JP2016038001A - Belt type stepless speed change device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a belt type stepless speed change device capable of improving lubricity of a contact surface between each of the sheaves and a belt.SOLUTION: This invention relates to a belt type stepless speed change device comprising a pair of pulleys 3(5) having each of a fixed sheave 7 integrally formed with a rotating shaft 2 and a movable sheave 8 fitted to the rotating shaft 2 enabling an integral rotation with the rotating shaft 2 to be carried out and enabling motion in an axial direction of the rotating shaft 2; and a belt 6 wound around the pair of pulleys 3(5) to transmit a torque in which a portion of the outer circumferential part of the rotating shaft 2 between each of the sheaves 7, 8 is applied as at least a guide part 41 of which outer diameter is gradually increased toward any one of the sheave 7, and there is provided a nozzle part for injecting oil lubricating a contact part between each of the sheaves 7, 8 and the belt 6 toward at least any one location of the guide part 41.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a belt-type continuously variable transmission that includes a pair of pulleys and a belt wound around the pulleys, and that changes a gear ratio by changing a winding radius of the belt.

  Patent Document 1 describes a belt-type continuously variable transmission in which a belt is wound around a pair of pulleys. This belt-type continuously variable transmission forms a hollow portion formed in the rotating shaft and an oil passage communicating with the outer peripheral surface of the rotating shaft, and oil discharged from the oil passage forms a contact surface between each sheave and the belt. It is configured to lubricate. In order to prevent the movable sheave from closing the opening of the oil passage when the movable sheave comes closest to the fixed sheave, the rotating shaft has an outer diameter as it approaches the fixed sheave side. Is formed so that an oil passage is opened in the tapered portion.

JP 2003-194191 A

  In the belt-type continuously variable transmission described in Patent Document 1, when the movable sheave is closest to the fixed sheave, the movable sheave is located outside the portion where the oil passage is opened. Cannot immediately flow toward the outer peripheral side of the movable sheave. Therefore, oil is stored between the inner peripheral surface of the movable sheave that slides while being fitted to the rotary shaft and the outer peripheral surface of the rotary shaft. If centrifugal force acts on the oil attached to the outer peripheral surface of the tapered portion of the stored oil, the oil may flow toward the opening of the oil passage along the outer peripheral surface of the tapered portion. is there. In this way, the oil flowing toward the opening of the oil passage exerts a pressure in a direction that hinders the flow of the oil for lubrication, so that lubrication may be insufficient.

  The present invention has been made paying attention to the above technical problem, and aims to provide a belt-type continuously variable transmission capable of improving the lubricity of the contact surface between each sheave and the belt. It is.

  In order to achieve the above object, the invention according to claim 1 is configured so that the fixed sheave integrated with the rotating shaft and the rotating shaft can rotate together with the rotating shaft and move in the axial direction of the rotating shaft. In a belt-type continuously variable transmission comprising a pair of pulleys each having a movable sheave fitted to the rotating shaft and a belt that is wound around the pair of pulleys and transmits torque, an outer peripheral portion of the rotating shaft The portion between each sheave is a guide portion whose outer diameter is gradually increased toward at least one of the sheaves, and between each sheave and the belt toward at least one of the guide portions. The nozzle part which ejects the oil which lubricates a contact part is provided.

  The invention of claim 2 is the invention of claim 1, wherein the maximum outer diameter of the guide portion is formed smaller than the inner diameter of the movable sheave, and the portion of the guide portion that has the maximum outer diameter is The belt-type continuously variable transmission is configured to be located at a position where the movable sheave contacts and fits in an outer peripheral portion of the rotating shaft.

  According to a third aspect of the invention, in the first or second aspect of the invention, the rotating shaft and the fixed sheave are integrally formed, and the rotating shaft has a stress generated when the fixed sheave receives a load from a belt. An annular groove for reducing concentration is formed, and the guide portion is formed in a shape in which an outer diameter gradually increases from the annular groove toward the movable sheave. Machine.

  A fourth aspect of the invention is the belt type continuously variable transmission according to the third aspect of the invention, wherein the nozzle portion is configured to inject the oil toward the annular groove. .

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the fixed sheave has a conical surface that faces the movable sheave side in the axial direction of the rotation shaft, and the guide portion is The belt-type continuously variable transmission is formed in a shape in which an outer diameter gradually increases from a position where the fixed sheave and the rotating shaft are connected to the movable sheave side.

  A sixth aspect of the present invention includes the hydraulic actuator according to any one of the first to fifth aspects, wherein a hydraulic actuator is applied to a back surface of the movable sheave so as to move the movable sheave in an axial direction of the rotation shaft. A belt-type continuously variable, wherein a part of the oil supplied to the hydraulic actuator leaks from a fitting portion between the movable sheave and the rotating shaft and flows to the guide portion. It is a transmission.

  The invention of claim 7 is the invention according to any one of claims 1 to 6, wherein a part of the oil supplied so as to lubricate a fitting portion between the movable sheave and the rotating shaft is the movable sheave and the A belt-type continuously variable transmission configured to leak from a fitting portion with a rotating shaft and flow to the guide portion.

  According to an eighth aspect of the present invention, in the invention according to any one of the first to seventh aspects, the rotary shaft provided in one of the pair of pulleys is transmitted with torque from a power source, and the pair of pulleys The rotation shaft provided on the other pulley transmits torque to the output member, and the rotation shaft provided on the one pulley and the rotation shaft provided on the other pulley have the guide portion. The angle formed by the outer peripheral surface of the guide portion on the rotary shaft provided on the one pulley and the central axis of the rotary shaft is such that the outer peripheral surface of the guide portion on the rotary shaft provided on the other pulley and the rotary shaft The belt type continuously variable transmission is characterized in that it is formed larger than the angle formed by the central axis of the belt type continuously variable transmission.

  The invention of claim 9 is the invention according to any one of claims 1 to 8, wherein the belt is fitted into a plurality of plate-like links and a connection hole formed in the link, and the links are connected in an annular shape. In addition, the belt type continuously variable transmission includes a chain belt provided with both ends in the axial direction and pins serving as power transmission surfaces in contact with the sheaves.

  According to the present invention, the portion between the sheaves on the outer peripheral surface of the rotating shaft of the pulley is a guide portion whose outer diameter gradually increases toward at least one of the sheaves. Further, oil that lubricates a contact portion between each sheave and the belt is ejected toward at least one of the guide portions. Therefore, the oil ejected toward the guide portion flows through the guide portion due to centrifugal force and surface tension. Since the oil that has flowed through the guide portion flows toward the fixed sheave or the movable sheave, the surface where the sheave and the belt come into contact can be lubricated. In addition, since pressure does not act in a direction that hinders the flow of oil flowing through the guide portion, it is possible to suppress a decrease in the amount of oil flowing through the contact portion between the sheave and the belt.

  In addition, by configuring the portion of the guide portion having the largest outer diameter to be located at a position where the movable sheave contacts and fits in the outer peripheral portion of the rotating shaft, the oil flowing through the guide portion is It is possible to suppress scattering to the outer peripheral side due to centrifugal force. Therefore, it is possible to suppress a decrease in the amount of oil flowing on the contact surface between the sheave and the belt.

  Furthermore, the angle formed by the guide portion of the rotating shaft to which torque is transmitted from the power source and the central axis of the rotating shaft is defined by the guide portion of the rotating shaft transmitting torque to the output member and the central axis of the rotating shaft. By forming it larger than the angle, it is possible to flow a large amount of oil in a sheave having a relatively high surface pressure to act on, and to suppress a decrease in rigidity of the rotating shaft that transmits torque to the output member. it can.

It is sectional drawing for demonstrating an example of a structure of the primary pulley in this invention. It is a mimetic diagram for explaining an example of composition of a belt type continuously variable transmission concerning this invention. It is an enlarged view for demonstrating an example of a structure of a chain belt. It is a schematic diagram for demonstrating an example of the structure which sprays oil on an input shaft and an output shaft. It is a schematic diagram for demonstrating an example of a structure of a nozzle. It is a figure which shows the change of the surface pressure which acts on each conical surface according to a gear ratio.

  The belt type continuously variable transmission according to the present invention includes a pair of pulleys each having a fixed sheave and a movable sheave, and a belt wound around the pulleys. An example of the configuration of the belt-type continuously variable transmission configured as described above is shown in FIG. The belt type continuously variable transmission (hereinafter referred to as CVT1) shown in FIG. 2 is configured almost the same as a conventionally known one, and includes an input shaft 2 to which torque is transmitted from a power source such as an engine, and the like. A primary pulley 3 connected to the input shaft 2, an output shaft 4 for transmitting torque to an output member such as a drive wheel, a secondary pulley 5 connected to the output shaft 4, and the pulleys 3 and 5 are wound around And the endless belt 6 formed. The input shaft 2 and the output shaft 4 are arranged in parallel.

  The primary pulley 3 includes a conical first fixed sheave 7 and a first movable sheave 8, and the first fixed sheave 7 is formed integrally with the input shaft 2. Further, the first movable sheave 8 is fitted to the input shaft 2 so as to change the speed ratio by approaching or separating from the first fixed sheave 7. Specifically, the first movable sheave 8 is engaged with the input shaft 2 by a spline or the like so as to rotate integrally with the input shaft 2 and to move in the axial direction. The conical surfaces 9 and 10 of the sheaves 7 and 8 are arranged to face each other in the axial direction of the input shaft 2, and the first V groove 11 is formed by the conical surfaces 9 and 10.

  The first movable sheave 8 is provided with a first hydraulic actuator 12 so as to press the side surface opposite to the conical surface 10 in the axial direction of the input shaft 2 toward the first fixed sheave 7 side. Accordingly, by supplying oil to the first hydraulic actuator 12, the first movable sheave 8 receives a load so as to approach the first fixed sheave 7.

  The secondary pulley 5 shown in FIG. 2 is configured in the same manner as the primary pulley 3, and includes a conical second fixed sheave 13 and a second movable sheave 14, and the second fixed sheave 13 is the output shaft 4. Are integrally formed. The second movable sheave 14 is engaged with the output shaft 4 by a spline or the like so as to approach or separate from the second fixed sheave 13. The conical surfaces 15 and 16 of the sheaves 13 and 14 are disposed so as to face the output shaft in the axial direction, and the second V groove 17 is formed by the conical surfaces 15 and 16.

  The second movable sheave 14 is provided with a second hydraulic actuator 18 so as to press the side surface opposite to the conical surface 16 in the axial direction of the output shaft 4 toward the second fixed sheave 13 side. Therefore, by supplying oil to the second hydraulic actuator 18, the second movable sheave 14 receives a load so as to approach the second fixed sheave 13.

  An endless chain belt 6 is wound around the primary pulley 3 and the secondary pulley 5 configured as described above. More specifically, the chain belt 6 is wound around the V grooves 11 and 17. Here, an example of the configuration of the chain belt 6 will be described with reference to FIG. In addition, the horizontal direction in FIG. 3 has shown the longitudinal direction of the chain belt 6, and the vertical direction has shown the thickness direction of the chain belt 6. FIG. The chain belt 6 shown in FIG. 3 has a plurality of pins 19 that are formed in the same length as the width of the chain belt 6 and are arranged in parallel to each other, and a plurality of links 21 that are annularly connected by the pins 19. It is constituted by. The link 21 shown here is an annular plate member in which a communication hole 20 through which the pin 19 is passed is formed, and pin holding portions 22 having an inner diameter substantially the same as the outer diameter of the pin 19 are formed at both ends thereof. ing. More specifically, the width of the central portion sandwiched between the pin holding portions 22 is formed to be smaller than the outer diameter of the pin 19, and the pin 19 does not move from the pin holding portion 22 in the longitudinal direction of the chain belt 6. It is formed as follows. Then, the plurality of links 21 are stacked in the width direction of the chain belt 6, and the adjacent links 21 are disposed after being shifted in the longitudinal direction of the chain belt 6 by the distance between the pin holding portions 22. The pin 19 is inserted into the pin holding portion 22 so that both ends of the pin 19 protrude from the link 21 in the width direction, and the link 21 is connected in an annular shape. The link 21 and the pin 19 are configured to be able to rotate relative to each other.

  In the chain belt 6, a plurality of pins 19 may be inserted into the pin holding part 22 according to various conditions such as to improve rigidity, or the cross-sectional shape of the pin holding part 22 or the pin 19 is elliptical. You may form in various shapes. Specifically, the two pins 19 having an elliptical cross-sectional shape are inserted into the pin holding portion 22 in the same manner as a conventionally known chain belt. Moreover, while forming in a plane so that the surface where the two pins 19 oppose each other may be in surface contact, an inclined surface inclined in a direction away from a predetermined position is formed. In the chain belt in which the pin 19 formed in this way is inserted into the link 21, when the link 21 rotates, the two pins 19 relatively rotate so that the inclined surfaces come into contact with each other. The sliding resistance between the pin 19 and the pin 19 can be reduced.

  Further, it may be configured such that through holes are formed at both ends of the link 21 and the pins 19 are inserted into the through holes. That is, the shape or configuration of the pin 19 or the link 21 is not particularly limited. Furthermore, although the chain belt 6 has been described as an example here, for example, a so-called push belt in which a plurality of elements are stacked in the longitudinal direction and these elements are bound by an endless ring. Good.

  The CVT 1 configured as described above is configured to change the gear ratio by changing the gap between the first V-groove 11 and the second V-groove 17, and each conical surface 9, 10, 15, 16. And the chain belt 6, more specifically, the torque is transmitted by the frictional force between the conical surfaces 9, 10, 15, 16 and the end surface of the pin 19. That is, both end surfaces of the pin 19 are power transmission surfaces. An example of the control will be briefly described. By changing the amount of oil supplied to the first hydraulic actuator 12 according to the required gear ratio, the gear ratio is changed by changing the groove width of the first V groove 11. . Since the circumferential length of the chain belt 6 is constant, changing the groove width of the first V groove 11 inevitably changes the groove width of the second V groove 17 accordingly. Further, when the required driving force based on the accelerator opening degree changes and the torque to be transmitted changes, the hydraulic pressure supplied to the second hydraulic actuator 18 is changed to obtain the frictional force according to the transmitted torque. Thus, the clamping pressure for clamping the chain belt 6 is changed. That is, the transmission torque capacity is changed.

  In the CVT 1 that transmits the torque by the frictional force in this way, an inevitable slip occurs at a portion where each of the conical surfaces 9, 10, 15, 16 and the chain belt 6, more specifically, the end surface of the pin 19 contacts. Therefore, in this CVT 1, in order to improve the lubricity of the portion where the conical surfaces 9, 10, 15, 16 and the pin 19 are in contact with each other, oil is allowed to flow through the conical surfaces 9, 10, 15, 16. It is configured as follows. Specifically, as shown in FIG. 4, a cylindrical nozzle 23 that ejects oil toward the input shaft 2 and the output shaft 4 is provided in parallel to the input shaft 2 and the output shaft 4 and inside the chain belt 6. It has been.

  FIG. 5 is a schematic diagram for explaining an example of the configuration of the nozzle 23, and one end of the nozzle 23 is fixed to the case 24. Further, the nozzle 23 has a hollow portion 25 opened at an end fixed to the case 24, and an oil passage 26 is formed in the case 24 so as to communicate with the hollow portion 25. When the oil is supplied from the oil passage 26 to the hollow portion 25, the other end of the nozzle 23 is closed so that the oil is ejected to the input shaft 2 and the output shaft 4, and the axial direction is predetermined. A plurality of openings 27 are formed in the outer peripheral surface with a space therebetween. Therefore, oil that has flowed into the nozzle 23 via the case 24 is ejected from the opening 27 toward the input shaft 2 or the output shaft 4.

  The pulleys 3 and 5 are configured so that the oil jetted from the nozzle 23 to the input shaft 2 and the output shaft 4 as described above flows to the contact portions between the conical surfaces 9, 10, 15 and 16 and the pins 19. Has been. The configuration will be described with reference to the cross-sectional view shown in FIG. FIG. 1 shows a cross-sectional view of the primary pulley 3 when the largest gear ratio is set, that is, when the first movable sheave 8 is farthest from the first fixed sheave 7. The arrows in the figure indicate the flow of oil. Moreover, since the secondary pulley 5 can also be set as the substantially same structure as the primary pulley 3, the structure of the primary pulley 3 is demonstrated here.

  As described above, the primary pulley 3 includes the first fixed sheave 7 and the first movable sheave 8. Further, as shown in FIG. 1, a boss portion 28 protruding to the back side is integrally formed on the inner peripheral portion of the first movable sheave 8, and the boss portion 28 and the input shaft 2 are spline-engaged. At the same time, the first movable sheave 8 is slidably fitted to the input shaft 2. An oil passage 30 is formed so as to supply oil to the spline engaging portion 29 and the first hydraulic actuator 12. Specifically, a hollow portion 31 is formed from the end of the input shaft 2 opposite to the engine side along the rotation center axis of the input shaft 2, and the hollow portion 31 is formed on the outer peripheral surface of the input shaft 2. A plurality of through holes 32 and 33 are formed. More specifically, the hollow portion 31 is formed to a position substantially the same as the position of the first movable sheave 8 at the most distance from the first fixed sheave 7 in the axial direction of the input shaft 2, and the tip of the hollow portion 31 is formed. A plurality of first through holes 32 are formed in the portion at predetermined intervals in the circumferential direction, and at predetermined positions in the circumferential direction at substantially the same positions as the end portions of the boss portions 28. A plurality of second through holes 33 are formed.

  Spline teeth 34 are formed on the outer peripheral surface of the portion between the first through hole 32 and the second through hole 33 in the axial direction of the input shaft 2. Therefore, when oil is supplied to the hollow portion 31, the oil flows to the spline engaging portion 29 and a part of the oil is supplied to the fitting portion 35 between the first movable sheave 8 and the input shaft 2. It is configured to be.

  A cylinder 36 is provided so as to surround the back surface and the outer peripheral surface of the first movable sheave 8. The cylinder 36 is integrated with the input shaft 2 on the side opposite to the first through hole 32 with the second through hole 33 interposed therebetween. A seal member 37 is provided between the inner surface of the outer peripheral wall of the cylinder 36 and the first movable sheave 8. Therefore, a space is formed by the input shaft 2, the cylinder 36, and the first movable sheave 8, and the space is a hydraulic chamber 38. A third through hole 39 is formed in the boss portion 28 so as to supply oil to the hydraulic chamber 38. Specifically, a third through hole 39 is formed so as to communicate the spline engaging portion 29 and the hydraulic chamber 38. Therefore, when oil is supplied to the hydraulic chamber 38, the first movable sheave 8 is pressed toward the first fixed sheave 7 according to the hydraulic pressure. That is, the first movable sheave 8 is configured to function as a piston of the first hydraulic actuator 12.

  Further, the first fixed sheave 7 and the input shaft 2 are integrally formed by casting or the like, and an annular groove (hereinafter referred to as a corner cutting portion 40) is formed at a boundary portion between the first fixed sheave 7 and the input shaft 2. ) Is formed. When the first fixed sheave 7 receives a load from the chain belt 6 so that the groove width of the first V-groove 11 is widened, the corner cutout portion 40 stresses the boundary portion between the first fixed sheave 7 and the input shaft 2. It is formed to prevent the concentration from occurring. Therefore, as is known in the art, the shape of the corner cutout portion 40 is determined based on the load acting on the first fixed sheave 7, the rigidity of the first fixed sheave 7, etc. In the example shown in FIG. The cross-sectional shape is formed in a fan shape or a semicircular shape.

  Further, in the example shown in FIG. 1, a tapered portion 41 is formed on the input shaft 2. Specifically, a tapered portion 41 is formed from the corner cut portion 40 toward the first movable sheave 8 in the axial direction of the input shaft 2. In other words, the tapered portion 41 is formed between the first fixed sheave 7 and the first movable sheave 8. The tapered portion 41 is formed such that the outer diameter on the first movable sheave 8 side is larger than the outer diameter on the corner cutout portion 40 side. The tapered portion 41 corresponds to a guide portion when the present invention is implemented, and is formed so as to function as a guide for causing the oil to flow on the conical surface 9 when oil is sprayed on the input shaft 2. Has been. That is, the centrifugal force acts on the oil attached to the taper portion 41 due to the surface tension, so that the oil flows along the outer peripheral surface of the taper portion 41 toward the first movable sheave 8. Therefore, the input shaft 2 only needs to be formed with the tapered portion 41, and the length thereof is not limited. However, in order to cause a large amount of oil to flow on the conical surface 10, in other words, the oil flows on the conical surface 10. In order to prevent the oil from scattering from the input shaft 2 due to centrifugal force in the process, the portion of the taper portion 41 having the maximum outer diameter is the outer peripheral surface of the input shaft 2 and the first movable sheave 8. It is preferable to form so that it may be located in the location which contacts and fits with a surrounding surface. Specifically, the end of the first movable sheave 8 when the first movable sheave 8 is farthest from the first fixed sheave 7 and the end of the tapered portion 41 having the largest outer diameter are the input shaft 2. It is preferable to form up to the position where at least a part overlaps in the axial direction.

  In addition, the opening 27 of the nozzle 23 opens toward the corner cutout 40 in order to cause the oil to flow in the same manner also on the first fixed sheave 7 side. In other words, the opening 27 of the nozzle 23 is formed so that oil is sprayed to a portion of the input shaft 2 having the smallest outer diameter. Note that, regardless of which gear ratio is set, the first movable sheave 8 is closest to the first fixed sheave 7 so that oil is constantly sprayed to the input shaft 2. Also, the oil is ejected to a position that does not overlap the first movable sheave 8 in the axial direction. Moreover, in the example shown in FIG. 1, in order to make oil flow into the 1st movable sheave 8 and the 1st fixed sheave 7, it is comprised so that oil may be ejected toward the corner extraction part 40, but 1st When oil is allowed to flow only to the movable sheave 8, the oil may be ejected toward the tapered portion 41. Furthermore, it may be configured to eject oil to the tapered portion 14 and the corner cutout portion 40.

  Next, the flow of oil sprayed on the corner cutout 40 will be described. Part of the oil sprayed from the nozzle 23 to the corner cutout 40, more specifically, the oil attached to the first movable sheave 8 side in the axial direction than the deepest portion of the corner cutout 40 As described above, the fluid flows to the first movable sheave 8 side along the outer peripheral surface of the tapered portion 41 and then flows to the outer peripheral side along the conical surface 10 of the first movable sheave 8. As a result, the oil flows to the portion where the conical surface 10 of the first movable sheave 8 and the chain belt 6 are in contact with each other, whereby the lubricity of the contact portion can be improved.

  On the other hand, the oil adhering to the first fixed sheave 7 side in the axial direction than the deepest portion of the corner cutout portion 40 flows to the first fixed sheave 7 side. As described above, the corner cutout 40 is formed at the boundary portion between the first fixed sheave 7 and the input shaft 2, so that the oil that has flowed to the first fixed sheave 7 side remains as the cone of the first fixed sheave 7. It flows along the surface 9 toward the outer peripheral side. As a result, the oil flows to the portion where the conical surface 9 of the first fixed sheave 7 and the chain belt 6 are in contact with each other, whereby the lubricity of the contact portion can be improved.

  The oil flowing toward the first fixed sheave 7 and the first movable sheave 8 is sprayed more than the amount that can adhere to the input shaft 2 and the conical surfaces 9 and 10 of the sheaves 7 and 8. The oil is scattered to the outer peripheral side by centrifugal force. The scattered oil flows in the chain belt 6 from the inner peripheral side to the outer peripheral side of the chain belt 6. As a result, the link 21 and the pin 19 can be lubricated, or the chain belt 6 can be cooled.

  Further, as described above, when the portion of the taper portion 41 having the largest outer diameter is formed so as to be in a position where the outer peripheral surface of the input shaft 2 and the first movable sheave 8 come into contact with each other. The oil flowing along the taper portion 41 can be prevented from being scattered to the outer peripheral side by centrifugal force before reaching the first movable sheave 8. Therefore, it can suppress that the oil quantity which flows through the 1st movable sheave 8 falls. In addition, after oil is stored in a portion sandwiched between the outer peripheral surface of the tapered portion 41 and the inner peripheral surface of the first movable sheave 8, the oil is collected between the outer peripheral surface of the tapered portion 41 and the inner peripheral surface of the first movable sheave 8. No more oil is stored in the sandwiched portion. Therefore, after the oil is stored in the portion, all of the oil flowing through the tapered portion 41 is directed toward the conical surface 10 of the first movable sheave 8. Fluid. As a result, it is possible to suppress a decrease in the amount of oil flowing through the conical surface 10, so that the lubricity of the portion where the conical surface 10 of the first movable sheave 8 and the chain belt 6 are in contact can be improved. it can.

  Furthermore, since the first movable sheave 8 is fitted to the input shaft 2 as described above, a part of the oil supplied to the spline engaging portion 29 or the first hydraulic actuator 12 is connected to the first movable sheave 8. It leaks from the fitting part 35 with the input shaft 2 to the first V-groove 11 side. The oil thus leaked flows along the conical surface 10 of the first movable sheave 8 together with the oil sprayed on the input shaft 2. Therefore, the lubricity of the contact portion between the conical surface 10 of the first movable sheave 8 and the chain belt 6 can be further improved.

  As described above, the secondary pulley 5 is configured similarly to the primary pulley 3. Accordingly, the secondary pulley 5 is also formed with a corner cut portion and a tapered portion. Therefore, oil flows along the conical surface 16 of the second movable sheave 14 and the conical surface 15 of the second fixed sheave 13. As a result, the lubricity of the contact portions between the conical surfaces 15 and 16 and the chain belt 6 can be improved in the same manner as the primary pulley 3 described above.

  As described above, in order to supply oil to each of the conical surfaces 9, 10, 15, 16, the oil sprayed from the outer peripheral side of the input shaft 2 or the output shaft 4 is caused by centrifugal force to cause the tapered portion 41 and the conical surface 9. , 10, 15 and 16. Therefore, since the load which inhibits the flow of the oil does not act on the oil, it is possible to suppress a decrease in the amount of oil flowing through each of the conical surfaces 9, 10, 15 and 16. As a result, the lubricity of the contact portion between each conical surface 9, 10, 15, 16 and the chain belt 6 can be improved.

  Moreover, what is necessary is just to spray oil on the input shaft 2 or the output shaft 4 as mentioned above. Therefore, the input shaft 2 and the output shaft 4 are prevented from lowering the rigidity of the input shaft 2 and the output shaft 4 by forming through holes for supplying oil to the conical surfaces 9, 10, 15, 16 in the input shaft 2 and the output shaft 4, for example. Or the occurrence of stress concentration can be suppressed. As a result, when the sheaves 7, 8, 13, and 14 receive a load from the chain belt 6, the input shaft 2 and the output shaft 4 are prevented from being bent and the groove widths of the V-grooves 11 and 17 are suppressed. It can suppress that the durability of the input shaft 2 or the output shaft 4 falls.

  Further, in the CVT 1 configured as described above, the surface pressure acting on each of the conical surfaces 9, 10, 15 and 16 changes according to the gear ratio. FIG. 6 is a diagram showing changes in the surface pressure acting on the respective conical surfaces 9, 10, 15 and 16 in accordance with the gear ratio, with the horizontal axis indicating the gear ratio and the vertical axis indicating the surface pressure. A solid line indicates a change in surface pressure acting on the first fixed sheave 7 and the first movable sheave 8, and a broken line indicates a change in surface pressure acting on the second fixed sheave 13 and the second movable sheave 14. As shown in FIG. 6, when the gear ratio is small, the winding radius of the chain belt 6 wound around the primary pulley 3 is increased, and the winding radius of the chain belt 6 wound around the secondary pulley 5 is decreased. Therefore, the contact area between the first fixed sheave 7 and the first movable sheave 8 and the chain belt 6 is increased, so that the surface pressure acting on the first fixed sheave 7 and the first movable sheave 8 is reduced. On the contrary, since the contact area between the second fixed sheave 13 and the second movable sheave 14 and the chain belt 6 is reduced, the surface pressure acting on the second fixed sheave 13 and the second movable sheave 14 is increased.

  On the other hand, when the gear ratio is large, the winding radius of the chain belt 6 wound around the primary pulley 3 is reduced, and the winding radius of the chain belt 6 wound around the secondary pulley 5 is increased. Therefore, the contact area between the first fixed sheave 7 and the first movable sheave 8 and the chain belt 6 is reduced, so that the surface pressure acting on the first fixed sheave 7 and the first movable sheave 8 is increased. On the contrary, since the contact area between the second fixed sheave 13 and the second movable sheave 14 and the chain belt 6 is increased, the surface pressure acting on the second fixed sheave 13 and the second movable sheave 14 is reduced. Further, when the gear ratio is large, the torque transmitted to the secondary pulley 5 is increased, so that the clamping pressure is controlled to increase according to the torque. Therefore, the surface pressure acting on the first fixed sheave 7 and the first movable sheave 8 when the gear ratio is larger than the surface pressure acting on the second fixed sheave 13 and the second movable sheave 14 when the gear ratio is small. growing.

  Further, as the taper angle θ of the taper portion 41 (angle formed by the rotation center axis and the outer peripheral surface of the taper portion) is increased, the flow velocity of the oil flowing through the taper portion 41 is increased. This is because the flow direction of the oil flowing through the taper portion 41 and the direction in which the centrifugal force acts on the oil approach. Therefore, as the taper angle θ is increased, the flow rate of the oil flowing to the conical surface 10 (16) can be increased, so that the lubricity between the conical surface 10 (16) and the chain belt 6 can be improved. it can.

  Therefore, in this CVT 1, the taper angle θ of the taper portion 41 formed on the input shaft 2 is set to the taper formed on the output shaft 4 in order to improve the lubricity of the first fixed sheave 7 and the first movable sheave 8. It is formed larger than the taper angle of the part.

  In this way, the taper angle θ of the taper portion 41 formed on the input shaft 2 is made larger than the taper angle of the taper portion formed on the output shaft 4, thereby allowing the conical surface 10 of the first movable sheave 8 to flow. The amount of oil can be increased, and the lubricity of the contact portion between the conical surface 10 and the chain belt 6 can be improved. In addition, by reducing the taper angle of the tapered portion formed on the output shaft 4, it is possible to suppress a decrease in rigidity of the output shaft 4 due to the formation of the tapered portion.

  In the above-described example, the first fixed sheave 7 is formed integrally with the input shaft 2. However, the first fixed sheave 7 and the input shaft 2 are formed of different members, and the first fixed sheave 7 and the input shaft 2 are input. The shaft 2 may be integrally connected. As described above, when the first fixed sheave 7 and the input shaft 2 are formed of different members and the first fixed sheave 7 and the input shaft 2 are integrally connected, the corner cutting portion 40 is not necessary. For this reason, a portion where the outer diameter gradually increases is formed on the input shaft 2 so as to guide the oil blown to the input shaft 2, and the oil may be ejected toward at least one of the portions. Further, in order to allow the oil to flow through the first fixed sheave 7 and the first movable sheave 8, a portion where the outer diameter gradually increases as it moves away from both sides in the axial direction is formed. What is necessary is just to comprise so that oil may be sprayed to a location with a small diameter. Further, the output shaft 4 and the second fixed sheave 13 can be formed in the same manner.

  Further, in the above-described example, the taper portion 41 is formed on the input shaft 2 and the output shaft 4 so as to guide the oil flow, but the outer diameter gradually increases. It is only necessary to form a portion that becomes larger, and the shape is not limited to the tapered shape.

  In the above-described example, the first movable sheave 8 and the second movable sheave 14 are configured to be pressed by the hydraulic actuators 12 and 18, but other mechanisms such as an electromagnetic actuator and a torque cam are provided. You may be comprised so that it may press. In that case, the oil that lubricates the fitting portion between the first movable sheave 8 and the input shaft 2 or the second movable sheave 14 and the output shaft 4 leaks into the first V groove 11 or the second V groove 17. It is preferable to configure.

  DESCRIPTION OF SYMBOLS 1 ... Belt type continuously variable transmission (CVT), 2 ... Input shaft, 3 ... Primary pulley, 4 ... Output shaft, 5 ... Secondary pulley, 6 ... Chain belt, 7, 13 ... Fixed sheave, 8, 14 ... Movable sheave 9, 10, 15, 16 ... conical surface, 11, 17 ... V groove, 12, 18 ... hydraulic actuator, 19 ... pin, 20 ... connecting hole, 21 ... link, 22 ... pin holding part, 23 ... nozzle, 35 ... Fitting part, 40 ... Corner part, 41 ... Taper part.

Claims (9)

A pair of pulleys each having a fixed sheave integrated with the rotating shaft and a movable sheave fitted to the rotating shaft so as to rotate integrally with the rotating shaft and move in the axial direction of the rotating shaft And a belt-type continuously variable transmission comprising a belt wound around the pair of pulleys and transmitting torque,
Of the outer periphery of the rotating shaft, a portion between the sheaves is a guide portion whose outer diameter gradually increases toward at least one of the sheaves,
A belt-type continuously variable transmission comprising a nozzle portion that ejects oil that lubricates a contact portion between each sheave and the belt toward at least one of the guide portions. The maximum outer diameter of the guide portion is formed smaller than the inner diameter of the movable sheave,
The portion of the guide portion having the largest outer diameter is configured to be located at a portion of the outer peripheral portion of the rotating shaft where the movable sheave contacts and fits. The belt-type continuously variable transmission according to 1. The rotating shaft and the fixed sheave are integrally formed,
The rotating shaft is formed with an annular groove for reducing the stress concentration generated when the fixed sheave receives a load from the belt,
The belt-type continuously variable transmission according to claim 1 or 2, wherein the guide portion is formed in a shape in which an outer diameter gradually increases from the annular groove toward the movable sheave.   The belt-type continuously variable transmission according to claim 3, wherein the nozzle portion is configured to inject the oil toward the annular groove. The fixed sheave has a conical surface that faces the movable sheave in the axial direction of the rotation shaft,
The said guide part is formed in the shape where an outer diameter increases gradually toward the said movable sheave side from the location where the said fixed sheave and the said rotating shaft were connected. The belt type continuously variable transmission according to any one of the above. A hydraulic actuator that applies hydraulic pressure to the back surface of the movable sheave so as to move the movable sheave in the axial direction of the rotation shaft;
2. A part of oil supplied to the hydraulic actuator is configured to leak from a fitting part between the movable sheave and the rotating shaft and flow to the guide part. 5. The belt type continuously variable transmission according to any one of 5 above.   Part of the oil supplied so as to lubricate the fitting portion between the movable sheave and the rotating shaft leaks from the fitting portion between the movable sheave and the rotating shaft and flows to the guide portion. The belt-type continuously variable transmission according to any one of claims 1 to 6, wherein the belt-type continuously variable transmission is configured. A rotating shaft provided on one of the pair of pulleys receives torque from a power source,
The rotating shaft provided on the other pulley of the pair of pulleys transmits torque to the output member,
The rotating shaft provided in the one pulley and the rotating shaft provided in the other pulley have the guide portion,
The angle formed between the outer peripheral surface of the guide portion on the rotary shaft provided on the one pulley and the central axis of the rotary shaft is such that the outer peripheral surface of the guide portion on the rotary shaft provided on the other pulley and the rotary shaft. The belt-type continuously variable transmission according to any one of claims 1 to 7, wherein the belt-type continuously variable transmission is formed to be larger than an angle formed by the central axis.   The belt is fitted with a plurality of plate-like links, a coupling hole formed in the link, and the links are connected in an annular shape, and both end surfaces in the axial direction are in contact with the sheaves and a power transmission surface. A belt type continuously variable transmission according to any one of claims 1 to 8, further comprising a chain belt provided with a pin.

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