JP6540285B2 - Stroke sensor - Google Patents

Description

  The present invention relates to a stroke sensor.

As a stroke sensor which detects the moving amount | distance of mobile bodies, such as a lever of a motor vehicle or a two-wheeled vehicle, there exist some which were disclosed by patent document 1, for example.
The stroke sensor includes a shaft that follows the movement of the object to be detected, a housing that houses the shaft, a cap that is disposed to close one end of the housing and that supports the sliding of the penetrating shaft, and the shaft A magnet provided at the other end, a magnetic detection element provided in the housing for detecting a change in the magnetic field of the magnet, and an origin return mechanism for returning the shaft to the origin position after the shaft reciprocates; The amount of movement in the axial direction is detected by the change of the magnetic field.

German Patent Application Publication No. 102010015036

However, in the stroke sensor described in Patent Document 1, since the sliding portion supporting the shaft is constituted by the inner peripheral surface of the cap portion closing one end of the housing, the supporting width of the sliding portion is shorter than the entire shaft length. Also, because the magnet is placed at the tip of the shaft, if the mounting center of the magnet deviates from the shaft center, the detection gap between the magnet and the magnetic detection element fluctuates with the movement of the shaft, and detection accuracy There is a problem of falling.
In addition, if the center of attachment of the magnet and the center of the shaft deviate, the shaft is strongly hit on a part of the sliding portion, and there is a problem that local wear is likely to occur.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a stroke sensor that can improve detection accuracy and can reduce local wear.

In order to achieve the above object, a stroke sensor according to the present invention is
A stroke sensor that detects the amount of movement of a detection shaft that follows an object to be detected and reciprocates in the axial direction centering on a home position,
The detection shaft is configured by axially connecting a first shaft of nonmagnetic material and a second shaft of magnetic material,
A first housing made of a nonmagnetic material that regulates the rotation of the detection shaft and slidably supports the first shaft; and a second housing made of a metal material that houses the second shaft A housing having
An origin return mechanism using a metal material , provided between the second shaft and the second housing , for detecting the movement amount and returning the detection shaft to the origin position;
A magnet provided on a side surface of the first shaft ;
And a magnetic detection element provided in the first housing so as to face the magnet and detecting the amount of movement from a change in magnetic field accompanying movement of the detection shaft.
It is characterized by

  According to the present invention, detection accuracy can be improved and local wear can be reduced.

It is the top view which shows one Embodiment of the stroke sensor of this invention, AA sectional drawing, and BB sectional drawing. It is sectional drawing of the 1st shaft of one embodiment of this invention. It is sectional drawing of the 2nd shaft of one embodiment of this invention. It is sectional drawing of the 1st housing of one embodiment of this invention. It is sectional drawing of the 2nd housing of one embodiment of this invention. It is sectional drawing of the origin return mechanism of one embodiment of this invention.

Hereinafter, a stroke sensor according to an embodiment of the present invention will be described based on the attached drawings.
The stroke sensor 1 according to the present invention is, as shown in FIG. 1, a stroke sensor 1 for detecting the amount of movement of the detection shaft 10 that reciprocates around the origin position O following the object to be detected. A housing 20 which restricts rotation and is slidably supported, and an origin return mechanism which is provided between the detection shaft 10 and the housing 20 and returns the detection shaft 10 after detection and movement amount of movement to the origin position O A magnet 40 provided on the side surface of the detection shaft 10, and a magnetic detection element 50 provided on the housing 20 opposite the magnet 40 to detect the amount of movement from a change in the magnetic field accompanying the movement of the detection shaft 10; It is configured to have.

The detection shaft 10 according to the present embodiment is a detection medium which is tracked by the movement of the detection object, and is connected to the detection object, for example, to transmit an external force, and reciprocates in the axial direction to follow.
The detection shaft 10 is comprised by the 1st shaft 11 and the 2nd shaft 12, as shown to FIGS. 1-3, and the 1st shaft 11 and the 2nd shaft 12 are connected with the screw.

The first shaft 11 is made of a nonmagnetic metal having a certain degree of rigidity, and is typically made of austenitic stainless steel (SUS; Steel Use Stainless).
The first shaft 11 is configured to include three large diameter portions 11a having different diameters, a middle diameter portion 11b, and a small diameter portion 11c.
The small diameter portion 11c protrudes outward from the housing 20 (the first housing 21), and is formed with, for example, an external thread 11d in order to connect with the detected body, and is connected with the detected body by a screw to follow.
The large diameter portion 11a and the middle diameter portion 11b are disposed in the housing 20 (first housing 21), and their rotation is restricted by a sliding support portion 23 described later with the housing 20 (first housing 21). Is supported so that it can slide.
The large diameter portion 11a has an internal thread portion 11e for connecting to the second shaft 12 on the end surface opposite to the small diameter portion 11c. Furthermore, a centering groove 11f for securing the position of the second shaft 12 and the centering state with the first shaft 11 is formed concentrically in the outer peripheral portion of the female screw portion 11e on the end face of the large diameter portion 11a. is there. By forming this centering groove 11f, the center of the second shaft 12 and the center of the first shaft 11 are aligned with high accuracy on the inner peripheral surface of the centering groove 11f, and the annular flat end face of the second shaft 12 The tightening position can be held in place and connected.
Thereby, the eccentricity with respect to the 1st shaft 11 by the load of the spring 31c added to the 2nd shaft 12 mentioned later can be suppressed as much as possible.
The end surface outside the centering groove 11f of the end surface of the large diameter portion 11a is made a locking portion 11g of the piston 31a of the home position return mechanism 30 described later, and when the first shaft 11 is pushed, a pushing force is applied to the piston 31a. introduce.
As a result, a reaction force is generated by the spring 31c via the piston 31a, and the first shaft 11 can be returned to the home position O.
Further, the large-diameter portion 11a is formed with a notch surface 11h whose side surface is flatly cut at the end opposite to the small-diameter portion 11c, and the cross-sectional shape is substantially D-shaped.
The axial length of the first shaft 11 of the notch surface 11 h is equal to or slightly longer than the detection stroke S. The rotation of the first shaft 11 is restricted by the cutaway surface 11 h in cooperation with the sliding support portion 23 of the housing 20 (first housing 21) described later.
The radially inner portion 11 b is formed with the magnet housing portion 11 i in the radial direction on the side surface. The magnet 40 is stored in the magnet storage portion 11i and fixed by an adhesive or the like.

The second shaft 12 is connected to the first shaft 11 to form a detection shaft 10, and is housed in the housing 20 (second housing 22).
For example, a metal material is used for the second shaft 12. Similar to the first shaft 11, the second shaft 12 is preferably a nonmagnetic material, but since the distance to the magnet 40 is secured, even if it is a soft magnetic material such as steel, the degree of influence on the magnetic field is It is possible to select an appropriate material in light of cost and strength.
The second shaft 12 is configured to include three large diameter portions 12a having different diameters, a middle diameter portion 12b, and a small diameter portion 12c.
In the small diameter portion 12c, a male screw 12d is formed, and a stepped portion 12e is formed between the male screw 12d and the middle diameter portion 12b.
Thereby, the second shaft 12 and the first shaft 11 are connected by the male screw portion 12 d and the female screw portion 11 e of the first shaft 11, and the step portion 12 e is tightened so as to fit in the centering groove 11 f of the first shaft 11 Thus, they are connected in a centered state and at a predetermined axial position. At the time of connection, loosening of the screw is prevented with a reinforcing adhesive (for example, a sealock agent) or the like.
The middle diameter portion 12b is formed in a cylindrical shape having a predetermined axial length, and pistons 31a and 31b and a spring 31c of an origin return mechanism 30 described later are mounted.
The large diameter portion 12 a constitutes a locking portion 12 f of a piston 31 b of an origin return mechanism 30 described later, and forms a pair with the locking portion 11 g of the piston 31 a of the first shaft 11. The large-diameter portion 12 a has, for example, a hexagonal shape around the outer periphery, and can be turned by a tool such as a wrench at the time of connection with the first shaft 11.

The housing 20 is, as shown in FIGS. 1, 4 and 5, connected to the first housing 21 in which the first shaft 11 is mainly accommodated, and the first housing 21 and the second shaft 12 is mainly accommodated. 2 and a housing 22 are comprised.
The first housing 21 is formed of a nonmagnetic material in a substantially cylindrical shape, and is made of, for example, a metal material such as aluminum or stainless steel, or a synthetic resin material such as PBT (Poly Butylene Terephthalate) or PPS (Poly Phenylene Sulfide) Used. A large diameter hole portion 21a, a middle diameter hole portion 21b, and a small diameter hole portion 21c are continuously formed in the inner peripheral portion of the first housing 21, and the middle diameter hole portion 21b and the small diameter hole portion 21c are formed. The sliding support 23 of the first shaft 11 is configured.
In the large diameter hole portion 21a, a female screw portion 21d is formed in the middle portion of the inner peripheral surface, and the second housing 22 is connected by a screw. The circumferential surface 21e and the end face 21f formed on the tip end side (inner diameter hole portion 21b side) of the female screw portion 21d are fitted with the second housing 22 in the large diameter hole portion 21a, and centering and connection position in the axial direction Set
Further, the end face 21 f of the large diameter hole 21 a is a contact surface of the piston 31 a of an origin return mechanism 30 described later.
As shown in FIGS. 1 and 4, the middle diameter hole 21 b is formed in a substantially D-shaped cross section in contact with the outer surface of the notch surface 11 h of the large diameter portion 11 a of the first shaft 11. Is formed to have a sufficient axial length even if the first shaft 11 moves by the detected stroke S of the first shaft 11.
The small diameter hole portion 21 c is formed to have an inner diameter that allows the middle diameter portion 12 b of the first shaft 11 to slide.
As a result, the rotation of the first shaft 11 around the central axis is restricted by the substantially D-shape and the small-diameter hole portion 21c of the middle-diameter hole portion 21b constituting the slide support portion 23 of the housing 20. , Is supported so that the sliding for the detection stroke S is performed with high accuracy.
Therefore, the rotation of the first shaft 11 is substantially restricted by the first housing 21 and the first shaft 11 is slidably supported.
The first housing 21 is formed with a substrate storage portion 21 g of the circuit board 51 on which the magnetic detection element 50 is mounted to face the magnet storage portion 11 i of the first shaft 11. The board storage portion 21g is a rectangular recess having a bottom surface parallel to the notch surface 11h of the first shaft 11, and is projected upward from the bottom surface to temporarily fix the positioning pins 21h of the circuit board 51 and the circuit board 51. An internal thread 21i for the screw is formed. By providing female screw portions 21i for screws for temporarily fixing the positioning pins 21h and the circuit board 51 in the board housing portion 21g, the magnetic detection element 50 mounted on the circuit board 51 can be the first with a gap as small as possible with respect to the magnet 40. It can be fixed to the housing 21 and the change of the magnetic field by the magnet 40 can be detected with high accuracy.

The second housing 22 is connected to the first housing 21 to constitute the housing 20, and for example, a metal material is used. Similar to the first housing 21, the second housing 22 is preferably a nonmagnetic material, but since the distance to the magnet 40 is secured, the degree of influence on the magnetic field can be obtained even with a soft magnetic material such as steel. It is possible to select an appropriate material in light of cost and strength.
As shown in FIGS. 1 and 5, the second housing 22 is formed in a cylindrical shape with an outer shape of approximately two steps, and includes a large diameter portion 22a and a small diameter portion 22b.
A male thread 22c is formed on the outer periphery of the middle portion of the large-diameter portion 22a, and the centering portion in which the outer peripheral portion 22d on the distal end side of the male thread 22c and the front end surface 22e are fitted to the peripheral surface 21e and the end surface 21f of the first housing 21 As. As a result, the male screw 22c of the second housing 22 and the female screw portion 21d of the first housing 21 can be tightened and connected at a predetermined position in the axial direction in a centered state.
A cylindrical large-diameter hole 22f and a small-diameter hole 22g are continuously formed on the inner peripheral side of the large-diameter portion 22a, and the large-diameter hole 22f serves as the pistons 31a and 31b and the spring 31c of the origin return mechanism 30. It becomes piston storage part 31d to store. The small diameter hole portion 22 g is a storage space for the large diameter portion 12 a of the end portion of the second shaft 12.
Further, the step surface 22h between the large diameter hole 22f and the small diameter hole 22g is a contact surface of the piston 31b of the origin return mechanism 30 described later.
The small diameter portion 22b is formed with a female screw portion 22i from the outer end face to the central portion, and is used to be held on a detection target to be subjected to stroke detection.
The second housing 22 is not limited to a metal material, and the screw portion may be insert-molded on a synthetic resin material as the metal material.

The origin return mechanism 30 is, as shown in FIGS. 1 and 6, a pair of pistons 31a and 31b, and a spring 31c mounted between the two pistons 31a and 31b and urging them to separate from each other. Configured
For example, a metal material is used for the two pistons 31a and 31b. The two pistons 31a and 31b are preferably nonmagnetic materials, but since the distance to the magnet 40 is secured, even if they are soft magnetic materials such as steel materials, the degree of influence on the magnetic field is low, and It is possible to select an appropriate material in light of the strength.
The two pistons 31a and 31b are formed in a cylindrical shape with a bottom, and a mounting hole for mounting on the middle diameter portion 12b of the second shaft 12 is formed at the center of the bottom portion.
The two pistons 31a and 31b are opposed to each other with their bottom portions facing outward, and are slidably mounted on the middle diameter portion 12b of the second shaft 12, and a spring 31c constituted by a coil spring is interposed between the two pistons 31a and 31b. It is mounted and mounted on the second shaft 12.
The two pistons 31a and 31b are slidably disposed in the large-diameter hole 22f (piston storage portion 31d) of the second housing 22 formed by connecting the first housing 21 and the second housing 22.

  The spring 31c is formed of a coil spring made of stainless steel, for example, SUS304WPB. The spring 31c is preferably made of a nonmagnetic metal such as stainless steel (for example, SUS304WPB), but since there is a distance to the magnet 40, even a soft magnetic material (for example, SWB or SWC) is a magnetic field. Since the degree of influence is low, materials may be selected as appropriate in view of durability and strength.

As shown in FIG. 1, the two pistons 31a and 31b of the origin return mechanism 30 at the origin position O have the outer surface of the piston 31a (the outer surface of the bottom of the bottomed cylinder) the larger diameter hole 21a of the first housing 21. When the outer surface (the outer surface of the bottom of the bottomed cylinder) of the other piston 31b abuts on the step surface 22h of the large diameter hole 22f of the second housing 22, the separation distance is restricted. Ru. Then, the separation distance (interval) between the cylindrical portions of the two pistons 31a and 31b in this state (origin position O) is the detection stroke S of the detection shaft 10 (see FIG. 6).
Further, at the origin position O, the outer surface of the piston 31a (the outer surface of the bottom of the bottomed cylinder) abuts on the locking portion 11g which is the end surface of the large diameter portion 11a of the first shaft 11, and the other piston 31b The outer surface (the outer surface of the bottom of the bottomed cylinder) is in contact with the end surface of the large diameter portion 12a of the second shaft 12 on the first shaft 11 side.

  In the origin return mechanism 30, when the detection shaft 10 at the origin position O is displaced so as to be pushed into the housing 20, the outside of the piston 31a via the locking portion 11g which is an end face of the large diameter portion 11a of the first shaft 11. The side surface (the outer surface of the bottom of the bottomed cylinder) is pushed in, and the other piston 31b can not move in contact with the step surface 22h of the large diameter hole portion 22f of the second housing 22, and the two pistons 31b resist the spring 31c. It can move by the detection stroke S until the cylindrical part of piston 31a, 31b hits. Then, when the force pressing the detection shaft 10 disappears, the detection shaft 10 is returned to the home position O by the spring force accumulated in the spring 31 c.

In the home position return mechanism 30, when the detection shaft 10 at the home position O is displaced so as to be pulled out from the housing 20, the outer surface of the piston 31b (the outer surface of the bottom of the bottomed cylinder) is the diameter of the second shaft 12 The end of the large part 12a is pulled out via the end face on the first shaft 11 side, and the outer surface of the piston 31a (the outer surface of the bottom of the bottomed cylinder) abuts on the end face 21f of the large diameter hole 21a of the first housing 21 and moves It can not move and can move only the detection stroke S until the cylindrical portion of the two pistons 31a and 31b abut against the spring 31c. Then, when the force for pulling out the detection shaft 10 disappears, the detection shaft 10 is returned to the home position O by the spring force accumulated in the spring 31 c.
A lubricant such as grease is applied to the outer peripheral surface of the piston accommodating portion 31d in which the pistons 31a and 31b are accommodated, to ensure stable long-term sliding.

The magnet 40 is formed of a rare earth based magnet (for example, a magnet of a material such as SmCo or NdFeB) formed in a quadrangular prism shape or a cylindrical shape.
In the present embodiment, the magnet 40 has a cylindrical shape using a SmCo sintered magnet, and two poles are magnetized in the vertical direction (magnet thickness direction) which is the long axis direction.
The magnet 40 is housed in the magnet housing portion 11i of the first shaft 11 of the detection shaft 10 and fixed by an adhesive or the like.
The magnet 40 provides a magnetic field to the magnetic detection element 50 facing the magnet 40 of the first housing 21, and the direction (magnetic force) of the magnetic field applied to the magnetic detection element 50 by the magnet 40 being displaced together with the detection shaft 10 As a result, the magnetic detection element 50 detects the movement amount.
The magnet 40 may be any of a sintered magnet and a plastic magnet mixed with a plastic and compressed or molded by a manufacturing method.
The sintered magnet has a stronger magnetic force, while the plastic magnet has characteristics such as high mass productivity and high crack resistance. Therefore, it may be selected appropriately according to the use conditions and design requirements.

The magnetic detection element 50 detects a displacement such as the amount of movement of the object to be detected, and is formed of, for example, a Hall element, and converts a change in magnetic force accompanying the displacement such as the movement of the object to be detected into an electrical signal. Output to the outside.
For example, the magnetic detection element 50 is configured as a magnetic detection package by mounting a plurality of Hall elements on the circuit board 51.
Here, the detection surface of the magnetic detection element 50 of the magnetic detection package is disposed in the direction perpendicular to the magnetization direction of the magnet 40. The magnetic detection package provided with the magnetic detection element 50 stores the circuit board 51 in the board storage portion 21g of the housing 20 (first housing 21), temporarily fixes the positioning pin 21h and the female screw portion 21i with a screw, It is airtightly held by the sealing member and the lid. By doing this, the gap with the magnet 40 is made as small as possible so that the change of the magnetic field can be detected with high accuracy.
The power supply to the magnetic detection element 50 of the magnetic detection package and the output to the outside are performed by a direct connector or a cord.
The magnetic detection element 50 may be mounted on a wire frame or the like to form a magnetic detection package.
The detection of the stroke S in the magnetic detection package 9 using the magnetic detection element 50 is performed by a plurality of Hall elements of the circuit board 51 and horizontal to the magnetic field in the direction perpendicular to the magnetic detection surface of the magnetic detection element 50 formed by the magnet 40. Detect the direction of the magnetic field. The obtained two-direction magnetic fields in the vertical direction and horizontal direction are converted into angles by a trigonometric function (ATAN) in a processing circuit (for example, ASIC; Application Specific Integrated Circuit), and output as angle information. The output angle information and the amount of movement (stroke S) of the detection shaft 10 are proportional, and as a result, the amount of movement of the detection shaft 10 can be detected.
Also, the output system from the magnetic detection package including the magnetic detection element 50 may be any system, and may be selected according to a control unit (ECU; Engine Control Unit) or the like that uses the detection result ( For example, analog, Pules Width Modulation (PWM), Single Edge Nibble Transmission (SENT), and the like.

According to such a stroke sensor 1, since the detection shaft 10 is slidably supported by the rotation of the sliding support portion 23 of the housing 20, the support width for the entire length of the detection shaft 10 is increased. The contact area can be increased and supported, and the detection shaft 10 can be slid relative to the housing 20 in a stable manner.
Thus, the gap between the magnet 40 attached to the detection shaft 10 whose rotation is restricted and the magnetic detection element 50 attached to the housing 20 can be made as small as possible, and a change in the magnetic field can be detected with high accuracy. Further, by attaching the magnet 40 to the side surface of the detection shaft 10, a small magnet 40 can be formed, and the magnetic field can be concentrated to detect a stroke from a large change.
Further, by sliding the detection shaft 10 with respect to the housing 20 without rotating, there is no swing of the detection shaft 10 having a large contact area, and it is possible to prevent part of the detection shaft 10 from strongly hitting the housing 20. The occurrence of local wear can be prevented to improve the durability.
Further, since the magnet 40 and the magnetic detection element 50 serving as the magnetic detection portion are concentrated on one side of the detection shaft 10 and the housing 20 and the origin return mechanism 30 is arranged on the other side, By making one side into a nonmagnetic material, even if the other side is made of a magnetic metal material, it is possible to detect the change in the magnetic field while minimizing the influence on the magnetic field. Thereby, durability can be improved by making the origin return mechanism 30 into a metal material.
Further, by dividing the iron-based material into non-magnetic and magnetic on one side and the other side of the detection shaft 10 and the housing 20 described above, the peripheral part of the magnet 40 can be made a non-magnetic material to suppress the influence of magnetic field change. And the other side can increase the freedom of choice of material.

  According to the stroke sensor 1 of the present invention, the stroke sensor 1 detects the amount of movement of the detection shaft 10 that reciprocates around the origin position O following the object to be detected, and restricts the rotation of the detection shaft 10 A housing 20 slidably supported, and an origin return mechanism 30 provided between the detection shaft 10 and the housing 20 for detecting the amount of movement and returning the detection shaft 10 to the origin position O after movement. Since the magnet 40 provided on the side surface of the detection shaft 10 and the magnetic detection element 50 provided on the housing 20 opposite to the magnet 40 and detecting the amount of movement from the change in the magnetic field accompanying the movement of the detection shaft 10 The detection accuracy can be improved by the small gap magnet 40 and the magnetic detection element 50, and the rotation is restricted and the detection shaft that slides is contacted by the housing 20. By supporting increasing the product, it is possible to reduce local wear. Further, the gap between the magnetic detection element 50 attached to the housing 20 and the magnet 40 of the detection shaft 10 can be reduced, gap fluctuation can be suppressed and disturbance of the magnetic field can be reduced, and change of the magnetic field can be detected with high accuracy. it can.

  Further, according to the stroke sensor 1, the detection shaft 10 is configured of the first shaft 11 of nonmagnetic material and the second shaft 12 of magnetic material coupled to the first shaft 11, and the first shaft 11 is The supporting first housing 21 is made of a nonmagnetic material, so that the materials used can be divided between the first shaft 11 and the first housing 21 and the second shaft 12 and the second housing 22, for example, By separating the iron-based material from non-magnetic and magnetic, the influence of the magnetic field change can be suppressed with the peripheral portion of the magnet 40 as the non-magnetic material, and the detection accuracy can be improved.

  Further, according to the stroke sensor 1, the second shaft 12, the second housing 22 for housing the second shaft 12, and the origin return mechanism 30 housed in the second housing are made of metal material, so that the magnetism is achieved. It is possible to suppress the influence on the detection part and make the used material a material in consideration of durability and strength, and it is possible to more reliably improve the durability and strength.

  In the above embodiment, although the detection shaft 10 is configured by connecting the first shaft 11 and the second shaft 12, it is configured by a single shaft and only the large diameter portion 12a of the second shaft 12 is formed. You may make it attach with a screw etc. In this case, it is preferable to provide a positioning groove so as to enable axial positioning.

Reference Signs List 1 stroke sensor 10 detection shaft 11 first shaft 11a large diameter portion 11b small diameter portion 11c small diameter portion 11d male screw portion 11e female screw portion 11f centering groove 11g locking portion 11h cutaway surface 11i magnet storage portion 12 large diameter second shaft 12a large diameter 12b diameter middle portion 12c diameter small portion 12d male screw 12e stepped portion 12f locking portion 20 housing 21 first housing 21a large diameter hole portion 21b small diameter hole portion 21c small diameter hole portion 21d internal thread portion 21e peripheral surface 21f end surface 21g substrate storage portion 21h positioning Pin 21i Female screw 22 Second housing 22a Large diameter 22b Small diameter 22c Male thread 22d Outer peripheral surface 22e Tip surface 22f Large diameter hole 22g Diameter small hole 22h Step surface 22i Female screw 23 Slide support 30 Origin return mechanism 31a Piston 31b Piston 31c Spring 31d Piston storage part 40 Magnet 50 Magnetism detection element 51 Circuit board O Origin position S Detection stroke

Claims (1)

A stroke sensor that detects the amount of movement of a detection shaft that follows an object to be detected and reciprocates in the axial direction centering on a home position,
The detection shaft is configured by axially connecting a first shaft of nonmagnetic material and a second shaft of magnetic material,
A first housing made of a nonmagnetic material that regulates the rotation of the detection shaft and slidably supports the first shaft; and a second housing made of a metal material that houses the second shaft A housing having
An origin return mechanism using a metal material , provided between the second shaft and the second housing , for detecting the movement amount and returning the detection shaft to the origin position;
A magnet provided on a side surface of the first shaft ;
And a magnetic detection element provided in the first housing so as to face the magnet and detecting the amount of movement from a change in magnetic field accompanying movement of the detection shaft.
A stroke sensor characterized by

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