JP6637796B2 - Pulley device - Google Patents

Description

  The present invention relates to a pulley device.

  In scooter type motorcycles and the like, a belt-type continuously variable transmission is employed. This continuously variable transmission includes a driving pulley device, a driven pulley device, and a belt. The belt is suspended between the driving pulley device and the driven pulley device.

  The driven pulley device has a fixed sheave, a movable sheave, a fixed boss, and a movable boss (Patent Document 1). The belt is held between the fixed sheave and the movable sheave. The movable boss is fixed to the movable sheave, and the fixed boss is fixed to the fixed sheave. Generally, the fixing boss and the fixing sheave are made of iron, and are fixed to each other by welding. The drive plate is fastened to the fixed boss by a nut screwed into a screw formed at the tip of the fixed boss.

  In order to reduce the manufacturing cost of the pulley device, it has been proposed that a fixed boss and a fixed sheave are integrally formed by aluminum die casting, as in a pulley device described in Patent Document 2, for example.

JP-A-8-86342 Japanese Patent No. 3412741

  However, when the fixed boss and the fixed sheave are integrally formed by aluminum die casting, the strength is reduced as compared with the iron fixed boss. For this reason, the strength with respect to the fastening force of the nut may be insufficient. In view of the above, an object of the present invention is to provide a pulley device having improved strength with respect to a fastening force of a nut.

  A pulley device according to an aspect of the present invention includes a fixed sheave, a fixed boss, a mounting member, a drive plate, and a nut member. The fixed boss is formed integrally with the fixed sheave. The fixed boss has a cylindrical boss body and an inner flange. The boss body extends from the fixed sheave to a first side in the axial direction. The inner flange portion extends radially inward from the first axial end of the boss body. The attachment member is detachably attached to the fixed boss so as to be integrally rotatable. The mounting member has a cylindrical mounting body and an outer flange. The mounting body protrudes from the inside of the fixed boss toward the first side in the axial direction, and has a threaded portion formed on the outer peripheral surface. The outer flange portion extends radially outward from the second axial end of the mounting body, and is engaged with the inner flange portion. The drive plate rotates integrally with the fixed boss. The nut member is screwed with the screw portion of the mounting body to fasten the drive plate.

  According to this configuration, the nut member is not attached to the fixed boss, but is screwed to the attachment member that rotates integrally with the fixed boss. For this reason, for example, the fixed boss and the fixed sheave can be made of an aluminum alloy which is easily formed integrally with each other, and the mounting member to which the nut member is mounted can be made of iron to ensure strength. Thus, according to the present invention, the strength of the nut with respect to the fastening force is improved.

  Preferably, the pulley device further includes a bearing member. The bearing member is disposed in the boss body, and sandwiches the outer flange with the inner flange.

  Preferably, the outer peripheral surface of the bearing member contacts the inner peripheral surface of the boss body.

  Preferably, the pulley device further includes a retaining ring that restricts the movement of the bearing member to the second side in the axial direction.

  Preferably, the drive plate is mounted on the mounting body.

  Preferably, the mounting body has a pair of flat surfaces extending parallel to each other on the outer peripheral surface. The inner flange engages a pair of flat surfaces.

  Preferably, the drive plate engages a pair of flat surfaces of the mounting body.

  ADVANTAGE OF THE INVENTION According to this invention, the intensity | strength with respect to the fastening force of a nut can be improved.

FIG. 3 is a side sectional view of the pulley device. FIG. 4 is a side sectional view showing details of a fixed boss. The rear view which shows the engagement state of a fixing boss and an attachment member. FIG. 4 is a side sectional view showing details of a fixed boss. FIG. 3 is a side sectional view showing details of a movable boss. The side view of a seal member. The top view of a spring seat. FIG. 8 is a sectional view taken along line VIII-VIII in FIG. 7. FIG. 3 is a schematic diagram showing a cam mechanism. The rear view of a drive plate. Sectional drawing of the seal member which concerns on a modification. The front view of the seal member concerning a modification.

  Hereinafter, an embodiment of a pulley device according to the present invention will be described with reference to the drawings. The pulley device 100 according to the present embodiment is a driven pulley device 100. Torque is transmitted to the driven side pulley device 100 via a belt 120 from a drive side pulley device (not shown). The belt 120 is a member for transmitting torque.

  FIG. 1 is a side sectional view of the pulley device 100. In the following description, the rotation axis O means the rotation axis of the pulley device 100. The axial direction refers to the direction in which the rotation axis O extends. The first side in the axial direction means the left side in FIG. 1, and the second side in the axial direction means the right side in FIG. The radial direction means the radial direction of a circle centered on the rotation axis O. The term “radially outside” means a side away from the rotation axis O in the radial direction, and the term “radially inside” means a side approaching the rotation axis O in the radial direction. The circumferential direction refers to the circumferential direction of a circle around the rotation axis O.

[Pulley device]
As shown in FIG. 1, the pulley device 100 includes a fixed sheave 1, a fixed boss 2, a mounting member 3, a movable sheave 4, a movable boss 5, a nut member 104, and a centrifugal clutch 10. . The pulley device 100 also includes a first elastic member 6a, a second elastic member 6b, a first seal member 7a, a second seal member 7b, a cam mechanism 8, a spring 90, a spring seat 9, and the like.

[Fixed sheave]
The fixed sheave 1 is arranged so as to rotate about a rotation axis O. The central axis of the fixed sheave 1 is disposed substantially coaxially with the rotation axis O. The fixed sheave 1 is arranged on the second side of the movable sheave 4 in the axial direction. The fixed sheave 1 is fixed so as not to move in the axial direction.

  The fixed sheave 1 has a disk shape. The facing surface 11 of the fixed sheave 1 is inclined so as to move away from the movable sheave 4 as going outward in the radial direction. That is, the facing surface 11 is inclined toward the second side in the axial direction toward the outside in the radial direction. The facing surface 11 of the fixed sheave 1 is a surface facing the movable sheave 4. That is, the facing surface 11 of the fixed sheave 1 faces the first side in the axial direction.

[Fixed boss]
As shown in FIG. 2, the fixed boss 2 rotates integrally with the fixed sheave 1. The fixed boss 2 is formed integrally with the fixed sheave 1. That is, the fixed sheave 1 and the fixed boss 2 are formed by one member. For example, the fixed boss 2 is made of an aluminum alloy. The fixed boss 2 has a cylindrical shape and extends from the fixed sheave 1 to a first side in the axial direction. The central axis of the fixed boss 2 is disposed substantially coaxially with the rotation axis O.

  The fixed boss 2 has a boss main body 21 and an inner flange 22. The boss body 21 has a cylindrical shape extending in the axial direction. The boss body 21 extends from the fixed sheave 1 to a first side in the axial direction. A fitting groove 211 is formed on the inner peripheral surface of the boss body 21. The fitting groove 211 has an annular shape extending in the circumferential direction along the inner circumferential surface.

  The inner flange portion 22 extends radially inward from the first axial end of the boss body 21. The inner flange portion 22 is annular.

[Mounting member]
The attachment member 3 is detachably attached to the fixed boss 2 and is integrally rotatable. The attachment member 3 is a separate member from the fixed boss 2 and is slidable inside the fixed boss 2 with the first bearing member 110 and the retaining ring 111 removed. That is, the mounting member 3 and the fixed boss 2 are not joined. The attachment member 3 is made of, for example, metal, and is preferably made of iron or steel.

  The mounting member 3 has a mounting body 31 and an outer flange 32. The mounting body 31 protrudes from the inside of the fixed boss 2 to the first side in the axial direction. More specifically, the mounting body 31 protrudes from the inside of the fixed boss 2 to the first side in the axial direction beyond the inner flange portion 22.

  The mounting body 31 has a cylindrical shape, and a screw portion 311 is formed on the outer peripheral surface. The screw portion 311 is formed at the first axial end of the mounting body 31.

  As shown in FIG. 3, the mounting main body 31 has a pair of first flat surfaces 312 extending in parallel with each other on the outer peripheral surface. Each first flat surface 312 extends parallel to the axial direction. The engagement between the first flat surface 312 and the inner flange portion 22 causes the fixed boss 2 and the mounting member 3 to rotate integrally. Specifically, the inner flange portion 22 has a pair of second flat surfaces 221 extending in parallel with each other on the inner peripheral surface. Each second flat surface 221 of the inner flange portion 22 is in contact with each first flat surface 312 of the mounting body 31. The inner peripheral surface of the inner flange portion 22 and the outer peripheral surface of the mounting body 31 have the same shape when viewed in the axial direction. For this reason, the fixed boss 2 and the mounting member 3 are engaged with each other and rotate integrally with each other.

  As shown in FIG. 2, the outer flange 32 extends radially outward from the second axial end of the mounting body 31. The outer flange portion 32 is annular. Outer flange 32 engages inner flange 22. Specifically, the outer flange portion 32 is disposed on the second side of the inner flange portion 22 in the axial direction. The outer diameter of the outer flange 32 is larger than the inner diameter of the inner flange 22. The outer diameter of the outer flange 32 is substantially the same as the inner diameter of the boss body 21. The inner diameter of the inner flange portion 22 is substantially the same as the outer diameter of the mounting body 31. In the axial direction, the outer flange portion 32 contacts the inner flange portion 22. As a result, the mounting member 3 is engaged with the first side in the axial direction so as not to come off.

  The mounting member 3 configured as described above is inserted into the fixed boss 2 from the second side in the axial direction. Then, when the mounting member 3 is inserted to the first axial end in the fixed boss 2, the mounting main body 31 projects from the fixed boss 2 to the first axial side. The outer flange 32 engages with the inner flange 22 inside the fixed boss 2. For this reason, the mounting member 3 does not fall out of the fixed boss 2 to the first side in the axial direction.

[Bearing member]
As shown in FIG. 4, a first bearing member 110 (an example of a bearing member) is disposed in the boss body 21 of the fixed boss 2. The outer flange 32 is sandwiched between the first bearing member 110 and the inner flange 22. The outer peripheral surface of the first bearing member 110 contacts the inner peripheral surface of the boss body 21. Preferably, first bearing member 110 is press-fitted into boss body 21. According to this, the first bearing member 110 can restrict the mounting member 3 from moving to the second side in the axial direction. That is, the movement of the mounting member 3 in the axial direction is restricted by the inner flange portion 22 and the first bearing member 110. The first bearing member 110 supports an output shaft (not shown) extending inside the fixed boss 2 for relative rotation with respect to the fixed boss 2. The output shaft is, for example, a shaft for transmitting torque to the rear wheel, and is also supported by the second bearing member 112 (see FIG. 1).

[Retaining ring]
The retaining ring 111 restricts the movement of the first bearing member 110 to the second side in the axial direction. The retaining ring 111 is fitted in the fitting groove 211 and does not move in the axial direction from the fitting groove 211. For this reason, the retaining ring 111 can reliably restrict the movement of the first bearing member 110 and the mounting member 3 to the second side in the axial direction. The retaining ring 111 has an inner diameter smaller than the outer diameter of the first bearing member 110. The inner flange portion 22, the outer flange portion 32, the first bearing member 110, and the retaining ring 111 are arranged in this order from the first side in the axial direction.

[Movable sheave]
As shown in FIG. 1, the movable sheave 4 is arranged to rotate about a rotation axis O. The central axis of the movable sheave 4 is arranged substantially coaxially with the rotation axis O. The movable sheave 4 is arranged to move along the rotation axis O. That is, the movable sheave 4 is arranged so as to move in the axial direction. The movable sheave 4 moves toward and away from the fixed sheave 1 by moving in the axial direction. The movable sheave 4 is arranged on the first side of the fixed sheave 1 in the axial direction.

  The movable sheave 4 has a disk shape. The facing surface 41 of the movable sheave 4 is inclined so as to move away from the fixed sheave 1 as going outward in the radial direction. That is, the facing surface 41 is inclined toward the first side in the axial direction toward the outside in the radial direction.

  The facing surface 41 of the movable sheave 4 is a surface facing the fixed sheave 1. That is, the opposing surface 41 of the movable sheave 4 faces the second side in the axial direction. The opposing surface 11 of the fixed sheave 1 and the opposing surface 41 of the movable sheave 4 oppose each other with an interval. The facing surface 11 of the fixed sheave 1 and the facing surface 41 of the movable sheave 4 form a V groove. As the movable sheave 4 moves in the axial direction, the groove width of the V groove changes. The belt 120 is disposed in the V groove. The belt 120 is sandwiched between the opposing surface 11 of the fixed sheave 1 and the opposing surface 41 of the movable sheave 4.

  The movable sheave 4 has an annular support wall portion 42 protruding toward the first side in the axial direction. This support wall portion 42 is disposed radially outside the movable boss 5. The end of the spring 90 is arranged between the support wall 42 and the movable boss 5.

[Movable boss]
The movable boss 5 rotates integrally with the movable sheave 4. Further, the movable boss 5 moves integrally with the movable sheave 4 in the axial direction. In the present embodiment, the movable boss 5 and the movable sheave 4 are formed by one member. Note that the movable boss 5 and the movable sheave 4 are formed by separate members, respectively, and may be integrally rotated and axially moved by being fixed to each other. For example, the movable sheave 4 and the movable boss 5 can be fixed by welding or brazing.

  The movable boss 5 has a cylindrical shape and extends in the axial direction from the movable sheave 4. Specifically, the movable boss 5 extends from the movable sheave 4 to the first side in the axial direction. That is, the movable boss 5 extends in a direction away from the fixed sheave 1. The center axis of the movable boss 5 is arranged substantially coaxially with the rotation axis O. The movable boss 5 is arranged radially outside the fixed boss 2. That is, the fixed boss 2 extends in the movable boss 5 in the axial direction. The movable boss 5 is slidably disposed on the fixed boss 2.

  As shown in FIG. 5, the movable boss 5 has a first inner peripheral surface 51 and a second inner peripheral surface 52. The first inner peripheral surface 51 is arranged on the first axial side of the second inner peripheral surface 52. The inner diameter of the movable boss 5 on the first inner peripheral surface 51 is smaller than the inner diameter of the movable boss 5 on the second inner peripheral surface 52. That is, the first inner peripheral surface 51 is disposed radially inward of the second inner peripheral surface 52. Therefore, a step 53 is formed between the first inner peripheral surface 51 and the second inner peripheral surface 52.

  The movable boss 5 has a first accommodation groove 54 and a second accommodation groove 55. The first accommodation groove 54 is formed on the first inner peripheral surface 51. The first accommodation groove 54 is annular and extends in the circumferential direction.

  The second accommodation groove 55 is formed on the second inner peripheral surface 52. The second accommodation groove 55 is annular and extends in the circumferential direction. The second accommodation groove 55 is arranged at the second side end of the movable boss 5 in the axial direction. The first accommodation groove 54 and the second accommodation groove 55 are arranged at intervals in the axial direction. A sliding member 50 described below is arranged between the first accommodation groove 54 and the second accommodation groove 55. The first accommodation groove 54 and the second accommodation groove 55 have substantially the same diameter. For this reason, the depth of the first storage groove 54 is larger than the depth of the second storage groove 55.

  The movable boss 5 has a plurality of cam portions 81 formed at the first side end in the axial direction. Each cam portion 81 is arranged at intervals in the circumferential direction. Each cam portion 81 extends to the first side in the axial direction.

  The movable boss 5 is made of, for example, metal. Specifically, the movable boss 5 is made of steel or an aluminum alloy. More specifically, the movable boss 5 is formed of at least one selected from the group consisting of carbon steel and alloy steel.

  As shown in FIG. 1, the movable boss 5 can slide on the fixed boss 2 without using grease. Specifically, a sliding member 50 is attached to the inner peripheral surface of the movable boss 5. The movable boss 5 slides on the fixed boss 2 via the sliding member 50. The sliding member 50 has a lower coefficient of friction than the movable boss 5.

[Sliding member]
The sliding member 50 is attached to the inner peripheral surface of the movable boss 5. Specifically, the sliding member 50 is attached to the second inner peripheral surface 52 of the movable boss 5. The sliding member 50 has a cylindrical shape. The outer peripheral surface of the sliding member 50 is in contact with the second inner peripheral surface 52 of the movable boss 5. The inner peripheral surface of the sliding member 50 is in contact with the outer peripheral surface of the fixed boss 2.

  The sliding member 50 is in contact with the step 53. The step 53 restricts the movement of the sliding member 50 to the first side in the axial direction. In addition, movement of the sliding member 50 to the second side in the axial direction is restricted by a retaining ring or the like. For example, the sliding member 50 is inserted into the movable boss 5 from the second side in the axial direction, and then a retaining ring is attached.

  The sliding member 50 is made of, for example, a resin. The sliding member 50 may include a metal layer and a sintered body layer formed on the outer peripheral surface of the resin layer while having the resin layer. The friction coefficient of the sliding member 50 is smaller than the friction coefficient of the movable boss 5. Specifically, the sliding member 50 is formed of at least one selected from the group consisting of a nylon resin, a fluororesin, a polyetheretherketone resin, and a polyphenylenesulfide resin. As described above, since the sliding member 50 has a smaller coefficient of friction than the movable boss 5, the movable boss 5 can smoothly slide on the fixed boss 2 via the sliding member 50.

[Elastic member]
The first elastic member 6a is annular and is disposed in the first accommodation groove 54. The first elastic member 6a is, for example, an O-ring. The second elastic member 6b is annular and is disposed in the second accommodation groove 55. The second elastic member 6b has the same configuration as that of the first elastic member 6a except for the location, and a detailed description is omitted.

[Seal member]
The first seal member 7a is arranged between the first elastic member 6a and the fixed boss 2 in the radial direction. The first seal member 7a is urged radially inward by the first elastic member 6a. For this reason, the first seal member 7a reliably contacts the fixed boss 2 to prevent intrusion of dust and the like.

  As shown in FIG. 6, the first seal member 7a is annular. The first seal member 7a has a first end 71 and a second end 72 in the circumferential direction. The first end 71 and the second end 72 are spaced from each other in the circumferential direction. Since the first seal member 7a is not an endless ring as described above, its diameter can be changed.

  When viewed in the axial direction, the first end 71 and the second end 72 overlap each other. For this reason, the gap between the first end 71 and the second end 72 does not extend linearly in the axial direction. That is, the first end 71 and the second end 72 form a labyrinth structure. As a result, the first seal member 7a can reliably prevent dust from entering.

  The first end 71 has a first protrusion 711 extending in the circumferential direction. The second end 72 has a second protrusion 721 extending in the circumferential direction. The first protrusion 711 and the second protrusion 721 are in contact with each other in the axial direction. The boundary 73 between the first protrusion 711 and the second protrusion 721 extends in the circumferential direction. This boundary line 73 is displaced in the axial direction with respect to the axial center C of the first seal member 7a. For example, the width of the first protrusion 711 is larger than that of the second protrusion 721. Note that the widths of the protrusions 711 and 721 mean dimensions in the axial direction.

  When the first elastic member 6a is an O-ring or the like, the first elastic member 6a contacts the outer peripheral surface of the first seal member 7a at the center C in the axial direction of the first seal member 7a. Therefore, the first elastic member 6a does not contact the boundary line 73. As a result, the first elastic member 6a can be prevented from being damaged by the boundary line 73.

  The first seal member 7a has a seal body 74, a first wall 75, and a second wall 76. The seal body 74 is annular. The inner peripheral surface of the seal body 74 contacts the outer peripheral surface of the fixed boss 2.

  The first wall 75 is annular and extends radially outward from the seal body 74. More specifically, the first wall 75 extends radially outward from one axial end of the seal body 74. The first wall portion 75 is disposed between one inner wall surface of the first accommodation groove 54 and the first elastic member 6a.

  The second wall 76 is annular and extends radially outward from the seal body 74. More specifically, the second wall 76 extends radially outward from the other axial end of the seal body 74. The second wall portion 76 is arranged at an interval from the first wall portion 75 in the axial direction. The second wall portion 76 is disposed between the other inner wall surface of the first housing groove 54 and the first elastic member 6a. The first elastic member 6a is disposed in a groove defined by the seal body 74, the first wall 75, and the second wall 76.

  The first seal member 7a has a smaller coefficient of friction than the first elastic member 6a. The first seal member 7a is made of, for example, a resin. More specifically, the first seal member 7a is formed of at least one selected from the group consisting of a nylon resin, a fluorine resin, a polyetheretherketone resin, and a polyphenylene sulfide resin.

  Since the second seal member 7b has the same configuration as the first seal member 7a except for the location, a detailed description is omitted.

[spring]
As shown in FIG. 1, the spring 90 urges the movable sheave 4 toward the fixed sheave 1 in the axial direction. That is, the spring 90 urges the movable sheave 4 toward the second side in the axial direction. Thus, the fixed sheave 1 and the movable sheave 4 sandwich the belt 120. The spring 90 can be, for example, a coil spring. The spring 90 is disposed radially outside the movable boss 5 so as to surround the movable boss 5.

[Spring seat]
The spring seat 9 is configured to support the spring 90. As shown in FIGS. 7 and 8, the spring seat 9 has a cylindrical portion 91, a flange portion 92, and a plurality of cam receiving portions 82. The spring seat 9 is made of, for example, resin. Specifically, the spring sheet 9 is at least one selected from the group consisting of a nylon resin, a fluororesin, a polyetheretherketone resin, and a polyphenylenesulfide resin. The cylindrical portion 91, the flange portion 92, and each cam receiving portion 82 are integrally formed by one member.

  The cylindrical portion 91 is disposed radially outside the movable boss 5. The cylindrical portion 91 is disposed radially inside the spring 90. That is, the cylindrical portion 91 is disposed between the movable boss 5 and the spring 90 in the radial direction. The cylindrical portion 91 supports the spring 90 in the radial direction.

  The flange portion 92 extends radially outward from the cylindrical portion 91. Specifically, the flange portion 92 extends radially outward from an end of the cylindrical portion 91 on the first side in the axial direction. The flange portion 92 is annular. The flange portion 92 supports an end surface on the first side in the axial direction of the spring 90. That is, the flange portion 92 supports the spring 90 in the axial direction.

  Each cam receiving portion 82 is arranged inside the cylindrical portion 91 in the radial direction. Specifically, each cam receiving portion 82 is formed on the inner peripheral surface of the cylindrical portion 91. Each cam receiving portion 82 extends in the circumferential direction. The respective cam receiving portions 82 are arranged at intervals in the circumferential direction. The cam portion 81 extends between the adjacent cam receiving portions 82 in the circumferential direction. Each cam receiving portion 82 engages with each cam portion 81 of the movable boss 5. Each cam receiving portion 82 constitutes a cam mechanism 8. Each cam receiving portion 82 has a concave portion 821. The recess 821 extends in the radial direction. The recess 821 accommodates a part of the drive plate 101 described later.

  The spring seat 9 rotates integrally with the fixed sheave 1. Specifically, the spring seat 9 has a projecting portion 93 projecting to the first side in the axial direction. The protrusion 93 fits into a through hole 1011 (see FIG. 10) of the drive plate 101 described later. The protrusion 93 has a shape along the outer peripheral edge of the through hole 1011. The drive plate 101 rotates integrally with the fixed sheave 1 via the fixed boss 2. Therefore, the spring seat 9 attached to the drive plate 101 rotates integrally with the fixed sheave 1.

[Cam mechanism]
As shown in FIG. 1, the cam mechanism 8 is provided on the movable boss 5 and the spring seat 9. Specifically, the cam mechanism 8 includes a plurality of cam portions 81 and a plurality of cam receiving portions 82. The cam portion 81 is formed on the movable boss 5 described above. Further, the cam receiving portion 82 is formed on the spring seat 9. The cam mechanism 8 is configured to convert a relative rotation of the movable boss 5 with respect to the fixed boss 2 into an axial thrust of the movable boss 5. That is, when the movable boss 5 rotates at a higher speed than the fixed boss 2, the cam mechanism 8 moves the movable boss 5 toward the fixed sheave 1.

  More specifically, as shown in FIG. 9, each cam portion 81 of the movable boss 5 has a cam surface 811. The cam surface 811 is inclined so as to face the rotation direction and face the first side in the axial direction. The cam surface 811 contacts the cam receiving portion 82 of the spring seat 9. Note that the rotation direction is a direction in which the movable boss 5 rotates when the vehicle moves forward.

[Centrifugal clutch]
As shown in FIG. 1, the centrifugal clutch 10 includes a drive plate 101, a plurality of clutch shoes 102, and a clutch housing 103. The centrifugal clutch 10 is configured to transmit or block the rotation of the fixed sheave 1 and the movable sheave 4 to an output shaft. Specifically, the centrifugal clutch 10 is configured to transmit or block the rotation of the fixed boss 2 to the output shaft.

  The drive plate 101 is mounted on the mounting member 3. As shown in FIG. 10, the drive plate 101 has a mounting hole 1012 that engages with the pair of first flat surfaces 312 of the mounting body 31. When viewed in the axial direction, the shape of the mounting hole 1012 is substantially the same as the shape of the mounting body 31. That is, the inner peripheral surface of the mounting hole 1012 has a pair of third flat surfaces 1013 extending parallel to each other. Therefore, the drive plate 101 rotates integrally with the fixed boss 2. The drive plate 101 has a disk shape. The drive plate 101 is configured to have substantially no step, but the drive plate 101 may have a step.

  The drive plate 101 has a plurality of through holes 1011. Each through hole 1011 penetrates in the axial direction. Each through hole 1011 extends in the circumferential direction. Each through-hole 1011 is arranged at intervals in the circumferential direction. The protrusion 93 of the spring seat 9 described above is fitted into the through hole 1011. Each cam 81 of the movable boss 5 extends in the through hole 1011 so as not to interfere with the drive plate 101. In addition, a part of the drive plate 101 arranged between the adjacent through holes 1011 is housed in the recess 821 of the cam receiving portion 82 described above.

  The drive plate 101 is made of metal. Specifically, drive plate 101 is made of steel or an aluminum alloy. More specifically, drive plate 101 is at least one selected from the group consisting of carbon steel and alloy steel.

  As shown in FIG. 1, when the drive plate 101 comes into contact with the inner flange portion 22, the movement to the second side in the axial direction is restricted. The drive plate 101 is fastened by a nut member 104. As a result, the movement of the drive plate 101 to the first side in the axial direction is restricted.

  One end of each clutch shoe 102 in the circumferential direction is swingably attached to the drive plate 101. Each clutch shoe 102 has a friction material (not shown) on its outer peripheral surface. A return spring (not shown) is attached to the other end of each clutch shoe 102 so as to bias each clutch shoe 102 inward in the radial direction.

  The clutch housing 103 is arranged so as to cover each clutch shoe 102 from the outside in the radial direction. The clutch housing 103 is rotatable relative to the fixed boss 2. Specifically, the clutch housing 103 has a boss 1031. The boss 1031 has a spline hole 1032 formed therein. The output shaft can be spline-engaged with the spline hole 1032.

  When the centrifugal clutch 10 is in the transmission state, the friction material of each clutch shoe 102 frictionally engages with the inner peripheral surface of the clutch housing 103. When the centrifugal clutch 10 is in the disengaged state, the friction material of each clutch shoe 102 separates from the inner peripheral surface of the clutch housing 103. The transmission state of the centrifugal clutch 10 means a state where the centrifugal clutch 10 transmits the rotation of the fixed sheave 1 and the movable sheave 4 to the output shaft. The disconnected state of the centrifugal clutch 10 means a state in which the centrifugal clutch 10 does not transmit the rotation of the fixed sheave 1 and the movable sheave 4 to the output shaft.

[Nut member]
As shown in FIG. 2, the nut member 104 is screwed with a screw portion 311 formed on the mounting body 31 of the mounting member 3. Then, the nut member 104 fastens the drive plate 101 to the fixed boss 2. That is, the drive plate 101 is fixed between the fixing boss 2 and the nut member 104.

  The pulley device configured as described above operates as follows.

  In the pulley device on the driving side, when the width of the groove formed by the fixed sheave and the movable sheave is reduced, the winding diameter of the belt 120 is increased. That is, the belt 120 moves radially outward in the drive-side pulley device.

  In the driven pulley device 100, the width of the groove formed by the fixed sheave 1 and the movable sheave 4 operates in the opposite direction to the groove width in the drive side pulley device. That is, when the belt 120 moves radially outward in the driving pulley device, the belt 120 moves radially inward in the driven pulley device 100.

  When the belt 120 moves inward in the radial direction, the movable sheave 4 moves in a direction away from the fixed sheave 1 against the urging force of the spring 90. That is, the movable sheave 4 moves to the first side in the axial direction. As a result, the width of the groove between the fixed sheave 1 and the movable sheave 4 increases.

  In the pulley device on the driving side, when the width of the groove formed by the fixed sheave and the movable sheave increases, the winding diameter of the belt 120 decreases. That is, the belt 120 moves radially inward in the drive-side pulley device.

  When the belt 120 moves radially inward in the driving pulley device, the belt 120 moves radially outward in the driven pulley device 100. Then, the movable sheave 4 moves in a direction approaching the fixed sheave 1 by the urging force of the spring 90. As a result, the width of the groove between the fixed sheave 1 and the movable sheave 4 is reduced.

  Next, the operation of the cam mechanism 8 will be described. When the vehicle is suddenly accelerated, such as when starting, the movable sheave 4 rotates at a higher speed than the fixed sheave 1. Then, the movable boss 5 rotates at a higher speed than the spring seat 9. That is, the movable boss 5 rotates relative to the spring seat 9 in the rotation direction. Then, the cam mechanism 8 applies an axial thrust to the movable boss 5, and the movable boss 5 moves to the second side in the axial direction. Specifically, the cam surface 811 receives a reaction force from the cam receiving portion 82 to the second side in the axial direction, and the movable boss 5 moves to the second side in the axial direction. As a result, the movable sheave 4 moves toward the fixed sheave 1 and firmly clamps the belt 120.

[Modification]
Although the embodiments of the present invention have been described above, the present invention is not limited to these, and various modifications can be made without departing from the spirit of the present invention.

Modification 1
As shown in FIG. 11, the first seal member 7a may have a recess 77. The concave portion 77 is annular and extends in the circumferential direction on the inner peripheral surface of the first seal member 7a. The recess 77 is preferably formed at the axial center of the first seal member 7a. Similarly, the second seal member 7b may have a recess.

Modification 2
As shown in FIG. 12, in the first seal member 7a, the gap between the first end portion 71 and the second end portion 72 may be configured to increase as going outward in the radial direction. That is, the end faces of the first end 71 or the second end 72 may be inclined in a direction away from each other radially outward. The first seal member 7a is inserted, for example, to the first accommodation groove 54 in the movable boss 5 in a contracted state. When the first seal member 7a reaches the first storage groove 54, the first seal member 7a returns from the contracted state to the original state and is disposed in the first storage groove 54. When the first seal member 7a returns from the contracted state to the original state, the first end 71 and the second end 72 are less likely to be caught. Note that the second seal member 7b can have the same configuration.

Modification 3
The first and second seal members 7a and 7b may not have the first end 71 and the second end 72. That is, the first and second seal members 7a and 7b may be endless annular shapes.

Modification 4
Although the pulley device 100 according to the embodiment includes the cam mechanism 8, the pulley device 100 does not have to include the cam mechanism 8.

Modification 5
The fixed boss 2 may have a sliding layer formed of a material having a low coefficient of friction on the outer peripheral surface.

Modification 6
In the above embodiment, the first seal member 7a and the second seal member 7b have the same configuration, but only one of the seal members may have the above-described configuration.

1: fixed sheave 2: fixed boss 21: boss main body 22: inner flange portion 3: mounting member 31: mounting main body 311: screw portion 32: outer flange portion 92: flange portion 100: pulley device 101: drive plate 104: Nut member 110: first bearing member 111: retaining ring

Claims (6)

Fixed sheave,
A cylindrical boss body extending to the first side in the axial direction from the fixed sheave; and an inner flange portion extending radially inward from the first axial end of the boss body, and integrated with the fixed sheave. Fixed boss formed
A cylindrical mounting body protruding from the inside of the fixed boss to the first side in the axial direction and having a threaded portion formed on the outer peripheral surface; and a radially outer side extending from the second axial end of the mounting body to the inner side. An outer flange portion engaging with the flange portion, and a mounting member detachably and integrally rotatably mounted on the fixed boss;
A drive plate that rotates integrally with the fixed boss,
A nut member that is screwed with the screw portion of the mounting body portion and fastens the drive plate;
Equipped with a,
The mounting body has a pair of flat surfaces on an outer peripheral surface extending parallel to each other,
The pulley device , wherein the inner flange portion is engaged with the pair of flat surfaces .
The boss body further comprises a bearing member that sandwiches the outer flange portion with the inner flange portion,
The pulley device according to claim 1.
An outer peripheral surface of the bearing member contacts an inner peripheral surface of the boss body,
The pulley device according to claim 2.
Further comprising a retaining ring for restricting movement of the bearing member to the second side in the axial direction,
The pulley device according to claim 2.
The drive plate is attached to the attachment body.
The pulley device according to claim 1.
The drive plate engages the pair of flat surfaces;
The pulley device according to claim 1 .

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