Rotation sensor and switch device equipped with rotation sensor

Abstract

To suitably detect a rotation operation of an operation dial.SOLUTION: A switch device 1 includes an operation dial 9 that can be rotated about a rotation axis X, and a rotation sensor 10. The rotation sensor 10 includes an optical sensor 7 and a light-blocking plate 86. The optical sensor 7 includes a light-emitting unit 71, and a pair of light-receiving units 72a and 72b disposed to face each other with a space from the light-emitting unit 71. The light-blocking unit 86 moves in a circumferential direction about the rotation axis X between the light-emitting unit 71 and the pair of light-receiving units 72a and 72b in conjunction with the rotation operation of the operation dial 9. The pair of light-receiving units 72a and 72b are arranged in the circumferential direction about the rotation axis X. The light-blocking plate 86 has a thickness in a radial direction of the rotation axis X and has a predetermined length in the circumferential direction about the rotation axis X. The light-blocking plate 86 is formed in a tapered shape in a manner that one end side and the other end side in the circumferential direction about the rotation axis X become thinner in the radial direction of the rotation axis X.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a rotation sensor and a switch device including a rotation sensor. [Background technology]

[0002] Patent Document 1 discloses a switch device configured to detect the rotation of an operation dial using an optical sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-91613 A Summary of the Invention [Problem to be solved by the invention]

[0004] The switch device has a light-shielding blade that moves in conjunction with the rotation of the operation dial, and an optical sensor. The optical sensor has a light-emitting portion and a pair of light-receiving portions that are disposed opposite each other with a gap therebetween. In the switch device, when the operation dial is operated, the light-shielding blade moves across between the light-emitting portion and the pair of light-receiving portions from one side to the other, depending on the operation direction of the operation dial. The switch device outputs a signal that can specify the order in which the light reception in the pair of light receiving sections is interrupted and the number of times that the light reception is interrupted.

[0005] In the device that is the control target of the operation dial, the operation direction and operation amount of the operation dial are identified based on the signal output by the switch device, and the operation of the controlled device is controlled based on the identified operation direction and operation amount. For this reason, it is necessary to be able to properly detect the rotation operation of the operation dial (rotating body). [Means for solving the problem]

[0006] The present invention relates to an optical sensor including a light emitting unit and a pair of light receiving units disposed opposite the light emitting unit with a gap therebetween; a light-shielding plate that moves in a circumferential direction around a rotation axis between the light-emitting unit and the pair of light-receiving units in conjunction with the rotation of a rotating body, The pair of light receiving portions are arranged in a circumferential direction around the rotation axis, the light blocking plate has a thickness in a radial direction of the rotation shaft and a predetermined length in a circumferential direction around the rotation shaft, The light blocking plate is formed in a tapered shape at one end side and the other end side in a circumferential direction around the rotating shaft such that the thickness in a radial direction of the rotating shaft becomes thinner. Effect of the Invention

[0007] According to the present invention, the rotation operation of the rotating body can be appropriately detected. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a diagram illustrating a switch device. [Diagram 2] FIG. [Diagram 3] FIG. 2 is a diagram illustrating a rotating body. [Figure 4] FIG. [Diagram 5] FIG. 2 is a diagram illustrating an optical sensor. [Figure 6] 4A and 4B are diagrams illustrating the cross-sectional shape of a light-shielding plate. [Figure 7] 10A to 10C are diagrams illustrating the function of a light blocking plate according to an embodiment. [Figure 8] 11A and 11B are diagrams illustrating the cross-sectional shape of a light blocking plate according to a comparative example. [Figure 9] 11A and 11B are diagrams illustrating the function of a light blocking plate according to a comparative example. [Figure 10] 13A and 13B are diagrams illustrating a light blocking plate according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described. Fig. 1(A) is a front view of the switch device 1. Fig. 1(B) is an exploded perspective view of the switch device 1. Fig. 2 is a schematic cross-sectional view of the switch device 1 taken along line AA in Fig. 1(A).

[0010] As shown in FIG. 2, the main body case 2 (case) of the switch device 1 has a body 3, a front cover 4, and a rear cover 5. The main body case 2 is formed by assembling a body 3, a front cover 4, and a rear cover 5 in the direction of a rotation axis X of an operation dial 9, which will be described later.

[0011] The switch device 1 includes a rotation sensor 10 for detecting the rotation of the operation dial 9. The rotation sensor 10 includes a light shielding plate 86 that rotates around a rotation axis X in conjunction with the rotation of the operation dial 9, and an optical sensor 7.

[0012] The substrate 6 on which the optical sensor 7 is mounted is disposed within the body 3 of the switch device 1 . The body 3 has a peripheral wall portion 31 and a partition wall 32. The peripheral wall portion 31 is formed to have a size capable of accommodating the rear cover 5 and the board 6. The partition wall 32 partitions the inside of the peripheral wall portion 31 into a space S1 on the front cover 4 side and a space S2 on the rear cover 5 side.

[0013] The rear cover 5 has a bottom wall portion 51 and a peripheral wall portion 52. The bottom wall portion 51 is formed to a size sufficient to substantially cover the opening of the peripheral wall portion 31 of the body 3. The peripheral wall portion 52 surrounds the entire outer periphery of the bottom wall portion 51 and is inserted inside the peripheral wall portion 31 of the body 3. A tip 52a of the peripheral wall portion 52 abuts against the substrate 6 from the direction of the rotation axis X. In this state, the rear cover 5 is fixed to the body 3 with screws (not shown). The substrate 6 and the rear cover 5 are accommodated in a space S2 within the body 3.

[0014] A front cover 4 is fitted to the front of the body 3. 1, the front cover 4 is provided with a support portion 45 for the push buttons 41, 42. The support portion 45 protrudes from the body 3. The push buttons 41, 42 are aligned vertically on the body 3 and are provided so as to be operable by being pressed. A dial support part 451 having a substantially circular outer shape is located to the side of the push buttons 41 and 42. As shown in Fig. 2, a through hole 450 surrounded by a cylindrical wall 452 opens in the center of the dial support part 451. The support cylinder 33 extending from the body 3 is located in the center of the through hole 450. The cylindrical wall 452 and the support cylinder 33 are arranged concentrically about the rotation axis X. In the radial gap between the cylindrical wall 452 and the support cylinder 33, the first cylindrical portion 81 of the rotor 8 is located.

[0015] Fig. 3(A) is a plan view of the rotor 8 as viewed from the direction of the rotation axis X. Fig. 3(B) is a perspective view showing a cross section of the rotor 8 taken along the line AA in Fig. 3(A). 3A corresponds to a view of the rotor 8 seen from the substrate 6 side.

[0016] The rotor 8 has a first cylindrical portion 81 that is fitted onto the support cylinder 33 , and a second cylindrical portion 82 that has a larger diameter than the first cylindrical portion 81 . The first cylindrical portion 81 and the second cylindrical portion 82 are connected to each other via a connection portion 83 provided on the outer periphery of the base end side of the first cylindrical portion 81 . The connection portion 83 is provided around the entire outer periphery of the first cylindrical portion 81. The connection portion 83 is provided in a direction perpendicular to the first cylindrical portion 81. The connection portion 83 is connected to the inner periphery of the second cylindrical portion 82. A detent groove 831 is provided on the inner surface of the connection portion 83. The detent groove 831 is provided around the entire circumferential direction around the rotation axis X.

[0017] A flange portion 84 is provided on the end of the second cylindrical portion 82 opposite to the connection portion 83. The flange portion 84 is provided in a direction perpendicular to the second cylindrical portion 82. The flange portion 84 is provided around the entire outer periphery of the second cylindrical portion 82. A cylindrical support portion 85 is provided on the surface of the flange portion 84 opposite to the second cylindrical portion 82. 3A, the support portion 85 is in the shape of a ring surrounding the rotation axis X at a predetermined interval. An outer periphery 851 of the support portion 85 is in the shape of a circular arc along a virtual circle Im0 centered on the rotation axis X. A light shielding plate 86 is provided at the end of the support portion 85 on the front side of the page. The light blocking plate 86 is a plate-shaped portion having a predetermined length in the circumferential direction about the rotation axis X. The light blocking plates 86 are provided over the entire circumference in the circumferential direction about the rotation axis X at predetermined intervals.

[0018] When viewed from the direction of the rotation axis X, the light blocking plate 86 has an arc shape along the circumferential direction around the rotation axis X. An outer periphery 861 of the light blocking plate 86 is formed in a shape that follows the imaginary circle Im1. The imaginary circle Im1 has a smaller diameter than the imaginary circle Im0. Therefore, the outer periphery 861 of the light blocking plate 86 is located slightly on the inner diameter side of the outer periphery 851 of the support portion 85.

[0019] An inner circumference 862 of the light blocking plate 86 is formed in a shape that follows an imaginary circle Im2. The imaginary circle Im2 is formed with a diameter smaller than that of the imaginary circle Im1 and larger than that of an imaginary circle Im3 that follows the inner circumference of the support portion 85. The light blocking plate 86 has a thickness W86 that serves as a reference in the radial direction. The thickness W86 can be expressed by the following formula (1) using the radius r1 of the imaginary circle Im1 and the radius r2 of the imaginary circle Im2: W86=r1-r2 (1)

[0020] The length L862 of the inner circumference 862 in the circumferential direction around the rotation axis X is smaller than the length L861 of the outer circumference (L862 <L861)。 Therefore, the length of the light blocking plate 86 in the circumferential direction around the rotation axis X becomes wider toward the outer diameter side.

[0021] The light shielding plate 86 is formed in a tapered shape such that one end side and the other end side in the circumferential direction about the rotation axis X become thinner in the radial direction of the rotation axis X. The apex P1 on one end side of the light shielding plate 86 and the apex P2 on the other end side are located on the imaginary circle Im1 described above.

[0022] 2, the rotating body 8 is provided in the body 3 with the first cylindrical portion 81 fitted onto the support cylinder 33. In this state, the rotating body 8 is rotatably supported by the support cylinder 33. An operation dial 9 is fitted onto and fixed to the tip 81a side of the first cylindrical portion 81. As shown in Fig. 1, a protrusion 811 and a locking claw 812 are provided on the outer periphery of the first cylindrical portion 81. The operation dial 9 is provided with a cylindrical fitting portion 91 adjacent to the grip portion 90. The fitting portion 91 is provided with a key groove 911 and an engagement piece 912. When the fitting portion 91 of the operation dial 9 is inserted into the first cylindrical portion 81 of the rotating body 8, the key groove 911 and the engagement piece 912 of the fitting portion 91 respectively engage with the protrusion 811 and the locking claw 812 on the rotating body 8 side. As a result, the operation dial 9 and the rotating body 8 are connected to be able to rotate together. In this state, the operation dial 9 is disposed so as to cover the through-hole 450 of the front cover 4 when viewed from the direction of the rotation axis X. Furthermore, the operation dial 9 is rotatably supported by the support cylinder 33 on the body 3 side via the rotating body 8.

[0023] 2, the support cylinder 33 is formed integrally with the body 3. The support cylinder 33 is a cylindrical member surrounding the rotation axis X at a predetermined interval. The inner region (rotation axis X side) of the support cylinder 33 is an opening 30 penetrating the partition wall 32 in the thickness direction. In the opening 30 when viewed from the front cover 4 side, the substrate 6 is exposed.

[0024] The support cylinder 33 extends in a direction away from the substrate 6 along the rotation axis X. A tip 33a of the support cylinder 33 is located outside the body 3 and inside the front cover 4 described above.

[0025] FIG. 4 is a cross-sectional view of the switch device 1 taken along the line AA in FIG. 4, cross-hatched areas are shown penetrating through the thickness direction of the partition wall 32. The cross-hatched areas are opening areas in the partition wall 32, and the substrate 6 (not shown) is exposed on the inner side of the opening area.

[0026] 4, an inner guide wall 34 and an outer guide wall 35 are located on the outer diameter side of the support cylinder 33. When viewed from the direction of the rotation axis X, the inner guide wall 34 and the outer guide wall 35 form a substantially annular shape. The inner guide wall 34 is formed with an inner diameter r34 that is larger than an outer diameter R33 of the support cylinder 33. The inner guide wall 34 is formed with an outer diameter R34 that is smaller than an inner diameter r35 of the outer guide wall 35.

[0027] The inner guide wall 34 and the outer guide wall 35 each extend toward the front side of the paper. A light shielding plate 86 of the rotating body 8 connected to the operation dial 9 is disposed between the inner guide wall 34 and the outer guide wall 35. The inner guide wall 34 and the outer guide wall 35 suppress vibration of the light shielding plate 86 when the light shielding plate 86 moves around the rotation axis X in conjunction with the operation of the operation dial 9. The inner guide wall 34 and the outer guide wall 35 function as guide rails for suppressing vibration of the light shielding plate 86.

[0028] A support hole 342 for the moderation pin 15 (see FIG. 2) is provided in the partition wall 32 of the body 3. The support hole 342 is provided by utilizing a rib 343 that connects the inner guide wall 34 and the support cylinder 33.

[0029] 2, the support hole 342 is a bottomed hole with an opening facing the operation dial 9 side (the left side in FIG. 2). The support hole 342 faces the area where the detent groove 831 of the rotating body 8 is provided. A spring Sp and a detent pin 15 are housed in the support hole 342. The detent pin 15 can freely move in and out of the support hole 342 in the direction of the rotation axis X. The detent pin 15 is elastically engaged with a detent groove 831 of the rotating body 8 by the biasing force applied by the spring Sp.

[0030] In this embodiment, the operation dial 9 connected to the rotating body 8 is positioned by the biasing force acting on the rotating body 8 from the moderation pin 15. Specifically, when no operating force is acting on the operation dial 9 by the user, the light shielding plate 86 is arranged at a position that does not impede light reception at the light receiving section 72 (72a, 72b) of the optical sensor 7 described below (see FIG. 5A) or at a position that prevents light reception.

[0031] 4, the outer guide wall 35 is provided with recesses 352 that bulge outwardly. A plurality of recesses 352 are provided at intervals in the circumferential direction around the rotation axis X. In this embodiment, one recess 352 is positioned on a straight line L connecting the support hole 342 and the rotation axis X as viewed from the direction of the rotation axis X.

[0032] Furthermore, when viewed from the direction of the rotation axis X, two recesses 352, 352 are provided on each of one side and the other side of the straight line L. The recesses 352, 352 on one side of the straight line L and the recesses 352, 352 on the other side are provided in a positional relationship that is approximately symmetrical with respect to the straight line L.

[0033] These recesses 352 are provided to avoid interference with the engagement piece 36 extending from the partition wall 32. As shown in Fig. 2, the engagement piece 36 extends in a direction away from the substrate 6 along the rotation axis X. The base end side of the engagement piece 36 is supported in a cantilever manner, and the tip side where the claw portion 36a is provided is elastically displaceable in the radial direction of the rotation axis X.

[0034] The engagement piece 36 is engaged with the flange portion 84 of the rotating body 8 in the direction of the rotation axis X. In this state, the rotating body 8 inserted into the support cylinder 33 is permitted to rotate about the rotation axis X, but movement in a direction away from the substrate 6 is restricted.

[0035] 4, the inner guide wall 34 is provided with a recess 341 for avoiding interference with the optical sensor 7. The recess 341 is formed by recessing the inner guide wall 34 toward the rotation axis X side. The outer guide wall 35 is also provided with a recess 351 for avoiding interference with the optical sensor 7. The recess 351 is formed by recessing the outer guide wall 35 radially outwardly of the rotation axis X.

[0036] In the partition wall 32, a through hole 321 is provided in an area surrounded by the recesses 341 and 351. The through hole 321 is provided at a position shifted by 180 degrees in the circumferential direction around the rotation axis X from the support hole 342. When viewed from the rotation axis X direction, the through hole 321 and the support hole 342 are located on the straight line L. When viewed from the rotation axis X direction, the through hole 321 has a substantially rectangular shape. The through hole 321 is formed to have a size that allows an optical sensor 7, which will be described later, to pass through, and the optical sensor 7 is located in the center of the through hole 321.

[0037] Fig. 5 is a diagram for explaining the optical sensor 7. Fig. 5(A) is a plan view of the optical sensor 7 as viewed from the direction of the rotation axis X. Fig. 5(B) is a diagram showing a cross section of the optical sensor 7 taken along line XX in Fig. 5(A) together with the substrate 6. In FIG. 5, in order to clarify the positional relationship between the light sensor 7 and the light shielding plate 86, the light shielding plate 86 is shown in cross section or by virtual lines. Furthermore, the light emitting section 71 and the light receiving section 72 (72a, 72b) are shown in schematic form to explain the arrangement of the light emitting section 71 and the light receiving section 72 (72a, 72b) of the optical sensor 7. In the following explanation, when there is no need to distinguish between the light receiving sections 72a and 72b, they may simply be referred to as the light receiving section 72.

[0038] 5, the optical sensor 7 has a light-emitting unit 71 and a pair of light-receiving units 72 (72a, 72b). The light-emitting unit 71 and the light-receiving units 72 (72a, 72b) are disposed opposite each other with a gap W7 between them. The area between the light-emitting unit 71 and the light-receiving units 72 (72a, 72b) is the area in which the light-shielding plate 86 of the rotating body 8 moves. The optical sensor 7 is provided on the substrate 6 in an orientation such that the light emitting portion 71 is positioned on the inner diameter side of the movement locus of the light blocking plate 86 and the light receiving portion 72 (72a, 72b) is positioned on the outer diameter side of the light blocking plate 86.

[0039] In the orthogonal direction of the substrate 6, the light emitting portion 71 and the light receiving portion 72 (72a, 72b) are disposed at positions spaced apart from the surface 6a of the substrate 6 by the same height h. The light-emitting unit 71 emits infrared light toward the light-receiving unit 72. The pair of light-receiving units 72 (72a, 72b) are provided with a gap W72 between them. The light-emitting unit 71 is located on a straight line C that connects the rotation axis X and the midpoint between the light-receiving units 72a, 72b. Therefore, the distance La between the center of the light-emitting surface of the light-emitting unit 71 and the center of the light-receiving surface of the light-receiving unit 71a is equal to the distance Lb between the center of the light-emitting surface of the light-emitting unit 71 and the center of the light-receiving surface of the light-receiving unit 71b.

[0040] In the optical sensor 7, the infrared light emitted from the light-emitting unit 71 is received by the light-receiving units 72a and 72b. The light-receiving units 72a and 72b output a high signal while receiving the infrared light emitted from the light-emitting unit 71. The light-receiving units 72a and 72b output a low signal when the reception of the infrared light is blocked by a light-shielding plate 86 passing between the light-emitting unit 71 and the light-receiving units 72a and 72b.

[0041] As described above, the operation dial 9 is positioned by the biasing force acting from the moderation pin 15. In this state, the light shielding plate 86 is disposed at a position that does not interfere with the reception of infrared light by, for example, the pair of light receiving portions 72 (72a, 72b) (see FIG. 5A).

[0042] When the operation dial 9 is operated, the light blocking plate 86 moves along a movement locus in one direction determined according to the operation direction of the operation dial 9. In this case, the light shielding plate 86 blocks light from being received by the light receiving sections 72a and 72b.

[0043] Fig. 6(A) is a diagram for explaining the relationship between the trajectory of infrared light irradiated from the light-emitting unit 71 and the shape of the light-shielding plate 86. Fig. 6(B) is a diagram for explaining the positional relationship between a vertex P1 of the light-shielding plate 86 and one side 863. Fig. 6(C) is a diagram for explaining the positional relationship between a vertex P2 of the light-shielding plate 86 and the other side 864. Fig. 7A is a diagram for explaining a change in the infrared light receiving state at the light receiving units 72a and 72b in accordance with the displacement of the light shielding plate 86. Fig. 7B is a diagram for explaining a transition of the output signal of the light receiving unit 72 (72a, 72b) when the light shielding plate 86 is displaced in the direction shown in Fig. 7A.

[0044] For example, when the light-shielding plate 86 rotates in the clockwise direction in FIG. 7A, reception of infrared light is blocked in the order of the light-receiving portion 72a and the light-receiving portion 72b, and then reception of infrared light is resumed in the order of the light-receiving portion 72a and the light-receiving portion 72b. In this case, the waveform of the output signal from the optical sensor 7 becomes the waveform shown in FIG.

[0045] Specifically, at time t1, apex P1 on one end side of the light-shielding plate 86 reaches a position that blocks light reception at the light-receiving unit 72a. As a result, after time t1, the output signal of the light-receiving unit 72a drops from High to Low. Then, at time t2, the light-shielding plate 86 blocks light reception at the light-receiving unit 72a, so the output signal of the light-receiving unit 72a goes Low. After that, at time t3, apex P1 on one end side of the light-shielding plate 86 reaches a position where it blocks light reception at the light-receiving unit 72b. As a result, after time t3, the output signal of the light-receiving unit 72b drops from High to Low. Then, at time t4, the light-shielding plate 86 blocks light reception at the light-receiving unit 72b, so the output signal of the light-receiving unit 72b goes Low.

[0046] Then, at time t6, apex P2 on the other end side of the light-shielding plate 86 reaches a position where blocking of light reception at the light-receiving unit 72a ends. As a result, after time t6, the output signal of the light-receiving unit 72a rises from Low to High. Then, at time t7, the light-shielding plate 86 does not block light reception at the light-receiving unit 72a, so the output signal of the light-receiving unit 72a becomes High. Then, at time t8, apex P2 on the other end side of the light shielding plate 86 reaches a position where blocking of light reception at the light receiving unit 72b ends. As a result, after time t8, the output signal of the light receiving unit 72b rises from Low to High. Then, at time t9, the light shielding plate 86 does not block light reception at the light receiving unit 72b, so the output signal of the light receiving unit 72b becomes High. Between time t4 and time t6, both the reception of infrared light by the light receiving unit 72a and the reception of infrared light by the light receiving unit 72b are blocked by the light blocking plate 86. Therefore, at time t5 between time t4 and time t6, both the output signal of the light receiving unit 72a and the output signal of the light receiving unit 72b become Low.

[0047] In this way, when the light-shielding plate 86 moves in the clockwise direction in FIG. 7A, the output signal of the light-receiving portion 72a starts to decrease / increase before the output signal of the light-receiving portion 72b starts to decrease / increase. Incidentally, when the light-shielding plate 86 moves counterclockwise in FIG. 7A, the output signal of the light-receiving portion 72b starts to decrease / increase before the output signal of the light-receiving portion 72a starts to decrease / increase.

[0048] As a result, in a control device (not shown) to which the output signal of the optical sensor 7 is input, the operation direction of the operating dial 9 can be determined based on whether the change in the output signal of the light receiving part 72a or the change in the output signal of the light receiving part 72b occurs first.

[0049] Furthermore, the control device identifies the amount of operation of the operation dial from the number of times the output signal of the optical sensor 7 (light receiving sections 72a, 72b) drops.

[0050] As an example, a state in which the output signals of the light receiving sections 72a, 72b are both High is defined as a first state, and a state in which the output signals of the light receiving sections 72a, 72b are both Low is defined as a second state. Then, the point in time when the output signal from the light receiving units 72a, 72b goes from the first state or the second state through a transition state in which one of the output signals goes high and the other goes low, and the state changes to the second state or the first state, is defined as "1 count." Thereafter, the count is incremented each time the state becomes state 1 or state 2. The operation amount of the operation dial 9 is determined from the total count number from when the state of the output signal starts to change to when the state change stops.

[0051] In this embodiment, the light-shielding plate 86 has a vertex P1 on one end side and a vertex P2 on the other end side in the circumferential direction around the rotation axis X that determine the timing at which the light-receiving portion 72 (72a, 72b) blocks and unblocks the infrared light. In order to ensure that the position (blocking point) at which the light-shielding plate 86 blocks infrared light reception at the light-receiving section 72 (72a, 72b) and the position (opening point) at which the light-receiving section 72 no longer blocks the light are aligned in the radial direction of the rotation axis X, the shape of the light-shielding plate 86 is set to satisfy the following conditions.

[0052] (I) One end side and the other end side in the circumferential direction around the rotation axis X are formed in a tapered shape in which the thickness in the radial direction of the rotation axis X becomes thinner (see FIG. 6(A)). (II) The vertex P1 on one end side of the light blocking plate 86 and the vertex P2 on the other end side are located on the above-mentioned common imaginary circle Im1 (see FIG. 6A). (III) One side 863 of the light-shielding plate 86 in the circumferential direction around the rotation axis X is shaped so that when the apex P1 is positioned on the straight line Ln2 connecting the light-emitting portion 71 and the light-receiving portion 72b, the inner diameter side of the apex P1 does not cross the straight line Ln2 (see (B) of Figure 6). (IV) The other side 864 of the light-shielding plate 86 in the circumferential direction around the rotation axis X is shaped so that when the apex P2 is located on the straight line Ln1 connecting the light-emitting portion 71 and the light-receiving portion 72a, the inner diameter side of the apex P2 does not cross the straight line Ln1 (see (C) of Figure 6).

[0053] Thus, in the light shielding plate 86 according to the embodiment, the position (light shielding point) that blocks light reception at the light receiving section 72 (72a, 72b) and the position (aperture point) that eliminates the blocking of light reception are located on a common imaginary circle Im1. This allows the waveforms of the output signals from the light receiving sections 72 (72a, 72b) to converge to the same waveform.

[0054] FIG. 8 is a diagram illustrating a light blocking plate 86A according to a comparative example. Fig. 8A is a diagram for explaining the relationship between the trajectory of infrared light emitted from the light-emitting unit 71 and the shape of a light-shielding plate 86A according to a comparative example. Fig. 8B is a diagram for explaining the positional relationship between vertices P1 and P3 of the light-shielding plate 86A and one side 863. Fig. 8C is a diagram for explaining the positional relationship between vertices P2 and P4 of the light-shielding plate 86A and the other side 864. Fig. 9A is a diagram for explaining the change in the infrared light receiving state at the light receiving units 72a and 72b in accordance with the displacement of the light shielding plate 86A. Fig. 9B is a diagram for explaining the transition of the output signal of the light receiving unit 72 (72a and 72b) when the light shielding plate 86A is displaced in the direction shown in Fig. 9A.

[0055] The light shielding plate 86A differs from the light shielding plate 86 described above in the arrangement of one side 863 and the other side 864 in the circumferential direction around the rotation axis X. One side 863 and the other side 864 are formed in a shape along a straight line along a diameter line Lc passing through the center of the imaginary circle Im1. Therefore, the width of the light shielding plate 86A on the inner diameter side is wider than that of the light shielding plate 86 described above by an amount shown by crossed hatching in the figure.

[0056] Therefore, one side 863 of the light-shielding plate 86A in the circumferential direction around the rotation axis X is shaped so that when the vertex P1 is located on the straight line Ln2 connecting the light-emitting portion 71 and the light-receiving portion 72b, the inner diameter side of the vertex P1 crosses the straight line Ln2 (see (B) of Figure 8). Furthermore, the other side 864 of the light-shielding plate 86A in the circumferential direction around the rotation axis X is shaped so that when the apex P2 is located on the straight line Ln1 connecting the light-emitting portion 71 and the light-receiving portion 72a, the inner diameter side of the apex P2 crosses the straight line Ln1 (see (C) of Figure 8).

[0057] For example, when the light blocking plate 86A rotates in the clockwise direction in FIG. 9(A), the waveform of the output signal of the optical sensor 7 becomes the waveform shown in FIG. 9(B).

[0058] Specifically, at time t1, apex P1 on one end side of light-shielding plate 86A reaches a position that blocks light reception at light-receiving unit 72a. As a result, after time t1, the output signal of light-receiving unit 72a drops from High to Low. Then, at time t2, the output signal of light-receiving unit 72a becomes Low because light-shielding plate 86A blocks light reception at light-receiving unit 72a. Then, at time t3', apex P3 on one end side of light-shielding plate 86A reaches a position where it blocks light reception at light-receiving unit 72b. As a result, after time t3', the output signal of light-receiving unit 72b drops from High to Low. Then, at time t4', the output signal of light-receiving unit 72b becomes Low because light-shielding plate 86A blocks light reception at light-receiving unit 72b.

[0059] As described above, in the light blocking plate 86A, when the apex P1 reaches the straight line Ln2, the apex P3 exceeds the straight line Ln2 (see FIG. 8B). Therefore, the vertex P3 reaches the straight line Ln2 at an earlier time (time t3') than the time when the vertex P1 reaches the straight line Ln2 (time t3 in FIG. 9B).

[0060] Therefore, after time t3', the output signal of the light receiving element 72b will decrease. However, since vertex P3 is farther away from the light receiving element 72b than vertex P1, the rate at which the output signal of the light receiving element 72b decreases will be slower than when the infrared light is blocked by vertex P1. 9B, in the case of the light shielding plate 86A, the output signal from the light receiving unit 72b starts to decrease at time t3', which is earlier than time t3 in the case of the light shielding plate 86, and the output signal goes Low at time t4'. Here, time t4' at which the output signal goes Low in the light shielding plate 86A is earlier than time t4 in the case of the light shielding plate 86.

[0061] Then, at time t6', apex P4 on the other end side of the light-shielding plate 86A reaches a position where blocking of light reception at the light-receiving unit 72a ends. As a result, after time t6', the output signal of the light-receiving unit 72a rises from Low to High. Then, at time t7', the light-shielding plate 86A does not block light reception at the light-receiving unit 72a, so the output signal of the light-receiving unit 72a becomes High. Then, at time t8, apex P2 on the other end side of the light-shielding plate 86A reaches a position where blocking of light reception at the light-receiving unit 72b ends. As a result, after time t8, the output signal of the light-receiving unit 72b rises from Low to High. Then, at time t9, the light-shielding plate 86A does not block light reception at the light-receiving unit 72b, so the output signal of the light-receiving unit 72b becomes High.

[0062] As described above, in the light blocking plate 86A, when the vertex P2 reaches the straight line Ln1, the vertex P4 exceeds the straight line Ln1 (see FIG. 8C). Therefore, the vertex P4 reaches the straight line Ln1 at a time (time t6') later than the time (time t6) when the vertex P2 reaches the straight line Ln1.

[0063] Therefore, after time t6', the output signal of the light receiving element 72a will rise, but since vertex P4 is farther from the light receiving element 72b than vertex P2, the rate at which the output signal of the light receiving element 72b rises will be slower than when the infrared light is blocked by vertex P2. As shown in (B) of Figure 9, in the case of the light shielding plate 86A, the rise in the output signal of the light receiving section 72a begins at time t6', which is later than time t6 in the case of the light shielding plate 86, and the time t7' at which the output signal reaches High is later than time t7 in the case of the light shielding plate 86.

[0064] In this way, in the case of the light shielding plate 86A according to the comparative example, the portion involved in blocking and canceling the blocking of the infrared light has a radial thickness, and therefore the position where the light shielding plate 86A blocks the reception of the infrared light at the light receiving units 72a and 72b (light blocking point) and the position where the light receiving unit 72a and 72b cancels the blocking of the light (opening point) change in the radial direction of the rotation axis X. As a result, there is a discrepancy between the timing at which the light receiving sections 72a and 72b block the infrared light due to the light blocking plate 86A and the timing at which the light blocking is released. Therefore, in order to properly detect the rotation of the operation dial 9, it is necessary to: (a) lengthen the sampling period of the output signals of the light receiving parts 72a and 72b; and (b) shorten the sampling cycle of the light receiving parts 72a and 72b. However, in the case of (a), it takes time to identify the operation direction and operation amount of the operation dial 9. In the case of (b), the processing load on the control device to which the output signal is input increases.

[0065] In contrast, in the case of the light shielding plate 86 according to the embodiment, the degree to which the timing at which the light is blocked by the light shielding plate 86 and the blocking is released fluctuates due to the influence of the radial thickness of the light shielding plate 86 can be suppressed. This makes it possible to suppress the difference between the change in the output signal of the light receiving portion 72a and the change in the output signal of the light receiving portion 72b, so that the rotation of the rotating body can be appropriately detected from the output signals of the two light receiving portions 72a, 72b.

[0066] Here, in the case of the rotation sensor 10 of the embodiment, the larger the phase difference between the waveform of the output signal of the light receiving portion 72a and the waveform of the output signal of the light receiving portion 72b, the more advantageous it is for detection when the operating dial 9 is operated at high speed. For example, in the case of the light-shielding plate 86, as shown in FIG. 7B, the time difference Δt (t3-t2) from time t2 when the output signal of the light-receiving section 72a drops to Low to time t3 when the output signal of the light-receiving section 72b starts to drop corresponds to the phase difference of the waveforms referred to here.

[0067] In the case of the light-shielding plate 86A according to the comparative example, as shown in (B) of Figure 9, the time difference Δt' from time t2 when the output signal of the light-receiving section 72a drops to Low to time t3' when the output signal of the light-receiving section 72b begins to drop corresponds to the phase difference of the waveform. As described above, in the case of the light shielding plate 86A, the decrease in the output signal of the light receiving section 72b begins at time t3', which is earlier than in the case of the light shielding plate 86. Therefore, the time difference Δt' in the case of the light shielding plate 86A is shorter than the time difference Δt in the case of the light shielding plate 86.

[0068] Here, the faster the operation speed of the operation dial 9, the smaller the phase difference between the waveform of the output signal of the light receiving unit 72a and the waveform of the output signal of the light receiving unit 72b becomes. That is, the time difference Δt' in the case of the light shielding plate 86A and the time difference Δt in the case of the light shielding plate 86 become smaller. 7B and 9B, the light shielding plate 86 has a larger time difference (phase difference) between the waveforms of the output signals of the light receiving units 72a and 72b than the light shielding plate 86A. Therefore, when the operation dial 9 is operated at high speed and the period in which the light shielding plate crosses the optical sensor 10 becomes shorter, the light shielding plate 86 has a larger margin of time until the time difference Δt becomes zero (=0) than the light shielding plate 86A. Therefore, the switch device 1 employing the light-shielding plate 86 according to the embodiment has more leeway for an increase in the operation speed of the operating dial 9, and can more appropriately detect high-speed operation of the operating dial 9 than the switch device employing the light-shielding plate 86A according to the comparative example.

[0069] In this way, the change in the output signal of the light receiving element 72a and the change in the output signal of the light receiving element 72b are aligned, so that the waveforms of the output signals of the light receiving elements 72a and 72b converge to the same waveform. This improves the accuracy of detecting the rotation operation of the operation dial 9, and shortens the time required for detection. Furthermore, even if the user rotates the operation dial 9 quickly, the operation of the operation dial can be detected and the amount of operation of the operation dial can be counted more appropriately. Therefore, the rotation operation of the operation dial 9 can be detected appropriately. Furthermore, there is no need to shorten the read cycle (sampling cycle) of the output signal on the control device side to which the output signal is input in preparation for a case where the rotation operation of the operation dial 9 is fast. In other words, it is possible to suitably prevent an increase in the processing load on the control device side when detecting the rotation operation of the operation dial 9.

[0070] In this way, the light blocking plate 86 according to the embodiment is effective for detecting the rotation (operation detection) of a rotating body in an optical sensor having two or more light receiving parts. The waveform of the output signal (output voltage) of the light receiving unit 72 (72a, 72b) can be controlled by positioning the apex P1 on one end side and the apex P2 on the other end side of the light shielding plate 86 on any imaginary circle Im1 centered on the rotation axis X. This makes it possible to create an output signal waveform that can detect high-speed operation of the operation dial 9 and an output signal waveform that is less susceptible to the effects of noise, which is expected to reduce erroneous detection on the control device side. In addition, since the apex P1 on one end side and the apex P2 on the other end side of the light-shielding plate 86 are positioned on an imaginary circle Im1 along the outer periphery 861 of the light-shielding plate 86, it is possible to lengthen the circumferential length involved in blocking infrared light reception in the light-shielding plate 86. This makes it possible to appropriately process output signals when the operation dial 9 is operated at high speed, and is expected to reduce erroneous detection.

[0071] As described above, the switch device 1 according to the present embodiment includes the rotation sensor 10 having the following configuration. (1) The rotation sensor 10 includes an optical sensor 7 and a light blocking plate 86 . The optical sensor 7 includes a light emitting portion 71 and a pair of light receiving portions 72 (72a, 72b) disposed opposite the light emitting portion 71 with a gap therebetween. The light blocking plate 86 moves in the circumferential direction around the rotation axis X between the light emitting portion 71 and the pair of light receiving portions 72 (72a, 72b) in conjunction with the rotation of the operation dial 9 (rotating body). The pair of light receiving portions 72 (72a, 72b) are arranged in the circumferential direction around the rotation axis X. The light blocking plate 86 has a thickness in the radial direction of the rotation axis X, and has a predetermined length in the circumferential direction around the rotation axis X. The light blocking plate 86 is formed in a tapered shape on one end side and the other end side in the circumferential direction around the rotation axis X, so that the thickness in the radial direction of the rotation axis X becomes thinner.

[0072] With this configuration, it is possible to reduce the degree to which the timing at which the light is blocked by the light blocking plate 86 and the blocking is released fluctuates due to the influence of the radial thickness of the light blocking plate 86. This makes it possible to suppress the difference between the change in the output signal of the light receiving portion 72a and the change in the output signal of the light receiving portion 72b, so that the rotation of the rotating body can be appropriately detected from the output signals of the two light receiving portions 72a, 72b. In particular, the light-shielding plate 86 is formed in a tapered shape at one end and the other end in the circumferential direction around the rotation axis X, such that the thickness in the radial direction of the rotation axis X becomes thinner, thereby making it possible to clearly determine the timing at which the light-receiving unit 72 blocks reception of infrared light and the timing at which the light-receiving blockage is lifted.

[0073] (2) The vertex P1 on one end side of the light blocking plate 86 and the vertex P2 on the other end side of the light blocking plate 86 are located on a common imaginary circle Im1 with the rotation axis X as the center.

[0074] With this configuration, the timing at which the light is blocked by the light blocking plate 86 and the blocking is released can be converged to a desired timing. This allows the change in the output signal of the light receiving portion 72a and the change in the output signal of the light receiving portion 72b to be aligned, so that the rotation of the operation dial 9 (rotating body) can be appropriately detected from the output signals of the two light receiving portions 72a, 72b.

[0075] (3) When viewed from the direction of the rotation axis X, the pair of light receiving portions 72 (72a, 72b) are located on the outer diameter side of the light blocking plate 86. An outer periphery 861 of the light blocking plate 86 is located on a common imaginary circle Im1.

[0076] With this configuration, the timing at which the light reception is blocked by the light blocking plate 86 can be converged to a desired timing. Furthermore, a vertex P1 on one end side and a vertex P2 on the other end side are located on an imaginary circle Im1 along an outer periphery 861 of the light-shielding plate 86. Therefore, the light-shielding plate 86 blocks and cancels the blocking of received light near the light-receiving portions 72a and 72b. As a result, the changing waveform of the output signal from the light receiving portion 72a and the changing waveform of the output signal from the light receiving portion 72b converge to the same waveform, so that the rotation of the rotating body can be appropriately detected from the output signals from the two light receiving portions 72a, 72b.

[0077] In particular, the light receiving units 72a, 72b are adjacent to the light receiving units 72a, 72b, where the light blocking plate 86 blocks and clears the blocking. The rate of change in the output signal of the light receiving units 72a, 72b when the light receiving unit 72a, 72b is blocked and cleared increases as the position where the light receiving unit 86 blocks the light receiving (light blocking point) and the position where the light blocking is cleared (aperture point) get closer to the light receiving units 72a, 72b. When the rate of change of the output signal increases, the time it takes for the output signal to switch between High and Low becomes shorter. This shortens the time required to detect the rotation of the rotating body from the output signals of the two light receiving parts 72a and 72b, making it possible to properly detect the rotation of the rotating body even when the rotation speed of the rotating body increases.

[0078] (4) When the vertex P1 on one end side of the light-shielding plate 86 is positioned on the straight line Ln2 (first straight line) connecting the light-emitting unit 71 and the light-receiving unit 72b, the area on the rotation axis X side of the vertex P1 on one end side is positioned on the other end side of the straight line Ln2 (the left side in FIG. 6B). When the vertex P2 on the other end side of the light-shielding plate 86 is positioned on the straight line Ln1 (second straight line) connecting the light-emitting portion 71 and the light-receiving portion 71a, the area on the rotation axis X side of the vertex P2 on the other end side is positioned on the one-end side (the right side in (C) of Figure 6) of the straight line Ln1.

[0079] With this configuration, only the vertices P1 and P2 located on the common imaginary circle Im1 can be involved in blocking and canceling the reception of infrared light at the light receiving portions 72a and 72b. This allows the change in the output signal of the light receiving portion 72a and the change in the output signal of the light receiving portion 72b to be aligned, so that the rotation of the rotating body can be appropriately detected from the output signals of the two light receiving portions 72a, 72b.

[0080] The present invention can also be specified as a switch device 1 that employs the rotation sensor 10 described above in (1) to (4). (5) The switch device 1 is An operation dial 9 rotatable around a rotation axis X; The rotation sensor 10 of (1) to (4) described above, A main body case 2 (case) that rotatably supports an operation dial 9; A substrate 6 on which an optical sensor 7 is mounted, The rotating body 8 connected to the operation dial 9 has a support portion 85 (a cylindrical portion) surrounding the rotation axis X. The light blocking plate 86 is provided at a portion of the support portion 85 facing the substrate 6 .

[0081] With this configuration, the rotation of the operation dial 9 can be appropriately detected from the output signals of the two light receiving portions 72a, 72b of the optical sensor .

[0082] (6) The light blocking plates 86 are provided at predetermined intervals in the circumferential direction around the rotation axis X over the entire circumference of the support portion 85 (cylindrical portion).

[0083] With this configuration, one or more rotations of the operation dial 9 can be appropriately detected.

[0084] FIGS. 10A to 10C are diagrams illustrating light shielding plates 86B, 86C, and 86D according to modified examples. In the embodiment described above, the light-shielding plate 86 is formed in a tapered shape such that one end side and the other end side in the circumferential direction around the rotation axis X become thinner in the radial direction of the rotation axis X, and the apex P1 on the one end side and the apex P2 on the other end side are located on a virtual circle Im1 whose diameter is smaller than the virtual circle Im0 that follows the outer periphery of the support portion 85. The shape of the light shielding plate is not limited to the shape shown in the embodiment, and may be changed as appropriate as long as the shape can converge the timing at which the light shielding plate blocks the received light and the timing at which the blocking is released to the desired timing. For example, as shown in FIG. 10A, a light blocking plate 86B may be configured such that a vertex P5 on one end side and a vertex P6 on the other end side are located on an imaginary circle Im4 passing between an outer periphery 861 and an inner periphery 862. In this case as well, the timing at which the light reception at the light receiving sections 72a and 72b is blocked and the timing at which the blocking is released can be made to converge to the desired timing.

[0085] 10B, an elliptical light-shielding plate 86C may be used. In this case, too, the apex P7 on one end side and the apex P8 on the other end side are located on a common imaginary circle Im5, so that the timing at which light reception is blocked by the light-receiving units 72a and 72b and the timing at which the blocking is released can be converged to the desired timing.

[0086] 10C, a light blocking plate 86D may be a substantially trapezoidal shape in which the length L861 of the outer periphery 861 is shorter than the length L862 of the inner periphery 862. In this case, by forming one side 863 and the other side 864 in the circumferential direction into shapes that follow the straight lines Ln1 and Ln2 that connect the light emitter 71 and the light receiver 72 (72a, 72b), respectively, it is possible to converge the timing at which light reception is blocked by the light receivers 72a and 72b and the timing at which the blocking is lifted to the desired timing.

[0087] Furthermore, the light blocking plate may be formed in a triangular shape with vertices P1, P2 connected to a point on the inner periphery of the light blocking plate.

[0088] In the above embodiment, the pair of light receiving units 72 (72a, 72b) are located on the outer diameter side of the movement trajectory of the light blocking plate 86. Therefore, the vertices P1 and P2 of the light blocking plate 86 are configured to be located on a virtual circle Im1 along the outer periphery 861 close to the light receiving unit 72. When a pair of light receiving portions 72 (72a, 72b) are located on the inner diameter side of the movement trajectory of the light shielding plate 86, the vertices P1 and P2 of the light shielding plate 86 are positioned on a virtual circle Im3 (Figure 3 (A)) along the inner circumference 862 close to the light receiving portion 72.

[0089] Although the embodiment and modified examples of the present invention have been described above, the present invention is not limited to these and can be modified as appropriate within the scope of the technical concept of the invention. [Explanation of symbols]

[0090] 1: Switch device 2: Main body case 3: Body 4: Front cover 5: Rear cover 6: Substrate 7: Optical sensor 71: Light emitting part 72 (71a, 71b): Light receiving section 8: Rotating body 81: 1st cylindrical part 82:Second cylinder part 83: Connection 84: Flange part 85: Support part 86, 86A~86D: Light shielding plate 861: Outer circumference 862: Inner circumference 863 :One side 864: Other side 9: Operation dial 10: Rotation sensor Im1~Im5: Virtual circle P1~P8: Vertices W86: Thickness X: Rotation axis

Claims

1. an optical sensor including a light emitting unit and a pair of light receiving units disposed opposite the light emitting unit with a gap therebetween; a light-shielding plate that moves in a circumferential direction around a rotation axis between the light-emitting unit and the pair of light-receiving units in conjunction with the rotation of a rotating body, The pair of light receiving portions are arranged in a circumferential direction around the rotation axis, the light blocking plate has a thickness in a radial direction of the rotation shaft and a predetermined length in a circumferential direction around the rotation shaft, A rotation sensor, wherein the light-shielding plate is formed in a tapered shape at one end side and the other end side in a circumferential direction around the rotation shaft, so that the thickness in a radial direction of the rotation shaft becomes thinner.

2. The rotation sensor according to claim 1 , wherein the one end of the light-shielding plate and the other end of the light-shielding plate are positioned on a common imaginary circle centered on the rotation axis.

3. The pair of light receiving units are located on the outer diameter side of the light blocking plate, The rotation sensor according to claim 2 , wherein an outer periphery of said light blocking plate is positioned on said common imaginary circle.

4. the one end side of the light-shielding plate is shaped such that, when the one end is positioned on a first straight line connecting the light-emitting unit and one of the pair of light-receiving units, a region closer to the rotation axis than the one end is positioned closer to the other end than the first straight line, A rotation sensor as described in any one of claims 1 to 3, wherein the other end side of the light-shielding plate is shaped such that when the other end is positioned on a second straight line connecting the light-emitting unit and the other of the pair of light-receiving units, the area closer to the rotation axis than the other end is positioned closer to the one end side than the second straight line.

5. A switch device employing the rotation sensor according to any one of claims 1 to 4, An operation dial that is rotatable around the rotation axis; a case that rotatably supports the operation dial; A substrate on which the optical sensor is mounted; The operation dial has a cylindrical portion surrounding the rotation shaft, The light blocking plate is provided on a portion of the cylindrical portion facing the substrate.

6. The switch device according to claim 5 , wherein the light blocking plates are provided around the entire circumference of the cylindrical portion at predetermined intervals in a circumferential direction around the rotation shaft.

Images