JP6534593B2 - Pulley device - Google Patents

Description

  The present invention relates to a pulley apparatus.

  Belt-type continuously variable transmissions are employed in scooter-type motorcycles and the like. The continuously variable transmission includes a drive pulley device, a driven pulley device, and a belt. The belt is stretched between the drive and driven pulley devices.

  The driven pulley device clamps the belt by the movable sheave and the fixed sheave. At the time of rapid acceleration such as at the time of start-up, the moving sheaves rotate faster than the fixed sheave and rotate relative to each other, so the belt may not be held firmly by the moving sheave and the fixed sheave. In order to prevent this, the pulley apparatus of patent document 1 is provided with the cam mechanism. The cam mechanism is provided on the drive plate and the movable sheave boss. When the movable sheave rotates relative to the fixed sheave, the cam mechanism converts the rotation into axial thrust to move the movable sheave toward the fixed sheave. As a result, the belt is firmly clamped by the movable sheave and the fixed sheave.

Patent No. 3651628 gazette

  If the cam mechanism formed on the drive plate wears, it is necessary to replace the drive plate. The drive plate is a base member constituting a centrifugal clutch. Therefore, it is necessary to disassemble the centrifugal clutch portion in order to replace the drive plate, which makes the replacement operation difficult.

  An object of the present invention is to provide a pulley apparatus capable of easily performing replacement work when the cam mechanism is worn.

  A pulley apparatus according to a first aspect of the present invention includes a fixed sheave, a movable sheave, a movable sheave boss, a spring, a spring seat, and a cam mechanism. The movable sheave is movable so as to approach and move away from the stationary sheave in the axial direction. A movable sheave boss extends axially from the movable sheave. The spring axially biases the movable sheave towards the stationary sheave. The spring seat rotates integrally with the stationary sheave. The spring seat supports the spring. The cam mechanism is provided on the movable sheave boss and the spring seat. The cam mechanism is configured to convert the relative rotation of the movable sheave boss to the spring seat into the axial thrust of the movable sheave boss.

  According to this configuration, the cam mechanism is provided not on the drive plate but on the spring seat. Therefore, when the cam mechanism is worn out, the spring seat may be replaced instead of the drive plate. Here, unlike the drive plate, the spring seat is not a component of the centrifugal clutch. For this reason, when replacing the spring seat, there is no need to disassemble the centrifugal clutch, and the replacement operation can be easily performed.

  Preferably, the movable sheave boss has a cam portion that constitutes a cam mechanism. And preferably, a spring seat has a cylinder part, a flange part, and a cam receiving part. The cylindrical portion is disposed radially outward of the movable sheave boss and radially inward of the spring. The flange portion extends radially outward from the cylindrical portion and supports one end face of the spring. The cam receiving portion is disposed radially inward of the cylindrical portion. The cam receiving portion constitutes a cam mechanism and engages with the cam portion.

  Preferably, the spring seat is made of resin.

  Preferably, the pulley apparatus further comprises a drive plate that rotates integrally with the stationary sheave. The spring seat mates with the drive plate.

  According to the present invention, when the cam mechanism is worn, the replacement operation can be easily performed.

Side surface sectional drawing of a pulley apparatus. The top view of a spring seat. III-III sectional view taken on the line of FIG. Schematic for demonstrating the operation | movement of a cam mechanism. The top view of a drive plate. VI-VI sectional view taken on the line of FIG. The schematic for demonstrating the operation | movement of the cam mechanism which concerns on a modification.

  Hereinafter, embodiments of a pulley apparatus according to the present invention will be described with reference to the drawings. The pulley apparatus 100 according to the present embodiment is a driven pulley apparatus 100. A torque is transmitted to the driven pulley apparatus 100 from a drive pulley apparatus (not shown) via the belt 101. The belt 101 is a member for transmitting torque.

  FIG. 1 is a side sectional view of a pulley apparatus 100. FIG. In the following description, the rotation axis O means the rotation axis of the pulley device 100. The radial direction means the radial direction of a circle centered on the rotation axis O. The radially outer side means the side away from the rotation axis O in the radial direction, and the radially inner side means the side approaching the rotation axis O in the radial direction. The axial direction means a direction along the rotation axis O. The first axial side means the left side of FIG. 1, and the second axial side means the right side of FIG. The circumferential direction means the circumferential direction of a circle centered on the rotation axis O.

  As shown in FIG. 1, the pulley apparatus 100 includes a fixed sheave 1, a movable sheave 2, a fixed sheave boss 3, a movable sheave boss 4, a spring 5, a spring seat 6, and a cam mechanism 7; And a centrifugal clutch 8.

  The stationary sheave 1 is arranged to rotate around the rotation axis O. The central axis of the fixed sheave 1 is disposed substantially coaxially with the rotation axis O. The stationary sheave 1 is disposed on the second side of the movable sheave 2 in the axial direction. The stationary sheave 1 is fixed so as not to move in the axial direction.

  The stationary sheave 1 has a disk shape. The opposing surface 11 of the stationary sheave 1 is inclined away from the movable sheave 2 as it goes radially outward. That is, the opposing surface 11 is inclined toward the second side in the axial direction toward the outer side in the radial direction. The facing surface 11 of the fixed sheave 1 is a surface facing the movable sheave 2. That is, the opposing surface 11 of the stationary sheave 1 faces the first side in the axial direction.

  The stationary sheave boss 3 rotates integrally with the stationary sheave 1. In the present embodiment, the fixed sheave boss 3 and the fixed sheave 1 are formed by one member. The fixed sheave boss 3 and the fixed sheave 1 are respectively formed by separate members, and may be integrally rotated by being fixed to each other. The stationary sheave boss 3 is cylindrical and extends axially from the stationary sheave 1. In particular, the stationary sheave boss 3 extends axially from the stationary sheave 1 to the first side. The central axis of the fixed sheave boss 3 is disposed substantially coaxially with the rotation axis O.

  A centrifugal clutch 8 is attached to a first end 31 of the fixed sheave boss 3. The stationary sheave 1 extends radially outward from the second end 32 of the stationary sheave boss 3. The first end 31 is an end on the first side in the axial direction, and the second end 32 is an end on the second side in the axial direction. The first end portion 31 has mounting surfaces extending in parallel with one another on the outer peripheral surface. Since the first end 31 has a smaller outer diameter than the other portions, the shoulder 33 is formed.

  An output shaft (not shown) extends in the axial direction inside the fixed sheave boss 3. The output shaft is, for example, an shaft for transmitting torque to the rear wheels. The output shaft and the fixed sheave boss 3 rotate relative to each other. The bearings 102 and 103 are disposed between the output shaft and the fixed sheave boss 3.

  The movable sheave 2 is arranged to rotate around the rotation axis O. The central axis of the movable sheave 2 is disposed substantially coaxially with the rotation axis O. The movable sheave 2 is arranged to move along the rotation axis O. That is, the movable sheave 2 is arranged to move in the axial direction. The movable sheave 2 approaches and separates from the fixed sheave 1 by moving in the axial direction. The movable sheave 2 is disposed on the first side of the fixed sheave 1 in the axial direction.

  The movable sheave 2 has a disk shape. The opposing surface 21 of the movable sheave 2 is inclined away from the fixed sheave 1 as it goes radially outward. That is, the opposing surface 21 is inclined toward the first side in the axial direction toward the outer side in the radial direction.

  The facing surface 21 of the movable sheave 2 is a surface facing the fixed sheave 1. That is, the opposing surface 21 of the movable sheave 2 faces the second side in the axial direction. The opposing surface 11 of the fixed sheave 1 and the opposing surface 21 of the movable sheave 2 are opposed at an interval. A V groove is formed by the facing surface 11 of the fixed sheave 1 and the facing surface 21 of the movable sheave 2. By moving the movable sheave 2 in the axial direction, the groove width of the V groove changes. The belt 101 is disposed in the V-shaped groove. The belt 101 is held between the facing surface 11 of the fixed sheave 1 and the facing surface 21 of the movable sheave 2.

  The movable sheave 2 has an annular support wall 22 projecting to the first axial side. The support wall portion 22 is disposed radially outward of the movable sheave boss 4. The end of the spring 5 is disposed between the support wall 22 and the movable sheave boss 4.

  The movable sheave boss 4 rotates integrally with the movable sheave 2. Further, the movable sheave boss 4 axially moves integrally with the movable sheave 2. In the present embodiment, the movable sheave boss 4 and the movable sheave 2 are formed by one member. The movable sheave boss 4 and the movable sheave 2 are respectively formed by separate members, and may be integrally rotated and axially moved by being fixed to each other.

  The movable sheave boss 4 is cylindrical and extends axially from the movable sheave 2. In detail, the movable sheave boss 4 extends from the movable sheave 2 to the first axial side. That is, the movable sheave boss 4 extends away from the fixed sheave 1. The central axis of the movable sheave boss 4 is disposed substantially coaxially with the rotation axis O. The movable sheave boss 4 is disposed radially outside the fixed sheave boss 3. That is, the fixed sheave boss 3 extends in the movable sheave boss 4.

  The movable sheave boss 4 has a plurality of cam portions 41 at its end. The cam portions 41 are arranged at intervals in the circumferential direction. Each cam portion 41 extends on the first side in the axial direction. That is, each cam portion 41 is provided at the first end of the movable sheave boss 4 in the axial direction. Each cam portion 41 constitutes a cam mechanism 7.

  The movable sheave boss 4 can slide on the fixed sheave boss 3 without using any grease. The inner circumferential surface of the movable sheave boss 4 is in contact with the outer circumferential surface of the fixed sheave boss 3. In detail, the movable sheave boss 4 has a boss main body 42 and a resin portion 43. The boss main body 42 has a cylindrical shape. Each cam portion 41 extends from the boss main body 42 to a first side in the axial direction.

  The boss main body 42 is made of metal, for example. Specifically, the boss main body 42 is made of steel or an aluminum alloy. More specifically, the boss main body 42 is formed by at least one selected from the group consisting of carbon steel and alloy steel. The resin portion 43 is attached to the inner peripheral surface of the boss main body 42. A metal layer, a sintered body layer, or the like may be interposed between the boss main body 42 and the resin portion 43. The resin portion 43 has a cylindrical shape, and the inner peripheral surface of the resin portion 43 is in contact with the outer peripheral surface of the stationary sheave boss 3. The coefficient of friction of the resin portion 43 is smaller than the coefficient of friction of the boss main body 42. For example, the resin portion 43 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. As described above, since the resin portion 43 has a smaller coefficient of friction than the boss main body 42, the resin portion 43 can slide smoothly on the fixed sheave boss 3.

  The spring 5 biases the movable sheave 2 towards the stationary sheave 1 in the axial direction. That is, the spring 5 biases the movable sheave 2 toward the second side in the axial direction. By this, the fixed sheave 1 and the movable sheave 2 sandwich the belt 101. The spring 5 can be, for example, a coil spring. The spring 5 is disposed radially outward of the movable sheave boss 4 so as to surround the movable sheave boss 4.

  The spring seat 6 is configured to support the spring 5. As shown in FIGS. 2 and 3, the spring seat 6 has a cylindrical portion 61, a flange portion 62, and a plurality of cam receiving portions 63. The spring sheet 6 is made of, for example, a resin. Specifically, the spring sheet 6 is at least one selected from the group consisting of nylon resin, fluorocarbon resin, polyetheretherketone resin, and polyphenylene sulfide resin. The cylindrical portion 61, the flange portion 62, and the cam receiving portions 63 are integrally formed by one member.

  The cylindrical portion 61 is disposed radially outward of the movable sheave boss 4. Further, the cylindrical portion 61 is disposed on the inner side in the radial direction of the spring 5. That is, the cylindrical portion 61 is disposed between the movable sheave boss 4 and the spring 5 in the radial direction. The cylindrical portion 61 supports the spring 5 in the radial direction.

  The flange portion 62 extends radially outward from the cylindrical portion 61. Specifically, the flange portion 62 extends radially outward from the end portion of the cylindrical portion 61 on the first axial direction side. The flange portion 62 is annular. The flange portion 62 supports an end surface of the first side of the spring 5 in the axial direction. That is, the flange portion 62 supports the spring 5 in the axial direction.

  Each cam receiving portion 63 is disposed on the inner side in the radial direction of the cylindrical portion 61. In detail, each cam receiving portion 63 is formed on the inner peripheral surface of the cylindrical portion 61. Each cam receiving portion 63 extends in the circumferential direction. The cam receiving portions 63 are spaced apart from each other in the circumferential direction. The cam portion 41 extends between the cam receiving portions 63 adjacent in the circumferential direction. Each cam receiving portion 63 engages with each cam portion 41 of the movable sheave boss 4. Each cam receiving portion 63 constitutes a cam mechanism 7. Each cam receiving portion 63 has a recess 631. The recess 631 extends in the radial direction. The recess 631 accommodates part of a drive plate 81 described later.

  The spring seat 6 rotates integrally with the fixed sheave 1. In more detail, the spring seat 6 has a projection 64 projecting to the first axial side. The projection 64 fits in a through hole 814 (see FIG. 5) of the drive plate 81 described later. The protrusion 64 is shaped along the outer peripheral edge of the through hole 814. The drive plate 81 rotates integrally with the stationary sheave 1 via the stationary sheave boss 3. Therefore, the spring seat 6 attached to the drive plate 81 rotates integrally with the fixed sheave 1.

  As shown in FIG. 1, the cam mechanism 7 is provided on the movable sheave boss 4 and the spring seat 6. In detail, the cam mechanism 7 is composed of a plurality of cam portions 41 and a plurality of cam receiving portions 63. The cam mechanism 7 is configured to convert relative rotation of the movable sheave boss 4 with respect to the spring seat 6 into axial thrust of the movable sheave boss 4. That is, when the movable sheave boss 4 rotates at a higher speed than the spring seat 6, the cam mechanism 7 moves the movable sheave boss 4 toward the fixed sheave 1.

  In detail, as shown in FIG. 4, each cam portion 41 of the movable sheave boss 4 has a cam surface 411. The cam surface 411 is inclined so as to face the rotational direction and to face the first side in the axial direction. The cam surface 411 abuts on the cam receiving portion 63 of the spring seat 6. The rotational direction is the direction in which the movable sheave boss 4 rotates when the vehicle advances.

  As shown in FIG. 1, the centrifugal clutch 8 has a drive plate 81, a plurality of clutch shoes 82, and a clutch housing 83. The centrifugal clutch 8 is configured to transmit and interrupt the rotation of the fixed sheave 1 and the movable sheave 2 to and from the output shaft. In detail, the centrifugal clutch 8 is configured to transmit and interrupt the rotation of the fixed sheave boss 3 to the output shaft.

  The drive plate 81 is attached to the first end 31 of the stationary sheave boss 3. The drive plate 81 rotates integrally with the stationary sheave boss 3. As shown in FIGS. 5 and 6, the drive plate 81 has a boss portion 811 and a disc portion 812.

  The bosses 811 are cylindrical and extend in the axial direction. The boss portion 811 is attached to the fixed sheave boss 3. In detail, the boss portion 811 has a through hole 813 at the center. The through hole 813 is shaped to engage with the first end 31 of the stationary sheave boss 3. Specifically, the outer peripheral edge of the through hole 813 has substantially the same shape as the outer peripheral edge of the stationary sheave boss 3.

  The disc portion 812 extends radially outward from the boss portion 811. The disk portion 812 is flat. That is, the disk portion 812 substantially does not have a stepped portion. In addition, the disc part 812 may not be flat form, and may have a level | step-difference part. The disk portion 812 has a plurality of through holes 814. Each through hole 814 penetrates in the axial direction. Each through hole 814 extends in the circumferential direction. The through holes 814 are spaced apart in the circumferential direction. The protruding portion 65 of the above-described spring seat 6 is fitted into the through hole 814. Further, each cam portion 41 of the movable sheave boss 4 described above extends in the through hole 814 so as not to interfere with the disc portion 812. A part of the disk portion 812 disposed between the adjacent through holes 814 is accommodated in the recess 631 of the cam receiving portion 63 described above.

  The drive plate 81 is made of metal. Specifically, the drive plate 81 is made of steel or aluminum alloy. More specifically, the drive plate 81 is at least one selected from the group consisting of carbon steel and alloy steel. Movement of the drive plate 81 in the axial direction to the second side is restricted by abutting on the shoulder 33 of the stationary sheave boss 3. Further, the retaining ring 90 attached to the first end 31 regulates the movement of the drive plate 81 to the first side in the axial direction.

  As shown in FIG. 1, each clutch shoe 82 is swingably attached to a drive plate 81 at one end in the circumferential direction. Each clutch shoe 82 has a friction material 84 on its outer peripheral surface. A return spring (not shown) is attached to the other end of each clutch shoe 82 so as to bias each clutch shoe 82 radially inward.

  The clutch housing 83 is disposed so as to cover each clutch shoe 82 from the outside in the radial direction. The clutch housing 83 is relatively rotatably supported by the stationary sheave boss 3. In detail, the clutch housing 83 has a boss 831. Spline holes 8311 are formed in the boss portion 831. The output shaft can be splined in this spline hole 8311.

  When the centrifugal clutch 8 is in the transmission state, the friction material 84 of each clutch shoe 82 frictionally engages with the inner circumferential surface of the clutch housing 83. Further, when the centrifugal clutch 8 is in the disengaged state, the friction material 84 of each clutch shoe 82 is separated from the inner circumferential surface of the clutch housing 83. The transmission state of the centrifugal clutch 8 means that the centrifugal clutch 8 transmits the rotation of the fixed sheave 1 and the movable sheave 2 to the output shaft. The disengagement state of the centrifugal clutch 8 means that the centrifugal clutch 8 does not transmit the rotation of the fixed sheave 1 and the movable sheave 2 to the output shaft.

  The pulley apparatus configured as described above operates as follows.

  In the pulley apparatus on the drive side, when the width of the groove formed by the fixed sheave and the movable sheave is narrowed, the winding diameter of the belt 101 is increased. That is, the belt 101 moves radially outward in the driving pulley apparatus.

  As shown in FIG. 1, in the pulley apparatus 100 on the driven side, the width of the groove formed by the fixed sheave 1 and the movable sheave 2 operates reverse to the groove width in the pulley apparatus on the drive side. That is, when the belt 101 moves outward in the radial direction in the drive-side pulley device, the belt 101 moves inward in the radial direction in the driven-side pulley device 100.

  When the belt 101 moves inward in the radial direction, the movable sheave 2 moves away from the fixed sheave 1 against the biasing force of the spring 5. That is, the movable sheave 2 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 2 is increased.

  Further, in the pulley apparatus on the drive side, when the width of the groove constituted by the fixed sheave and the movable sheave is expanded, the winding diameter of the belt 101 is reduced. That is, the belt 101 moves radially inward in the pulley apparatus on the drive side.

  When the belt 101 moves inward in the radial direction in the drive-side pulley device, the belt 101 moves outward in the radial direction in the driven-side pulley device 100. Then, due to the biasing force of the spring 5, the movable sheave 2 moves in the direction approaching the fixed sheave 1. As a result, the width of the groove between the fixed sheave 1 and the movable sheave 2 is narrowed.

  Next, the operation of the cam mechanism 7 will be described. When accelerating rapidly as at the time of start, the movable sheave 2 rotates at a higher speed than the fixed sheave 1. Then, as shown in FIG. 4, the movable sheave boss 4 rotates at a speed faster than that of the spring seat 6. That is, the movable sheave boss 4 rotates relative to the spring seat 6 in the rotational direction. Then, the cam mechanism 7 applies axial thrust to the movable sheave boss 4, and the movable sheave boss 4 moves to the second axial side. Specifically, the cam surface 411 receives the reaction force from the cam receiving portion 63 in the axial direction to the second side, and the movable sheave boss 4 moves in the axial second direction. As a result, the movable sheave 2 moves to the fixed sheave 1 side and holds the belt 101 firmly.

  As mentioned above, the pulley apparatus 100 which concerns on this embodiment has the following characteristics.

  The cam mechanism 7 is provided not on the drive plate 81 but on the spring seat 6. Therefore, when the cam mechanism 7 is worn, particularly when the cam receiving portion 63 is worn, the spring sheet 6 may be replaced instead of the drive plate 81. Here, unlike the drive plate 81, the spring seat 6 is not a component of the centrifugal clutch 8. For this reason, when replacing the spring seat 6, there is no need to disassemble the centrifugal clutch 8, and the replacement operation can be performed easily.

[Modification]
As mentioned above, although embodiment of this invention was described, this invention is not limited to these, A various change is possible unless it deviates from the meaning of this invention.

Modification 1
Although each cam portion 41 has the cam surface 411 in the above embodiment, the cam receiving portion 63 may have the cam surface. For example, as shown in FIG. 7, the cam receiving portion 63 of the spring seat 6 has a cam surface 631. The cam surface 631 is inclined to face the second side in the axial direction while facing in the direction opposite to the rotational direction. In this case, in order to improve the strength of the cam receiving portion 63 of the spring seat 6, a reinforcing member such as metal may be embedded inside the cam receiving portion 63.

Modification 2
In the above embodiment, the movable sheave boss 4 slides on the fixed sheave boss 3 without using grease, but may slide on the fixed sheave boss 3 via grease.

Modification 3
In the above embodiment, the boss portion 811 protrudes in the axial direction from the disc portion 812, but the boss portion 811 may not protrude from the disc portion 812. That is, there may be no stepped portion at the boundary between the boss portion 811 and the disc portion 812, and the boss portion 811 may be constituted by the inner peripheral end portion of the disc portion 812.

Modification 4
In the above embodiment, the bosses 811 have a cylindrical shape, but the shape of the bosses 811 is not particularly limited. For example, the boss portion 811 may be a polygonal tubular member. Further, the through hole 813 of the boss portion 811 may be a spline hole.

1: Fixed sheave 2: Moveable sheave 4: Boss for moveable sheave 5: Spring 6: Spring seat 7: Cam mechanism 41: Cam part 61: Cylindrical part 62: Flange part 63: Cam receiving part 81: Drive plate 100: Pulley device

Claims (4)

Fixed sheaves,
A movable sheave movable in axial direction toward and away from the fixed sheave;
A movable sheave boss axially extending from the movable sheave;
A spring biasing the movable sheave towards the stationary sheave in an axial direction;
A spring seat that rotates integrally with the fixed sheave and supports the spring;
A cam mechanism provided on the movable sheave boss and the spring seat, configured to convert relative rotation of the movable sheave boss with respect to the spring seat into an axial thrust of the movable sheave boss;
A drive plate integrally rotating with the fixed sheave;
Bei to give a,
The spring seat engages with the drive plate.
Pulley device.
The movable sheave boss has a cam portion constituting the cam mechanism,
The spring seat is
A cylindrical portion disposed radially outward of the movable sheave boss and radially inward of the spring;
A flange portion extending radially outward from the cylindrical portion and supporting one end face of the spring;
A cam receiving portion disposed radially inward of the cylindrical portion, constituting a cam mechanism, and engaged with the cam portion;
Have
The pulley apparatus according to claim 1.
The spring seat is made of resin.
The pulley apparatus of Claim 1 or 2.
  Fixed sheaves,
  A movable sheave movable in axial direction toward and away from the fixed sheave;
  A movable sheave boss axially extending from the movable sheave;
  A spring biasing the movable sheave towards the stationary sheave in an axial direction;
  A spring seat that rotates integrally with the fixed sheave and supports the spring;
  A cam mechanism provided on the movable sheave boss and the spring seat, configured to convert relative rotation of the movable sheave boss with respect to the spring seat into an axial thrust of the movable sheave boss;
Equipped with
  The movable sheave boss has a cam portion constituting the cam mechanism,
  The spring seat is
    A cylindrical portion disposed radially outward of the movable sheave boss and radially inward of the spring;
    A flange portion extending radially outward from the cylindrical portion and supporting one end face of the spring;
    A cam receiving portion disposed radially inward of the cylindrical portion, constituting a cam mechanism, and engaged with the cam portion;
Have
Pulley device.

Images