JP4604059B2 - Driving force transmission pulley and method of manufacturing the same - Google Patents

Description

  The present invention relates to a driving force transmission pulley capable of suspending an endless belt so as to transmit a driving force of a vehicle, and a method for manufacturing the pulley.

  As shown in FIG. 8, a centrifugal clutch generally employed in a scooter type motorcycle includes a driven pulley 101 that suspends a V-belt from a driving pulley (not shown) that rotates by driving an engine, and the driven pulley. A drive plate 104 connected to the pulley 101, a clutch member 105 formed on the outer peripheral surface of the drive plate 104 and movable laterally by centrifugal force during rotation, and a clutch member 105 moved laterally And an output housing 106 that rotates together with the drive plate 104, and a shaft 107 that extends from the center of the output housing 106 and is connected to the rear wheel of the vehicle via a speed reducer.

  Of these, the driven pulley 101 (driving force transmission pulley) includes a fixed sheave 102 having a fixed taper surface 102a and a movable side facing the fixed taper surface 102a of the fixed sheave 102, as shown in FIG. It has a tapered surface 103a and is rotatable with the fixed sheave 102 while suspending an endless belt (V-belt) between the fixed side tapered surface 102a and the movable side tapered surface 103a. The movable sheave 103 is mainly composed of a movable sheave 103 that can be moved toward or away from the movable sheave 103, and the shift of the vehicle is performed by moving the movable sheave 103 toward or away from the fixed sheave 102.

  As shown in FIG. 9, the fixed sheave 102 (same as the movable sheave 103) has one end of a cylindrical shaft member 108 welded thereto, and is rotatable about the shaft member 108 as an axis. However, conventionally, the end portion of the shaft member 108 is burring and raised into an annular shape to form the burring portion 108a, and the opening edge of the fixed sheave 102 corresponding thereto is also burring and standing in an annular shape. The burring portion 102b was formed by raising the burring portions 108a and 102b, and the protruding ends of the burring portions 108a and 102b were welded by plasma welding or Tig welding.

  Here, in the same figure, the symbol α indicates the welded portion between the burring portions 108a and 102b, and the welded portion is formed in an annular shape. That is, an annular welding portion is formed by operating the welding torch in an annular shape along the protruding ends of the burring portions 108a and 102b. In addition, since this prior art does not relate to the literature known invention, there is no prior art document information to be described.

  However, in the conventional driving force transmission pulley, the fixed sheave 102 and the shaft member 108 are welded by plasma welding to the protruding ends of the burring portions 102b and 108a formed, respectively, so that the burring portions 108a and 102b There is a problem that the welding torch needs to be operated in an annular shape along the tip, and a long time is required for the welding operation, resulting in an increase in cycle time. Therefore, if a long time is required for the welding operation, heat input to the fixed sheave 102 becomes excessive, and there is a possibility that the fixed side tapered surface 102a is distorted, for example.

  Further, since it is necessary to form burring portions 102b and 108a on the fixed sheave 102 and the shaft member 108, respectively, and to weld them together, the burring portions 102b and 108a are bent or broken at the time of abutment. Therefore, there is a possibility that welding by plasma welding cannot be performed satisfactorily. Such a problem may occur not only in welding the fixed sheave and the shaft member but also in welding the movable sheave and the shaft member.

  The present invention has been made in view of such circumstances, and allows the fixed sheave or the movable sheave and the shaft member to be welded in a short time and well, shortening the cycle time during manufacture and improving the assembling accuracy. An object of the present invention is to provide a driving force transmission pulley that can be realized and a method for manufacturing the pulley.

The invention according to claim 1 has a fixed sheave formed with a fixed taper surface, and a movable taper surface facing the fixed taper surface of the fixed sheave, the fixed taper surface and the movable taper surface A movable sheave that is rotatable with the fixed sheave while suspending an endless belt between the movable sheave and a circular opening substantially in the center of the fixed sheave and the movable sheave. The opening edge of the fixed sheave and the movable sheave is welded to the opening in which the opening edge is parallel and linear to the rotation axis direction and the opening of the fixed sheave and the movable sheave. and a hollow shaft member with the cylindrical forming the shaft, the driving force transmission pulley for transmitting a driving force of the vehicle, at least one of the fixed sheave or movable sheave of said shaft member The wear part, together with the protruding end outer peripheral surface bulges from the outer peripheral surface of the shaft member in a radial direction thick portion that is parallel and straight with respect to the axial direction is formed, the said thick portion An electric resistance welding is carried out by energizing between the opening edge while being pressed into the opening, and the shaft member is welded to the fixed sheave or the movable sheave. After the welding, the shaft member is fixed to the fixed sheave or the movable sheave. The welding surface of the welded portion with the sheave is inclined with respect to the press-fitting direction.

  According to a second aspect of the present invention, in the driving force transmission pulley according to the first aspect, the fixed sheave or the movable sheave has a welding site with the shaft member in the vicinity of the rotating shaft direction of the fixed sheave or the movable sheave. A step portion formed by bending is formed.

  According to a third aspect of the present invention, in the driving force transmitting pulley according to the first or second aspect, a direction opposite to a direction in which a load is applied from the endless belt to the fixed-side tapered surface or the movable-side tapered surface. The thick portion is press-fitted into the opening in a direction.

According to a fourth aspect of the present invention, there is provided a fixed sheave having a fixed-side tapered surface, and a movable-side tapered surface facing the fixed-side tapered surface of the fixed sheave, the fixed-side tapered surface and the movable-side tapered surface A movable sheave that is rotatable with the fixed sheave while suspending an endless belt between the movable sheave and a circular opening substantially in the center of the fixed sheave and the movable sheave. The opening edge of the fixed sheave and the movable sheave is welded to the opening in which the opening edge is parallel and linear to the rotation axis direction and the opening of the fixed sheave and the movable sheave. and a hollow shaft member with the cylindrical forming the shaft, the driving force method of manufacturing a transmission pulley for transmitting a driving force of the vehicle less the fixed sheave or movable sheave of said shaft member Together in the one of the welding site, the thick portion of the protruding end outer peripheral surface bulged in the radial direction from the outer peripheral surface is parallel and straight with respect to the axial direction of the shaft member is formed, the thick An electric resistance welding is carried out by energizing between the opening edge portion while pressing the portion into the opening portion, and the shaft member is welded to the fixed sheave or the movable sheave and fixed to the shaft member after welding. The welding surface of the welding portion with the sheave or the movable sheave is inclined with respect to the press-fitting direction.

  According to a fifth aspect of the present invention, in the method for manufacturing a driving force transmitting pulley according to the fourth aspect, the fixed sheave or the movable sheave is rotated in the vicinity of the welding portion with the shaft member in the fixed sheave or the movable sheave. A step portion formed by bending in the axial direction is formed.

  According to a sixth aspect of the present invention, in the method for manufacturing a driving force transmitting pulley according to the fourth or fifth aspect, a load is applied from the endless belt to the fixed-side tapered surface or the movable-side tapered surface. The thick portion is press-fitted into the opening in a direction opposite to the direction.

  According to the first and fourth aspects of the present invention, an annular electric resistance welding is performed by energizing the thick part of the shaft member between the opening edge of the fixed sheave or the movable sheave while being pressed into the opening. In addition, since the shaft member is welded to the fixed sheave or the movable sheave, the fixed sheave or the movable sheave and the shaft member can be welded in a short time and well, shortening the cycle time during manufacture and improving the assembly accuracy. Can be planned.

  According to invention of Claim 2 and Claim 5, the step part formed by bending in the rotation-axis direction of the said fixed sheave or a movable sheave is formed in the vicinity of the welding part with the shaft member in a fixed sheave or a movable sheave. Therefore, even when an axial load is applied to the fixed or movable side taper surface of the fixed sheave or movable sheave during operation of the driving force transmission pulley, the load is received by the stepped portion. Can do. Therefore, when an axial load is applied, it is possible to avoid stress concentration on the welded portion between the fixed sheave and the shaft member, and the strength and durability can be improved.

  According to the third and sixth aspects of the invention, the thick-walled opening is press-fitted in the direction opposite to the direction in which the load is applied from the endless belt to the fixed-side tapered surface or the movable-side tapered surface. Therefore, the welded part can sufficiently resist the load applied from the endless belt, and a higher-strength driving force transmission pulley can be obtained.

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.
The driving force transmission pulley according to this embodiment is applied to a driven pulley of a centrifugal clutch device in a scooter type motorcycle. Such a centrifugal clutch device is for transmitting and interrupting engine driving force in a scooter type motorcycle. As shown in FIG. 1, a driven pulley 1, a drive plate 4, a clutch member 7, and an output It is mainly composed of a housing 6 and a shaft 7.

  The driven pulley 1 is configured such that a resin V belt 10 (endless belt) can be suspended between a driven pulley (not shown) that is rotated by driving a motorcycle engine. The driven pulley 1 is composed of a fixed sheave 2 and a movable sheave 3 made of a metal molded product, and a taper surface (fixed side taper surface 2a and movable side taper surface 3a) is formed at a space between the fixed sheave 2 and the movable sheave 3. Is formed. The V belt 10 is fitted into these opposing tapered surfaces, and the V belt 10 is suspended between the drive pulleys.

  A cylindrical shaft member 8 protrudes from the substantially center of the fixed sheave 2, and a needle bearing B1 and a ball bearing B2 are disposed on the inner peripheral surface 8b of the shaft member 8 to rotate the shaft 7. It can be inserted freely. A movable sheave 3 is assembled on the outer periphery of the fixed sheave 2 by spline fitting. Both sheaves can be rotated along with the rotation of the V-belt 10, and the movable sheave 3 can be moved closer to or away from the fixed sheave 2. It is said that.

  Specifically, the movable sheave 3 is constantly urged by the spring SP in the direction approaching the fixed sheave 2 (that is, the direction in which the fixed taper surface and the movable taper surface are close to each other), and the driven pulley. When the diameter-reducing operation of the V-belt 10 in 1 is applied, the V-belt 10 can move in a direction away from the fixed sheave 2 (left direction in the figure) against the urging force of the spring SP. As with the fixed sheave 2, a cylindrical shaft member 9 is formed on the movable sheave 3 so as to protrude from substantially the center thereof, and the shaft member 8 of the fixed sheave 2 extends along the inner peripheral surface 9 b of the shaft member 9. Can slide.

  Accordingly, when the rotational speed of the engine is increased, the fitting portion of the V-belt 10 on the drive pulley side is narrowed and the diameter thereof is widened. In response to this action, the movable sheave 3 moves to the left (in the direction in which the diameter of the fitting portion of the V-belt 10 decreases) and shifts up. As described above, the centrifugal clutch device of the present embodiment is configured such that a shift change is automatically made according to the vehicle speed.

  The drive plate 4 is connected to the fixed sheave 2 of the driven pulley 1 and can rotate together with the driven pulley 1. The outer peripheral surface of the drive plate 4 is a clutch made of a friction material movable in the radial direction (the vertical direction in the figure). A member 5 and a weight 11 are provided. That is, when the number of rotations of the driven pulley 1 exceeds a predetermined value, the clutch member 5 moves in the direction of expanding the diameter by the centrifugal force, and can contact the inner peripheral surface of the flange portion of the output housing 6 so that the output The housing 6 is rotated around.

  The output housing 6 is formed in an umbrella shape having an insertion hole 6a formed substantially at the center and covering the outer peripheral surface of the drive plate 4. The tip of the shaft 7 is inserted into the insertion hole 6a. It is configured to be able to. Further, a cylindrical member 6b extending toward the driven pulley 1 is integrally formed (for example, fixed by welding or the like) from the peripheral edge of the inner peripheral surface of the insertion hole 6a, and formed on the inner peripheral surface of the cylindrical member 6b. The assembled spline is assembled so as to mesh with a spline formed on the shaft 7 side.

  The tip of the shaft 7 is connected to the output housing 6 by a tightening nut N and can rotate with the output housing 6. A reduction gear (configured by a reduction gear or the like) (not shown) is connected to the base end side of the shaft 7 so that the rear wheels of the motorcycle can be driven. That is, when the driven pulley 1 reaches a predetermined number of revolutions, the clutch member 5 comes into contact with the output housing 6 by the centrifugal force, and the rotational force of the driven pulley 1 and the drive plate 4 passes through the output housing 6. And transmitted to the shaft 7 to drive the rear wheels of the motorcycle.

  Here, as shown in FIGS. 2 to 4, the fixed sheave 2 in the present embodiment has an opening A formed in a circular shape at the substantially center thereof, and the cylindrical shaft member 8 is formed in the opening A. The shaft member 8 protrudes from the fixed sheave 2 by welding one end thereof. Thus, the fixed sheave 2 is rotatable about the shaft member 8 as a rotation shaft in a state where the fixed sheave 2 is assembled to the driven pulley 1 (pulley for driving force transmission).

  More specifically, a thick portion 8a formed by bulging in the radial direction from the outer peripheral surface of the shaft member 8 is formed at a welded portion of the shaft member 8 with the fixed sheave 2 (portion indicated by β in FIG. 2). The thick member 8a is pressed into the opening A of the fixed sheave 2 and energized between the opening edges of the fixed sheave 2 to weld the shaft member 8 to the fixed sheave 2. Welding. That is, the inner diameter dimension t1 of the opening A of the fixed sheave 2 is set to be slightly smaller than the outer diameter dimension t2 of the thick wall portion 8a, and the opening A is thickened by an annular electric resistance welding apparatus described later. The meat part 8a is welded by being energized while being press-fitted.

  As a result, the fixed sheave 2 and the shaft member 8 can be welded in a shorter time and better than the conventional plasma welding or Tig welding using a welding torch, shortening the cycle time during manufacture and assembling accuracy. Can be improved. That is, according to the annular electric resistance welding as in the present embodiment, the welding work is shorter in comparison with the plasma welding, and the fixed sheave 2 and the shaft member 8 are reduced while suppressing the distortion by reducing the heat input. Welding can be performed.

  In particular, since the fixed sheave 2 is welded to the thick portion 8a of the shaft member 8, the shaft member 8 bends inward when the fixed sheave 2 and the shaft member 8 are welded, and the dimension of the inner peripheral surface 8b is reduced. It can avoid becoming small and can maintain the arrangement | positioning operation | work of bearing B1 (refer FIG. 1) favorably. Further, since it is not necessary to form a burring portion before welding as in the prior art, the welding operation can be performed better, and the manufacturing process of the driven pulley 1 (driving force transmission pulley) can be simplified. .

  Further, in the present embodiment, a step portion 2b formed by bending in the direction of the rotation axis of the fixed sheave 2 (vertical direction in FIG. 2) is formed in the vicinity of the welding site β with the shaft member 8 in the fixed sheave 2. Is formed. As a result, even when an axial load is applied to the fixed-side tapered surface 2a of the fixed sheave 2 during operation of the driven pulley 1 (driving force transmission pulley), the load can be received by the stepped portion 2b. it can. Therefore, when an axial load is applied, it is possible to avoid stress concentration on the welded portion β between the fixed sheave 2 and the shaft member 8, and strength and durability can be improved.

  In the above description, the fixed sheave 2 and the shaft member 8 have been described. However, in the present embodiment, the same applies to the movable sheave 3 and the shaft member 9. That is, a thick portion 9a (see FIG. 1) bulging from the outer peripheral surface of the shaft member 9 in the radial direction is formed at the welded portion of the shaft member 9 with the movable sheave 3, and the thick portion 9a is pressed into the opening of the movable sheave 3 (opening in the same manner as the opening A of the fixed sheave 2) and energized between the edges of the opening to fix the shaft member 9 It is welded to the sheave 3.

Next, the welding method with the shaft member 8 of the fixed sheave 2 according to the present embodiment will be described.
The welding operation between the fixed sheave 2 and the shaft member 8 is performed using an annular electric resistance welding apparatus as shown in FIG. Such an annular electric resistance welding apparatus includes an upper electrode member 12 made of a conductor having a protruding end (lower end in the figure) formed in a ring shape, a movable mold 13 made of a conductor connected to the pressing body 12, and The upper pad member 16 that can abut along the fixed tapered surface 2 a of the fixed sheave 2, the shaft member 8 can be placed, and the lower electrode member 14 made of a conductor is connected to the lower electrode member 14. The fixed die 15 made of a conductive material and the lower pad member 17 capable of contacting along the surface opposite to the fixed taper surface 2a of the fixed sheave 2 are mainly constituted.

  The upper electrode member 12, the movable mold 13, the lower electrode member 14, and the fixed mold 15 are made of a good conductor such as chrome copper, and the upper pad member 16 and the lower pad member 17 are made of a nonmagnetic insulator. is there. Then, as shown on the left side of FIG. 5, if the fixed sheave 2 is placed on the lower pad 17 and the upper pad 16 is held in contact with the fixed taper surface 2a, an annular electric resistance welding apparatus is provided. The fixed sheave 2 can be fixed inside.

  On the other hand, as shown on the left side of the figure, on the lower electrode member 14, the shaft member 8 with the welded portion turned upside down is placed, and the protruding end of the upper electrode member 12 is opened in the fixed sheave 2. It is made to contact the upper opening edge of the part A. From this state, the movable mold 13 is moved in the direction of approaching the fixed mold 15 and lowered with the upper electrode member 12, and at the same time, a voltage is applied between the movable mold 13 and the fixed mold 15.

  Thus, the thick portion 8a of the shaft member 8 is welded by being energized between the opening edge portion while being pressed into the opening portion A, and annular electric resistance welding is performed. As a result, as shown on the right side of the figure, the fixed sheave 2 can be obtained in which the shaft member 8 is welded in a protruding state at the approximate center, so that the movable die 13 is raised together with the upper electrode member 12 to If 16 is also raised, the fixed sheave 2 to which the shaft member 8 is welded can be taken out.

  The movable sheave 3 and its shaft member 9 can also be welded by the annular electric resistance welding apparatus. Further, in the present embodiment, the upper electrode member 12 is lowered to operate the fixed sheave 2 on the fixed shaft member 8 to perform annular electric resistance welding. Alternatively, the shaft member 8 may be operated with respect to 2, and an annular electric resistance welding may be performed.

  Here, in this embodiment, since the press-fitting is performed in the direction as shown in FIG. 6, a higher-strength driving force transmission pulley (driven pulley 1) can be obtained. That is, as shown in the figure, in the state assembled as the driven pulley 1, the direction a opposite to the direction a in which a load is applied from the endless belt 10 to the fixed taper surface 2a (or the movable taper surface 3a in the movable sheave 3). When the thick portion 8a (the thick portion 9a) is press-fitted into the opening A in the direction b, the welding surface γ of the welding portion β is inclined as shown in FIG.

  Thus, since the welding surface γ of the welding site β by press fitting is inclined so as to rise upward with respect to that direction even when a load in the direction a is applied to the fixed sheave 2, the pulley for driving force transmission When the (driven pulley 1) is used, even if a load is applied from the endless belt 10 to the fixed side taper surface 2a in the direction a, the load can be sufficiently resisted, and a higher-strength driving force transmission pulley Can be obtained.

  Although the present embodiment has been described above, the present invention is not limited to this. For example, as long as it is a driving force transmission pulley capable of suspending an endless belt, other forms of pulleys (of this embodiment) Such a scooter type motorcycle may be applied to a different form). Further, the fixed sheave 2 in the present embodiment has the step 2b, but the step 2b may not be formed, or the movable sheave 3 is formed with a step similar to the step 2b. You may do it.

  A thick-walled portion that bulges in the radial direction from the outer peripheral surface of the shaft member is formed at the welding portion of the shaft member with the fixed sheave or the movable sheave, and the thick-walled portion is press-fitted into the opening while A driving force transmission pulley formed by welding an annular electric resistance between the opening edge and welding the shaft member to a fixed sheave or a movable sheave, and its manufacturing method are different in appearance. Or it can apply also to what added another function.

1 is a schematic cross-sectional view showing a centrifugal clutch device to which a driving force transmission pulley according to an embodiment of the present invention is applied. A plan view and a front view showing a fixed sheave and its shaft member in the driving force transmission pulley Sectional view showing fixed sheave in pulley for power transmission A longitudinal sectional view showing a shaft member in the power transmission pulley It is a schematic diagram showing an annular electric resistance welding device for welding the shaft member of the power transmission pulley to the fixed sheave, the left side is a state before welding and the right side is a state after welding Schematic diagram for showing the press-fitting direction when welding the shaft member of the power transmission pulley to the fixed sheave The schematic diagram which shows the state after welding the shaft member of the pulley for power transmission to a fixed sheave Sectional schematic diagram showing a centrifugal clutch device to which a conventional pulley for driving force transmission is applied Sectional schematic diagram showing a conventional fixed sheave and its shaft member

Explanation of symbols

1 Driven pulley (drive force transmission pulley)
DESCRIPTION OF SYMBOLS 2 Fixed sheave 3 Movable sheave 4 Drive plate 5 Clutch member 6 Output housing 7 Shaft 8 Shaft member 8a Thick part 9 Shaft member 10 Endless belt 11 Weight 12 Upper electrode member 13 Movable type 14 Lower electrode member 15 Fixed type 16 Upper pad member 17 Lower pad member A Opening

Claims (6)

A fixed sheave having a fixed-side tapered surface;
The movable sheave has a movable taper surface facing the fixed taper surface of the fixed sheave, and is rotatable with the fixed sheave while suspending an endless belt between the fixed taper surface and the movable taper surface. A movable sheave that can be moved close to or away from the fixed sheave;
An opening having a circular opening at substantially the center of the fixed sheave and the movable sheave, and an opening edge thereof being parallel and linear to the rotation axis direction;
A cylindrical and hollow shaft member welded to the openings of the fixed sheave and the movable sheave and projecting from each to form the rotation shaft of the fixed sheave and the movable sheave;
In the driving force transmission pulley for transmitting the driving force of the vehicle,
At least one welded portion of the shaft member with the fixed sheave or the movable sheave has a thickness that bulges in the radial direction from the outer peripheral surface of the shaft member, and the protruding outer peripheral surface is parallel and linear to the axial direction. A thick portion is formed, and an annular electric resistance welding is performed by energizing the thick portion with the opening edge while press-fitting the thick portion into the opening, and the shaft member is attached to the fixed sheave or the movable sheave. A pulley for driving force transmission, wherein a welding surface of a welding portion between the shaft member and the fixed sheave or the movable sheave after welding is inclined with respect to the press-fitting direction.   2. A step portion formed by bending the fixed sheave or the movable sheave in the direction of the rotation axis of the fixed sheave or the movable sheave is formed in the vicinity of a welding portion with the shaft member. Drive force transmission pulley.   2. The press-fitting of the thick portion into the opening in a direction opposite to a direction in which a load is applied from the endless belt to the fixed-side tapered surface or the movable-side tapered surface. The pulley for driving force transmission according to claim 1 or 2. A fixed sheave having a fixed-side tapered surface;
The movable sheave has a movable taper surface facing the fixed taper surface of the fixed sheave, and is rotatable with the fixed sheave while suspending an endless belt between the fixed taper surface and the movable taper surface. A movable sheave that can be moved close to or away from the fixed sheave;
An opening having a circular opening at substantially the center of the fixed sheave and the movable sheave, and an opening edge thereof being parallel and linear to the rotation axis direction;
A cylindrical and hollow shaft member welded to the openings of the fixed sheave and the movable sheave and projecting from each to form the rotation shaft of the fixed sheave and the movable sheave;
In the manufacturing method of the driving force transmission pulley for transmitting the driving force of the vehicle,
At least one welded portion of the shaft member with the fixed sheave or the movable sheave has a thickness that bulges in the radial direction from the outer peripheral surface of the shaft member, and the protruding outer peripheral surface is parallel and linear to the axial direction. A thick portion is formed, and an annular electric resistance welding is performed by energizing the thick portion with the opening edge while press-fitting the thick portion into the opening, and the shaft member is attached to the fixed sheave or the movable sheave. A method for manufacturing a driving force transmission pulley, characterized by welding, and inclining a welding surface of a welding portion between the shaft member and a fixed sheave or a movable sheave after welding with respect to a press-fitting direction.   5. A step portion formed by bending in the direction of the rotation axis of the fixed sheave or the movable sheave is formed in the vicinity of the welding portion with the shaft member in the fixed sheave or the movable sheave. Manufacturing method of pulley for driving force transmission.   5. The press-fitting of the thick portion into the opening is performed in a direction opposite to a direction in which a load is applied from the endless belt to the fixed-side tapered surface or the movable-side tapered surface. Or the manufacturing method of the pulley for driving force transmission of Claim 5.

Images