Pulley device, continuously variable transmission and vehicle

Abstract

To provide a technology advantageous in terms of maintainability of a pulley device.SOLUTION: A pulley device provided on an output rotary shaft of a power source comprises: a fixed sheave fixed to the output rotary shaft; a movable sheave that can move in an axial direction of the output rotary shaft relative to the fixed sheave; and a torque cam mechanism that is disposed around the output rotary shaft between the output rotary shaft and the movable sheave, and can generate force that moves the movable sheave in the axial direction. The torque cam mechanism includes a cam pin projecting radially outward from the output rotary shaft, and a cam groove forming structure having a cam groove in which the cam pin is slidable. The cam groove forming structure is attached to the movable sheave by bolt fastening.SELECTED DRAWING: Figure 7

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] Patent Document 1 describes a structure in which a drive pulley in a continuously variable transmission has multiple rollers built in, and a movable sheave is movable by the centrifugal force generated in each roller. The drive pulley (pulley device) of a continuously variable transmission is provided with parts that need to be replaced periodically, and improving maintainability, such as making the replacement of such parts easier, can lead to improved fuel efficiency.

[0005] Therefore, an object of the present invention is to provide a technique that is advantageous in terms of the maintainability of a pulley device, which in turn contributes to improving energy efficiency. [Means for solving the problem]

[0006] In order to achieve the above object, one aspect of the present invention is a pulley device provided on an output rotation shaft of a power source, the pulley device including: a fixed sheave fixed to the output rotation shaft; a movable sheave movable in an axial direction of the output rotation shaft relative to the fixed sheave; a ramp plate disposed on the opposite side of the fixed sheave with respect to the movable sheave; and a weight roller accommodated in a space formed by the movable sheave and the ramp plate;a torque cam mechanism that is circumferentially provided on the output rotation shaft between the output rotation shaft and the movable sheave and that is capable of generating a force that moves the movable sheave in the axial direction, the torque cam mechanism having a cam pin that protrudes radially outward from the output rotation shaft and a cam groove forming structure that has a cam groove in which the cam pin can slide, the movable sheave has an opening through which the output rotation shaft passes and a fastening surface provided on the space side, The cam groove forming structure is When the movable sheave is inserted into the opening, The movable sheave is fastened by bolts. The fastened surface of The device is characterized in that it is attached to [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a technique that is advantageous in terms of the maintainability of a pulley device, and furthermore, it is possible 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 7] FIG. 2 is a schematic diagram showing a state in which a movable sheave and a cam groove forming structure are disassembled. [Figure 8] 10 is a schematic diagram of the movable sheave with the cam groove forming structure attached, viewed from the -Y direction side. FIG. 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 surrounding area.

[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 (roller portion) 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] Ramp plate 21d is disposed on the opposite side of fixed sheave 21a with respect to movable sheave 21b, and together with movable sheave 21b, forms a space for accommodating weight roller 21e, which will be described later. Groove portions 216, into which slide portions 215 of movable sheave 21b slidably fit, are partially (for example, in three locations) provided on the outer edge of ramp plate 21d. Slide pieces 21f (which may also be referred to as guide pieces) made of synthetic resin with excellent sliding properties are attached to groove portions 216 of ramp plate 21d, and the slide portions 215 of movable sheave 21b slidably engage with the slide pieces 21f. The slide portions 215 of movable sheave 21b are portions that protrude in the axial direction (-Y direction) from part of the outer periphery of movable sheave 21b, and may be configured, for example, in the shape of a plate having a thickness in the circumferential direction. The groove 216 of the ramp plate 21d and the slide portion 215 of the movable sheave 21b may be understood as a mechanism for guiding the relative movement in the axial direction between the movable sheave 21b and the ramp plate 21d. Here, a wall portion 219 having an outer surface that is the outermost end in the radial direction of the movable sheave 21b is provided on the outer periphery of the movable sheave 21b and extends in the axial direction (-Y direction). In this embodiment, the slide portion 215 is connected to a part of the wall portion 219 and is configured to protrude further in the axial direction (-Y direction) than the wall portion 219.

[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 within the movable sheave 21b, and generates a force in a 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. The contact surface F21b may also be understood as a guide surface that guides the movement of the weight roller 21e within the movable sheave 21b.

[0022] <About the driven pulley> Next, the pulley device 22 will be described with reference to Fig. 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, 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] <About 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 of the drive pulley 21 is spaced apart from the fixed sheave 21a (the diameter of the belt 23 of the drive pulley 21 is small), and the movable sheave 22b of the driven pulley 22 is close to the fixed sheave 22a (the diameter of the belt 23 of the driven pulley 22 is large), so the speed ratio of the CVT 2 is large. In other words, the state in which the movable sheave 21b of the drive pulley 21 is farthest from the fixed sheave 21a and the movable sheave 22b of the driven pulley 22 is closest to the fixed sheave 22a is the state in which the speed ratio is largest (low ratio (equivalent to low gear)). Thereafter, as the vehicle 1 accelerates, the movable sheave 21b of the drive pulley 21 approaches the fixed sheave 21a, and the movable sheave 22b of the driven pulley 22 moves away from the fixed sheave 22a, thereby continuously decreasing the speed ratio of the CVT 2. In other words, the state in which the movable sheave 21b of the drive pulley 21 is closest to the fixed sheave 21a, and the movable sheave 22b of the driven pulley 22 is farthest from the fixed sheave 22a, is the state in which the speed ratio is lowest (top ratio (equivalent to top gear)).

[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 CVT2, 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 gradual upshifting when a high load is applied to the power source 121, for example, when climbing a slope, thereby enabling driving while suppressing a decrease in power performance.

[0032] <<Example of torque cam mechanism configuration>> Fig. 4 is a schematic diagram illustrating the detailed structure of the torque cam mechanism 21c, and Fig. 5 is an exploded schematic diagram thereof. The cam groove forming structure 213 is attached to the movable sheave 21b of the drive pulley 21 by bolting. It includes a cylindrical portion 2131 in which the cam groove T1 is formed, a flange portion 2132 provided around one end of the cylindrical portion 2131, and an extension portion 2133 that partially extends radially outward from the flange portion 2132. The extension portion 2133 can function as an attachment portion for attaching the cam groove forming structure 213 to the movable sheave 21b of the drive pulley 21. The attachment of the cam groove forming structure 213 to the movable sheave 21b will be described in detail below.

[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 50 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 2 closer to the top ratio. As a result, cam pin 211 presses the movable sheave toward fixed sheave 21a, causing movable sheave 21b to be pressed against belt 23 interposed between movable sheave 21b and fixed sheave 21a. This provides a damping effect due to belt 23, and reduces impact noise that may have been generated by cam pin 211 at end ET11a compared to a conventional structure without groove T12. Therefore, this embodiment enables the CVT 2 to achieve gear shifting characteristics suited to the load and also reduces impact noise generated by cam pin 211 when the CVT 2 is 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 and the number of cam grooves T1 are three, but the numbers are not limited to this example. Also, in the torque cam mechanism 22c of the driven pulley 22, a cam groove having a different shape from the cam groove T1 in the torque cam mechanism 21c of the drive pulley 21 is formed, but a description thereof will be omitted here.

[0044] <<Attaching the cam groove forming structure to the movable sheave>> Fig. 7 is a schematic diagram for explaining the attachment of the cam groove forming structure 213 to the movable sheave 21b, showing the movable sheave 21b and the cam groove forming structure 213 disassembled. Fig. 8 is a schematic diagram of the movable sheave 21b with the cam groove forming structure 213 attached, viewed from the -Y direction, showing a state in which the output drive shaft AX is stationary. Fig. 8 also shows the slide piece 21f and the weight roller 21e. In this embodiment, the cam groove forming structure 213 is attached to the movable sheave 21b by bolting.

[0045] As described above, the cam groove forming structure 213 includes a cylindrical portion 2131 in which the cam groove T1 is formed, a flange portion 2132 provided around one end of the cylindrical portion 2131, and an extending portion 2133 that partially extends radially outward from the flange portion 2132. In the cam groove forming structure 213 of this embodiment, a plurality of (three in FIG. 7) extending portions 2133 are provided at equal intervals in the circumferential direction. Each extending portion 2133 is provided with an opening 2133a through which a bolt 21g is inserted.

[0046] As described above, the movable sheave 21b has an abutment surface F21b against which the weight roller 21e abuts when the weight roller 21e moves radially outward due to centrifugal force caused by rotation of the drive shaft AX1. The abutment surface F21b defines the space in which the weight roller 21e moves. The movable sheave 21b also has a slide portion 215, an opening 217, and a fastened portion 218. As described above, the slide portion 215 is a portion that protrudes in the axial direction (-Y direction) from a portion of the outer periphery of the movable sheave 21b, and is slidably engaged with the groove portion 216 of the ramp plate 21d via the slide piece 21f. The cylindrical portion 2131 of the cam groove forming structure 213 is inserted into the opening 217. The fastened portion 218 is a portion to which the cam groove forming structure 213 is fastened with a bolt. In this embodiment, a plurality of (three in FIG. 7) fastening portions 218 are arranged at positions corresponding to the plurality of extending portions 2133 of the cam groove forming structure 213. Each fastening portion 218 has a fastening surface 218a to which the extending portion 2133 of the cam groove forming structure 213 is fastened with a bolt, and the fastening surface 218a is provided with a screw hole 218b into which the bolt 21g is screwed.

[0047] In the above configuration, when attaching the cam groove forming structure 213 to the movable sheave 21b, the bolt 21g is inserted into the opening 2133a provided in the extension portion 2133 of the cam groove forming structure 213, and the bolt 21g is then screwed into the threaded hole 218b of the fastening surface 218a. On the other hand, when removing the cam groove forming structure 213 from the movable sheave 21b, the bolt 21g screwed into the threaded hole 218b of the fastening surface 218a is loosened. As described above, according to the configuration of this embodiment, the cam groove forming structure 213, in which wear of the cylindrical portion 2131 (cam groove T1) may occur due to sliding of the cam pin 211, can be easily attached to and removed from the movable sheave 21b using only the bolt 21g. In other words, the maintainability of the drive pulley 21 can be improved.

[0048] Furthermore, the fastened portion 218 of the movable sheave 21b is provided with a protrusion 218c into which the extending portion 2133 of the cam groove forming structure 213 is fitted. The protrusion 218c protrudes from the fastened surface 218a so as to abut against the outer surface of the extending portion 2133 when the cam groove forming structure 213 is attached to the movable sheave 21b, and the outer surface of the extending portion 2133 and the inner surface of the protrusion 218c form a spigot structure. By providing such a protrusion 218 on the fastened portion 218, the cam groove forming structure 213 can be attached to the movable sheave 21b with high precision so that the rotation axis (rotation center) of the cam groove forming structure 213 and the rotation axis (rotation center) of the movable sheave 21b are coaxial. As a result, it is possible to obtain effects such as reducing unevenness in the load on the multiple cam pins 211 that fit into the multiple cam grooves T1 of the cam groove forming structure 213 and reducing wobble of the belt 23. That is, the durability of the drive pulley 21 can be improved.

[0049] 7 and 8, in the drive pulley 21 of this embodiment, the fastened portion 218 and the sliding portion 215 of the movable sheave 21b are arranged along the radial direction. That is, the fastened portion 218 and the sliding portion 215 are arranged so as to at least partially overlap in the circumferential direction. This arrangement ensures a sufficient movement space for the weight roller 21e and reduces the expansion of the movable sheave 21b in the circumferential and radial directions caused by fastening the cam groove forming structure 213 with bolts. In other words, it is possible to achieve both improved maintainability and a more compact drive pulley 21 (movable sheave 21b).

[0050] 8, the drive pulley 21 of this embodiment is configured so that the radial distance La between the outer surface of the extension portion 2133 of the cam groove forming structure 213 and the drive shaft AX1 is longer than the radial distance Lb between the weight roller 21e and the drive shaft AX1 when the drive shaft AX1 is not rotating. This configuration is achieved by providing the fastened portion 218 of the movable sheave 21b between two circumferentially adjacent weight rollers 21e. This configuration, like the configuration in which the fastened portion 218 and the slide portion 215 are arranged radially, ensures a sufficient movement space for the weight rollers 21e and reduces the circumferential and radial expansion of the movable sheave 21b caused by bolting the cam groove forming structure 213. In other words, it is possible to achieve both improved maintainability and a more compact drive pulley 21 (movable sheave 21b).

[0051] In this embodiment, the number of each of the fastened portions 218 of the movable sheave 21b and the extension portions 2133 of the cam groove forming structure 213 is three, but the number of each is not limited to this example. Also, the number of weight rollers 21e arranged between two fastened portions 218 adjacent to each other in the circumferential direction is two, but the number of each weight roller 21e is not limited to this example and may be one or three or more.

[0052] As described above, in the drive pulley 21 of this embodiment, the cam groove forming structure 213 is attached to the movable sheave 21b by bolting. With this configuration, the cam groove forming structure 213, which requires periodic replacement due to wear, can be easily attached to and detached from the movable sheave 21b using only the bolts 21g. In other words, the maintainability of the drive pulley 21 can be improved.

[0053] 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.

[0054] 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.

[0055] Summary of the embodiment (Item 1) A pulley device (e.g., 21) provided on an output rotation shaft (e.g., AX1) of a power source (e.g., 121), a fixed sheave (e.g., 21a) fixed to the output rotary shaft; a movable sheave (e.g., 21b) that is movable in the axial direction of the output rotation shaft relative to the fixed sheave; a torque cam mechanism (e.g., 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; Equipped with The torque cam mechanism has a cam pin (e.g., 211) protruding radially outward from the output rotation shaft, and a cam groove forming structure (e.g., 213) having a cam groove (e.g., T1) in which the cam pin can slide, The pulley device is characterized in that the cam groove forming structure is attached to the movable sheave by fastening bolts. According to this item, the cam groove forming structure, which requires periodic replacement due to wear, can be easily attached to and detached from the movable sheave using only bolts, thereby improving the maintainability of the pulley device.

[0056] (Item 2) Further provided is a ramp plate (e.g., 21d) disposed on the opposite side of the fixed sheave with respect to the movable sheave, The movable sheave has a fastening portion (e.g., 218) to which the cam groove forming structure is bolted, and a slide portion (e.g., 215) slidably engaged with the groove portion of the ramp plate, 2. The pulley device according to item 1, wherein the fastened portion and the sliding portion are arranged along the radial direction. According to this item, the size of the movement space of the weight roller can be secured and the circumferential and radial expansion of the movable sheave caused by bolting the cam groove forming structure can be reduced, thereby making it possible to achieve both improved maintainability and a smaller pulley device (movable sheave).

[0057] (Item 3) The cam groove forming structure has a cylindrical portion (e.g., 2131) in which the cam groove is provided, a flange portion (e.g., 2132) provided around one end of the cylindrical portion, and an extension portion (e.g., 2133) partially extending outward in the radial direction from the flange portion, 3. The pulley device according to item 2, wherein the extension portion is fastened to the fastened portion of the movable sheave by a bolt. According to this item, the extension provided on the flange portion of the cam groove forming structure can be fastened to the movable sheave with a bolt, thereby improving the maintainability of the pulley device.

[0058] (Item 4) 4. The pulley device according to item 3, wherein the fastened portion has a protrusion (for example, 218c) into which the extension portion of the cam groove forming structure is spigot-fitted. According to this item, the cam groove forming structure can be attached to the movable sheave with high precision, which results in the effects of reducing unevenness in the load on the multiple cam pins that fit into the multiple cam grooves of the cam groove forming structure and reducing wobble of the belt suspended on the pulley device, thereby improving the durability of the pulley device.

[0059] (Item 5) The rotor further includes a weight roller (e.g., 21e) that moves radially outward by centrifugal force caused by rotation of the output rotary shaft and presses the movable sheave toward the fixed sheave, 5. The pulley device according to item 3 or 4, wherein the radial distance (e.g., La) between the outer surface of the extension portion of the cam groove forming structure and the output rotation shaft is longer than the radial distance (e.g., Lb) between the weight roller and the output rotation shaft when the output rotation shaft is not rotating. According to this item, the size of the movement space of the weight roller can be secured and the circumferential and radial expansion of the movable sheave caused by bolting the cam groove forming structure can be reduced, thereby making it possible to achieve both improved maintainability and a smaller pulley device (movable sheave).

[0060] (Item 6) A drive pulley (e.g., 21) that is the pulley device according to any one of items 1 to 5; a driven pulley (e.g., 22); a belt (e.g., 23) stretched between the driving pulley and the driven pulley; A continuously variable transmission (e.g., 2) characterized by comprising: According to this item, it is possible to provide a continuously variable transmission equipped with a pulley device with improved maintainability.

[0061] (Item 7) A vehicle (for example, 1) comprising the continuously variable transmission according to item 6 and a wheel (for example, 11). According to this item, it is possible to provide a vehicle to which a continuously variable transmission equipped with a pulley device with improved maintainability is applied.

[0062] 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]

[0063] 21: drive pulley (pulley device), 21a: fixed sheave, 21b: movable sheave, 21c: torque cam mechanism, 21e: weight roller, 211: cam pin, 213: cam groove forming structure, 215: slide portion, 218: fastened portion, 2131: cylindrical portion, 2132: flange portion, 2133: extension portion (mounting portion)

Claims

1. A pulley device provided on an output rotation shaft of a power source, a fixed sheave fixed to the output rotary shaft; a movable sheave that is movable in the axial direction of the output rotary shaft relative to the fixed sheave; a ramp plate disposed on the opposite side of the fixed sheave with respect to the movable sheave; a weight roller accommodated in a space formed by the movable sheave and the ramp plate; a torque cam mechanism that is circumferentially provided on 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; Equipped with the torque cam mechanism includes a cam pin protruding radially outward from the output rotation shaft and a cam groove forming structure having a cam groove in which the cam pin can slide, the movable sheave has an opening through which the output rotation shaft passes and a fastening surface provided on the space side, The pulley device is characterized in that the cam groove forming structure is attached to the fastening surface of the movable sheave by bolting in the space while being inserted into the opening of the movable sheave.

2. The movable sheave has a slide portion slidably engaged with a groove portion of the ramp plate on the space side, The pulley device according to claim 1 , wherein the fastened surface and the slide portion are arranged along the radial direction.

3. the cam groove forming structure has a cylindrical portion in which the cam groove is provided, a flange portion provided around one end of the cylindrical portion, and an extension portion partially extending outward in the radial direction from the flange portion, 2. The pulley device according to claim 1, wherein, in a state where the cylindrical portion is inserted into the opening of the movable sheave, the extension portion contacts the fastened surface of the movable sheave and is fastened with a bolt.

4. 4. The pulley device according to claim 3, wherein the fastened surface has a protrusion with which the extension of the cam groove forming structure is fitted in a spigot-fit manner.

5. The weight roller moves radially outward due to centrifugal force caused by rotation of the output rotary shaft, and presses the movable sheave toward the fixed sheave, 4. The pulley device according to claim 3, wherein the radial distance between the outer surface of the extension portion of the cam groove forming structure and the output rotation shaft is longer than the radial distance between the weight roller and the output rotation shaft when the output rotation shaft is not rotating.

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

7. A vehicle comprising the continuously variable transmission according to claim 6 and a wheel.

Images