Pulley device, continuously variable transmission and vehicle

Abstract

To enable further improvement of a structure for a pulley device and thereby enable energy efficiency.SOLUTION: A pulley device provided on an output rotary shaft of a power source, comprises: a fixed sheave; a movable sheave that can move in an axial direction relative to the fixed sheave; and a weight roller that is disposed on a side of the movable sheave opposite to the fixed sheave, and presses the movable sheave toward the fixed sheave by moving radially outward by means of centrifugal force caused by rotation of the output rotary shaft. A contact surface of the movable sheave with the weight roller is formed in a raised shape.SELECTED DRAWING: Figure 8A

Description

[Technical Field]

[0001] The present invention relates to a pulley device that can be applied mainly to a continuously variable transmission. [Background technology]

[0002] In recent years, research and development has been conducted into improving fuel efficiency, which contributes to energy efficiency, in order to ensure that more people have access to affordable, reliable, sustainable and advanced energy. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-193315 Summary of the Invention [Problem to be solved by the invention]

[0004] Regarding the improvement of fuel efficiency, Patent Document 1 describes a structure in which a drive pulley in a continuously variable transmission has multiple rollers built in, and the movable sheave is movable by the centrifugal force generated in each roller. Further improvements are generally required in pulley devices with such a structure.

[0005] The present invention aims to further improve the structure of a pulley device, and ultimately to contribute to energy efficiency. [Means for solving the problem]

[0006] One aspect of the present invention relates to a pulley device, A pulley device provided on an output rotation shaft of a power source, A fixed sheave; a movable sheave that is axially movable relative to the fixed sheave; a weight roller disposed on the opposite side of the movable sheave from the fixed sheave, and moving radially outward by centrifugal force caused by rotation of the output rotary shaft to press the movable sheave toward the fixed sheave, The contact surface of the movable sheave with the weight roller is formed in a raised shape. It is characterized by: [Effects of the Invention]

[0007] According to the present invention, it is possible to further improve the structure of the pulley device, and further to improve energy efficiency. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic side view of a vehicle structure according to an embodiment; [Figure 2] 1 is a cross-sectional view showing an example of the structure of a continuously variable transmission (CVT). [Figure 3] FIG. 2 is an enlarged schematic view of the drive pulley and its surrounding area. [Figure 4] FIG. 4 is a schematic diagram for explaining the detailed structure of a torque cam mechanism. [Figure 5] FIG. 2 is an exploded schematic view of a torque cam mechanism. [Figure 6] 4A and 4B are schematic side views showing the positional relationship of each element in the torque cam mechanism at low and top ratios. [Figure 7A] FIG. 2 is a schematic diagram of a drive pulley as viewed from the movable sheave side. [Figure 7B] FIG. 2 is a schematic diagram of a drive pulley with a ramp plate not shown. [Figure 8A] FIG. 2 is a cross-sectional view showing an example of the structure of a drive pulley. [Figure 8B] FIG. 4 is an enlarged schematic view showing an example of the shape of a contact surface of a movable sheave. [Figure 9] FIG. 10 is a diagram showing evaluation results of gear shift characteristics. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims, and not all combinations of features described in the embodiments are necessarily essential to the invention. Two or more of the features described in the embodiments may be arbitrarily combined. Furthermore, the same reference numerals are used for the same or similar components, and redundant explanations will be omitted.

[0010] <<Vehicle configuration examples>> FIG. 1 is a schematic side view of the structure of a vehicle 1 according to an embodiment. To facilitate understanding of the structure, the figure shows an X-axis, a Y-axis, and a Z-axis that are orthogonal to one another (the same applies to other figures described below). The X-axis corresponds to the front-rear direction, the Y-axis corresponds to the left-right direction, and the Z-axis corresponds to the up-down direction. In this specification, expressions such as front / rear, left / right (side), and up / down indicate relative positional relationships with respect to the vehicle body. For example, expressions such as "front" and "forward" correspond to the +X direction, and expressions such as "rear" and "rearward" correspond to the -X direction.

[0011] The vehicle 1 includes wheels 11, a power unit 12, and a driving operation mechanism 13. In this embodiment, the vehicle 1 is a two-wheeled vehicle that includes front wheels that are steered and rear wheels that are driven as wheels 11, and although the two-wheeled vehicle illustrated here is a scooter type, other examples include a saddle-ride type or a rider type. Furthermore, the number of wheels 11 is not limited to that in this example, and the vehicle 1 may be a four-wheeled vehicle, for example.

[0012] The power unit 12 includes a power source 121 and a power transmission mechanism 122. The power source 121 may be any known configuration capable of generating power, and in this embodiment, an internal combustion engine is used, but in other embodiments, an electric motor may be used. The power (rotation) of the power source 121 is transmitted to the rear wheels, which are drive wheels, via the power transmission mechanism 122. As will be described in detail later, the power transmission mechanism 122 includes a continuously variable transmission (CVT) 2, and power according to the gear ratio is transmitted to the rear wheels (see FIG. 2).

[0013] The driving operation mechanism 13 is mainly provided at a position accessible to the driver (rider) at the front of the vehicle, and is configured, for example, with multiple operators arranged on a handlebar that can change the direction of the front wheels, which are steered. Examples of the operators include an acceleration operator, a braking operator, and a direction indicator operator.

[0014] <<Configuration example of continuously variable transmission>> Fig. 2 is a cross-sectional schematic diagram showing an example of the structure of the CVT 2. In this embodiment, the CVT 2 includes pulley devices 21 and 22 arranged side by side in the X direction, and a belt 23 mounted thereon. Fig. 3 is an enlarged schematic diagram of the pulley device 21 and its surroundings.

[0015] <About the drive pulley> The pulley device 21 is provided on an output rotation shaft AX1 of the power source 121 and receives power from the power source 121. The pulley device 21 will be referred to as a drive pulley 21 in the following description to distinguish it from the pulley device 22. The output rotation shaft AX1 is a rotation shaft (crankshaft in this embodiment) on the power source 121 side in the power transmission mechanism 122, and will be referred to as a drive shaft AX1 in the following description.

[0016] The drive pulley 21 includes a fixed sheave 21a, a movable sheave 21b, a torque cam mechanism 21c, a ramp plate 21d, and a weight roller 21e.

[0017] The sheaves 21a and 21b are generally conical in shape and are arranged opposite each other (the sheaves 21a and 21b may also be referred to as pulley halves). The fixed sheave 21a is fixed to the drive shaft AX1. The movable sheave 21b is supported by the drive shaft AX1 so as to be movable in the axial direction (the direction of the drive shaft AX1; in this embodiment, the Y direction) relative to the fixed sheave 21a. The diameter of the belt 23 wound around and between the sheaves 21a and 21b is kept small while the movable sheave 21b is separated from the fixed sheave 21a, and increases as the movable sheave 21b approaches the fixed sheave 21a.

[0018] The torque cam mechanism 21c is mounted around the drive shaft AX1 between the drive shaft AX1 and the movable sheave 21b, and in this embodiment includes a cam pin 211, a cam pin fixing structure 212, a cam groove forming structure 213, and a cam pin sealing structure 214. The cam pin fixing structure 212 is cylindrically configured to surround the drive shaft AX1 and is fixed to the drive shaft AX1, and the cam pins 211 are engaged with and fixed to the cam pin fixing structure 212. As a result, the cam pins 211 are arranged to extend radially outward from the drive shaft AX1 (in a direction away from the drive shaft AX1). A head 211h of the cam pin 211 extends radially outward from the cam pin fixing structure 212, and this head 211h can be configured to be rotatable. A plurality of cam pins 211 (for example, three) can be arranged. The cam groove forming structure 213 is fixed to the drive shaft AX1 and is cylindrically configured to surround the cam pin fixing structure 212 that fixes the cam pin 211, and has a cam groove T1, and is arranged so as to be movable in the axial direction relative to the cam pin fixing structure 212. The cam pin 211 fixed to the cam pin fixing structure 212 has a head portion 211h that is slidable relative to the cam groove T1 of the cam groove forming structure 213. A plurality of cam grooves T1 (for example, three) can be provided corresponding to the cam pins 211. The cam pin sealing structure 214 is configured in a cylindrical shape so as to surround the cam groove forming structure 213 , and seals the cam pin 211 so that the cam pin 211 does not come off the cam pin fixing structure 212 .

[0019] Here, the cam groove T1 extends in a direction inclined with respect to the axial direction, and as a result, the cam groove forming structure 213 receives a force (thrust force) from the cam pin 211 that moves the movable sheave 21b in the axial direction (Y direction) due to the rotation of the drive shaft AX1. Although details will be described later, in this embodiment, the cam groove forming structure 213 receives a force from the cam pin 211 in a direction (-Y direction) that moves it away from the fixed sheave 21a. With this structure, the cam groove forming structure 213 receives a force in the axial direction from the cam pin 211 due to the rotation of the drive shaft AX1, and the torque cam mechanism 21c generates a force that moves the movable sheave 21b in the axial direction.

[0020] The ramp plate 21d is disposed on the opposite side of the fixed sheave 21a with respect to the movable sheave 21b, and together with the movable sheave 21b, forms a space for accommodating a weight roller 21e, which will be described later.

[0021] The weight roller 21e is disposed on the opposite side of the fixed sheave 21a with respect to the movable sheave 21b, and is housed in a space formed between the movable sheave 21b and the ramp plate 21d so as to be movable radially outward. The contact surface F21b of the movable sheave 21b that contacts the weight roller 21e is inclined with respect to a plane perpendicular to the axial direction (the XZ plane). Therefore, when the drive shaft AX1 rotates, the resulting centrifugal force causes the weight roller 21e to move radially outward, and generates a force in the direction (+Y direction) that moves the movable sheave 21b closer to the fixed sheave 21a. This causes the movable sheave 21b to be pressed toward the fixed sheave 21a. The movement of the weight roller 21e here is a concept that includes rolling and sliding, and the weight roller 21e rolls and / or slides on the contact surface F21b of the movable sheave 21b. Therefore, the contact surface F21b may be expressed as a rolling surface or a sliding surface.

[0022] <About the driven pulley> 2, the pulley device 22 receives power from the drive pulley 21 via a belt 23. The pulley device 22 will be referred to as a driven pulley 22 in the following description to distinguish it from the pulley device 21.

[0023] The driven pulley 22 includes a fixed sheave 22a, a movable sheave 22b, a torque cam mechanism 22c, and a biasing unit 22d.

[0024] Like the sheaves 21a and 21b described above, the sheaves 22a and 22b have a generally conical shape and are arranged opposite each other. The fixed sheave 22a is fixed to the driven shaft AX2. The movable sheave 22b is supported by the driven shaft AX2 so as to be movable in the axial direction (the direction of the driven shaft AX2, the Y direction) relative to the fixed sheave 22a. The diameter of the belt 23 wound around and between the sheaves 22a and 22b is maintained large while the movable sheave 22b is close to the fixed sheave 22a, and becomes smaller as the movable sheave 22b moves away from the fixed sheave 22a.

[0025] The torque cam mechanism 22c has the same function as the torque cam mechanism 21c, that is, it generates a force that moves the movable sheave 22b in the axial direction due to the rotation of the driven shaft AX2.

[0026] The biasing unit 22d biases the movable sheave 22b toward the fixed sheave 22a so that the movable sheave 22b approaches the fixed sheave 22a. Any known biasing means may be used for the biasing unit 22d, and a coil spring is typically used.

[0027] The rotation of the driven shaft AX2 is transmitted directly or indirectly to the rear wheels, which are the driving wheels. In other words, the driven shaft AX2 may be connected to the rotation axis of the rear wheels via another power transmission mechanism, or may substantially coincide with the rotation axis of the rear wheels.

[0028] <Gear ratio> In the configuration of the CVT 2 described above, the belt 23 is installed between the pulleys 21 and 22. For example, when the distance between the sheaves 21a and 21b of the drive pulley 21 becomes smaller (the diameter of the belt 23 wound around them becomes larger), the distance between the sheaves 22a and 22b of the driven pulley 22 becomes larger (the diameter of the belt 23 wound around them becomes smaller). Similarly, when the distance between the sheaves 21a and 21b of the drive pulley 21 becomes larger (the diameter of the belt 23 wound around them becomes smaller), the distance between the sheaves 22a and 22b of the driven pulley 22 becomes smaller (the diameter of the belt 23 wound around them becomes larger). With this configuration, the power of the power source 121 is transmitted to the rear wheel, which is the drive wheel, at a gear ratio according to the diameter of the belt 23 at the drive pulley 21 and the diameter of the belt 23 at the driven pulley 22. Because the diameter of the belt 23 is continuously variable at both the pulleys 21 and 22, the gear ratio is continuously changed and there are no gear stages (i.e., continuously variable transmission).

[0029] For example, when the vehicle 1 is stopped, the movable sheave 21b is spaced apart from the fixed sheave 21a (the diameter of the belt 23 in the drive pulley 21 is small) and the movable sheave 22b is close to the fixed sheave 22a (the diameter of the belt 23 in the driven pulley 22 is large), and the speed ratio of the CVT 2 is large at this time. The state in which the movable sheave 21b is farthest from the fixed sheave 21a and the movable sheave 22b is closest to the fixed sheave 22a is the state in which the speed ratio is largest (low ratio). Thereafter, as the vehicle 1 accelerates, the moving sheave 21b approaches the fixed sheave 21a and the moving sheave 22b moves away from the fixed sheave 22a, continuously decreasing the speed ratio of the CVT 2. The state in which the moving sheave 21b is closest to the fixed sheave 21a and the moving sheave 22b is farthest from the fixed sheave 22a is the state in which the speed ratio is lowest (top ratio).

[0030] The speed change (i.e., the movement of the movable sheaves 21b and 22b) can be determined by the axial forces generated by the torque cam mechanism 21c and weight roller 21e of the drive pulley 21, and the torque cam mechanism 22c and biasing unit 22d of the driven pulley 22. For ease of understanding, the force generated by the torque cam mechanism 21c of the drive pulley 21 is defined as F1 (-Y direction), and the force generated by the weight roller 21e is defined as F2 (+Y direction). Furthermore, the force generated by the torque cam mechanism 22c of the driven pulley 22 is defined as F3 (-Y direction), and the force generated by the biasing unit 22d is defined as F4 (-Y direction). In this case: If |F1+F2|=|F3+F4|, the gear ratio is maintained; If |F1+F2|>|F3+F4|, the top ratio is approached (continuous upshifts); If |F1+F2|<|F3+F4|, the gear ratio approaches a low ratio (shifts down continuously).

[0031] Furthermore, in the configuration of the CVT 2, the direction in which the force F1 of the torque cam mechanism 21c is generated is the -Y direction (the direction in which the movable sheave 21b moves away from the fixed sheave 21a). This allows for a gradual upshift when a high load is applied to the power source 121, for example, when climbing a slope, and thereby enables the vehicle 1 to travel while suppressing a decrease in power performance.

[0032] <<Example of torque cam mechanism configuration>> Fig. 4 is a schematic diagram for explaining the detailed structure of the torque cam mechanism 21c, and Fig. 5 is an exploded schematic diagram thereof. The cam groove forming structure 213 includes a cylindrical portion 2131 in which the cam groove T1 is formed, and a flange portion 2132 provided around one end of the cylindrical portion 2131. The flange portion 2132 is also provided with an attachment portion 2132a for attaching the cam groove forming structure 213 to the main body of the drive pulley 21. The attachment portion 2132a can be fastened with, for example, a bolt or the like.

[0033] The cam groove forming structure 213 is attached to the cam pin fixing structure 212 so as to be movable in the axial direction, and the cam pin fixing structure 212 passes through the cylindrical portion 2131. The cam pin 211 is attached by fitting to the cam pin fixing structure 212 to which the cam groove forming structure 213 is attached, and at this time, the cam pin 211 is slidably inserted through the cam groove T1. Thereafter, the cam pin sealing structure 214 is attached so as to cover the cam pin 211 and the cam groove forming structure 213. In this manner, the torque cam mechanism 21c is assembled.

[0034] As described above, cam groove T1 is formed so that cam groove forming structure 213 receives a force in the -Y direction (i.e., a force in the direction approaching a low ratio) from cam pin 211 due to rotation of drive shaft AX1. The portion of cam groove T1 that generates this effect is shown as first groove portion T11 in the drawing.

[0035] In this embodiment, a second groove portion T12 is further provided as another part of the cam groove T1. The groove portion T12 is connected to the groove portion T11 at one end ET11a of the groove portion T11 (see the enlarged view in FIG. 4). The end ET11a corresponds to the end of the groove portion T11 where the cam pin 211 should be located when the drive shaft AX1 is not rotating (i.e., at a low ratio). The groove portion T12 is formed so that the cam groove forming structure 213 receives a force from the cam pin 211 in the +Y direction (i.e., the direction that brings the movable sheave 21b closer to the fixed sheave 21a, or the direction that brings it closer to the top ratio). The other end opposite the end ET11a is referred to as end ET11b.

[0036] In this way, the grooves T11 and T12 are inclined with respect to the Y direction and extend in different directions so as to exert different functions. With this structure, when the drive shaft AX1 rotates, the groove T11 acts to move the gear ratio closer to a low ratio, and the groove T12 acts to move the gear ratio closer to a top ratio. As shown in the figure, the area between the grooves T11 and T12 is designated as a bent portion T13.

[0037] Figure 6 is a schematic side view showing the positional relationship of each element in the torque cam mechanism 21c at low and top ratios, and also shows a circumferential development of the cylindrical portion 2131 in which the cam groove T1 is formed to make the structure easier to understand.

[0038] The inclination of the groove portion T12 is suppressed compared to that of the groove portion T11. In other words, when the angle formed by the groove portion T11 with the Y direction is θ1 and the angle formed by the groove portion T12 with the Y direction is θ2, θ2<θ1, In this embodiment, as an example, the angle θ1 is set to 45 degrees and the angle θ2 is set to 5 degrees, but in other embodiments, the angle θ1 can be adjusted within a range of 30 to 60 degrees, and the angle θ2 can be adjusted within a range of 0 to 15 degrees.

[0039] Furthermore, the length of the groove T12 in the Y direction is shorter than that of the groove T11. That is, when the length of the groove T11 in the Y direction is L11 and the length of the groove T12 in the Y direction is L12, L12 <L11、 These values ​​can be determined or adjusted depending on the required gear shifting characteristics as well as the sizes of the cam pin 211 and the cam groove forming structure 213. Groove portion T12 is provided to be relatively short, and in this embodiment, when the drive shaft AX1 is not rotating, the cam pin 211 is located in groove portion T12 and extends partially beyond bent portion T13 to the groove portion T11 side. Therefore, the width of groove portion T12 is approximately equal to the diameter of head portion 211h of cam pin 211, but the length of groove portion T12 is shorter than the diameter of head portion 211h of cam pin 211.

[0040] With this structure, when the vehicle 1 is started from a stopped state, the cam pin 211 moves relatively easily from the groove T12 to the groove T11 and then slides in the groove T11. If a high load is applied to the power source 121 while the cam pin 211 slides in the groove T11, the groove T11 acts to bring the power source 121 closer to the low ratio, so that a gradual upshift to the top ratio is achieved.

[0041] On the other hand, for example, when downshifting from a top ratio to a low ratio or while the vehicle is substantially stationary, cam pin 211 is located near groove T12 or end ET11a, and end T12 acts to move the CVT 21 closer to the top ratio. As a result, cam pin 211 presses movable sheave 21b against fixed sheave 21a, which in turn presses movable sheave 21b against belt 23 located between them. This provides a damping effect due to belt 23, and impact noise that may have been generated by cam pin 211 at end ET11a is suppressed compared to a conventional structure without groove T12. Therefore, this embodiment makes it possible to achieve the shifting characteristics of CVT 2 in a manner suited to the load, and also to suppress impact noise of cam pin 211 when in a low ratio.

[0042] In summary, groove T11 is formed so that cam groove forming structure 213 receives force from cam pin 211 in a direction that moves movable sheave 21b away from fixed sheave 21a (direction that moves closer to a low ratio) due to rotation of drive shaft AX1. Groove T12 is connected to groove T11 at end ET11a of groove T11, and is formed so that cam groove forming structure 213 receives force from cam pin 211 in a direction that moves movable sheave 21b closer to fixed sheave 21a (direction that moves closer to a top ratio). This structure makes it possible to achieve the shifting characteristics of CVT 2 to which drive pulley 21 is applied in a manner that corresponds to the load, and also makes it possible to suppress hitting noise of cam pin 211 when the ratio is low.

[0043] In this embodiment, the number of cam pins 211, cam grooves T1, and mounting portions 2132a is three, but the numbers are not limited to this example. Also, in torque cam mechanism 22c, a cam groove having a different shape from cam groove T1 in torque cam mechanism 21c is formed, but a description thereof will be omitted here.

[0044] <<Shape of the contact surface between the movable sheave and the weight roller>> Fig. 7A is a perspective view of the drive pulley 21 as seen from the movable sheave 21b side, and Fig. 7B is a perspective view of the drive pulley 21 without the ramp plate 21d shown in Fig. 7. This shows the state after the weight roller 21e has moved radially outward.

[0045] In this embodiment, a plurality of weight rollers 21e (six in this example) are arranged around the drive shaft AX1 in the space between the movable sheave 21b and the ramp plate 21d. As the drive shaft AX1 rotates, each weight roller 21e moves radially outward due to centrifugal force and applies a force to the contact surface F21b of the movable sheave 21b, thereby pressing the movable sheave 21b toward the fixed sheave 21a.

[0046] FIG. 8A is a schematic diagram showing the cross-sectional structure of the drive pulley 21 taken along the cutting line d1-d1 passing through the two weight rollers 21e, and FIG. 8B is an enlarged schematic diagram of region K1 in FIG. 8A, with the weight rollers 21e not shown. As can be seen from FIG. 8B, the contact surface F21b of the movable sheave 21b is formed with a raised shape. More specifically, in this embodiment, the contact surface F21b is formed with a convex raised shape with a curvature radius of 60 mm on the low ratio side, and is formed with a concave curve with a curvature radius of 34 mm on the top ratio side (see FIG. 9). In the figure, the convex raised portion is indicated as raised portion P1, and the concave curved portion is indicated as curved portion P2. With this structure, the raised portion P1 of the contact surface F21b allows the weight rollers 21e to move radially outward quickly, thereby quickly increasing the centrifugal force generated in the weight rollers 21e.

[0047] 9 is a diagram showing an example of the gear change characteristics at full throttle in comparison with the first and second comparative examples. The horizontal axis represents the vehicle speed V [km / h], and the vertical axis represents the rotation speed Ne [rpm] of the power source 121. In the first comparative example, the contact surface F21b is formed on the low ratio side so as to be inclined in a substantially straight line at an angle of 42 degrees with respect to the X direction (straight line portion P1'), and on the top ratio side so as to be curved concavely with a curvature radius of 28 mm (curved portion P2'). In the second comparative example, this contact surface F21b is formed to be concavely curved with a curvature radius of 250 mm on the low ratio side (curved portion P1"), and is formed to be concavely curved with a curvature radius of 23 mm on the top ratio side (curved portion P2").

[0048] To sum up, First comparison example: Straight line → R(+28) Second comparison example: R(+250) → R(+23) This embodiment: R(-60) → R(+34) It is shown as follows. Regarding the value in parentheses for the radius of curvature R, a positive value indicates a concave curve, and a negative value indicates a convex protrusion. Also, all three examples are designed so that the angle of inclination on the top ratio side is larger than the angle of inclination on the low ratio side, and in the three examples, the radius of curvature R at each portion P1, etc. is set to satisfy this.

[0049] According to the gear change characteristics in Fig. 9, the clutch is in a low ratio state when the vehicle speed V is in the range of 0 to 15 km / h, the clutch is fully engaged when the vehicle speed V is in the range of 15 to 20 km / h, and the clutch is in a top ratio state when the vehicle speed V is in the range of 60 km / h or higher. Although a detailed description will be omitted here, the clutch is built into the driven pulley 22 and is engaged by centrifugal force caused by the rotation of the driven shaft AX2.

[0050] Now, within the vehicle speed V range of 20 to 65 km / h, differences occur in the rotation speed Ne among the above three examples due to the behavior of the movable sheave 21b (more specifically, the behavior of the cam pin 211 in the torque cam mechanism 21c and the behavior of the weight roller 21e). That is, in the first and second comparative examples, even at full throttle, the rotation speed Ne increases and decreases within the vehicle speed V range of 20 to 65 km / h. Such gear change characteristics can cause discomfort to the driver.

[0051] On the other hand, in this embodiment, the raised portion P1 of the contact surface F21b allows the weight roller 21e to move radially outward quickly, thereby quickly increasing the centrifugal force generated in the weight roller 21e. Therefore, the force generated by the weight roller 21e in the +Y direction quickly increases, suppressing an increase in the rotation speed Ne that could occur when the vehicle speed V is in the range of 20 to 40 km / h. After that, the weight roller 21e passes through the raised portion P1 and then the curved portion P2. At this time, the force generated by the weight roller 21e is gradually suppressed, thereby suppressing a decrease in the rotation speed Ne that could occur when the vehicle speed V is in the range of 40 to 65 km / h. In this way, the increase or decrease in the rotation speed Ne can be suppressed.

[0052] In this embodiment, the curved portion P2 is provided outside the raised portion P1, but in another embodiment, a linear inclined surface may be provided as the linear portion instead of the curved portion P2. This structure also allows the force generated by the weight roller 21e to be gently suppressed.

[0053] As described above, due to the rotation of the drive shaft AX1, the cam groove forming structure 213 receives a force in the -Y direction (the aforementioned force F1) from the cam pin 211 via the groove T11. In contrast, when the weight roller 21e passes through the raised portion P1, the force in the +Y direction (the aforementioned force F2) increases, thereby making it easier to approach the top ratio. Therefore, for example, based on a comparison and consideration of these forces, the abutment surface F21b may be formed so that the weight roller 21e passes through the raised portion P1 (more preferably, its center or top) after the cam pin 211 slides from the groove T12 to the groove T11. Additionally, the abutment surface F21b may be formed so that the weight roller 21e passes through the raised portion P1 (more preferably, its center or top) at the timing when the cam pin 211 reaches the end ET11b of the groove T11.

[0054] As described above, according to this embodiment, as can be seen from the comparison with the first and second comparative examples (see FIG. 9), fluctuations in the rotation speed Ne are suppressed when the vehicle speed V is in the range of 20 to 65 km / h, making it possible to achieve gear change characteristics that do not cause discomfort to the driver. The curvature and length of each of the raised portion P1 and the curved portion P2 can be determined or adjusted based on the required speed change characteristics, the size and movement distance of the weight roller 21e, the configuration of the torque cam mechanism 21c, and the configuration of the driven pulley 22. Therefore, the shape of the contact surface F21b is not limited to the example of this embodiment, and the curvature and length of the raised portion P1 and / or the curved portion P2 may be changed as needed, and for the same purpose, the number and arrangement order of them may be changed as needed.

[0055] In the above description, for ease of understanding, each element is denoted by a name related to its function. However, each element is not limited to having the content described in the embodiment as its main function, and may have that function auxiliary to the content. Therefore, each element is not strictly limited to the expression, and the expression can be replaced with a similar expression. In the same spirit, the expression "apparatus" may be replaced with "unit," "component," "piece," "member," "structure," "assembly," etc., or may be omitted or added.

[0056] Furthermore, two or more selectable elements exemplified in the embodiments are not strictly limited to the examples and may be arbitrarily combined, for example, each of the two or more selectable elements may be additionally or alternatively selected. For example, when two elements A and B are arbitrarily combined, they may be expressed as "A and / or B" or "at least one of A and B" to indicate either A only, B only, or both A and B.

[0057] Summary of the embodiment [1] A pulley device (21) provided on an output rotary shaft (AX1) of a power source (121), a fixed sheave (21a); a movable sheave (21b) that is movable axially relative to the fixed sheave; a weight roller (21e) disposed on the opposite side of the movable sheave from the fixed sheave, and moving radially outward by centrifugal force caused by rotation of the output rotary shaft to press the movable sheave toward the fixed sheave, The contact surface (F21b) of the movable sheave with the weight roller is formed in a raised shape. A pulley device characterized by: According to these features, the weight roller can be quickly moved radially outward, and its centrifugal force can be quickly increased, resulting in stabilization of the speed change characteristics, thereby making it possible to provide an even more improved pulley device.

[0058] [2] The contact surface has a concave curved shape or a linear shape outside the raised shape. The pulley device according to [1] above. In the embodiment, when the raised portion is defined as a raised portion, a curved portion, which is a curved portion, is formed radially outward from the raised portion, so that the force generated by the weight roller is quickly increased by the raised portion and then gradually suppressed by the curved portion.

[0059] [3] a mechanism (21c) that is provided around the output rotary shaft between the output rotary shaft and the movable sheave and that is capable of generating a force that moves the movable sheave in the axial direction; The pulley device according to [1] or [2] above. According to such a feature, it is possible to realize the speed change characteristics of a continuously variable transmission to which the pulley device is applied in a manner according to the load, thereby making it possible to provide a further improved pulley device.

[0060] [4] The mechanism comprises: a cam pin (211) extending radially outward from the output rotary shaft; a cam groove forming structure (213) having a cam groove (T1) in which the cam pin can slide; a torque cam mechanism (21c) including The cam groove is a first groove portion (T11) formed so that the cam groove forming structure receives a force from the cam pin in a first direction that separates the movable sheave from the fixed sheave due to rotation of the output rotation shaft; a second groove portion (T12) that is connected to the first groove portion at one end of the first groove portion where the cam pin is located when the output rotation shaft is not rotating, and that is formed so that the cam groove forming structure receives a force from the cam pin in a second direction opposite to the first direction; Including, The contact surface is formed so that, when the rotation of the output rotary shaft starts, the cam pin slides from the second groove portion to the first groove portion, and then the weight roller passes through the raised shape on the contact surface. The pulley device according to [3] above. According to this feature, it is possible to suppress the hitting noise of the cam pin at a low ratio, thereby providing a further improved pulley device, and in this case, the effect of [1] above can be more suitably obtained.

[0061] [5] A drive pulley (21) that is the pulley device according to any one of the above [1] to [4]; A driven pulley (22), and a belt (23) stretched between the drive pulley and the driven pulley. A continuously variable transmission (2). That is, the pulley device can be widely applied to desired continuously variable transmissions.

[0062] [6] The continuously variable transmission (2) described in [5] above; Wheels (11) and A vehicle (1) characterized by: That is, the continuously variable transmission can be widely applied to desired vehicles.

[0063] The invention is not limited to the above-described embodiment, and various modifications and variations are possible within the scope of the gist of the invention. [Explanation of symbols]

[0064] 21: drive pulley (pulley device), 21a: fixed sheave, 21b: movable sheave, 21e: weight roller, F21b: contact surface.

Claims

1. A pulley device provided on an output rotation shaft of a power source, A fixed sheave; a movable sheave that is axially movable relative to the fixed sheave; a weight roller disposed on the opposite side of the movable sheave from the fixed sheave, and moving radially outward by centrifugal force caused by rotation of the output rotary shaft to press the movable sheave toward the fixed sheave, The contact surface of the movable sheave with the weight roller is formed in a raised shape. A pulley device characterized by:

2. The contact surface has a concave curved shape or a linear shape outside the raised shape.

2. The pulley device according to claim 1.

3. a mechanism that is provided around the output rotary shaft between the output rotary shaft and the movable sheave and that is capable of generating a force that moves the movable sheave in the axial direction; 2. The pulley device according to claim 1.

4. The mechanism comprises: a cam pin extending radially outward from the output rotary shaft; a cam groove forming structure having a cam groove in which the cam pin can slide; A torque cam mechanism comprising: The cam groove is a first groove portion formed so that the cam groove forming structure receives a force from the cam pin in a first direction that separates the movable sheave from the fixed sheave due to rotation of the output rotation shaft; a second groove portion that is connected to the first groove portion at one end of the first groove portion where the cam pin is located when the output rotation shaft is not rotating, and that is formed so that the cam groove forming structure receives a force from the cam pin in a second direction opposite to the first direction; Including, The contact surface is formed so that, when the rotation of the output rotary shaft starts, the cam pin slides from the second groove portion to the first groove portion, and then the weight roller passes through the raised shape on the contact surface.

4. The pulley device according to claim 3.

5. A drive pulley that is the pulley device according to any one of claims 1 to 4; A driven pulley; a belt stretched between the drive pulley and the driven pulley. A continuously variable transmission characterized by:

6. The continuously variable transmission according to claim 5; Wheels and A vehicle characterized by:

Images