CN111094902B

CN111094902B - Mounting mechanism and motor using the same

Info

Publication number: CN111094902B
Application number: CN201880059357.3A
Authority: CN
Inventors: 大久保将克
Original assignee: Panasonic Intellectual Property Management Co Ltd
Current assignee: Panasonic Intellectual Property Management Co Ltd
Priority date: 2017-09-20
Filing date: 2018-09-10
Publication date: 2022-03-22
Anticipated expiration: 2038-09-10
Also published as: WO2019059010A1; CN111094902A; JP7113237B2; JPWO2019059010A1

Abstract

The installation mechanism includes: a 1 st nut including a cylindrical portion through which the rotating shaft passes, the cylindrical portion extending along an axis of the rotating shaft and having a 1 st outer circumferential surface including a 1 st thread, and a flange portion protruding in a direction intersecting the axis and in a direction opposite to a side where the rotating shaft is located and having a 1 st inner circumferential surface including a 1 st thread groove; a 2 nd nut through which a rotation shaft passes, the 2 nd nut including a 2 nd thread groove and a small hole portion, the 2 nd thread groove being formed in a part of a 2 nd inner peripheral surface facing the rotation shaft and being screw-coupled to the 1 st thread ridge, the small hole portion being formed in a part of the 2 nd inner peripheral surface other than the 2 nd thread groove and being fitted to the rotation shaft; and an annular body through which the rotating shaft passes and which is located between the rotating shaft and a 3 rd inner circumferential surface of the cylindrical portion, wherein the annular body has a 1 st inclined surface, and when the 1 st nut and the 2 nd nut are screwed together in a direction in which they approach each other, the 1 st inclined surface converts a force acting in a direction along the axis, which is applied from each of the 1 st nut and the 2 nd nut, into a force acting in a direction intersecting the axis.

Description

Mounting mechanism and motor using the same

Technical Field

The present disclosure relates to a mounting mechanism for mounting a rotating body to a rotating shaft and a motor mounted with an encoder using the mounting mechanism. The motor has an encoder mounted using a mounting mechanism.

Background

Conventionally, there is a motor in which a rotary encoder is mounted. The rotary encoder includes a sleeve (ボス), a light emitting diode as a light source, a substrate on which a position detection pattern is formed, and a rotating plate which is attached to the sleeve and has a light transmitting window through which light from the light emitting diode passes.

The sleeve is fastened to a rotating shaft of the motor by a screw or the like, and is attached to the rotating shaft.

The rotating plate is positioned between the light emitting diode and the substrate. The rotating plate rotates together with the rotating shaft.

When the rotating plate rotates, light emitted from the light emitting diode reaches the position detection pattern through a light transmission window formed in the rotating plate (see, for example, patent documents 1 and 2).

The sleeve is fastened to the rotary shaft by fastening the sleeve from the outer peripheral side surface of the sleeve with a screw or the like. In this case, the fastening of the screw may cause a deviation between the rotation center of the sleeve and the rotation center of the rotary shaft. Due to the deviation, the rotary encoder causes a radial runout of the rotary plate with respect to the rotation center of the rotary encoder, i.e., the rotation center of the rotary shaft. When a radial run-out occurs in the rotating plate, the following problems occur: the detection accuracy of the position detection pattern provided on the rotary plate is lowered, and the desired control by the rotary encoder cannot be performed. In the following description, the rotation center is also referred to as the axial center.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. H08-168210

Patent document 2: japanese patent laid-open No. 2008-228397

Disclosure of Invention

The purpose of the present disclosure is to suppress radial runout of a rotating body when a device having the rotating body such as a rotating plate is mounted on a shaft such as a rotating shaft.

The present disclosure is directed to a mounting mechanism for mounting a rotary body to a rotary shaft and a motor having a rotary encoder mounted using the mounting mechanism, and the following solutions are adopted.

That is, one aspect of the present disclosure is an attachment mechanism for attaching a rotating body to a rotating shaft. The mounting mechanism comprises a 1 st nut, a 2 nd nut and an annular body.

The 1 st nut includes a cylindrical portion and a flange portion. The rotation shaft penetrates the cylindrical portion. The cylindrical portion extends along the axial center of the rotating shaft and has a 1 st outer peripheral surface including a 1 st thread. The flange portion projects in a direction intersecting the axial center and in a direction opposite to the side where the rotary shaft is located, and has a 1 st inner peripheral surface including a 1 st thread groove.

The rotation shaft penetrates the 2 nd nut. The 2 nd nut includes a 2 nd thread groove and a small hole portion. The 2 nd thread groove is formed in a part of the 2 nd inner peripheral surface facing the rotation shaft, and is screw-coupled with the 1 st thread ridge. The small hole is formed in the 2 nd inner circumferential surface at a portion other than the 2 nd thread groove, and is fitted to the rotary shaft.

The rotating shaft penetrates the annular body, and the annular body is positioned between the rotating shaft and the 3 rd inner circumferential surface of the cylindrical portion. The ring body has a 1 st inclined surface, and when the 1 st nut and the 2 nd nut are screwed in a direction in which they approach each other, the 1 st inclined surface converts a force acting in a direction along the axis, which is applied from the 1 st nut and the 2 nd nut, into a force acting in a direction intersecting the axis.

Another aspect of the present disclosure is a motor including: a rotor having a rotor core attached to a rotating shaft; a bearing for rotatably supporting the rotary shaft; and a stator located opposite to the rotor, the encoder being mounted to the rotary shaft using the mounting mechanism of the present disclosure.

According to the present disclosure, when a device having a rotating body such as a rotating plate is attached to a rotating shaft, radial runout of the rotating body can be suppressed.

Drawings

Fig. 1 is a cross-sectional view showing an outline of a motor using the mounting mechanism according to embodiment 1 of the present disclosure.

Fig. 2 is an exploded perspective view showing the mounting mechanism and the encoder mounted by the mounting mechanism according to embodiment 1 of the present disclosure.

Fig. 3 is a cross-sectional view showing the mounting mechanism and the encoder mounted by the mounting mechanism according to embodiment 1 of the present disclosure.

Fig. 4 is a schematic cross-sectional view showing an action on the rotary shaft at the mounting mechanism according to embodiment 1 of the present disclosure.

Fig. 5 is a perspective view of one member constituting the mounting mechanism according to embodiment 1 of the present disclosure.

Fig. 6 is a front view of one member constituting the mounting mechanism of embodiment 1 of the present disclosure.

Fig. 7 is a front view of another member constituting the mounting mechanism of embodiment 1 of the present disclosure.

Fig. 8 is a perspective view of another member constituting the mounting mechanism of embodiment 1 of the present disclosure.

Fig. 9 is a schematic cross-sectional view showing an action on the rotary shaft at the mounting mechanism according to embodiment 2 of the present disclosure.

Fig. 10 is a perspective view of one member constituting the mounting mechanism according to embodiment 2 of the present disclosure.

Fig. 11 is a front view of one member constituting the mounting mechanism of embodiment 2 of the present disclosure.

Fig. 12 is a front view of another member constituting the mounting mechanism of embodiment 2 of the present disclosure.

Fig. 13 is a perspective view of another member constituting the mounting mechanism of embodiment 2 of the present disclosure.

Fig. 14 is a schematic cross-sectional view showing an action on the rotary shaft at the mounting mechanism according to embodiment 3 of the present disclosure.

Fig. 15 is a perspective view of one member constituting the mounting mechanism according to embodiment 3 of the present disclosure.

Fig. 16 is a front view of one member constituting the mounting mechanism of embodiment 3 of the present disclosure.

Fig. 17 is a front view of another member constituting the mounting mechanism of embodiment 3 of the present disclosure.

Fig. 18 is a perspective view of another member constituting the mounting mechanism according to embodiment 3 of the present disclosure.

Fig. 19 is a schematic cross-sectional view showing an action on the rotary shaft at the mounting mechanism according to embodiment 4 of the present disclosure.

Fig. 20 is a perspective view of one member constituting the mounting mechanism according to embodiment 4 of the present disclosure.

Fig. 21 is a front view of one member constituting the mounting mechanism of embodiment 4 of the present disclosure.

Fig. 22 is a front view of another member constituting the mounting mechanism of embodiment 4 of the present disclosure.

Fig. 23 is a perspective view of another member constituting the mounting mechanism according to embodiment 4 of the present disclosure.

Fig. 24 is a front view of one member constituting the mounting mechanism of embodiment 5 of the present disclosure.

Fig. 25 is a front view of another member constituting the mounting mechanism of embodiment 5 of the present disclosure.

Detailed Description

(pass through to complete the disclosure)

Conventionally, motors capable of performing position control, speed control, and the like have been used as power sources for conveying various components and products or for moving an X-Y table. In the motor as described above, an optical or magnetic rotary encoder (hereinafter also simply referred to as an encoder) is generally mounted as a member for detecting the rotation speed and the rotation angle of the rotating shaft.

The rotating plate is formed with a pattern for position detection. An encoder is attached to the rotating shaft. Accordingly, in order to improve the position detection accuracy of the encoder, it is important to accurately position the rotation center of the rotating plate with respect to the rotation center of the rotating shaft.

The rotating plate is attached to and held by a boss as a reinforcing component for reinforcing the cylindrical shaft body. The shaft sleeve provided with the rotating plate is provided with a shaft hole. A rotary shaft to which the encoder is attached is inserted into the shaft hole. The shaft sleeve is fixed on the rotating shaft. Specifically, for example, a small screw is fastened from the outer peripheral side surface of the sleeve to fix the sleeve to the rotary shaft.

In the encoder configured as described above, first, the mounting accuracy of the rotary plate to the boss depends on the positioning accuracy between the rotation center of the rotary shaft and the rotation center of the boss. Therefore, if a gap is formed between the shaft hole of the sleeve and the rotating shaft of the motor, a deviation occurs between the rotation center of the rotating shaft and the rotation center of the sleeve. Therefore, it is difficult to improve the mounting accuracy of the rotary plate to the boss. Therefore, it is difficult to suppress radial runout of the rotating plate rotating together with the rotating shaft.

The mounting accuracy of the sleeve with respect to the rotation shaft also depends on the positioning accuracy between the rotation center of the rotation shaft and the rotation center of the sleeve. Therefore, if a gap exists between the shaft hole of the sleeve and the rotating shaft, the rotation center of the sleeve and the rotation center of the rotating shaft are deviated by fastening the small screw. Therefore, it is difficult to improve the mounting accuracy of the sleeve with respect to the rotary shaft. Therefore, in this case as well, it is difficult to suppress radial runout of the rotary plate with respect to the rotary shaft.

The present disclosure has been made in view of the above-described problems. Hereinafter, the embodiments will be described in detail with reference to the drawings as appropriate. However, the detailed description thereof may be omitted. For example, detailed descriptions of known matters and repetitive descriptions of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy of the following description, which will be readily understood by those skilled in the art.

In addition, the drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and thus are not intended to limit the subject matter recited in the claims.

(embodiment mode 1)

Embodiments of the present disclosure are explained with reference to the drawings.

Fig. 1 is a cross-sectional view showing an outline of a motor 200 using the mounting mechanism according to embodiment 1 of the present disclosure.

(outline of Motor)

The embodiment of the present disclosure will be described by exemplifying a form in which the encoder is attached to the motor by the attachment mechanism. The attachment mechanism of the present disclosure may be used for devices other than motors as long as the rotating body can be attached to the rotating shaft.

As shown in fig. 1, a motor 200 as an embodiment of the present disclosure includes a rotor 210, a bearing 220, and a stator 230.

Rotor 210 has rotor core 212 attached to rotating shaft 110. In the present embodiment, rotor core 212 is formed by stacking thin steel plates in the axial center C direction of rotary shaft 110. The laminated rotor core 212 has a plurality of magnet holes 214 formed along the axial center C of the rotating shaft 110. Permanent magnets 216 are inserted into the magnet holes 214, respectively.

The bearing 220 rotatably supports the rotary shaft 110. In the present embodiment, the pair of bearings 220 are provided so as to sandwich the rotor core 212. The pair of bearings 220 are held by a case 222 constituting a housing of the motor 200.

Stator 230 is located opposite rotor 210. In the present embodiment, stator 230 includes stator core 232 and windings 234. Stator core 232 is formed by laminating thin steel plates along axial center C of rotary shaft 110. The laminated stator core 232 has a plurality of teeth protruding toward the axial center C. Grooves are formed between adjacent teeth of the plurality of teeth, respectively. The winding 234 is wound around the stator core 232 by slots. The winding 234 is wound around the stator core 232 via an insulator 236 that is an insulator.

The encoder 100 is mounted on the rotary shaft 110 using the mounting mechanism 40.

The mounting mechanism 40 includes a boss fixing nut 10 as a 1 st nut, a lock nut 20 as a 2 nd nut, and a tapered ring 30 as an annular body.

The encoder 100 includes an LED (Light Emitting Diode) element 151 as a Light Emitting element, a Phototransistor (photo transistor)152 as a Light receiving element, and a boss body (ボス body) 120 for fixing the rotating plate 130 to the rotating shaft 110. The rotating plate 130 is formed with a light transmitting window through which light emitted from the LED element 151 passes.

The details of the mounting mechanism 40 and the encoder 100 will be described later.

In the present configuration, a drive current is supplied to the winding 234 from the outside of the motor 200. The winding 234 supplied with the driving current generates a predetermined magnetic flux via the stator core 232. The permanent magnet 216 embedded in the rotor core 212 receives the influence of the magnetic flux generated in the stator core 232. The rotor 210 rotates about the rotation axis 110 by the influence of the magnetic flux received by the permanent magnet 216.

The rotating plate 130 mounted to the rotating shaft 110 using the mounting mechanism 40 rotates together with the rotor 210.

The LED element 151 constituting the encoder 100 emits light. The phototransistor 152 receives light emitted from the LED element 151. Since the rotating plate 130 rotates, light emitted from the LED element 151 is received by the phototransistor 152 only when the light transmission window formed in the rotating plate 130 passes between the LED element 151 and the phototransistor 152. At other times, the light emitted from the LED element 151 is blocked by the rotating plate 130, and thus the phototransistor 152 cannot receive the light emitted from the LED element 151.

The phototransistor 152 receives light emitted from the LED element 151, so that the encoder 100 can detect a state in which the rotor 210 is rotating. The control unit of motor 200 receives the detected rotation state of rotor 210 and controls the drive current to be supplied to windings 234.

As will be described later, the encoder 100 of the present embodiment can be attached so that the axial center J of the shaft housing body 120 is positioned on the axial center C of the rotating shaft 110. This can suppress the occurrence of a misalignment between the rotation center of the rotary shaft 110 and the rotation center of the boss body 120. Therefore, the encoder 100 can accurately detect the rotation state of the rotor 210.

In the above description, a brushless motor having a magnet-embedded rotor is exemplified as the motor 200. The motor of the present disclosure can be used in other types of brushless motors, commutator motors, induction motors, and the like. The motor of the present disclosure can be used for both an inner rotor type motor and an outer rotor type motor.

(Structure of encoder)

Fig. 2 is an exploded perspective view showing the mounting mechanism 40 and the encoder 100 mounted by the mounting mechanism 40 according to embodiment 1 of the present disclosure. Fig. 3 is a cross-sectional view showing the mounting mechanism 40 and the encoder 100 mounted on the mounting mechanism 40 according to embodiment 1 of the present disclosure.

As shown in fig. 2 and 3, the rotary body of the present embodiment is an encoder 100 including a shaft housing 120 and a rotary plate 130.

The rotating shaft 110 penetrates the shaft housing 120. The boss body 120 extends along the axial center C of the rotating shaft 110. The boss body 120 has a 2 nd outer peripheral surface 124, and the 2 nd outer peripheral surface 124 includes a 2 nd screw thread 122 screwed with the 1 st screw groove 18 included in the flange portion 10B.

The rotating plate 130 is mounted so as to intersect the axis C. Specifically, the rotating plate 130 is formed to extend in a plane direction having the axis C as a normal line.

This is explained in further detail using the drawings.

As shown in fig. 2 and 3, for example, the encoder 100 is attached to an end of the rotary shaft 110 by the attachment mechanism 40 of the present embodiment. Here, the rotation shaft 110 is a shaft of the motor. The mounting mechanism 40 of the present disclosure can be used for a shaft body having a similar function, in addition to the shaft of the motor.

The encoder 100 has a boss body 120 as a rotating body fitted to the rotating shaft 110 and held by the mounting mechanism 40. A rotating plate 130 for detecting a rotational position or a rotational speed is held on the protrusion 120a of the boss body 120 so as to be orthogonal to the axial center J of the boss body 120. The rotating plate 130 is fixed to the boss body 120 by screws, fitting, or adhesive. A light transmitting window 131, which is a transmissive pattern for position detection, is formed in the rotating plate 130 to selectively transmit light. The light-transmitting window 131 can be made of, for example, a transparent glass material or a resin material.

As shown in fig. 3, the encoder 100 is an optical detector in which, for example, an LED element 151 as a light emitting element and a phototransistor 152 as a light receiving element are disposed in a casing 100 a. The housing 100a is formed of a metal plate material, for example, and is attached so as to surround the encoder 100.

The light emitting element may be, for example, an LED element 151. The light-emitting element may have the same function, and other elements may be used. The light receiving element may be, for example, a phototransistor 152. The light receiving element may have the same function, and other elements may be used. The LED element 151 and the phototransistor 152 are disposed in the case 100a at positions facing each other with the rotating plate 130 interposed therebetween. Thus, the transmitted light emitted from the LED element 151 and transmitted through the rotating plate 130 is received by the phototransistor 152 and electrically detected. In addition, a circuit board on which a control circuit for controlling the LED element 151 and the phototransistor 152 is mounted may be disposed inside the housing 100 a.

The boss body 120 held by the rotating shaft 110 and the housing 100a are supported via a bearing mechanism 140, and the boss body 120 is rotatable about the shaft center J as a rotation center. The case 100a may be held by an external member not shown via a leaf spring or the like, for example.

(Structure of mounting mechanism)

Fig. 4 is a schematic cross-sectional view showing an action on the rotating shaft 110 at the mounting mechanism 40 in embodiment 1 of the present disclosure. Fig. 5 is a perspective view of one member constituting mounting mechanism 40 according to embodiment 1 of the present disclosure. Fig. 6 is a front view of one member constituting the mounting mechanism 40 according to embodiment 1 of the present disclosure. Fig. 7 is a front view of another member constituting mounting mechanism 40 according to embodiment 1 of the present disclosure. Fig. 8 is a perspective view of another member constituting the mounting mechanism 40 according to embodiment 1 of the present disclosure.

As shown in fig. 2 to 4, the mounting mechanism 40 of the present embodiment is configured by 3 annular members through which the rotary shaft 110 penetrates.

That is, the attachment mechanism 40 of the present embodiment is used to attach the boss body 120 as a rotating body to the rotating shaft 110.

The rotation shaft 110 penetrates the sleeve fixing nut 10. The sleeve fixing nut 10 includes a cylindrical portion 10A and a flange portion 10B.

The cylindrical portion 10A extends along the axial center C of the rotating shaft 110, and has a 1 st outer peripheral surface 12 including a 1 st thread 14. The flange portion 10B projects in a direction intersecting the axial center C and in a direction opposite to the rotation shaft 110, and has a 1 st inner peripheral surface 16 including a 1 st thread groove 18. The 1 st inner circumferential surface 16 of the flange portion 10B is located at a position facing the rotary shaft 110.

The rotation shaft 110 penetrates the lock nut 20. The lock nut 20 includes a 2 nd thread groove 22 and an eyelet portion 24.

The 2 nd thread groove 22 is formed in a part of the 2 nd inner peripheral surface 26 facing the rotation shaft 110, and is screwed with the 1 st thread ridge 14 of the sleeve fixing nut 10 as the 1 st nut. The small hole 24 is formed in the 2 nd inner circumferential surface 26 at a portion other than the 2 nd thread groove 22, and is fitted to the rotary shaft 110.

The rotary shaft 110 penetrates the conical ring 30 as an annular body. The taper ring 30 is located between the 3 rd inner circumferential surface 17 of the cylindrical portion 10A and the rotary shaft 110. The taper ring 30 has an inclined surface 32, and when the boss fixing nut 10 as the 1 st nut and the locknut 20 as the 2 nd nut are screwed together in a direction (D1, D2 in fig. 4) to approach each other, the inclined surface 32 converts forces F01, F02 acting in a direction along the axial center C, which are applied from the boss fixing nut 10 as the 1 st nut and the locknut 20 as the 2 nd nut, respectively, into forces F1, F2 acting in a direction intersecting the axial center C.

In particular, the following forms have the following remarkable operational effects.

The annular body for mounting mechanism 40 is a pair of tapered rings 30 having

inclined surfaces

32a, 32b that abut against each other oppositely. The taper ring 30 is an example of an annular body such as a wedge ring, and includes an outer ring 30a and an inner ring 30 b.

In the present embodiment, the inclined surface 32 is composed of a 1 st inclined surface and a 2 nd inclined surface that is in contact with the 1 st inclined surface in an opposed manner. In the following description, the inclined surface 32a of the outer ring 30a functions as the 1 st inclined surface. On the other hand, the inclined surface 32b of the inner ring 30b functions as the 2 nd inclined surface.

This is explained in further detail using the drawings.

As shown in fig. 3 and 4, the sleeve fixing nut 10 includes a flange portion 10B and a cylindrical portion 10A. A 1 st thread groove 18 is formed in a 1 st inner peripheral surface 16 of the flange portion 10B facing the boss body 120. The cylindrical portion 10A has a 1 st outer peripheral surface 12 on the opposite side of the boss body 120. The 1 st thread ridge 14 is formed on the 1 st outer circumferential surface 12.

A 2 nd thread 122 is formed on an end portion 120b of the boss body 120 on the opposite side to the protrusion 120a formed on the boss body 120 in the axial center J direction. The 2 nd thread ridge 122 is screw-coupled to the 1 st thread groove 18 formed in the sleeve fixing nut 10.

The lock nut 20 fixedly holds the sleeve fixing nut 10 to the sleeve body 120. A 2 nd thread groove 22 to be screwed with the 1 st thread 14 formed in the sleeve fixing nut 10 is formed in a part of the 2 nd inner peripheral surface 26 of the lock nut 20. The lock nut 20 has a small hole portion 24 to be fitted to the rotary shaft 110 at least in a part of the remaining portion of the 2 nd inner peripheral surface 26 of the lock nut 20.

Here, the cylindrical portion 10A of the sleeve fixing nut 10 is formed so as to form a gap portion 10C with the rotary shaft 110. A pair of tapered rings 30 are inserted into the space 10C. The pair of tapered rings 30 includes an outer ring 30a and an inner ring 30b, and the outer ring 30a and the inner ring 30b have inclined

surfaces

32a and 32b that are in contact with each other in an opposing manner. When the lock nut 20 is screwed in the direction D2 of the sleeve fixing nut 10, the inclined surfaces 32a of the outer rings 30a of the pair of tapered rings 30 slide out to the outside of the inclined surfaces 32b of the inner rings 30 b. In other words, the inclined surface 32b of the inner ring 30b of the pair of tapered rings 30 is bored inward of the inclined surface 32a of the outer ring 30 a. This increases the thickness of the taper ring 30 in the direction intersecting the axial center C, and therefore the outer diameter of the taper ring 30 increases. As a result, as shown in fig. 4, the tapered ring 30 having an enlarged outer diameter generates a force F1 acting outward in a direction intersecting the axial center C with respect to the sleeve fixing nut 10 and the lock nut 20. Thus, a reaction force F2 of the force F1 is generated in the sleeve body 120. As a result, the boss body 120 is strongly pressed toward the axial center C from all around the boss fixing nut 10 and the lock nut 20 in the direction intersecting the axial center C. That is, the shaft center J (rotation center) of the sleeve fixing nut 10, the lock nut 20, and the tapered ring 30 coincides with the shaft center C (rotation center) of the sleeve body 120. Therefore, the boss body 120 and the rotary plate 130, which are rotating bodies, can be prevented from radially jumping.

Further, the outer ring 30a and the inner ring 30b constituting the tapered ring 30 preferably have a large friction coefficient at the

inclined surfaces

32a and 32b, which are contact surfaces (sliding surfaces) therebetween.

As shown in fig. 4, the end surface 34 of the tapered ring 30 on the sleeve fixing nut 10 side preferably abuts against the end surface 120c of the sleeve body 120 on the sleeve fixing nut 10 side. Alternatively, the end surface 34 of the collar fixing nut 10 side of the taper ring 30 may abut against the inner surface 10d of the flange portion 10B of the collar fixing nut 10.

Further, it is preferable that an end surface 34a of the taper ring 30 on the small hole portion 24 side of the lock nut 20 abuts against the inner surface 20a of the small hole portion 24.

With this configuration, the force F1 as an acting force and the force F2 as a reaction force can be reliably generated.

The following configuration can further provide a significant operational effect.

As shown in fig. 5, it is preferable that the inner ring 30b, which is a tapered ring located on the side of the rotation shaft 110 out of the pair of tapered rings 30 used in the mounting mechanism 40, has a slit 36 formed so that the extended line thereof intersects with the shaft center C. In other words, the inner ring 30b has the slit 36. The extension line of the slit 36 intersects the axis C. Here, the extension line of the slit 36 is a line obtained by extending the slit 36, which is a narrow slit gap, in the cutting direction.

Alternatively, as shown in fig. 6 and 7, it is preferable that the inner ring 30b, which is the tapered ring located on the side of the rotation shaft 110 out of the pair of tapered rings 30 used in the mounting mechanism 40, has a plurality of slits 36 formed so that the extended line thereof intersects with the shaft center C. In other words, the inner ring 30b has a plurality of slits 36. The extension lines of the slits 36 intersect the axis C. In a plane orthogonal to the axis C, the plurality of slits 36 are preferably located at positions spaced apart in the circumferential direction around the axis C.

The slit 36 is formed along the inclined surface 32. When the center line of the slit 36 is extended, the extended line preferably intersects the axis C.

In other words, on a plane orthogonal to the axial center C, the plurality of slits 36 are preferably located on the circumference at appropriate angles in the radial direction around the axial center C.

As a particularly preferable example, as shown in fig. 6, the slits 36 are preferably located at every θ 1 of 120 °. Alternatively, as shown in fig. 7, the slits 36 are preferably located every θ 2 equal to 90 °.

In the specific example shown in fig. 6 and 7, the slits 36 are provided at equal intervals. The equal intervals or the appropriate angles are not intended to be mathematically equal, as long as the holding forces applied to the rotary shaft 110 by the inclined surfaces 32b separated by the slits 36 are equal. Typically, the unevenness due to the manufacturing tolerance is within the range of the equal interval or the appropriate angle in the present embodiment.

In this configuration, the inner ring 30b can press the boss body 120 more strongly from the periphery of the boss fixing nut 10 and the lock nut 20 toward the axial center C in all directions in the direction intersecting the axial center C. That is, the strength with which the inner ring 30b fastens the boss body 120 can be adjusted within a range that can be adjusted by the width dimension of the slit 36. Therefore, the accuracy is improved in which the axial centers J (rotational centers) of the sleeve fixing nut 10, the lock nut 20, and the tapered ring 30 are all aligned with the axial center C (rotational center) of the sleeve body 120. Therefore, the radial runout of the boss body 120 and the rotary plate 130 as the rotary bodies can be further suppressed.

In particular, when 3 slits 36 are formed as shown in fig. 6 and 4 slits 36 are formed as shown in fig. 7, a proper holding force is applied to the rotary shaft 110 from the inclined surface 32b divided by the slits. The man-hour for forming the slit 36 on the inclined surface 32b can be realized within a range of an appropriate man-hour.

As shown in FIG. 8, the slit width W2 on the opening 36c side of the slit 36a for the mounting mechanism 40 is preferably wider than the slit width W1 on the tip 36b side. In other words, the slit 36a of the inner ring 30b of the tapered ring on the rotation axis 110 side has a slit width W2 on the opening 36c side of the tapered ring that is wider than the slit width W1 on the tip 36b side of the tapered ring.

In the case of this configuration, even if a gap is generated between the inner peripheral surface of the inner ring 30b and the outer peripheral surface of the rotary shaft 110 due to some cause, the gap can be absorbed by the difference between the slit width W2 and the slit width W1. That is, the inner ring 30b and the rotary shaft 110 can always secure an appropriate holding force by the difference between the slit width W2 and the slit width W1.

As described above, the attachment mechanism 40 of the present embodiment is an attachment mechanism 40 for attaching a rotating body corresponding to the boss body 120 to the rotating shaft 110, and includes the 1 st nut 10, the 2 nd nut 20, and the annular body 30.

The 1 st nut 10 includes a cylindrical portion 10A and a flange portion 10B. The rotation shaft 110 penetrates the cylindrical portion 10A. The cylindrical portion 10A extends along the axial center C of the rotating shaft 110, and has a 1 st outer peripheral surface 12 including a 1 st thread 14. The flange portion 10B projects in a direction intersecting the axial center C and in a direction opposite to the rotation shaft 110, and has a 1 st inner peripheral surface 16 including a 1 st thread groove 18.

The rotation shaft 110 penetrates the 2 nd nut 20. The 2 nd nut 20 includes a 2 nd thread groove 22 and a small hole portion 24. The 2 nd thread groove 22 is formed in a part of the 2 nd inner circumferential surface 26 facing the rotation shaft 110, and is screw-coupled with the 1 st thread ridge 14. The small hole 24 is formed in the 2 nd inner circumferential surface 26 at a portion other than the 2 nd thread groove 22, and is fitted to the rotary shaft 110.

The rotating shaft 110 penetrates the annular body 30, and the annular body 30 is located between the rotating shaft 110 and the 3 rd inner circumferential surface 17 of the cylindrical portion 10A. The ring body 30 has a 1 st inclined surface corresponding to the inclined surface 32a, and when the 1 st nut 10 and the 2 nd nut 20 are screwed together in a direction of approaching each other, the inclined surface 32a converts a force acting in a direction along the axis C, which is applied from the 1 st nut 10 and the 2 nd nut 20, respectively, into a force acting in a direction intersecting the axis C.

This can suppress the radial runout of the rotating body corresponding to the boss body 120.

The ring body 30 may be a pair of tapered rings 30 further having a 2 nd inclined surface corresponding to the inclined surface 32b which is in contact with a 1 st inclined surface corresponding to the inclined surface 32 a.

Further, of the pair of tapered rings 30, the tapered ring corresponding to the inner ring 30b located on the rotation shaft 110 side has the slit 36. The extension line of the slit 36 preferably intersects the axis C.

Of the pair of tapered rings 30, the tapered ring corresponding to the inner ring 30b located on the rotation shaft 110 side has a plurality of slits 36. The extension lines of the slits 36 intersect the axis C. In a plane orthogonal to the axis C, the plurality of slits 36 are preferably located at positions spaced apart in the circumferential direction around the axis C.

Further, it is preferable that the slit 36a of the taper ring corresponding to the inner ring 30b on the side of the rotation shaft 110 has a slit width W2 on the side of the opening 36c of the taper ring corresponding to the inner ring 30b wider than a slit width W1 on the side of the tip 36b of the taper ring corresponding to the inner ring 30 b.

In addition, the mounting mechanism 40 may be an encoder 100 including a boss body 120 and a rotary plate 130. The rotating shaft 110 penetrates the shaft housing 120. Preferably, the sleeve body 120 extends along the axial center C of the rotating shaft 110, and has a 2 nd outer peripheral surface 124, and the 2 nd outer peripheral surface 124 includes a 2 nd thread ridge 122 screwed with the 1 st thread groove 18 included in the flange portion 10B. The rotating plate 130 is preferably installed to intersect the axis C.

Further, the motor 200 of the present embodiment includes: a rotor 210 having a rotor core 212 attached to the rotary shaft 110; a bearing 220 for rotatably supporting the rotary shaft 110; and a stator 230 located opposite to the rotor 210. The encoder 100 is mounted to the rotating shaft 110 using the illustrated mounting mechanism 40.

(embodiment mode 2)

The structure of the mounting mechanism 440 of embodiment 2 will be described.

Fig. 9 is a schematic cross-sectional view showing an action on the rotating shaft 110 at the mounting mechanism 440 according to embodiment 2 of the present disclosure. Fig. 10 is a perspective view of one member constituting the mounting mechanism 440 according to embodiment 2 of the present disclosure. Fig. 11 is a front view of one member constituting the mounting mechanism 440 of embodiment 2 of the present disclosure. Fig. 12 is a front view of another member constituting the mounting mechanism 440 of embodiment 2 of the present disclosure. Fig. 13 is a perspective view of another member constituting the mounting mechanism 440 according to embodiment 2 of the present disclosure.

In describing the attachment mechanism 440, the same components as those in embodiment 1 are denoted by the same reference numerals as in embodiment 1, and the description thereof will be given with reference to these components.

As shown in fig. 9, a shaft housing 460, which is a rotating body capable of using the mounting mechanism 440, has a tapered portion 462 extending in a direction along the axial center C between the 3 rd inner peripheral surface 17 and the rotating shaft 110. The tapered portion 462 includes an inclined surface 432b opposed to the inclined surface 432a of the tapered ring 430 as an annular body.

In the following description, the inclined surface 432a of the taper ring 430 functions as the 1 st inclined surface. On the other hand, the inclined surface 432b of the tapered portion 462 functions as the 2 nd inclined surface.

This is explained in further detail using the drawings.

As shown in fig. 9, the sleeve fixing nut 10 includes a flange portion 10B and a cylindrical portion 10A. A 1 st thread groove 18 is formed in a 1 st inner peripheral surface 16 of the flange portion 10B facing the boss body 460. The cylindrical portion 10A has a 1 st outer peripheral surface 12 on the side opposite to the side where the boss body 460 is located. The 1 st thread ridge 14 is formed on the 1 st outer circumferential surface 12.

In the axial center J direction, the 2 nd thread ridge 122 is formed at an end portion 460b of the boss body 460 on the opposite side of the projection formed on the boss body 460. The 2 nd thread ridge 122 is screw-coupled to the 1 st thread groove 18 formed in the sleeve fixing nut 10.

The lock nut 20 fixedly holds the sleeve fixing nut 10 to the sleeve body 460. A 2 nd thread groove 22 to be screwed with the 1 st thread 14 formed in the sleeve fixing nut 10 is formed in a part of the 2 nd inner peripheral surface 26 of the lock nut 20. The lock nut 20 has a small hole portion 24 to be fitted to the rotary shaft 110 at least in a part of the remaining portion of the 2 nd inner peripheral surface 26 of the lock nut 20.

Here, the cylindrical portion 10A of the sleeve fixing nut 10 is formed so as to form a gap 410C between the cylindrical portion and the tapered portion 462. The tapered ring 430 is inserted into the space 410C. The tapered ring 430 has an inclined surface 432a that abuts against an inclined surface 432b of the tapered portion 462. When the lock nut 20 is screwed in the direction D2 of the sleeve fixing nut 10, the inclined surface 432a of the tapered ring 430 slides out to the outside of the inclined surface 432b of the tapered portion 462. In other words, the inclined surface 432b of the tapered portion 462 is bored inward of the inclined surface 432a of the tapered ring 430 with respect to the tapered portion 462. Thereby, the taper ring 430 moves in a direction away from the axial center C of the rotary shaft 110 in a direction intersecting the axial center C, and the outer diameter of the taper ring 430 is enlarged. As a result, as shown in fig. 9, the tapered ring 430 having an enlarged outer diameter generates a force F1 acting outward in a direction intersecting the axial center C with respect to the sleeve fixing nut 10 and the lock nut 20. Thus, a reaction to the force F1, i.e., force F2, is created in the bushing body 460. As a result, the boss body 460 is strongly pressed toward the axial center C from all around the boss fixing nut 10 and the lock nut 20 in the direction intersecting the axial center C. That is, the shaft center J (rotation center) of the sleeve fixing nut 10, the lock nut 20, and the tapered ring 430 coincides with the shaft center C (rotation center) of the sleeve body 460. Therefore, the boss body 460 as a rotating body and the radial runout of the rotating plate 130 can be suppressed.

Further, it is preferable that the friction coefficient at the contact surface (sliding surface) where the inclined surface 432a of the tapered ring 430 and the inclined surface 432b of the tapered portion 462 are in contact is large.

As shown in fig. 10, the shaft housing 460 preferably has a tapered portion 462 having a slit 436 formed such that an extension thereof intersects the shaft center C. In other words, the tapered portion 462 has the slit 436. Here, the extension line of the slit 436 is a line obtained by extending the slit 436, which is a narrow slit gap, in the cutting direction.

Alternatively, as shown in fig. 11 and 12, the boss body 460 preferably has a tapered portion 462 having a plurality of slits 436 formed such that the extension line thereof intersects the shaft center C. In other words, the tapered portion 462 has a plurality of slits 436. The respective extension lines of the plurality of slits 436 intersect the shaft center C. In a plane orthogonal to the axis C, the plurality of slits 436 are preferably located at positions spaced apart from each other in the circumferential direction around the axis C.

The slit 436 is formed along the inclined surface 432 b. When the center line of the slit 436 is extended, the extended line preferably intersects the axis C.

In other words, on a plane orthogonal to the axis C, the plurality of slits 436 are preferably located on the circumference at appropriate angles in the radial direction around the axis C.

As a particularly preferable example, as shown in fig. 11, the slits 436 are preferably located at every θ 1 of 120 °. Alternatively, as shown in fig. 12, each slit 436 is preferably located at every θ 2 equal to 90 °.

In the specific example shown in fig. 11 and 12, the slits 436 are provided at equal intervals. The equal interval or the appropriate angle is sufficient if the holding force applied to the rotation shaft 110 by the inclined surfaces 432b separated by the slits 436 is equal, and is not intended to be mathematically equal. Typically, the unevenness due to the manufacturing tolerance is within the range of the equal interval or the appropriate angle in the present embodiment.

In this configuration, the tapered portion 462 can press the boss body 460 more strongly toward the axial center C from all around the boss fixing nut 10 and the lock nut 20 in a direction intersecting the axial center C. That is, the tapered portion 462 can adjust the strength of fastening the boss body 460 within a range that can be adjusted by the width dimension of the slit 436. Therefore, the accuracy is improved in which the axial centers J (rotational centers) of the sleeve fixing nut 10, the lock nut 20, and the tapered ring 430 are all aligned with the axial center C (rotational center) of the sleeve body 460. Therefore, the radial runout of the boss body 460 and the rotary plate 130 as the rotary bodies can be further suppressed.

In particular, when 3 slits 436 are formed as shown in fig. 11 and 4 slits 436 are formed as shown in fig. 12, a proper holding force is applied to the rotary shaft 110 from the inclined surface 432b divided by the slits. The man-hour for forming the slit 436 on the inclined surface 432b can be realized within a range of an appropriate man-hour.

As shown in fig. 13, the slit width W2 on the opening 436c side of the slit 436a is preferably wider than the slit width W1 on the tip 436b side. In other words, the slit 436a of the tapered portion 462 has a slit width W2 on the opening 36c side of the tapered portion 462 wider than a slit width W1 on the tip 436b side of the tapered portion 462.

In the case of this configuration, even if a gap is generated between the inner peripheral surface of the tapered portion 462 and the outer peripheral surface of the rotary shaft 110 due to some cause, the gap can be absorbed by the difference between the slit width W2 and the slit width W1. That is, the tapered portion 462 and the rotary shaft 110 can always secure an appropriate holding force by the difference between the slit width W2 and the slit width W1.

As is clear from the above description, in embodiment 2 described above, the sleeve body 460 has the tapered portion 462 reaching between the 3 rd inner peripheral surface 17 of the sleeve fixing nut 10 and the outer peripheral surface of the rotary shaft 110. The tapered portion 462 functions as the inner ring 30b described in embodiment 1. In this configuration, the taper ring 430 functions as the outer ring 30a described in embodiment 1. That is, in embodiment 2, the tapered ring 430 can be formed by one member as compared with embodiment 1. Thus, embodiment 2 is improved in assembling workability as compared with the mounting mechanism 40 shown in embodiment 1.

As described above, the rotating body corresponding to the shaft housing 460 of the present embodiment has the tapered portion 462 extending between the 3 rd inner peripheral surface 17 and the rotating shaft 110 in the direction along the shaft center C. The tapered portion 462 includes a 2 nd inclined surface corresponding to the inclined surface 432b, and the 2 nd inclined surface faces the 1 st inclined surface corresponding to the inclined surface 432 a.

This can suppress the radial runout of the rotating body corresponding to the boss body 460.

In addition, the tapered portion 462 has a slit 436. The extension line of the slit 436 preferably intersects the axis C.

In addition, the tapered portion 462 has a plurality of slits 436. The respective extension lines of the plurality of slits 436 intersect the shaft center C. In a plane orthogonal to the axis C, the plurality of slits 436 are preferably located at positions spaced apart from each other in the circumferential direction around the axis C.

In addition, it is preferable that the slit 436a of the tapered portion 462 has a slit width W2 on the opening 436c side of the tapered portion 462 wider than a slit width W1 on the tip 436b side of the tapered portion 462.

(embodiment mode 3)

The structure of the mounting mechanism 540 according to embodiment 3 will be described.

Fig. 14 is a schematic cross-sectional view showing an action on the rotating shaft 110 at the attachment mechanism 540 according to embodiment 3 of the present disclosure. Fig. 15 is a perspective view of one member constituting the attachment mechanism 540 according to embodiment 3 of the present disclosure. Fig. 16 is a front view of one member constituting the mounting mechanism 540 according to embodiment 3 of the present disclosure. Fig. 17 is a front view of another member constituting the mounting mechanism 540 according to embodiment 3 of the present disclosure. Fig. 18 is a perspective view of another member constituting the mounting mechanism 540 according to embodiment 3 of the present disclosure.

In describing the attachment mechanism 540, the same components as those in embodiments 1 and 2 are denoted by the same reference numerals as in embodiments 1 and 2, and the description thereof will be given with reference to the same components.

As shown in fig. 14, the 3 rd inner peripheral surface 517 of the sleeve fixing nut 510 as the 1 st nut used in the attachment mechanism 540 includes an inclined surface 532b opposed to an inclined surface 532a of the tapered ring 530 as the annular body. In other words, the 3 rd inner peripheral surface 517 also serves as the inclined surface 532 b.

That is, in the following description, the inclined surface 532a of the tapered ring 530 as the annular body functions as the 1 st inclined surface. On the other hand, the inclined surface 532b of the cylindrical portion 510A functions as the 2 nd inclined surface.

The description is further detailed with reference to the drawings.

As shown in fig. 14, the sleeve fixing nut 510 includes a flange portion 510B and a cylindrical portion 510A. A 1 st thread groove 18 is formed in a 1 st inner peripheral surface 16 of the flange portion 510B facing the boss body 120. The cylindrical portion 510A has a 1 st outer circumferential surface 12 on the side opposite to the side where the boss body 120 is located. The 1 st thread ridge 14 is formed on the 1 st outer circumferential surface 12.

A 2 nd thread 122 is formed on an end portion 120b of the boss body 120 on the opposite side to the projection formed on the boss body 120 in the axial center J direction. The 2 nd thread ridge 122 is screw-coupled with the 1 st thread groove 18 formed at the sleeve fixing nut 510.

The lock nut 20 fixedly retains the sleeve retaining nut 510 to the sleeve body 120. A 2 nd thread groove 22 to be screwed with the 1 st thread 14 formed in the sleeve fixing nut 510 is formed in a part of the 2 nd inner peripheral surface 26 of the lock nut 20. The lock nut 20 has a small hole portion 24 to be fitted to the rotary shaft 110 at least in a part of the remaining portion of the 2 nd inner peripheral surface 26 of the lock nut 20.

Here, the cylindrical portion 510A of the sleeve fixing nut 510 is formed so as to form a gap portion 510C with the rotary shaft 110. The tapered ring 530 is inserted into the space 510C. The tapered ring 530 has an inclined surface 532a that is in contact with an inclined surface 532b of the cylindrical portion 510A. When the lock nut 20 is screwed in the direction D2 of the sleeve fixing nut 510, the inclined surface 532a of the tapered ring 530 is bored inward of the inclined surface 532b of the cylindrical portion 510A. In other words, in the cylindrical portion 510A, the inclined surface 532b of the cylindrical portion 510A slides out of the inclined surface 532a of the tapered ring 530. Thereby, in the direction intersecting with the axial center C, the cylindrical portion 510A moves in the direction away from the axial center C of the rotating shaft 110, and the outer diameter of the cylindrical portion 510A is enlarged. As a result, as shown in fig. 14, a force F1 acting outward in a direction intersecting the axial center C is generated in the cylindrical portion 510A having an outer diameter enlarged by the tapered ring 530 with respect to the hub fixing nut 510 and the lock nut 20. Thus, a reaction force F2 of the force F1 is generated in the sleeve body 120. As a result, the boss body 120 is strongly pressed toward the axial center C from all around the boss fixing nut 510 and the lock nut 20 in the direction intersecting the axial center C. That is, the shaft center J (rotation center) of the sleeve fixing nut 510, the lock nut 20, and the tapered ring 530 coincides with the shaft center C (rotation center) of the sleeve body 120. Therefore, the boss body 120 and the rotary plate 130, which are rotating bodies, can be prevented from radially jumping.

Further, it is preferable that the friction coefficient is large at the contact surface (sliding surface) where the inclined surface 532a of the tapered ring 530 and the inclined surface 532b of the cylindrical portion 510A contact each other.

As shown in fig. 15, preferably, the tapered ring 530 as an annular body has a slit 536 formed such that an extension line thereof intersects with the axis C. In other words, the tapered ring 530 as an annular body has a slit 536. Here, the extension line of the slit 536 is a line obtained by extending the slit 536, which is a narrow slit, in the cutting direction.

Alternatively, as shown in fig. 16 and 17, the tapered ring 530 as an annular body preferably has a plurality of slits 536 formed such that the extension line thereof intersects with the axis C. In other words, the tapered ring 530 has a plurality of slits 536. The respective extension lines of the plurality of slits 536 intersect the axial center C. In a plane orthogonal to the axis C, the plurality of slits 536 are preferably located at positions spaced apart from each other in the circumferential direction around the axis C.

Preferably, the slot 536 is formed along the angled surface 532 a. When the center line of the slit 536 is extended, the extended line preferably intersects the axis C.

In other words, on a plane orthogonal to the axial center C, the plurality of slits 536 are preferably located on the circumference at appropriate angles in the radial direction around the axial center C.

As a particularly preferable example, as shown in fig. 16, the slits 536 are preferably located at every θ 1 of 120 °. Alternatively, as shown in fig. 17, each slit 536 is preferably located at every θ 2 equal to 90 °.

In the specific example shown in fig. 16 and 17, the slits 536 are provided at equal intervals. The equal interval or the appropriate angle is sufficient if the holding force applied to the rotation shaft 110 by the inclined surfaces 532a separated by the slits 536 is equal, and is not intended to be mathematically equal. Typically, the unevenness due to the manufacturing tolerance is within the range of the equal interval or the appropriate angle in the present embodiment.

In this configuration, the tapered ring 530 can press the boss body 120 more strongly from the periphery of the boss fixing nut 510 and the lock nut 20 toward the axial center C in all directions in the direction intersecting the axial center C. That is, the tapered ring 530 can adjust the strength of fastening the boss body 120 within a range adjustable by the width dimension of the slit 536. Therefore, the accuracy is improved in which the axial centers J (rotational centers) of the sleeve fixing nut 510, the lock nut 20, and the tapered ring 30 are all aligned with the axial center C (rotational center) of the boss body 120. Therefore, the radial runout of the boss body 120 and the rotary plate 130 as the rotary bodies can be further suppressed.

In particular, when 3 slits 536 are formed as shown in fig. 16 and 4 slits 536 are formed as shown in fig. 17, a proper holding force is applied to the rotary shaft 110 from the inclined surface 532a divided by the slits. The man-hour of forming the slit 536 on the inclined surface 532a can be realized within a range of an appropriate man-hour.

As shown in fig. 18, the slit 536a preferably has a slit width W2 on the opening 536c side wider than a slit width W1 on the tip 536b side. In other words, the slit 536a of the taper ring 530 has a slit width W2 on the opening 536c side of the taper ring 530 wider than a slit width W1 on the tip 536b side of the taper ring 530.

In this configuration, even if a gap is generated between the inner peripheral surface of the tapered ring 530 and the outer peripheral surface of the rotary shaft 110 due to some cause, the gap can be absorbed by the difference between the slit width W2 and the slit width W1. That is, the tapered ring 530 and the rotary shaft 110 can always secure an appropriate holding force by the difference between the slit width W2 and the slit width W1.

As is clear from the above description, in embodiment 3 described above, the boss fixing nut 510 is formed in a shape obtained by combining the boss fixing nut 10 described in embodiment 1 and the outer ring 30 a. Thus, in the present configuration, the taper ring 530 functions as the inner ring 30b described in embodiment 1. That is, embodiment 3 can constitute the taper ring 530 by one member as compared with embodiment 1. Thus, embodiment 3 improves the workability of assembly as compared with the mounting mechanism 40 shown in embodiment 1.

As described above, the 3 rd inner peripheral surface 517 of the 1 st nut 510 used in the attachment mechanism 540 according to the present embodiment includes the 2 nd inclined surface corresponding to the inclined surface 532b, and the 2 nd inclined surface faces the 1 st inclined surface corresponding to the inclined surface 532 a.

This improves the workability of assembly of the attachment mechanism 540.

The tapered ring 530 as an annular body may have a slit 536 along the axis C.

The tapered ring 530 as an annular body may have a plurality of slits 536 formed in a direction along the axis C. In a plane orthogonal to the axis C, the plurality of slits 536 are preferably located at positions spaced apart from each other in the circumferential direction around the axis C.

In addition, it is preferable that the slit 536a of the annular tapered ring 530 has a slit width W2 on the opening 536c side of the annular tapered ring 530 be wider than a slit width W1 on the tip 536b side of the annular tapered ring 530.

(embodiment mode 4)

The structure of the mounting mechanism 640 of embodiment 4 will be described.

Fig. 19 is a schematic cross-sectional view showing an action on the rotating shaft 110 at the mounting mechanism 640 according to embodiment 4 of the present disclosure. Fig. 20 is a perspective view of one member constituting the mounting mechanism 640 according to embodiment 4 of the present disclosure. Fig. 21 is a front view of one member constituting the mounting mechanism 640 according to embodiment 4 of the present disclosure. Fig. 22 is a front view of another member constituting the mounting mechanism 640 of embodiment 4 of the present disclosure. Fig. 23 is a perspective view of another member constituting the mounting mechanism 640 according to embodiment 4 of the present disclosure.

In describing the attachment mechanism 640, the same components as those in embodiments 1 to 3 are denoted by the same reference numerals as in embodiments 1 to 3, and the description thereof will be given with reference to these components.

As shown in fig. 19, the 2 nd nut, i.e., the locknut 620 for the mounting mechanism 640 has a convex portion 622 reaching between the 2 nd inner peripheral surface 626 and the rotary shaft 110. The convex portion 622 includes an inclined surface 632a opposed to an inclined surface 632b of the tapered ring 630 as an annular body.

That is, in the following description, the inclined surface 632b of the taper ring 630 as the annular body functions as the 1 st inclined surface. On the other hand, the inclined surface 632a of the convex portion 622 functions as the 2 nd inclined surface.

This is explained in further detail using the drawings.

As shown in fig. 19, the sleeve fixing nut 10 includes a flange portion 10B and a cylindrical portion 10A. A 1 st thread groove 18 is formed in a 1 st inner peripheral surface 16 of the flange portion 10B facing the boss body 120. The cylindrical portion 10A has a 1 st outer peripheral surface 12 on the side opposite to the side where the boss body 120 is located. The 1 st thread ridge 14 is formed on the 1 st outer circumferential surface 12.

A 2 nd thread 122 is formed on an end portion 120b of the boss body 120 on the opposite side to the projection formed on the boss body 120 in the axial center J direction. The 2 nd thread ridge 122 is screw-coupled to the 1 st thread groove 18 formed in the sleeve fixing nut 10.

The lock nut 620 fixedly holds the sleeve fixing nut 10 to the sleeve body 120. A 2 nd thread groove 22 to be screwed with the 1 st thread 14 formed in the sleeve fixing nut 10 is formed in a part of the 2 nd inner peripheral surface 626 of the lock nut 620. The lock nut 620 has a small hole portion 24 to be fitted to the rotary shaft 110 at least in a part of the remaining portion of the 2 nd inner peripheral surface 626 of the lock nut 620.

Here, the cylindrical portion 10A of the sleeve fixing nut 10 is formed so as to form a gap 610C between itself and the rotary shaft 110. The tapered ring 630 is inserted into the space 610C. The taper ring 630 has an inclined surface 632b that abuts against an inclined surface 632a of the projection 622. When the lock nut 620 is screwed in the direction D2 of the sleeve fixing nut 10, the inclined surface 632b of the taper ring 630 is inserted into the inclined surface 632a of the projection 622. In other words, the inclined surface 632a of the projection 622 slides out of the inclined surface 632b of the taper ring 630. Accordingly, in the direction intersecting with the axial center C, the convex portion 622 moves in the direction away from the axial center C of the rotary shaft 110, and therefore the outer diameter of the convex portion 622 is enlarged. As a result, as shown in fig. 19, the convex portion 622 whose outer diameter is enlarged by the taper ring 630 generates a force F1 acting outward in a direction intersecting the axial center C with respect to the sleeve fixing nut 10. Thus, a reaction force F2 of the force F1 is generated in the sleeve body 120. As a result, the boss body 120 is strongly pressed toward the axial center C from all around the boss fixing nut 10 and the locknut 620 in the direction intersecting the axial center C. That is, the shaft center J (rotation center) of the sleeve fixing nut 10, the lock nut 620, and the tapered ring 630 coincides with the shaft center C (rotation center) of the sleeve body 120. Therefore, the boss body 120 and the rotary plate 130, which are rotating bodies, can be prevented from radially jumping.

Further, the friction coefficient is preferably large at the contact surface (sliding surface) where the inclined surface 632b of the tapered ring 630 and the inclined surface 632a of the convex portion 622 contact.

As shown in fig. 20, preferably, the tapered ring 630 as an annular body has a slit 636 formed such that an extension thereof intersects the axial center C. In other words, the tapered ring 630 as an annular body has a slit 636. Here, the extension line of the slit 636 is a line obtained by extending the slit 636, which is a narrow slit, in the cutting direction.

Alternatively, as shown in fig. 21 and 22, the tapered ring 630 as an annular body preferably has a plurality of slits 636 formed such that the extension line thereof intersects the axial center C. In other words, the conical ring 630 has a plurality of slits 636. The respective extension lines of the plurality of slits 636 intersect with the axis C. In a plane orthogonal to the axis C, the plurality of slits 636 are preferably located at positions spaced apart in the circumferential direction around the axis C.

The slit 436 is preferably formed along the inclined surface 632 b. When the center line of the slit 636 is extended, the extended line preferably intersects the axis C.

In other words, on a plane orthogonal to the axial center C, the plurality of slits 636 are preferably located on the circumference at appropriate angles in the radial direction around the axial center C.

As a particularly preferable example, as shown in fig. 21, each slit 636 is preferably located at every θ 1 of 120 °. Alternatively, as shown in fig. 22, each slit 636 is preferably located at every θ 2 equal to 90 °.

In the specific example shown in fig. 21 and 22, the slits 636 are provided at equal intervals. The equal intervals or the appropriate angles are not intended to be mathematically equal, as long as the holding forces applied to the rotary shaft 110 by the inclined surfaces 632b separated by the slits 636 are equal. Typically, the unevenness due to the manufacturing tolerance is within the range of the equal interval or the appropriate angle in the present embodiment.

In this configuration, the tapered portion 630 can press the boss body 120 more strongly from the periphery of the boss fixing nut 10 and the lock nut 20 toward the axial center C in all directions in the direction intersecting the axial center C. That is, the tapered portion 630 can adjust the strength of fastening the boss body 120 within a range adjustable by the width dimension of the slit 636. Therefore, the accuracy is improved in which the axial centers J (rotational centers) of the sleeve fixing nut 10, the locknut 620, and the tapered ring 630 coincide with the axial center C (rotational center) of the boss body 120. Therefore, the radial runout of the boss body 120 and the rotary plate 130 as the rotary bodies can be further suppressed.

In particular, when 3 slits 636 are formed as shown in fig. 21 and 4 slits 636 are formed as shown in fig. 22, a proper holding force is applied to the rotary shaft 110 from the inclined surface 632b divided by the slits. The man-hour of forming the slit 636 on the inclined surface 632b can be realized within a range of an appropriate man-hour.

As shown in fig. 23, the slit width W2 on the opening 636c side of the slit 636a is preferably wider than the slit width W1 on the tip 636b side. In other words, the slit width W2 on the opening 636c side of the taper ring 630 is wider than the slit width W1 on the tip 636b side of the taper ring 630 for the slit 636a of the taper ring 630.

In this configuration, even if a gap is generated between the inner peripheral surface of the tapered ring 630 and the outer peripheral surface of the rotary shaft 110 due to some cause, the gap can be absorbed by the difference between the slit width W2 and the slit width W1. That is, the tapered ring 630 and the rotary shaft 110 can always secure an appropriate holding force by the difference between the slit width W2 and the slit width W1.

As is clear from the above description, in embodiment 4 described above, the lock nut 620 is formed in a shape obtained by combining the lock nut 20 and the outer ring 30a described in embodiment 1. Thus, in the present configuration, the taper ring 630 functions as the inner ring 30b described in embodiment 1. That is, in embodiment 4, the taper ring 630 can be formed by one member as compared with embodiment 1. Thus, embodiment 4 improves the workability of assembly as compared with the mounting mechanism 40 shown in embodiment 1.

As described above, the 2 nd nut 620 used in the mounting mechanism 640 of the present embodiment has the convex portion 622 reaching between the 2 nd inner peripheral surface 626 and the rotary shaft 110. The convex portion 622 includes a 2 nd inclined surface corresponding to the inclined surface 632a, and the 2 nd inclined surface faces the 1 st inclined surface corresponding to the inclined surface 632 b.

The tapered ring 630 as an annular body may have a slit 636 along the axis C.

The tapered ring 630 as an annular body may have a plurality of slits 636 formed in a direction along the axis C. In a plane orthogonal to the axis C, the plurality of slits 636 are preferably located at positions spaced apart in the circumferential direction around the axis C.

In addition, it is preferable that the slit 636a of the ring-shaped taper ring 630 is wider than the slit width W2 on the opening 636c side of the ring-shaped taper ring 630 than the slit width W1 on the tip 636b side of the ring-shaped taper ring 630.

(embodiment 5)

The structure of the mounting mechanism of embodiment 5 will be described.

Fig. 24 is a front view of one member constituting the mounting mechanism of embodiment 5 of the present disclosure. Fig. 25 is a front view of another member constituting the mounting mechanism of embodiment 5 of the present disclosure.

In describing the mounting mechanism, the same components as those in embodiments 1 to 4 are denoted by the same reference numerals as in embodiments 1 to 4, and the description thereof will be given with reference to the drawings.

As shown in fig. 24, the tapered ring 730 as an annular body has a plurality of slits 736 on the inclined surface 732 b. The slits 736 are provided with openings 736C adjacent to each other at equal intervals in the circumferential direction around the axis C, when viewed from the direction of the axis C. The slits 736 are formed with notches, respectively, in a direction such that the notches are positioned at positions twisted with respect to the axis C. Thus, the distal ends 736b adjacent to each other are provided at equal intervals in the circumferential direction.

As shown in fig. 24, the slit forming the slit can be formed by a linear slit 736. Alternatively, as shown in fig. 25, the slit forming the slit may be formed by a spiral slit 736 a.

The

slits

736, 736a of this shape can be provided on the inclined surfaces shown in embodiments 1 to 4.

The

slits

736, 736a having this shape also provide the same advantageous effects as those of the above-described embodiments 1 to 4.

(one modification of the embodiment)

As a modification of the embodiment of the present disclosure, a known anti-loosening member such as a metal washer may be disposed between the facing surfaces of the flange portion 10B of the boss fixing nut 10 and the lock nut 20. With this arrangement, the rotational stability of the boss body 120 including the rotary plate 130 can be obtained over a long period of time.

Industrial applicability

The mounting mechanism of the present disclosure can mount a rotating body in a device including the rotating body to a rotatable shaft body. The mounting mechanism of the present disclosure can be used, for example, for detection of the rotational position of a servo system. The mounting mechanism of the present disclosure is useful for an encoder or the like that detects the absolute position of a tool or the like of a machine tool with high accuracy and high resolution.

Description of the reference numerals

10. 510, a shaft sleeve fixing nut (No. 1 nut); 10A, 510A, cylindrical portion; 10B, 510B, flange portion; 10C, 410C, 510C, 610C, void; 10d, 20a, inner surface; 12. 1 st peripheral surface; 14. 1, a first thread tooth; 16. 1 st inner peripheral surface; 17. 517 and the 3 rd inner peripheral surface; 18. 1 st thread groove; 20. 620, a lock nut (No. 2 nut); 22. the 2 nd thread groove; 24. a small hole portion; 26. 626, 2 nd inner circumferential surface; 30. 430, 530, 630, 730, tapered rings (rings); 30a, an outer ring; 30b, an inner ring; 32. 32a, 32b, 432a, 432b, 532a, 532b, 632a, 632b, 732b, inclined surface; 34. 34a, 120c, end faces; 36. 36a, 436a, 536a, 636a, 736a, slit; 36b, 436b, 536b, 636b, 736b, tip; 36c, 436c, 536c, 636c, 736c, opening; 40. 440, 540, 640, mounting mechanism; 100. an encoder; 100a, a housing; 110. a rotating shaft; 120. 460, shaft sleeve body (rotator); 120a, a protrusion; 120b, 460b, end; 122. the 2 nd thread tooth; 124. the 2 nd outer peripheral surface; 130. a rotating plate (rotating body); 131. a light transmissive window; 140. a bearing mechanism; 151. an LED element (light emitting element); 152. a phototransistor (light receiving element); 200. an electric motor; 210. a rotor; 212. a rotor core; 214. a magnet bore; 216. a permanent magnet; 220. a bearing; 222. a box body; 230. a stator; 232. a stator core; 234. a winding; 236. an insulating member; 462. a tapered portion; 622. a convex portion.

Claims

1. A mounting mechanism for mounting a rotating body to a rotating shaft,

the mounting mechanism includes:

a 1 st nut including a cylindrical portion and a flange portion, wherein the rotating shaft penetrates through the cylindrical portion, the cylindrical portion extends along an axial center of the rotating shaft and has a 1 st outer circumferential surface including a 1 st thread, the flange portion protrudes in a direction intersecting the axial center and in a direction opposite to a side where the rotating shaft is located, and the flange portion has a 1 st inner circumferential surface including a 1 st thread groove;

a 2 nd nut through which the rotation shaft passes, the 2 nd nut including a 2 nd thread groove and a small hole portion, the 2 nd thread groove being formed in a part of a 2 nd inner peripheral surface of the 2 nd nut facing the rotation shaft and being screwed to the 1 st thread, the small hole portion being formed in a part of the 2 nd inner peripheral surface other than the 2 nd thread groove and being fitted to the rotation shaft; and

an annular body having a 1 st inclined surface, the rotating shaft penetrating the annular body and the annular body being positioned between the rotating shaft and a 3 rd inner circumferential surface of the cylindrical portion, the 1 st inclined surface converting a force acting in a direction along the axis from each of the 1 st nut and the 2 nd nut into a force acting in a direction intersecting the axis when the 1 st nut and the 2 nd nut are screwed together in a direction in which they approach each other,

the rotating body is a shaft sleeve body or an encoder comprising the shaft sleeve body and a rotating plate.

2. The mounting mechanism of claim 1 wherein,

the annular body is a pair of tapered rings further having a 2 nd inclined surface that is in contact with the 1 st inclined surface in an opposed manner.

3. The mounting mechanism of claim 2 wherein,

the tapered ring of the pair of tapered rings on the side of the rotation shaft has a slit, and an extension line of the slit intersects with the shaft center.

4. The mounting mechanism of claim 2 wherein,

a tapered ring located on the rotation shaft side of the pair of tapered rings has a plurality of slits, extension lines of the plurality of slits intersect with the shaft center,

the plurality of slits are located at positions spaced apart from each other in a circumferential direction around the axis on a plane orthogonal to the axis.

5. The mounting mechanism of claim 3 or 4,

the slit of the tapered ring located on the rotation axis side has a slit width on the opening side of the tapered ring that is wider than a slit width on the tip side of the tapered ring.

6. The mounting mechanism of claim 1 wherein,

the rotating body has a tapered portion extending in a direction along the axial center between the 3 rd inner peripheral surface and the rotating shaft,

the tapered portion includes a 2 nd inclined surface opposite the 1 st inclined surface.

7. The mounting mechanism of claim 6 wherein,

the tapered portion has a slit, and an extension line of the slit intersects with the axis.

8. The mounting mechanism of claim 6 wherein,

the tapered portion has a plurality of slits, extension lines of the slits respectively intersect with the axis,

9. The mounting mechanism of claim 7 or 8,

the slit of the tapered portion has a slit width on the opening side of the tapered portion that is wider than a slit width on the tip side of the tapered portion.

10. The mounting mechanism of claim 1 wherein,

the 3 rd inner peripheral surface of the 1 st nut includes a 2 nd inclined surface opposite to the 1 st inclined surface.

11. The mounting mechanism of claim 1 wherein,

the 2 nd nut further has a convex portion reaching between the 2 nd inner peripheral surface and the rotary shaft, and the convex portion includes a 2 nd inclined surface opposite to the 1 st inclined surface.

12. The mounting mechanism of claim 10 or 11,

the annular body has a slit along the axis.

13. The mounting mechanism of claim 10 or 11,

the annular body has a plurality of slits formed in a direction along the axis,

the plurality of slits are provided at equal intervals in a circumferential direction around the axis on a plane orthogonal to the axis.

14. The mounting mechanism of claim 12 wherein,

the slit of the annular body has a slit width on the opening side of the annular body that is wider than a slit width on the tip side of the annular body.

15. The mounting mechanism of any of claims 1, 2, 6, 10, and 11,

the rotating body is an encoder comprising a shaft sleeve body and a rotating plate,

the shaft sleeve body extends along the axis of the shaft and has a 2 nd outer peripheral surface, the 2 nd outer peripheral surface includes a 2 nd thread tooth that is screwed with the 1 st thread groove included in the flange portion,

the rotating plate is installed in a manner of intersecting the axis.

16. An electric motor, wherein,

the motor includes:

a rotor having a rotor core attached to the rotating shaft;

a bearing that rotatably supports the rotating shaft; and

a stator located at a position opposite to the rotor,

the encoder is mounted to the rotating shaft using the mounting mechanism of claim 15.