Rotating device and position sensor

Abstract

To provide a rotating device and a position sensor capable of preventing omission of a seal.SOLUTION: A rotating device includes: a shaft-shaped body extending in an axial direction; a case that has a shaft hole and rotatably supports the shaft-shaped body passed through the shaft hole; a seal for blocking a gap between a hole peripheral wall of the shaft hole and the shaft-shaped body from one side in the axial direction; and a seal presser that is fitted into the gap in a position of the one side in the axial direction rather than the seal position, and prevents movement of the seal from the other side in the axial direction to the one side in the axial direction. The hole peripheral wall has a press-fitted hole peripheral wall section into which the seal presser is press-fitted.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a rotating device and a position sensor.

Background Art

[0002] For example, Patent Document 1 discloses a position sensor including a shaft, a housing, a bearing disposed in a gap between the housing and the shaft for rotatably supporting the shaft, and a brush base connected to the shaft. The housing has a recess for accommodating the brush base, the recess is disposed on one side of the gap between the bearing and the shaft, a connector is fixed to the recess facing the brush base, a resistor substrate is fixed to the facing surface of the connector and the brush base, a part of a connection terminal is embedded in the connector, and one end of the terminal is connected to the resistor of the resistor substrate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the position sensor described in Patent Document 1, when foreign matter such as dust enters the recess through the above-mentioned gap, the measured value changes, so the measurement accuracy due to measurement error decreases. Therefore, in order to prevent the intrusion of foreign matter, it is conceivable to block the gap with a seal.

[0005] However, for example, there is a problem that the seal may move from the gap and fall off during the use of the position sensor.

[0006] An object of the present invention is to provide a rotating device and a position sensor capable of preventing the seal from falling off.

Means for Solving the Problems

[0007] To achieve the above object, the rotating device in the present invention includes: a shaft body extending in the axial direction; a case having a shaft hole and rotatably supporting the shaft body passed through the shaft hole; a seal that closes the gap between the hole peripheral wall of the shaft hole and the shaft body from one axial side; a seal retainer that fits into the gap at a position on one axial side of the seal position and prevents the seal from moving from the other axial side to one axial side; and is provided with: the hole peripheral wall has a press-fitting hole peripheral wall portion into which the seal retainer is press-fitted.

[0008] In addition, the position sensor in the present invention includes: the above rotating device; a slider attached to the shaft body; a resistance substrate having a resistor, and the slider slides on the resistor in response to the rotation of the shaft body; and is provided with: the case has a housing portion for housing the slider and the resistance substrate; the housing portion is disposed on the other axial side of the gap between the shaft body and the small-diameter hole peripheral wall portion.

Advantages of the Invention

[0009] According to the present invention, the detachment of the seal can be prevented.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4A

Figure 4B

Figure 5

Figure 6

Figure 7

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Figure 1 is a partial perspective view showing a rotating device in the embodiment of the present invention. Figure 2 is a cross-sectional view showing a position sensor in the embodiment of the present invention. In Figure 2, the left-right direction is referred to as the X direction or the radial direction, the direction away from the X axis is referred to as the outer radial direction or the “+X direction”, and the direction close to the X axis is referred to as the inner radial direction or the “-X direction”. Also, the up-down direction is referred to as the Y direction or the axial direction, the upward direction is referred to as the other side of the axial direction or the “+ direction”, and the downward direction is referred to as one side of the axial direction or the “-Y direction”.

[0012] As shown in Figure 1, the rotating device 100 includes a shaft body 1, a case 2, a seal 4, and a seal retainer 5.

[0013] As shown in Figure 2, the position sensor 200 detects the position of a device or the like, and includes the rotating device 100, a slider 6, and a resistance substrate 7. Note that the position sensor is also called a position meter.

[0014] (Shaft body 1) The shaft body 1 has a shaft diameter of a predetermined size and a shaft length of a predetermined length, and extends from one axial side (-Y direction) to the other axial side (+Y direction). The end of the shaft body 1 on the other axial side has a flange portion 1a that expands in the radially outer direction (+X direction). A slider 6 is disposed on the flange portion 1a so as to face the resistor 8.

[0015] The position sensor 200 includes, for example, a rotatable slider 6 (brush) and a resistor substrate 7 having a resistor 8 with a constant voltage applied between both ends. By sliding the slider 6 on the resistor 8, the rotational displacement of the slider 6 (shaft body 1) is output as a voltage change, and the position of a device or the like is detected based on the output voltage value.

[0016] (Case 2) The case 2 is formed into a predetermined shape by a resin material. The case 2 has a cylindrical portion 20 with a shaft hole 2a as a hollow portion, and rotatably supports the shaft body 1. The shaft hole 2a extends in the axial direction (Y direction) and is a hole through which the shaft body 1 passes. Both axial sides of the shaft hole 2a are open. The hole peripheral wall 21 of the shaft hole 2a is a peripheral wall extending from the opening edge of the axial one-side opening 21a to the opening edge of the opening on the other axial side (not shown). An annular gap 3 (see FIG. 6) is provided between the shaft body 1 passed through the shaft hole 2a and the hole peripheral wall 21. The axial one-side opening 21a has a diameter D_21a.

[0017] FIG. 3 is a cross-sectional view of the rotating device according to the embodiment of the present invention, showing a state before the seal and the seal retainer are assembled. On the hole peripheral wall 21, in order from the end on the axial one side (-Y direction) to the end on the axial other side (+Y direction), there are arranged an extending portion 22 for thermal caulking, a large-diameter hole peripheral wall portion 23, a positioning step portion 24, a medium-diameter hole peripheral wall portion 25, an inclined portion 26, a press-fitting hole peripheral wall portion 27, a seal housing step portion 28, and a small-diameter hole peripheral wall portion 29. The extending portion 22 for thermal caulking extends radially inward from the end on the axial one side of the large-diameter hole peripheral wall portion 23. The large-diameter hole peripheral wall portion 23 has a predetermined diameter D_23. The medium-diameter hole peripheral wall portion 25 has a predetermined diameter D_25. The small-diameter hole peripheral wall portion 29 has a predetermined diameter D_29.

[0018] The extension portion 22 for thermal caulking is an annular portion that tapers from a diameter D_22A, which is the same as the diameter D_23 of the large-diameter hole peripheral wall portion 23, to a diameter D_22B, which is the same as the diameter D_25 of the medium-diameter hole peripheral wall portion 25.

[0019] The diameter D_23 of the large-diameter hole peripheral wall portion 23 has a diameter smaller than the diameter D_21a of the axially one-side opening portion 21a (D_23 < D_21a). The diameter D_25 of the medium-diameter hole peripheral wall portion 25 has a diameter smaller than the diameter D_23 of the large-diameter hole peripheral wall portion 23 (D_25 < D_23). The medium-diameter hole peripheral wall portion 25 is loosely fitted with the seal retainer 5. The positioning step portion 24 is a step portion that tapers from a diameter D_24A, which is the same as the diameter D_23 of the large-diameter hole peripheral wall portion 23, to a diameter D_24B, which is the same as the diameter D_25 of the medium-diameter hole peripheral wall portion 25. The positioning step portion 24 is a step portion where the seal retainer 5 is positioned.

[0020] The inclined portion 26 is located on the other axially side (+Y direction) than the medium-diameter hole peripheral wall portion 25 and on the one axially side (-Y direction) than the press-fitting hole peripheral wall portion 27. The inclined portion 26 is an inclined surface that inclines from the end portion on the other axially side of the medium-diameter hole peripheral wall portion 25 toward the radially inner side (-X direction) from the one axially side (-Y direction) to the other axially side (+Y direction). The tip end portion of the inclined surface is continuous with the end portion on the one axially side of the press-fitting hole peripheral wall portion 27. In other words, the inclined portion 26 tapers from a diameter D_26A, which is the same as the diameter D_25 of the medium-diameter hole peripheral wall portion 25, to a diameter D_26B, which is the same as the diameter D_27 of the press-fitting hole peripheral wall portion 27, from the one axially side (-Y direction) to the other axially side (+Y direction).

[0021] The press-fitting hole peripheral wall portion 27 has a diameter D_27 that is smaller than the diameter D_25 of the medium-diameter hole peripheral wall portion 25 (D_27 < D_25). Also, the diameter D_27 of the press-fitting hole peripheral wall portion 27 has the same diameter as the diameter D_26B of the inclined portion 26 (D_27 = D_26B).

[0022] The circumferential wall portion 29 of the small-diameter hole has a diameter (D_29) that is smaller than the diameter (D_27) of the circumferential wall portion 27 of the hole to be press-fitted (D_29 < D_27). The diameter D_29 of the circumferential wall portion 29 of the small-diameter hole is larger than the diameter D_1 of the shaft body 1 (D_29 > D_1). The stepped portion 28 for seal accommodation is a stepped portion that reduces in diameter from a diameter D_28A that is the same as the diameter D_27 of the circumferential wall portion 27 of the hole to be press-fitted to a diameter D_28B that is the same as the diameter D_29 of the circumferential wall portion 29 of the small-diameter hole. Note that, among the gaps 3 between the circumferential wall 21 and the shaft body 1, the gap between the circumferential wall portion 29 of the small-diameter hole and the shaft body 1 is defined as the gap 3a.

[0023] The case 2 has a housing portion 2b (see FIG. 2) that houses the slider 6 and the resistance substrate 7. The housing portion 2b is arranged on the other side in the axial direction (+Y direction) than the gap 3a (see FIG. 2).

[0024] A seal 4 is arranged between the stepped portion 28 for seal accommodation and the end portion on the other side in the axial direction of the small-diameter portion 53 (see FIG. 7) of the seal retainer 5 described later.

[0025] (Seal 4) The seal 4 is an annular seal and has a predetermined inner diameter and a predetermined outer diameter. The cross-sectional shape along the axial direction of the seal 4 has an inverted V shape (see FIG. 6). The seal 4 is formed of a resin material having elasticity and oil resistance. The seal 4 closes the gap 3a from one side in the axial direction (-Y direction). Thereby, it becomes possible to prevent foreign matters such as dust from entering the gap 3a from one side in the axial direction (-Y direction) and passing through to the other side in the axial direction (+Y direction).

[0026] (Seal retainer 5) FIG. 4A is a plan view of the seal retainer in the embodiment of the present invention. FIG. 4B is a front view of the seal retainer in the embodiment of the present invention. FIG. 5 is a perspective view of the seal retainer in the embodiment of the present invention. As shown in FIGS. 4A, 4B, and 5, the seal retainer 5 is a frustum-shaped cylindrical body that fits into the annular gap 3 (see FIG. 3) at a position on the one side in the axial direction (-Y direction) from the position of the seal 4. The seal retainer 5, which is a cylindrical body, has a hollow portion, and the shaft body 1 (see FIG. 2) is passed through the hollow portion.

[0027] The seal retainer 5 is formed into a predetermined shape by a resin material. The seal retainer 5 has a large-diameter portion 51, a medium-diameter portion 52, a small-diameter portion 53, and a press-fitting portion 54. The large-diameter portion 51, the medium-diameter portion 52, and the small-diameter portion 53 are arranged in order from the end on one axial side toward the end on the other axial side. The large-diameter portion 51 has a diameter D_51. The medium-diameter portion 52 has a diameter D_52 which is smaller than the diameter D_51. The small-diameter portion 53 has a diameter D_53 which is smaller than the diameter D_52. That is, the respective diameters of the large-diameter portion 51, the medium-diameter portion 52, and the small-diameter portion 53 become smaller in order from the end on one axial side toward the end on the other axial side (D_51 > D_52 > D_53).

[0028] The press-fitting portion 54 has a plurality of rib portions 55 arranged at equal intervals in the circumferential direction on the outer peripheral portion of the small-diameter portion 53. In the present embodiment, four rib portions 55 are arranged at intervals of 90 degrees in the circumferential direction. The rib portion 55 extends from the position of the end on the other axial side of the medium-diameter portion 52 to the position of the center in the axial direction of the small-diameter portion 53. The rib portion 55 has a semi-circular cross-sectional shape protruding in a mountain shape radially outward (+X direction) from the outer peripheral portion of the small-diameter portion 53. Note that the envelope line in contact with the outer periphery of each of the four rib portions 55 is a circle having a diameter D_54. The diameter D_54 is larger than the diameter D_53 of the small-diameter portion 53 and smaller than the diameter D_52 of the medium-diameter portion 52 (D_52 > D_54 > D_53). The diameter of the circular envelope line maintains the diameter D_54 when the press-fitting portion 54 (rib portion 55) does not receive pressure from the inclined portion 26 or the circumferential wall portion 27 of the press-fitting hole, and contracts to the same diameter as the diameter of the inclined portion 26 or the same diameter as the diameter D_27 of the circumferential wall portion 27 of the press-fitting hole when receiving pressure. The envelope line WL is shown in FIG. 4A.

[0029] Note that the diameter D_54 of the envelope line is the diameter of the semi-circular cross-section at a portion excluding the end on the other side in the axial direction of the rib portion 55. The diameter of the semi-circular cross-section at the end on the other side in the axial direction of the rib portion 55 gradually decreases from the one side in the axial direction toward the other side in the axial direction. In other words, the diameter of the envelope line at the end on the other side in the axial direction of the press-fitting portion 54 (rib portion 55) decreases in diameter from the one side in the axial direction toward the other side in the axial direction. The diameter of the envelope line at the end on the other side in the axial direction of the rib portion 55 (rib portion 55) has the same diameter as the diameter D_53 of the small-diameter portion 53.

[0030] The diameter D_51 of the large-diameter portion 51 is substantially the same as the diameter D_23 of the large-diameter hole peripheral wall portion 23. The thickness of the large-diameter portion 51 is substantially the same as the height (axial length) from the positioning step portion 24 of the large-diameter hole peripheral wall portion 23. Thereby, the large-diameter portion 51 can be fitted into the positioning portion constituted by the large-diameter hole peripheral wall portion 23 and the positioning step portion 24. At this time, the large-diameter portion 51 is covered from the one side in the axial direction (-Y direction) by the extending portion 22 for thermal caulking. The large-diameter portion 51 is thermally caulked by the extending portion 22 for thermal caulking.

[0031] The small-diameter portion 53 extends from the middle-diameter portion 52 toward the other side in the axial direction (+Y direction). A seal 4 is disposed between the end on the other side in the axial direction of the small-diameter portion 53 and the seal housing step portion 28 (housing gap). The axial length of the small-diameter portion 53 is set such that the seal 4 is disposed in the housing gap. As described above, the gap 3a is blocked from the one side in the axial direction (-Y direction) by the seal 4. That is, the seal 4 does not drop from the other side in the axial direction (+Y direction) toward the one side in the axial direction (-Y direction) unless the seal retainer 5 moves from the other side in the axial direction (+Y direction) toward the one side in the axial direction (-Y direction). If the seal 4 does not drop off, it is possible to prevent foreign matters such as dust from entering the housing portion 2b located on the other side in the axial direction (+Y direction) through the gap 3a from the one side in the axial direction (-Y direction).

[0032] Next, the assembly procedure of the seal 4 and the seal retainer 5 will be described with reference to FIGS. 3, 6, and 7. FIG. 3 is a cross-sectional view of the rotating device according to the embodiment of the present invention, showing the state before the seal and the seal retainer are assembled. In the state shown in FIG. 3, it is assumed that the shaft body 1 and the case 2 are pre-assembled. Further, it is assumed that a slider 6 is pre-assembled on the shaft body 1 and a resistance substrate 7 is assembled on the case 2.

[0033] In the state shown in FIG. 3, first, a predetermined amount of lubricating oil is applied to the seal 4. Next, the seal 4 is inserted into the gap 3 between the shaft body 1 and the hole peripheral wall 21. Next, using a jig, the seal 4 is pushed from one axial side (-Y direction) to a predetermined position on the other axial side (+Y direction) (see FIG. 6).

[0034] Next, the seal retainer 5 is inserted into the gap 3. Next, the seal retainer 5 is pushed from one axial side (-Y direction) to the other axial side (+Y direction). As a result, the large-diameter portion 51 can be fitted into the positioning portion (a portion constituted by the large-diameter hole peripheral wall portion 23 and the positioning step portion 24). Further, the large-diameter portion 51 fitted into the positioning portion can be covered from one axial side (-Y direction) by the extending portion 22 for thermal caulking (see FIG. 7).

[0035] Next, the large-diameter portion 51 is thermally caulked to the extending portion 22 for thermal caulking. As a result, the seal retainer 5 is prevented from moving from the other axial side (+Y direction) to one axial side (-Y direction). Further, since the seal retainer 5 does not move in the one axial side (-Y direction), it is possible to prevent the seal 4 from falling off from the predetermined position.

[0036] Next, when the seal retainer 5 is pushed from one axial side (-Y direction) to the other axial side (+Y direction), the relationship between the seal retainer 5 and other components will be described. First, the relationship between the seal retainer 5 and the seal 4 will be described. For example, when the seal 4 stays at a position on one axial side rather than the predetermined position, the seal 4 is pushed into the predetermined position by the seal retainer 5 that moves from one axial side (-Y direction) to the other axial side (+Y direction).

[0037] Next, the relationship between the seal retainer 5 and the hole peripheral wall 21 will be described. When the seal retainer 5 is inserted into the shaft hole 2a, first, the end portion on the other side in the axial direction of the press-fitting portion 54 (rib portion 55) abuts against the inclined portion 26. In this case, since the diameter of the envelope line at the end portion on the other side in the axial direction of the press-fitting portion 54 (rib portion 55) decreases from the axial direction one side toward the axial direction the other side, each of the four rib portions 55 surely abuts against each position in the axial direction of the inclined portion 26. As a result, the forces received by each of the four rib portions 55 from the inclined portion 26 are balanced, and the position and inclination of the seal retainer 5 with respect to the shaft hole 2a can be easily corrected, so that it becomes easier to insert the seal retainer 5 into the shaft hole 2a.

[0038] Next, when the seal retainer 5 is further inserted into the shaft hole 2a, since the inclined portion 26 decreases in diameter from the diameter D_26A which is the same as the diameter D_25 of the middle diameter hole peripheral wall portion 25 to the diameter D_26B which is the same as the diameter D_27 of the press-fitting hole peripheral wall portion 27, as the press-fitting portion 54 (rib portion 55) moves to the other side in the axial direction with respect to the inclined portion 26, it decreases in diameter from the predetermined diameter D_54 to the same diameter as the diameter of the inclined portion 26, and eventually decreases in diameter to the same diameter as the diameter D_27 of the press-fitting hole peripheral wall portion 27. As a result, the press-fitting portion 54 (rib portion 55) can be fitted into the press-fitting hole peripheral wall portion 27. Then, the press-fitting portion 54 (rib portion 55) of the seal retainer 5 is press-fitted into the press-fitting hole peripheral wall portion 27 by the restoring force that tries to return from the diameter D_27 to the diameter D_54. In FIG. 7, the press-fitting portion 54 (rib portion 55) when it has returned to the diameter D_54 is shown by a dotted line. When the seal retainer 5 tries to move, for example, from the other side in the axial direction (+Y direction) to the one side in the axial direction (-Y direction), since it receives a large frictional force from the press-fitting hole peripheral wall portion 27, it becomes difficult to move the seal retainer 5 to the one side in the axial direction (-Y direction), so that it becomes possible to prevent the seal 4 from falling off from the predetermined position. FIG. 7 shows the seal 4 arranged at the predetermined position.

[0039] The rotating device 100 in the above embodiment includes a shaft body 1 extending in the axial direction, a case 2 having a shaft hole 2a and rotatably supporting the shaft body 1 passed through the shaft hole 2a, a seal 4 closing the gap 3 between the hole peripheral wall 21 of the shaft hole 2a and the shaft body 1 from one axial side, and a seal retainer 5 fitted into the gap 3 at a position on one axial side of the seal 4 and preventing the seal 4 from moving from the other axial side to one axial side. The hole peripheral wall 21 has a press-fitting hole peripheral wall portion 27 into which the seal retainer 5 is press-fitted.

[0040] With the above configuration, since the seal retainer 5 is press-fitted into the press-fitting hole peripheral wall portion 27, it becomes difficult for the seal retainer 5 to move from the other axial side (+Y direction) to one axial side (-Y direction). If the seal retainer 5 does not move to one axial side, it is possible to prevent the seal 4 disposed on the other axial side of the seal retainer 5 from falling off from the other axial side (+Y direction) to one axial side (-Y direction).

[0041] Further, in the rotating device 100 in the above embodiment, the seal retainer 5 has a press-fitting portion 54 press-fitted into the press-fitting hole peripheral wall portion 27, a large-diameter portion 51 disposed on one axial side of the press-fitting portion 54 and having a diameter larger than that of the press-fitting portion 54, and a small-diameter portion 53 disposed on the other axial side of the press-fitting portion 54 and having a diameter smaller than that of the press-fitting portion 54. Thereby, since the diameter of the seal retainer 5 gradually decreases from one axial side to the other axial side, the seal retainer 5 can be easily inserted into the shaft hole 2a.

[0042] Also, in the rotating device 100 in the above embodiment, the hole peripheral wall 21 includes a small-diameter hole peripheral wall portion 29 that is disposed on the other axial side of the press-fitting hole peripheral wall portion 27 and has a diameter smaller than that of the press-fitting hole peripheral wall portion, a middle-diameter hole peripheral wall portion 25 that is disposed on one axial side of the press-fitting hole peripheral wall portion 27, has a diameter larger than that of the press-fitting hole peripheral wall portion 27, and into which the seal retainer 5 is loosely fitted, and a large-diameter hole peripheral wall portion 23 that is disposed on one axial side of the middle-diameter hole peripheral wall portion 25 and has a diameter larger than that of the middle-diameter hole peripheral wall portion. As a result, the hole peripheral wall 21 forms a conical hole whose diameter gradually decreases from one axial side to the other axial side, so that the seal retainer 5 that gradually decreases in diameter from one axial side to the other axial side can be easily inserted.

[0043] Also, in the rotating device 100 in the above embodiment, the hole peripheral wall 21 has an inclined portion 26 that is disposed on the other axial side of the middle-diameter hole peripheral wall portion 25 and on one axial side of the press-fitting hole peripheral wall portion 27 and that inclines from one axial side to the other axial side toward the radially inner side in the direction of the gap side from the middle-diameter hole peripheral wall portion 25. As a result, the press-fitting portion 54 reliably abuts against the inclined portion 26 and the forces received from the inclined portion 26 are balanced, so that the position and inclination of the seal retainer 5 with respect to the shaft hole 2a can be easily corrected, and thus the seal retainer 5 can be easily inserted into the shaft hole 2a.

[0044] Also, in the rotating device 100 in the above embodiment, the hole peripheral wall 21 has an extending portion 22 for thermal caulking that extends radially inward from the end on one axial side of the large-diameter hole peripheral wall portion 23, and the large-diameter portion 51 is thermally caulked to the extending portion 22 for thermal caulking. As a result, the axial movement of the seal retainer 5 is restricted, so that it is possible to reliably prevent the seal 4 disposed on the other axial side of the seal retainer 5 from dropping off from the other axial side to the one axial side.

[0045] Also, in the rotating device 100 in the above embodiment, the hole peripheral wall 21 has a seal accommodation step portion 28 that extends radially inward from the end on the other axial side of the press-fitting hole peripheral wall portion 27, and the seal 4 is disposed in the gap between the seal accommodation step portion and the end on the other axial side of the small-diameter portion 53. Thereby, since the movement of the seal 4 from a predetermined position is restricted, the gap 3a is maintained in a state of being blocked by the seal 4, and it is possible to prevent foreign matter such as dust from entering a location disposed on the other axial side than the gap 3a.

[0046] Also, in the position sensor 200 in the above embodiment, it has the rotating device 100, a slider 6 attached to the shaft-like body, and a resistor 8, and includes a resistor substrate 7 on which the slider 6 slides in accordance with the rotation of the shaft-like body 1. The case 2 has an accommodation portion 2b that accommodates the slider 6 and the resistor substrate 7, and the accommodation portion 2b is disposed on the other axial side than the gap 3a between the shaft-like body 1 and the small-diameter hole peripheral wall portion 29. Thereby, the gap 3a is maintained in a state of being blocked by the seal 4, and it is possible to prevent foreign matter such as dust from entering the accommodation portion 2b disposed on the other axial side than the gap 3a. This becomes possible.

[0047] Furthermore, each of the above embodiments merely shows an example of concretization in implementing the present invention, and the technical scope of the present invention should not be construed in a limited manner by these. That is, the present invention can be implemented in various forms without departing from the gist or the main features thereof.

[0048] In the above embodiment, the case where the rotating device 100 is applied to the position sensor 200 is shown, but it is also possible to apply it to a rotary encoder that measures the rotational speed, the rotation angle, or the rotation position.

Industrial Applicability

[0049] The present invention is suitably used for equipment provided with a rotating device that requires prevention of seal dropout.

Explanation of Reference Numerals

[0050] 1 Shaft body 2 Case 2a Axial hole 2b Accommodation part 3 Gap 3a Gap 4 Seal 5 Seal retainer 6 Slider 7 Resistance substrate 8 Resistor 20 Cylindrical part 21 Hole peripheral wall 21a One-side opening 22 Extension part for thermal caulking 23 Large-diameter hole peripheral wall part 24 Positioning step part 25 Medium-diameter hole peripheral wall part 26 Inclined part 27 Peripheral wall part of hole to be press-fitted 28 Step part for seal accommodation 29 Small-diameter hole peripheral wall part 51 Large-diameter part 52 Medium-diameter part 53 Small-diameter part 54 Press-fitting part 55 Rib part 100 Rotation device 200 Position sensor

Claims

1. A shaft body extending in the axial direction, a case having a shaft hole and rotatably supporting the shaft body passed through the shaft hole, a seal that closes the gap between the hole peripheral wall of the shaft hole and the shaft body from one side in the axial direction, a seal retainer that fits into the gap at a position on one side in the axial direction from the position of the seal and prevents the seal from moving from the other side in the axial direction to one side in the axial direction, comprising: the hole peripheral wall has a press-fitting hole peripheral wall portion into which the seal retainer is press-fitted, a rotating device.

2. The seal retainer is a press-fitting portion that press-fits into the press-fitting hole peripheral wall portion, a large-diameter portion disposed on one side in the axial direction from the press-fitting portion and having a diameter larger than the diameter of the press-fitting portion, a small-diameter portion disposed on the other side in the axial direction from the press-fitting portion and having a diameter smaller than the diameter of the press-fitting portion, having: the rotating device according to claim 1.

3. The hole peripheral wall is a small-diameter hole peripheral wall portion disposed on the other side in the axial direction from the press-fitting hole peripheral wall portion and having a diameter smaller than the diameter of the press-fitting hole peripheral wall portion, a middle-diameter hole peripheral wall portion disposed on one side in the axial direction from the press-fitting hole peripheral wall portion, having a diameter larger than the diameter of the press-fitting hole peripheral wall portion, and into which the seal retainer loosely fits, a large-diameter hole peripheral wall portion disposed on one side in the axial direction from the middle-diameter hole peripheral wall portion and having a diameter larger than the diameter of the middle-diameter hole peripheral wall portion, having: the rotating device according to claim 2.

4. The hole peripheral wall has an inclined portion that is on the other side in the axial direction from the middle-diameter hole peripheral wall portion and on one side in the axial direction from the press-fitting hole peripheral wall portion, and that inclines from one side in the axial direction to the other side in the axial direction toward the radially inner side in the direction from the middle-diameter hole peripheral wall portion to the gap side, the rotating device according to claim 3.

5. The hole peripheral wall has a thermo-crimping extending portion that extends radially inward in the direction of the gap from the end on one side in the axial direction of the large-diameter hole peripheral wall portion, the large-diameter portion is thermo-crimped to the thermo-crimping extending portion, the rotating device according to claim 3.

6. The hole peripheral wall has a seal accommodating step portion that extends radially inward from the end on the other side in the axial direction of the press-fitting hole peripheral wall portion, the seal is disposed in the gap between the seal accommodating step portion and the end on the other side in the axial direction of the small-diameter portion, the rotating device according to claim 4.

7. The rotating device according to any one of claims 3 to 5, a slider attached to the shaft body, a resistance substrate having a resistor, and the slider slides on the resistor in accordance with the rotation of the shaft body, comprising: The case has a housing portion that houses the slider and the resistive substrate, The housing portion is disposed on the other axial side than the gap between the shaft-like body and the inner peripheral wall portion of the small-diameter hole, Position sensor.

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