is integrally provided with a shaft extending in a direction perpendicular to the shaft 23. , the tip of the shaft is connected to the sleeve 7 via a swingable joint.

Incidentally, vertical grooves 7c and 7d are formed in the sleeve 7 to avoid collision with the shaft 23 when the sleeve 7 moves back and forth.

Therefore, when a relative rotation occurs between the input shaft 2 and the output shaft 3, the shaft 23 rotates together with the output shaft 3, so that there is also a relative rotation between the input shaft 2 and the shaft 23 in the rotation direction of the input shaft 2. Rotation occurs.

Then, since the vertical groove 20 of the input shaft 2 and the shaft 23 are connected via the pin 24 press-fitted into the shaft 23, the pin 24 rotates around the axis of the shaft 23.

As a result, the shaft 23 rotates, so the shaft 23
The tip of a shaft provided integrally with the curved portion (not shown) swings, and the sleeve 7 connected to the shaft moves forward and backward in the axial direction.

Here, in this second embodiment, the vertical groove 2c, the bearing 22a,
22b, shaft 23. The pin 24 constitutes displacement converting means.

Furthermore, in this second embodiment, since the yoke 21 is disposed on the back side of the magnetoresistive element 20, most of the magnetic flux generated by the magnet 14c becomes orthogonal to the magnetoresistive element 20. , measurement accuracy can be increased.

Other functions and effects are the same as those of the first embodiment.

In each of the above embodiments, the protrusions 10a, 10b and the groove 15a constitute the moving direction control means, but the structure of the means is not limited to this. For example, the sleeve 7 of the slider 11 A long groove or protrusion is provided in the circumferential direction of the sleeve 7 on the surface facing the side, and a protrusion or groove is provided on the outer peripheral surface of the sleeve 7 that matches the groove or protrusion and continues in the circumferential direction. , on the surface of the slider 11 facing the sensor main body 12 side, a groove or protrusion long in the direction of movement of the sleeve 7 is provided, and a protrusion or groove that is aligned with the groove or the protrusion and long in the direction of movement of the sleeve 7 is provided. If it is provided on the surface of the sensor body 12 facing the sleeve 7 side, the same effect as in each of the above embodiments can be obtained.

Furthermore, in each of the above embodiments, a case is explained in which a Hall element or a magnetoresistive element is used as the magnetic flux density detection element, but the magnetic flux density detection element is not limited to these, and other types may be used. You can.

Further, in each of the above embodiments, the displacement sensor and torque sensor of the present invention are applied to an electric power steering device for a vehicle, but the present invention is not limited to this.

Furthermore, the displacement converting means is not limited to the configuration of the first or second embodiment described above, and other known configurations may be applied.

The number of magnets and magnetic flux density detection elements to be used is not limited to those in the above embodiments, and for example, a configuration may be adopted in which a plurality of magnetic flux density detection elements are used.

〔Effect of the invention〕

As explained above, according to the displacement sensor according to claim (1), the slider having the magnet is integrated with the second member in a predetermined direction, and the sensor main body is integrated in a direction other than the predetermined direction. Since it is configured to be integrated with the fixed first member, the relative displacement that occurs between the first member and the slider is only in the predetermined direction, so only the displacement in the predetermined direction can be accurately measured. It has the effect of being able to

According to the displacement sensor according to claim (2), since a complicated structure and expensive members are not required, it is possible to have an inexpensive configuration.

Further, according to the torque sensor according to claim (3), the slider having the magnet is integrated with a moving member that moves forward and backward in the axial direction according to the relative rotation between the input shaft and the output shaft, and Since the sensor body is integrated with the fixed housing in directions other than the direction, the relative displacement that occurs between the sensor body and the slider is only the displacement in the axial direction according to the torque. Even if the moving member rotates, the measured value is not affected by the rotation, so that only the torque can be accurately measured.

According to the torque sensor described in claim (4), since a complicated structure and expensive members are not required, it is possible to have an inexpensive configuration.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the configuration of the first embodiment of the present invention, and FIG.
Figures (a) to (C) are external views showing an example of the sensor body, with figure (a) being a bottom view and figure (b) being figure (a).
FIG. 2C is a view taken in the C direction of FIG. 1A. FIG. 3 is a sectional view showing the structure of a second embodiment of the present invention. 1... Housing (first member), 2... Input shaft,
2b... spiral groove, 2C... vertical groove, 3... output shaft,
4... Torsion bar (elastic body), 7... Sleeve (second member, moving member), 7a... Vertical groove, 7b...
・Hole, 8...Spring, 9...Ball, 10a,
10b...Protruding body (second guide), 11...Slider, 12...Sensor body, 14a, 14b, 1
4c... Magnet, 15... Convex portion (first guide), 1
5a... Groove, 16... Hall element (magnetic flux density detection element), 20... Magnetoresistive element (magnetic flux density detection element),
22a, 22b...Bearing, 23...Shaft, 24
···bottle.

Claims (4)

[Claims] (1) A displacement sensor that detects relative displacement in a predetermined direction between a first and a second member, in which a sensor body having a magnetic flux density detection element is fixed to the first member, and a slider having a magnet. is disposed between the sensor body and the second member, and further, the slider is integral with the second member in the predetermined direction and is integral with the first member in a direction other than the predetermined direction. A displacement sensor comprising integrated movement direction control means. (2) The movement direction control means is provided on the first member or the sensor body and includes a first guide that receives the slider along the predetermined direction, and a first guide that is provided on the second member and the sensor body. 2. The displacement sensor according to claim 1, further comprising a second guide for receiving the slider along a direction orthogonal to a predetermined direction. (3) An input shaft and an output shaft rotatably supported by the housing are connected via an elastic body, and a displacement converting means is provided for converting the relative rotation between the input shaft and the output shaft into linear displacement in the axial direction, A sensor body having a magnetic flux density detection element is fixed to the housing, a slider having a magnet is disposed between the sensor body and a movable member that is moved in the axial direction by the displacement converting means, and the slider is further moved along the axis. A torque sensor comprising a moving direction control means that is integrated with the moving member in the direction and integrated with the housing in directions other than the axial direction. (4) The movement direction control means includes a first guide that is provided on the housing or the sensor body and receives the slider along the axial direction, and a first guide that is provided on the moving member and receives the slider along the axial direction. 4. The torque sensor according to claim 3, further comprising a second guide for receiving the slider.