Rotation detection device

Abstract

Improves durability. [Solution] The rotation detection device 100 has an insertion hole 32 into which a shaft member 101 is inserted, a rotating body 30 that rotates together with the shaft member 101, a ring member 20 that rotatably supports the rotating body 30, a leaf spring 31 that is provided in the insertion hole 32 and elastically supports the shaft member 101 inserted into the insertion hole 32, and a detection unit 52 that detects the rotation of the rotating body 30. In the axial direction of the rotation center C0 of the rotating body 30, the leaf spring 31 and the shaft member 101 abut against each other within a support range H0 of the rotating body 30 by the ring member 20.

Description

[Technical Field]

[0001] The present technology relates to a rotation detection device. [Background technology]

[0002] Conventionally, rotation detection devices that detect the rotation of a rotating body into which a shaft member is inserted are known. For example, in the devices disclosed in Patent Documents 1 and 2, the rotating body is rotatably supported on a support member and has an insertion hole. In these devices, a leaf spring is provided as an elastic member in the insertion hole of the rotating body, and the shaft member inserted into the insertion hole is urged in one direction against the side of the insertion hole by the urging force of the leaf spring, thereby holding the shaft member in the insertion hole. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-90769 [Patent Document 2] Japanese Patent Application Publication No. 2019-109173 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the devices of Patent Documents 1 and 2, there is a risk that variations will occur in the relative relationship between the position where the rotating body is supported by the support member and the position where the rotating body and the shaft member abut, depending on the workmanship of the rotation detection device and the mounting state of the shaft member. When such variations occur, a force acts on the rotating body in a direction that causes it to fall against the support member, which raises concerns about reduced durability due to eccentricity and uneven wear.

[0005] The purpose of this technology is to improve durability. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the rotation detection device of the present technology has a rotating body having an insertion hole into which an axial member is inserted and which rotates together with the axial member, a support member that rotatably supports the rotating body, an elastic member that is provided in the insertion hole and elastically supports the axial member inserted into the insertion hole, and a detection unit that detects the rotation of the rotating body, and the elastic member and the axial member abut within the support range of the rotating body by the support member in the axial direction of the rotation center of the rotating body. [Effects of the Invention]

[0007] According to the present technology, durability can be improved. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. [Figure 2] FIG. 2 is a cross-sectional view taken along line AA. [Figure 3] FIG. 2 is an exploded perspective view of a part of the rotation detection device. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present technology will be described with reference to the drawings.

[0010] Fig. 1 is a top view of a rotation detector according to an embodiment of the present technology, and Fig. 2 is a cross-sectional view taken along line AA in Fig. 1.

[0011] This rotation detection device 100 detects the rotation angle of an attached shaft member 101. The shaft member 101 is, by way of example, a rotating shaft mounted on a vehicle for detecting gear position, but is not limited to this. The rotation detection device 100 includes, as its main elements, a case 10, a ring member 20 (support member), a rotating body 30, a base member 40, and a sealing member 50.

[0012] FIG. 3 is an exploded perspective view of a portion of the rotation detector 100, showing the ring member 20, the rotor 30, the base member 40, and the like.

[0013] As shown in Fig. 1, case 10 has fixing hole 11 and signal extraction portion 12. Fixing hole 11 is fixed to a part of a vehicle that has shaft member 101. Hereinafter, the directions of each part will be referred to based on the X, Y, and Z coordinate axes shown in each figure. For convenience, the axial direction of rotation center C0 of rotating body 30 is defined as the Z direction, and in particular, the opening side of insertion hole 32 is defined as the +Z side.

[0014] The case 10, the rotor 30, the base member 40, and the sealing member 50 are made of resin, for example. The sealing member 50 is made of thermosetting resin, for example. The ring member 20 is made of metal such as stainless steel, and is provided integrally with the case 10 by insert molding, improving assembly ease. Note that the materials of each member are not limited to those exemplified.

[0015] The base member 40 is disposed on the −Z side of the rotating body 30 within the case 10 and is prevented from rotating with respect to the case 10. Therefore, the case 10, ring member 20, base member 40 and sealing member 50 are fixed to one another.

[0016] On the other hand, the rotating body 30 is disposed on the inner periphery of the ring member 20 and is rotatable around a rotation center C0. The rotating body 30 has an insertion hole 32 into which the shaft member 101 is inserted and rotates together with the shaft member 101. The ring member 20 is provided separately from the case 10. The ring member 20 has a hole 21 and supports the rotating body 30 within the hole 21. Therefore, the rotating body 30 is supported via the ring member 20 so as to be rotatable relative to the case 10.

[0017] A magnet 33 is held on the rotor 30 (FIGS. 2 and 3). A substrate 51 is fixed to the case 10 via a base member 40. A detection unit 52 is mounted on the substrate 51. Therefore, the case 10 holds the detection unit 52 via the base member 40. An electrical terminal 53 is connected to the substrate 51 and extends into the signal extraction unit 12.

[0018] The detection unit 52 detects the rotation of the rotor 30 from changes in magnetic flux. Specifically, the detection unit 52 is composed of, for example, a Hall sensor or an MR (magnetoresistive) sensor. When the magnet 33 rotates integrally with the rotor 30, the magnetic flux changes. From this change in magnetic flux, the rotation angle of the rotor 30, and therefore the rotation angle of the shaft member 101, is detected. The detection result of the rotation angle of the shaft member 101 is sent to the vehicle via the electrical terminal 53. Because the detection unit 52 does not come into contact with the rotor 30, this contributes to improved durability.

[0019] A leaf spring 31 is disposed within the insertion hole 32 as an example of an elastic member that elastically supports the shaft member 101. The shaft member 101 has a flat cutout portion (not shown) and is formed with a D-shaped cross section. The leaf spring 31 elastically presses against the cutout portion of the inserted shaft member 101. As a result, the shaft member 101 is supported within the insertion hole 32, and the rotating body 30 rotates integrally with the shaft member 101.

[0020] 2, the position where the leaf spring 31 and the shaft member 101 abut in the axial direction (Z direction) of the rotation center C0 of the rotating body 30 is defined as a contact position P1. In addition, the support range of the rotating body 30 by the ring member 20 in the axial direction of the rotation center C0 is defined as H0.

[0021] In the axial direction, the leaf spring 31 and the shaft member 101 abut against each other within a support range H0. In other words, the ring member 20 rotatably supports the rotating body 30 at least at a contact position P1 in the axial direction. In further other words, the ring member 20 rotatably supports the rotating body 30 at least in an imaginary cross section H1 that includes the contact position P1 and is perpendicular to the axis of the rotation center C0.

[0022] As a result, even if the contact position P1 varies slightly in the axial direction, the contact position P1 is located within the support range H0. Therefore, the support range H0 and the contact position P1 do not move apart in the axial direction, so at the contact position P1, no force acts on the rotating body 30 in a direction that would cause it to tilt relative to the axis. This prevents a decrease in durability due to eccentricity or uneven wear. The prevention of tilting and uneven wear also helps maintain the detection accuracy of the rotation angle.

[0023] When the rotor 30 rotates, it slides against the ring member 20. As described above, the ring member 20 is made of stainless steel or the like, which is harder than the case 10, ensuring the ring member 20's resistance to wear due to sliding.

[0024] The rotation detector 100 is generally manufactured as follows.

[0025] First, a worker obtains the case 10 with the ring member 20 fixed thereto by insert molding. The outer periphery of the ring member 20 may be knurled. Next, the worker inserts the rotating body 30 holding the magnet 33 into the hole 21 of the ring member 20 from the -Z side. The worker then attaches the leaf spring 31 to the insertion hole 32 of the rotating body 30. The leaf spring 31 may be attached either before or after the rotating body 30 is attached to the ring member 20.

[0026] Next, the worker inserts the base member 40 into the hole in the case 10 from the -Z side and fits it in place. Next, the worker places the substrate 51, which holds the detection unit 52, adjacent to the base member 40 and fixes it from the -Z side. Next, the worker supplies the sealing member 50 from the -Z side, fills the periphery of the substrate 51, and seals the substrate 51 by thermally curing it. The placement range of the sealing member 50 is restricted by an O-ring (not shown).

[0027] According to this embodiment, the leaf spring 31 and the shaft member 101 come into contact with each other within the support range H0 in the axial direction of the rotation center C0, thereby improving durability.

[0028] The ring member 20, which serves as a support member for rotatably supporting the rotor 30, is provided separately from the case 10. A different material from that of the case 10 can be used for the ring member 20; for example, by using a material harder than the case 10, the wear resistance of the ring member 20 can be increased. However, the present invention is not limited to this, and the case 10 itself may be configured to serve as a support member.

[0029] Furthermore, although the ring member 20 is provided integrally with the case 10, the present invention is not limited to this. For example, the ring member 20 may be supported rotatably relative to the case 10.

[0030] It should be noted that other elastic members may be used instead of the leaf spring 31, as long as the elastic member has the function of biasing the shaft member 101 in one direction relative to the rotor 30. For example, a coil spring, a steel wire bent into the same shape as the leaf spring 31, or rubber or the like may be used.

[0031] The present technology has been described above in detail based on preferred embodiments thereof, but the present technology is not limited to these specific embodiments, and various forms within the scope of the gist of the present technology are also included in the present technology. [Explanation of symbols]

[0032] 20 ring member, 30 rotating body, 31 leaf spring, 32 insertion hole, 52 detection portion, 100 rotation detection device, 101 shaft member, C0 rotation center, H0 support range

Claims

1. a rotating body having an insertion hole into which a shaft member is inserted and rotating together with the shaft member; a support member that rotatably supports the rotating body; an elastic member provided in the insertion hole and elastically supporting the shaft member inserted into the insertion hole; a detection unit that detects rotation of the rotating body, a rotation detection device in which the elastic member and the shaft member abut against each other within a support range of the rotating body by the support member in the axial direction of the rotation center of the rotating body;

2. The rotation detector according to claim 1 , wherein the support member rotatably supports the rotating body at least at a position in the axial direction where the elastic member and the shaft member abut against each other.

3. a case for holding the detection unit; The rotation detector according to claim 1 , wherein the support member is provided separately from the case and supports the rotor so as to be rotatable relative to the case.

4. The rotation detector according to claim 3 , wherein the support member is made of a material harder than that of the case.

5. 5. The rotation detector according to claim 4, wherein the support member is integrally provided in the case by insert molding.

6. a magnet held by the rotor; The rotation detection device according to claim 1 , wherein the detection unit detects the rotation of the rotating body from a change in magnetic flux.

Images