JP2021078174A - Rotary drive device and vehicular pointer instrument - Google Patents

Abstract

To prevent a press-fit load of a rotor from being reduced by a press-fit fixing part even in the case where an oil sneaks into an inner peripheral surface of an output shaft before inserting the rotor to the output shaft.SOLUTION: An output shaft 637 is formed in a cylindrical shape including an insertion hole 637 in which a rotor 4 can be inserted, and rotationally driven by a drive source D. A bearing 85 supports the output shaft 637 from an outer peripheral side in such a manner that the output shaft can be slid. The output shaft 637 is provided on an inner peripheral surface forming the insertion hole 637a and includes a press-fit fixing part 81 by which the rotor 4 is press-fitted and fixed in a rotatable manner integrally with the output shaft 637. The press-fit fixing part 81 includes six grooves 86a-86f, 86g-86l and 86m-86r extending in a direction along a rotation axis of the output shaft 637.SELECTED DRAWING: Figure 5

Description

The present disclosure relates to a rotary drive device.

Patent Document 1 discloses a rotation drive device used for a vehicle pointer instrument and rotationally drives a rotation pointer. This rotary drive device includes a drive source, a speed reduction mechanism, and a rotary output mechanism housed in a casing. The rotation output mechanism has a cylindrical output shaft, and is inserted into the insertion hole of the output shaft so that the rotation axis of the rotation pointer is coaxial. The rotation shaft of the rotation pointer is press-fitted and fixed by a press-fit fixing portion formed on a part of the inner peripheral surface of the output shaft forming the insertion hole, and the rotation pointer can rotate integrally with the output shaft.

The casing has a bearing. The output shaft is fitted on the inner peripheral side of the bearing so as to be relatively slidable. Oil is applied to the bearings to enable such relative sliding.

Special Table 2018-182911

However, in the above-mentioned rotary drive device, the oil applied to the bearing is transmitted to the inner peripheral surface of the output shaft through innumerable shallow scratches generated on the outer peripheral surface of the output shaft during molding of the output shaft, for example, due to the capillary phenomenon. It may wrap around and adhere to the press-fitting fixing part. Then, as a result of detailed examination by the inventor, if oil adheres to the press-fitting and fixing portion before the rotation pointer is inserted into the output shaft, the press-fitting load by the press-fitting and fixing portion of the rotation pointer decreases, and the rotation due to the idling of the rotation pointer decreases. A problem has been found in which the guideline is likely to be misaligned.

One aspect of the present disclosure is to suppress a decrease in the press-fitting load of the rotating body by the press-fitting fixing portion even when oil wraps around the inner peripheral surface of the output shaft before inserting the rotating body into the output shaft. It is an object.

One aspect of the present disclosure is a rotary drive device (6) that rotationally drives a rotating body (4), and includes a drive source (63, D), an output shaft (637), and a bearing (85). .. The output shaft has a tubular shape having an insertion hole (637a) into which a rotating body can be inserted, and is rotationally driven by a drive source. The bearing supports the output shaft so as to be slidable from the outer peripheral side. The output shaft is provided on an inner peripheral surface forming an insertion hole, and has a press-fit fixing portion (81) for rotatably press-fixing the rotating body integrally with the output shaft. The press-fitting fixing portion has at least one groove (86a to 86f, 86g to 86l, 86m to 86r) extending in a direction along the rotation axis of the output shaft.

According to such a configuration, even if oil wraps around the inner peripheral surface of the output shaft before the rotating body is inserted into the output shaft, it is possible to prevent the press-fitting load of the rotating body from being reduced by the press-fitting fixing portion. Can be done.

One aspect of the present disclosure is a vehicle pointer instrument (1), which includes the above-mentioned rotary drive device (6) and a pointer (4). The pointer is a rotating body that indicates a value indicating the state of the vehicle according to the rotation position driven by the rotation drive device.

It is a front view which shows the pointer instrument for a vehicle. FIG. 2 is a sectional view taken along line II-II of FIG. It is an exploded perspective view which shows the rotation drive device. It is a perspective view which shows the inside of the rotation drive device. It is sectional drawing which shows the tip of the output shaft and a part of a part of the 1st case member enlarged. It is a top view which shows the output axis. It is sectional drawing which shows the base end of an output shaft and a part of a part of the 2nd case member in an enlarged manner. It is a schematic diagram which shows the modification of the output shaft which the groove is formed into a semicircular shape. It is a schematic diagram which shows the modification of the output shaft in which a groove is formed in a triangular shape.

Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings.
[1. Constitution]
[1-1. overall structure]
The vehicle pointer instrument 1 shown in FIGS. 1 and 2 is installed on an instrument panel in the vehicle. The vehicle pointer instrument 1 includes a display member 2, a rotation pointer 4, and a rotation drive device 6. In the following description, the "visual side" means the side in which the display of the vehicle pointer instrument 1 is visually recognized by the occupant on the driver's seat, and the "non-visual side" means the "visible side". Means the opposite side.

The display member 2 is a flat plate-like member in which a light-shielding printing layer is laminated on a translucent base material such as a polycarbonate resin. The display surface 2a, which is one surface of the display member 2, is arranged toward the viewing side. The back surface 2b, which is the surface of the display member 2 opposite to the display surface 2a, is arranged toward the non-visual side. As shown in FIG. 1, the open portion of the light-shielding printing layer in the display member 2 is a number and a scale arranged in the rotation direction of the rotation pointer 4 in order to display the "vehicle state value" which is a value indicating the state of the vehicle. Is formed as an index 20. Here, the "vehicle state value" of the present embodiment is a vehicle speed value, but the "vehicle state value" may be a physical quantity such as an engine speed related to the vehicle.

The rotation pointer 4 is formed of a translucent resin material such as acrylic resin, and has a pointer body 40 and a rotation shaft 41. The pointer body 40 is an elongated needle-shaped member, and is arranged on the visual side of the display member 2 on the visual side of the display surface 2a. The pointer main body 40 indicates the "vehicle state value" represented by the index 20 by the tip 40a of the pointer main body 40 according to the rotation position. As shown in FIGS. 1 and 2, the rotating shaft 41 is a columnar member extending from the base end 40b, which is the end opposite to the tip 40a of the pointer body 40, to the non-visual side. The rotating shaft 41 is inserted into the pointer hole 22 formed in the display member 2 so as to penetrate the display surface 2a and the back surface 2b. The rotary shaft 41 is connected to the rotary drive device 6 on the non-visual side of the back surface 2b of the display member 2. As a result, the rotation driving device 6 realizes the above-mentioned instruction by the pointer main body 40 by rotationally driving the rotation pointer 4 around the rotation center line C, which is the axis of the rotation shaft 41.

As shown in FIG. 2, the rotation driving device 6 is arranged on the non-visual side of the back surface 2b of the display member 2. The rotation drive device 6 includes a casing 60 and a device body 63.
As shown in FIGS. 2 and 3, the casing 60 is formed of a light-shielding resin material such as a modified polyphenylene ether resin (m-PPE) in a hollow shape so as to accommodate the apparatus main body 63, and the first case member 61 and the first case member 61 It has a two-case member 62. The case members 61 and 62 are formed in a cup shape, and the opening edges 610 and 620 are overlapped with each other and are connected to each other by snap-fit fitting. Each case member 61, 62 has through holes 612,622 penetrating the bottom portions 611, 621 on the rotation center line C of the rotation shaft 41, respectively. The first case member 61 is arranged so as to face the back surface 2b on the non-visual side of the display member 2. The second case member 62 is arranged on the anti-visual side with respect to the first case member 61.

As shown in FIGS. 2 to 4, the apparatus main body 63 is housed in the casing 60. The apparatus main body 63 includes a drive source D, a deceleration mechanism R, and a rotation output mechanism O. In the following description, the axial direction along the rotation center line C, the radial direction substantially perpendicular to the rotation center line C, and the circumferential direction around the rotation center line C are simply referred to as the axial direction, the radial direction, and the circumferential direction, respectively. ..

In this embodiment, a step motor is used as the drive source D. The drive source D includes a yoke 630, two-phase coils 631a and 631b, and a magnet rotor 632, and is arranged so as to deviate from the rotation center line C of the rotation shaft 41 in the radial direction. The yoke 630 is formed in a frame shape by a magnetic metal material such as iron, and is fixed to the casing 60. The yoke 630 has a pair of magnetic poles 630a and 630b protruding toward the inner peripheral side. A phase A coil 631a is wound around one magnetic pole 630a, and a B phase coil 631b is wound around the other magnetic pole 630b. The A-phase coil 631a and the B-phase coil 631b are electrically connected to a metal wiring layer of a substrate (not shown) on which the apparatus main body 63 is mounted through a through hole penetrating the second case member 62 of the casing 60. It is connected.

The magnet rotor 632 is formed in a disk shape by a magnetic metal material such as ferrite, and is arranged in the frame of the yoke 630 with a gap between the magnetic poles 630a and 630b. The magnet rotor 632 is supported by the casing 60 from the radial direction and the thrust direction so as to be rotatable around an axis substantially parallel to the rotation center line C of the rotation shaft 41. N and S poles as magnetic poles are alternately magnetized in the rotation direction on the outer peripheral portion of the magnet rotor 632.

In the drive source D having such a configuration, the A-phase coil 631a and the B-phase coil 631b are 90 degrees in phase with each other from an external control circuit via a metal wiring layer of a substrate on which the apparatus main body 63 is mounted. The shifted AC signal is applied. As a result, the AC magnetic flux generated in the A-phase coil 631a and the B-phase coil 631b passes between the yoke 630 and the magnet rotor 632 to drive the magnet rotor 632 to a predetermined rotation position. ..

The reduction mechanism R includes a magnet gear 634, an idle gear 635, and a pinion gear 636, and is arranged so as to deviate from the rotation center line C of the rotation shaft 41 in the radial direction. The magnet gear 634 is formed in a spur gear shape by a hard resin material such as polyacetal resin (POM), and is supported by a casing 60 from the radial direction and the thrust direction so as to be integrally rotatable with the magnet rotor 632.

The idle gear 635 and the pinion gear 636 are integrally formed coaxially with a hard resin material such as polybutylene terephthalate resin (PBT), and each is formed in the shape of a spur gear. The idle gear 635 and the pinion gear 636 are supported by the casing 60 from the radial direction and the thrust direction so as to be integrally rotatable around an axis substantially parallel to the rotation center line C of the rotation shaft 41. The idle gear 635 meshes with the magnet gear 634 to reduce the rotation of the magnet gear 634.

The rotation output mechanism O includes an output shaft 637, an output gear 638, a rotation stopper 639, a washer 90, and an urging member 89, and is arranged on the rotation center line C of the rotation shaft 41. The output shaft 637, the output gear 638, and the rotation stopper 639 are integrally formed of a hard resin material such as polyacetal resin (POM). The output shaft 637, the output gear 638, and the rotation stopper 639 are supported by the casing 60 from the radial direction and the thrust direction so as to be integrally rotatable around the rotation center line C of the rotation shaft 41.

The output shaft 637 is a tubular member having an insertion hole 637a into which the rotation pointer 4 can be inserted. In the present embodiment, the output shaft 637 is formed in a cylindrical shape so that the insertion hole 637a has a circular shape. The rotation shaft 41 of the rotation pointer 4 is coaxially press-fitted into the insertion hole 637a of the output shaft 637. As a result, the output shaft 637 rotates around the rotation center line C together with the rotation pointer 4, and outputs a rotation driving force to the rotation pointer 4.

The output gear 638 is a spur gear-shaped member that extends in the radial direction from the outer peripheral surface of the output shaft 637. The output gear 638 meshes with the pinion gear 636 of the reduction mechanism R to reduce the rotation of the pinion gear 636. From the above configuration, in the apparatus main body 63, the rotational driving force increased by the deceleration action of the deceleration mechanism R from the drive source D is applied from the rotational output mechanism O to the rotational pointer 4.

The rotation stopper 639 is a projecting piece-shaped member that protrudes from the output gear 638 toward the visual recognition side. The rotation stopper 639 is provided so as to be lockable by a fixing stopper (not shown) of the casing 60 at the limit positions on both sides that determine the rotation range of the rotation pointer 4. As a result, even if a rotation driving force is applied from the rotation output mechanism O to the rotation pointer 4, the rotation of the rotation pointer 4 outside the rotation range is restricted.

The washer 90 is made of a hard resin material such as polyacetal resin (POM) and is formed in a ring flat plate shape into which an output shaft 637 can be inserted. The washer 90 is arranged coaxially with the output shaft 637. The washer 90 is assembled between the first case member 61 and the output gear 638 so as to come into contact with the first case member 61.

The urging member 89 is a leaf spring formed in a square shape by an elastic metal material such as stainless steel (SUS). The urging member 89 has a circular hole in the center of the urging member 89 into which the output shaft 637 can be inserted, and is arranged coaxially with the output shaft 637. The urging member 89 is assembled between the first case member 61 and the output gear 638 so as to come into contact with the output gear 638. The urging member 89 is elastically deformed in a state where it can rotate integrally with the output gear 638 by being sandwiched and compressed by the bottom portion 611 of the first case member 61 and the output gear 638 together with the washer 90. There is. As a result, the urging member 89 urges the output shaft 637 to the non-visual side regardless of the rotational positions of the output gear 638 and the output shaft 637. The washer 90 reduces the frictional resistance at the time of rubbing with the urging member 89 to suppress the wear of the urging member 89.

[1-2. Detailed configuration of output shaft]
Next, the output shaft 637 will be described in detail with reference to FIGS. 5 to 7.
The output shaft 637 has a tip end 637b and a base end 637c. As shown in FIG. 5, the tip 637b of the output shaft 637 is an end on the side where the rotation pointer 4 is inserted, in other words, an end on the side facing the bottom 611 of the first case member 61.

The tip 637b of the output shaft 637 is inserted into the through hole 612 of the first case member 61. The tip 637b of the output shaft 637 forms a top 80 by its end face. In this embodiment, the insertion hole 637a is open at the top 80. The top portion 80 has a width in the radial direction and is formed in a circular planar shape continuous in the circumferential direction. In other words, the top 80 is an annular surface parallel to the direction perpendicular to the center of rotation C.

The output shaft 637 has a press-fitting fixing portion 81 and a guide portion 82 formed at different positions in the axial direction of the insertion hole 637a. The press-fit fixing portion 81 and the guide portion 82 are provided on the inner peripheral surface of the output shaft 637 forming the insertion hole 637a.

The press-fit fixing portion 81 is provided at a position at a certain distance from the top 80 on the non-visual side. The press-fit fixing portion 81 is formed on the inner peripheral surface of the output shaft 637, and is a portion of the entire circumferential direction including a portion protruding toward the rotation center line C. As shown in FIG. 6, in the present embodiment, the press-fitting fixing portion 81 has six protruding portions 81a to 81f projecting toward the rotation center line C and six grooves 86a to 86f extending in the axial direction. .. The six protrusions 81a to 81f and the six grooves 86a to 86f are formed at intervals in the rotation direction of the output shaft 637 and in the circumferential direction in the present embodiment. In the present embodiment, the six protrusions 81a to 81f and the six grooves 86a to 86f are formed at equal intervals in the circumferential direction. That is, the six protrusions 81a to 81f and the six grooves 86a to 86f are arranged alternately side by side in the circumferential direction. The six protrusions 81a to 81f and the six grooves 86a to 86f have first curved surfaces 811a to 811f and second curved surfaces 866a to 866f that are curved with the same curvature as the inner peripheral surface of the output shaft 637, respectively. The inner diameter of the cylindrical hole formed along the first curved surfaces 811a to 811f is set to be smaller than the inner diameter of the cylindrical hole formed along the second curved surfaces 866a to 866f. The inner diameter of the cylindrical hole formed along the first curved surfaces 811a to 811f and the inner diameter of the cylindrical hole formed along the second curved surfaces 866a to 866f are the inner diameters of the inner peripheral side edge 800 at the top 80. It is set to a smaller diameter than. The first curved surfaces 811a to 811f and the second curved surfaces 866a to 866f are continuously formed by two surfaces extending from the second curved surfaces 866a to 866f toward the rotation center line C. As a result, a tubular hole having two inner diameters extending straight along the axial direction is formed. In the present embodiment, the six grooves 86a to 86f are U-shaped, specifically, roughly trapezoidal grooves, respectively, when the six protrusions 81a to 81f are projected onto a plane orthogonal to the rotation center line C. Is.

A part of the rotation pointer 4 in the axial direction of the rotation shaft 41 is coaxially inserted into the press-fit fixing portion 81, and the press-fit fixing portion 81 is in surface contact with the outer peripheral surface of the rotation shaft 41. Specifically, the first curved surfaces 811a to 811f of the six protrusions 81a to 81f and the outer peripheral surface of the rotating shaft 41 are in surface contact with each other. That is, in the surface contact, in the present embodiment, the outer peripheral surface of the rotating shaft 41 and the first curved surfaces 811a to 811f curved with the same curvature as the outer peripheral surface are in contact with each other. In the press-fitting fixing portion 81 of the present embodiment, a rotating shaft 41 formed to have a diameter larger than the inner diameter of the six first curved surfaces 811a to 811f before insertion is inserted with a press-fitting allowance. That is, the rotary shaft 41 is press-fitted and fixed to the press-fitting and fixing portion 81. As a result, the rotation pointer 4 can rotate integrally with the output shaft 637.

As shown in FIG. 5, the guide portion 82 is provided between the top portion 80 and the press-fit fixing portion 81. The guide portion 82 is formed in a stepped manner on the inner peripheral surface of the output shaft 637. As a result, the guide portion 82 forms two inner peripheral tapered portions 820 and 822 and an inner peripheral straight portion 821. Here, the first inner peripheral tapered portion 820 is a portion whose diameter is gradually reduced in a tapered shape from the inner peripheral side edge portion 800 of the top portion 80 to the press-fit fixing portion 81 on the inner peripheral side in the axial direction. A conical hole is formed by the first inner peripheral tapered portion 820. The inner peripheral straight portion 821 is a portion extending straight along the axial direction from the anti-visual side end (that is, the inner peripheral side edge portion) of the first inner peripheral tapered portion 820. A cylindrical hole is formed by the inner peripheral straight portion 821. The diameter of the second inner peripheral tapered portion 822 is gradually reduced as it approaches the six protruding portions 81a to 81f of the press-fit fixing portion 81 on the inner peripheral side from the non-visual side end of the inner peripheral straight portion 821 in the axial direction. It is the part to do. A roughly conical hole is formed by the second inner peripheral tapered portion 822. In the present embodiment, the portion of the inner peripheral straight portion 821 that is axially close to the six grooves 86a to 86f of the press-fit fixing portion 81 from the non-visual side end continues to be straightly stretched as it is without reducing the diameter. That is, the second curved surfaces 866a to 866f of the six grooves 86a to 86f are set to have the same inner diameter as the inner peripheral straight portion 821 of the guide portion 82. In other words, the second curved surfaces 866a to 866f and the inner peripheral straight portion 821 are formed in the same plane.

The output shaft 637 further has an outer peripheral straight portion 83 and an outer peripheral tapered portion 84 formed at different positions in the axial direction on the outer peripheral side of the top 80 of the tip 637b. The outer peripheral straight portion 83 and the outer peripheral tapered portion 84 are provided on the outer peripheral surface of the output shaft 637.

The outer peripheral straight portion 83 is provided at a position at a certain distance from the top portion 80 on the non-visual side. The outer peripheral straight portion 83 is a portion that extends straight along the axial direction. The outer peripheral straight portion 83 forms a cylindrical outer peripheral surface. The outer diameter of the outer peripheral straight portion 83 is set to be larger than the outer diameter of the outer peripheral side edge portion 801 at the top portion 80. The outer peripheral tapered portion 84 is provided between the top portion 80 and the outer peripheral straight portion 83. The outer peripheral tapered portion 84 is a portion whose diameter is gradually increased in a tapered shape from the outer peripheral side edge portion 801 of the top portion 80 to the outer peripheral straight portion 83 on the outer peripheral side in the axial direction. The outer peripheral tapered portion 84 forms a conical outer peripheral surface.

As shown in FIG. 7, the base end 637c of the output shaft 637 is an end portion of the second case member 62 on the side facing the bottom portion 621. The base end 637c of the output shaft 637 is inserted into the through hole 622 of the second case member 62. The base end 637c of the output shaft 637 forms an annular planar end face 88 having a width in the radial direction and continuous in the circumferential direction due to the end face thereof.

[1-3. Detailed casing configuration]
Next, the casing 60 will be described in detail with reference to FIGS. 5 and 7.
As shown in FIG. 5, the first case member 61 of the casing 60 has a radial bearing 85 that forms a part of a through hole 612 that coaxially surrounds the output shaft 637.

The radial bearing 85 is provided at a position at a certain distance from the outer surface 611a, which is the end surface of the portion of the bottom portion 611 of the first case member 61 that protrudes to the visible side, to the non-visual side. The radial bearing 85 is a portion formed on the inner peripheral surface of the first case member 61 and extending straight along the axial direction. A cylindrical hole is formed by the radial bearing 85. The inner diameter of the radial bearing 85 is set to be smaller than the inner diameter of the other portion forming the through hole 612 located on the anti-visual side of the radial bearing 85 in the axial direction. In the cylindrical hole formed by the radial bearing 85 in the through hole 612, a part of the outer peripheral straight portion 83 of the output shaft 637 on the visual side of the output gear 638 is coaxially inserted. In the present embodiment, in the cylindrical hole formed by the radial bearing 85 in the through hole 612, an outer peripheral straight portion 83 formed having a diameter slightly smaller than that of the radial bearing 85 is fitted so as to be relatively slidable. As a result, the radial bearing 85 supports the output shaft 637 in the radial direction from the outer peripheral side. The radial bearing 85 comes into contact with the outer peripheral straight portion 83 with silicon oil interposed therebetween.

As shown in FIG. 7, the second case member 62 of the casing 60 has a tubular portion 624 protruding from the bottom portion 621 toward the visual recognition side. The tubular portion 624 has a thrust bearing 87 that forms a part of a through hole 622 that coaxially surrounds the output shaft 637.

The thrust bearing 87 is provided in a predetermined range from the bottom surface 870, which is in contact with the end surface 88 of the base end 637c of the output shaft 637, on the surface of the bottom portion 621 of the second case member 62. The bottom surface 870 is formed on the inner peripheral surface of the second case member 62, and is formed in a ring plane shape having a width in the radial direction and continuous in the circumferential direction. The thrust bearing 87 is a portion that extends straight along the axial direction. A bottomed cylindrical hole is formed by the thrust bearing 87 and the bottom surface 870. The inner diameter of the thrust bearing 87 is set to be larger than the inner diameter of the inner peripheral side edge portion 871 of the bottom surface 870.

A part of the outer peripheral straight portion 83 of the output shaft 637 on the non-visual side of the output gear 638 is coaxially inserted into the bottomed cylindrical hole formed by the thrust bearing 87 in the through hole 622. In the present embodiment, in the bottomed cylindrical hole formed by the thrust bearing 87 among the through holes 622, an outer peripheral straight portion 83 formed having a diameter slightly smaller than that of the thrust bearing 87 is fitted so as to be relatively slidable. There is. Further, in the present embodiment, the end surface 88 of the base end 637c of the output shaft 637 is in contact with the bottom surface 870 in a relative slidable surface contact state. As described above, the thrust bearing 87 supports the output shaft 637 in the radial direction from the outer peripheral side, and the bottom surface 870 supports the base end 637c of the output shaft 637 in the thrust direction from the visible side.

[2. effect]
According to the embodiment described in detail above, the following effects can be obtained.
(2a) In the present embodiment, the press-fit fixing portion 81 has six grooves 86a to 86f extending in the axial direction. As a result, the silicone oil applied to the radial bearing 85 is transmitted to the inner peripheral surface of the output shaft 637 through innumerable shallow scratches generated on the outer peripheral surface of the output shaft 637 during molding of the output shaft 637, for example, due to the capillary phenomenon. Even when it wraps around, it is possible to discharge the silicone oil through the six grooves 86a to 86f.

Specifically, the silicone oil that wraps around the inner peripheral surface of the output shaft 637 passes through the guide portion 82 and is the second of each of the six grooves 86a to 86f formed in the same plane as the inner peripheral straight portion 821. It is discharged in the axial direction along the curved surfaces 866a to 866f. Therefore, it is possible to suppress the adhesion of silicone oil to the first curved surfaces 811a to 811f of the six protruding portions 81a to 81f located on the inner peripheral side of the second curved surfaces 866a to 866f. is there. That is, it is possible to prevent the silicone oil that wraps around the inner peripheral surface of the output shaft 637 before inserting the rotating shaft 41 from adhering to the surface of the press-fitting fixing portion 81 that press-fits and fixes the outer peripheral surface of the rotating shaft 41. Is. In other words, even if the silicone oil wraps around the inner peripheral surface of the output shaft 637 before the rotary shaft 41 is inserted, the rotary shaft 41 is press-fitted and fixed by the press-fitting fixing portion 81 in a state where the silicone oil is suppressed from passing through. It is possible to do. Therefore, even if the silicone oil wraps around the inner peripheral surface of the output shaft 637 before the rotation pointer 4 is inserted into the output shaft 637, it is possible to prevent the press-fitting load of the rotation pointer 4 from being lowered by the press-fitting fixing portion 81. Can be done. Then, it is possible to prevent the rotation guideline 4 from being instructed to deviate due to the idling of the rotation guideline 4 caused by the decrease in the press-fitting load.

(2b) In the present embodiment, the first curved surfaces 811a to 811f of the six protruding portions 81a to 81f and the outer peripheral surface of the rotating shaft 41 are in surface contact with each other. As a result, for example, as compared with the configuration in which the press-fitting fixing portion 81 is in point contact with the outer peripheral surface of the rotating shaft 41, the silicon oil rotates on the inner peripheral surface of the output shaft 637 while press-fitting and fixing the rotating shaft 41 more firmly. Even when it is pushed in, it is possible to suppress a decrease in the press-fitting load of the rotation pointer 4 by the press-fitting fixing portion 81.

(2c) In the present embodiment, the six grooves 86a to 86f are formed at equal intervals in the circumferential direction. As a result, it is possible to facilitate the discharge of the silicone oil from any position in the circumferential direction with respect to the silicone oil that has wrapped around the inner peripheral surface of the output shaft 637. That is, since the positions of scratches generated on the outer peripheral surface of the output shaft 637 are likely to vary, the timing at which the silicone oil reaches the inner peripheral surface of the output shaft 637 is different on the outer peripheral surface of the output shaft 637. Therefore, no matter from which position in the circumferential direction the silicone oil wraps around the inner peripheral surface of the output shaft 637, the silicone oil can be discharged from the groove close to the position. Therefore, it is possible to easily discharge the silicone oil from any position in the circumferential direction with respect to the silicone oil that has wrapped around the inner peripheral surface of the output shaft 637.

In this embodiment, the rotation pointer 4 corresponds to a rotating body, and the radial bearing 85 corresponds to a bearing.
[3. Other embodiments]
Although the embodiments of the present disclosure have been described above, it goes without saying that the present disclosure is not limited to the above-described embodiments and can take various forms.

(3a) In the above embodiment, the six grooves 86a to 86f are U-shaped grooves when the six protrusions 81a to 81f are projected onto a plane orthogonal to the rotation center line C, respectively. The shape of the groove is not limited to this. For example, as shown in FIG. 8, each of the six grooves 86g to 86l may be a semicircular groove when the six protrusions 81g to 81l are projected onto a plane orthogonal to the rotation center line C. .. Further, for example, as shown in FIG. 9, the six grooves 86m to 86r are V-shaped, specifically, when the six protrusions 81m to 81r are projected onto a plane orthogonal to the rotation center line C, respectively. It may be a triangular groove.

(3b) The number of grooves included in the press-fit fixing portion 81 is not limited to six, and may be one or more and five or less, or seven or more.
(3c) The functions of one component in the above embodiment may be dispersed as a plurality of components, or the functions of the plurality of components may be integrated into one component. Further, a part of the configuration of the above embodiment may be omitted. Further, at least a part of the configuration of the above embodiment may be added or replaced with the configuration of the other embodiment.

4 ... Rotation pointer, 6 ... Rotation drive device, 81 ... Press-fit fixing part, 81a to 81f, 81g to 81l, 81m to 81r ... Protruding part, 85 ... Radial bearing, 86a to 86f, 86g to 86l, 86m to 86r ... Groove , 637 ... Output shaft, 637a ... Insert hole.

Claims (5)

A rotary drive device (6) that rotationally drives a rotating body (4).
Drive source (63, D) and
A tubular output shaft (637) having an insertion hole (637a) into which the rotating body can be inserted, and being rotationally driven by the drive source, and an output shaft (637).
A bearing (85) that slidably supports the output shaft from the outer peripheral side,
With
The output shaft is provided on an inner peripheral surface forming the insertion hole, and has a press-fit fixing portion (81) for rotatably press-fixing the rotating body integrally with the output shaft.
The press-fitting fixing portion is a rotation driving device having at least one groove (86a to 86f, 86g to 86l, 86m to 86r) extending in a direction along the rotation axis of the output shaft. The rotary drive device according to claim 1.
The press-fitting fixing portion is a rotation driving device that makes surface contact with the outer peripheral surface of the rotating body. The rotary drive device according to claim 1 or 2.
A rotation driving device in which two or more of the at least one grooves are formed in the press-fitting fixing portion at intervals in the rotation direction of the output shaft. The rotary drive device according to any one of claims 1 to 3.
A rotary drive device in which a step motor is used as the drive source. The rotary drive device (6) according to any one of claims 1 to 4, and the rotary drive device (6).
A pointer (4), which is a rotating body that indicates a value indicating a state of the vehicle according to a rotation position driven by the rotation drive device, and a pointer (4).
A vehicle pointer instrument (1).

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