JPH10213198A - Pulley mounting part structure of belt type continuously variable transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent grease flow easily leaking by providing a key groove with a space in the groove which forms a grease flow passage between an inner face of the key groove of a movable sieve and a key and flowing grease which is collected in it in the key groove due to the slide of the sieve. SOLUTION: Grease is collected in a grease chamber 18 provided with a plug member 23 on one end side of an input shaft 3, and grease is supplied to each key groove 15 in a plurality of sections through an oil supply passage 19 and a grease collection groove 16 from the grease chamber 18. At the time of gear shift, a movable sieve 4b slides smoothly due to grease. At this time, the grease in a groove part on a side where an internal space of the key groove 15 is narrowed flows into a grease flow passage 22 due to the pressing action of a key 5 and the relative travel of the movable sieve 4b and the key 5 and travels toward a groove part on a side where the internal space of the key groove 15 becomes wide. Consequently, the grease in the key groove 15 is pressurized by the key 5 so that a leakage of the grease which is pushed out to the outside of the key groove 15 from between a seal material 17 and an input shaft 3 does not occur easily.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a belt-type continuously variable transmission in which a movable sheave of a split pulley and a rotating shaft for slidably supporting the movable sheave are integrally rotatably engaged by a key. And a pulley mounting structure.

[0002]

2. Description of the Related Art In the above belt-type continuously variable transmission,
Since the movable sheave and the rotary support shaft are integrally rotatably engaged with each other by the key, power can be transmitted more advantageously than when the ball is engaged. That is, when the movable sheave and the rotation support shaft engage with each other with a ball, the movable sheave and the rotation support shaft transmit or receive rotational power by point contact with the ball. On the other hand, when the movable sheave and the rotation support shaft engage with each other with the key, the movable sheave and the rotation support shaft transmit or receive the rotational power by surface contact with the key. Therefore, when the movable sheave and the rotation support shaft are engaged with each other by a key, deformation and distortion are less likely to occur in the movable sheave and the rotation support shaft.

[0003]

In general, when a movable sheave and a rotary support shaft are engaged with a key by a key, the key is slidably inserted into a key groove of the movable sheave. However, due to the engagement flexibility, a gap through which the grease flows easily between the key and the movable sheave cannot be obtained. For this reason, if grease is stored in the key groove so that the movable sheave slides smoothly with respect to the rotating spindle, the key presses the grease as the movable sheave slides during shifting, and the grease is removed. There was a case where the gas leaked from a seal portion between the movable sheave and the rotating shaft. In particular, when the movable sheave is configured to be slid by the driving force of the speed change drive mechanism, and the movable sheave is slid at a relatively high speed, leakage tends to occur. When the grease leaks to the side where the power transmission belt is located, the grease may adhere to the belt winding side surface of the pulley or the belt and induce slip. SUMMARY OF THE INVENTION It is an object of the present invention to provide a belt-type continuously variable transmission that can use a keyway for storing grease while preventing grease leakage due to sliding of a movable sheave.

[0004]

The constitution, operation and effect of the invention according to claim 1 are as follows.

[Structure] A pulley mounting portion structure of a belt type continuously variable transmission in which a movable sheave of a split pulley and a rotation support shaft slidably supporting the movable sheave are integrally rotatably engaged by a key. In the above, the groove inside the key groove of the movable sheave is provided with a space inside the key groove of the movable sheave to form a grease flow path between the key and the grease stored in the key groove. It is configured to flow from one end of the key groove to the other end through the grease flow path with movement.

[Operation] When grease is stored in the key groove and the movable sheave is slid, the movable space between one end and the other end of the key groove moves relative to the key. The grease located in the groove portion on the side where is narrowed is provided with a fluid force by the pressing action of the key. Then, the grease flows into the grease flow path, and moves toward the groove portion on the side where the internal space becomes wider between the one end portion and the other end portion of the key groove. Thus, grease stored in the key groove is less likely to be leaked by being pressed by the key and being pushed out of the seal portion between the movable sheave and the rotary shaft to the outside.

[Effect] Even if grease is stored in the key groove, grease leakage due to shifting can be avoided by the grease flow path, so that the movable sheave can be smoothly slid by a simple structure using the key groove as a grease pool. The transmission can be performed smoothly, and transmission can be performed while avoiding transmission failure such as slippage due to grease leakage.

The structure, operation and effect of the invention according to claim 2 are as follows.

[Constitution] In the constitution according to the first aspect of the invention, the grease flow path is formed between a bottom surface portion of the inner surface of the key groove and the key.

[Operation] Even if the grease flow path is formed between the side surface of the key groove inner surface and the key, the grease is moved from one end to the other end of the key groove as the movable sheave slides. However, in this case, a large engagement and fusion between the key and the movable sheave occurs due to the space in the key groove forming the grease flow path, and the rotation between the movable sheave and the rotating shaft is performed. Large backlash occurs in the moving direction. On the other hand, according to the invention described in claim 2, since the grease flow path is formed between the key and the bottom surface of the key groove inner surface, the gap between the movable sheave and the key caused by the grease flow path is formed. The grease flow path can be provided while preventing rattling in the rotating direction, and the movable sheave and the rotating support shaft smoothly rotate integrally so as to prevent rattling.

[Effect] In the case of providing the grease flow path, the movable sheave and the rotary support shaft smoothly rotate integrally with each other, so that the key groove is used as a grease reservoir so that the gear can be smoothly shifted while avoiding grease leakage. However, even if the input rotation speed becomes uneven or changed, vibration and noise are hardly generated, and the gear can be shifted quietly and smoothly from this aspect.

The structure, operation and effect of the invention according to claim 3 are as follows.

[Structure] In the structure of the invention according to claim 1 or 2, the movable sheave is slid by the driving force of a speed change drive mechanism.

[Operation] When the speed change drive mechanism is started, the speed change drive mechanism slides the movable sheave to change the speed.
As a result, even if the speed change drive mechanism is driven at a high speed and the movable sheave slides at a high speed, the grease flows smoothly through the grease flow path through the grease flow path even if the grease pressurizing speed by the key increases. It will be hard to leak out.

[Effects] The transmission is changed to a state of good transmission so that transmission failure due to grease leakage is unlikely to occur, and the speed can be changed by a light operation only to start the speed change drive mechanism. It is possible to obtain a state of good shifting performance that can be quickly shifted by sliding.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a rotational output of an engine E is transmitted to an input belt pulley 1 of a belt-type continuously variable transmission H via a belt tension clutch C. The rotation output is transmitted to the pair of left and right crawler traveling devices A via the traveling mission M, and the rotational power of the output shaft M1 of the traveling mission M is transmitted to the reaper K to transmit the power of the combine. The structure is configured.

The belt-type continuously variable transmission H is configured as shown in FIGS. That is, as clearly shown in FIG. 2, an input shaft 3 to which the input belt pulley 1 is integrally rotatably connected to one end is rotatably supported at one end of the transmission case 2. A sheave 4a integrally molded on one end of the inner portion of the case, and a sheave 4b mounted on the other end so as to be slidable in the axial direction of the input shaft 3 and engageable with the input shaft 3 by a key 5 so as to be integrally rotatable. Split pulley 4 that rotates integrally with input shaft 3
Is configured. At the other end of the transmission case 2, a spline shaft end 6a for outputting to the traveling mission M rotatably supports an output shaft 6 located at one end,
The output shaft 6 is integrally rotated with the output shaft 6 by a sheave 7a integrally molded on one end side of a portion inside the transmission case and a sheave 7b mounted on the other end side so as to be slidable in the axial direction of the output shaft 6. A split pulley 7 is formed.

The transmission belt 9 is wound around the split pulley 4 on the input side and the split pulley 7 on the output side, and the transmission belt 9 is formed by a tension spring 10 composed of a coil spring attached to the boss portion of the sheave 7b of the output side split pulley 7. The transmission belt 9 and the split pulleys 4 and 7 are provided with a transmission tension to give a frictional force between the transmission belt 9 and the split pulleys 4 and 7 to rotate integrally. That is, one end of the tension spring 10 abuts against the outer side surface of the sheave 7 b of the split pulley 7, and the other end thereof is connected to the output shaft 6.
Is in contact with the spring receiving body 11 which is fitted to the outside. The spring receiving body 11 is supported by the output shaft 6 so as to be able to rotate only integrally by spline engagement with the output shaft 6. The sheave 7b is fitted to the output shaft 6 so as to be relatively rotatable, and a cam mechanism 12 is provided between the sheave 7b and the spring receiving body 11.
Is provided. The cam mechanism 12 is configured to integrally rotate the sheave 7b with the output shaft 6 by engaging the sheave 7b and the spring receiving body 11 so as to rotate together. Further, the sheave 7b is slid toward the sheave 7a in proportion to an increase in the driving load applied to the output shaft 6. Therefore, the tension spring 10
The movable sheave 7b slidably supported on the output shaft 6 of the pair of sheaves 7a and 7b of the split pulley 7 as a reaction force member with the spring receiving body 11 as a reaction force member is supported on the output shaft 6 so as to be able to rotate only integrally therewith. The transmission belt 9 is slidably urged toward the fixed-side sheave 7a to urge the belt winding diameter of the split pulley 7 toward the enlarged side to apply a tension to the transmission belt 9.

As shown in FIGS. 2 and 3, the boss portion of the movable sheave 4b slidably supported on the input shaft 3 of the pair of sheaves 4a and 4b of the input split pulley 4 has a bearing. And a roller 32 rotatably mounted via a support shaft 32a on a plurality of outer peripheral surfaces of the pulley operating body 31 in a circumferential direction of the pulley operating body 31, which is rotatably supported via An operation cylinder 33 having a cam portion 33a acting on the roller 32 as shown in FIG. 5 at one end side and being rotatably attached to the cylindrical portion 2a of the transmission case 2 around the axis X of the input shaft 3 is provided. A fan-shaped operation gear 34, which is integrally rotatably mounted on the outer peripheral surface of the cylindrical body 33 located outside the transmission case 2, an electric transmission motor 35 in which an output gear 35a meshes with the operation gear 34, and a transmission motor 35. Link A pair of switches S1 and S2 attached to the operation gear 34, an operation arm 36 for the switches S1 and S2 are provided, and the attachment cylinder 37a allows the operation cylinder 33 to be relatively rotatable toward the outer peripheral surface side of the operation cylinder 33. The gearshift operating mechanism 30 is constituted by each of the gearshift levers 37 attached.

The speed change motor 35 is mounted on a bracket 38 supported by the speed change case 2. The pulley operating body 31 is connected to the input shaft 3 by a bearing positioned between the pulley operating body 31 and the boss portion of the sheave 4b, and a bearing stopper ring for locking the bearing to the sheave 4b and the pulley operating body 31. Sheave 4b in the direction of the axis X
Move with.

As shown in FIG. 3, an operation lever 42 interlocked by an operation cable 41 with an operation valve V of a hydraulically operated forward / reverse switching device (not shown) provided in the traveling mission M, and a transmission case 2 is provided. The supporting bracket 43 is swingably supported. This operation lever 4
A forward / reverse switching cam 44 having a cam groove 44a slidably engaged with the free end of the second gear 2 is rotatably attached to the operation gear 34 so that the speed change motor 35 can rotate the operation gear 34. Accordingly, the forward / reverse switching cam 44 rotates together with the operation gear 34 to swing the operation lever 42, and switches the operation valve V via the operation cable 41, thereby switching the forward / backward switching device to the forward side and the reverse side. , Or to switch to a neutral state in which transmission is stopped. Thereby, the switching operation of the forward / reverse switching device by the shift lever 37 is enabled.

That is, the speed change lever 37 is supported by the mounting cylinder portion 37a so as to be swingable about the axis Y, and the direction of the swing around the axis Y and the axis X of the input shaft 3 is changed. And the rocking operation is performed along a lever guide groove G shaped as shown in FIG. Then, when the shift lever 37 is operated to the neutral position N shown in FIG. 4, the forward / reverse switching device enters a neutral state, and the driving of the left and right crawler traveling devices A, A can be stopped. When the shift lever 37 is operated in the forward range F, the forward / reverse switching device is switched to the forward side, and the left and right crawler traveling devices A, A can be driven in the forward direction. And the left and right crawler traveling devices A, A can be driven to the reverse side.

When the shift lever 37 is positioned in the forward movement range F and the shift lever 37 is swung in a direction away from the neutral position N, the switch operating arm 36 swings in the swing direction shown in FIG. f and the operating gear 3
The switch S1 of the pair of switches S1 and S2 is pressed by the operation pin portion 36a inserted into the through hole of No. 4. Then, the switch S1 is turned on to drive the transmission motor 35 in the forward rotation direction, and the transmission motor 35 rotates the operation gear 34 in the rotation direction f to rotate the operation cylinder 33. The operating cylinder 33 is a cam 33a.
The pulley operating body 31 is pressed via the roller 32 with the inclined cam surface 33b shown in FIG.
To increase the belt winding diameter of the split pulley 4. At this time, as the movement stroke of the shift lever 37 from the neutral position N is increased, the operating speed of the shift motor 35 is increased, and the operating cylinder 33 moves the roller 32 to the top of the inclined cam surface 33b. In order to increase the sliding stroke of the sheave 4b, the belt winding diameter of the split pulley 4 increases. On the contrary, the shift lever 37 is moved to the neutral position N
When the rocking operation is performed in a direction approaching the direction, the switch operating arm 36 is rocked in the rocking direction r shown in FIG. 3 due to the lever operating force, and the switch of the pair of switches S1 and S2 is operated by the operating pin portion 36a. The user presses S2.
Then, the switch S2 is turned on and the transmission motor 3
5 is driven in the reverse rotation direction, the transmission motor 35 rotates the operation gear 34 in the rotation direction r to rotate the operation cylinder 33, and the operation cylinder 33 causes the roller 32 to move the roller 32 to the inclined cam surface 33.
b, the sheave 4b is slid in the direction away from the sheave 4a by the tension of the transmission belt 9 to reduce the belt winding diameter of the split pulley 4. At this time, as the shift lever 37 is moved closer to the neutral position N, the operating rotation speed of the shift motor 35 is increased, and the operating cylinder 33 moves the roller 32 closer to the bottom end side of the inclined cam surface 33b, so that the sheaves 4b and 4
In order to increase the interval between the split pulleys 4a and 4a, the winding diameter of the belt of the split pulley 4 is reduced.

When the shift lever 37 is located in the reverse range R, when the shift lever 37 is operated to swing away from the neutral position N, the switch operating arm 36 swings in the swing direction r due to the lever operating force. And the operation pin portion 36a
Switch S of the pair of switches S1 and S2
2 is pressed. Then, the switch S2 is turned on to drive the transmission motor 35 in the reverse rotation direction, and the operation gear 34 is rotated in the rotation direction r to rotate the operation cylinder 33, whereby the operation cylinder 33 is rotated. Is the cam part 33a
The pulley operating body 31 is pressed via the roller 32 with the inclined cam surface 33c shown in FIG.
To increase the belt winding diameter of the split pulley 4. At this time, as the movement stroke of the shift lever 37 from the neutral position N is increased, the operation speed of the shift motor 35 is increased, and the operating cylinder 33 moves the roller 32 to the top of the inclined cam surface 33c. In order to increase the sliding stroke of the sheave 4b, the belt winding diameter of the split pulley 4 increases. On the contrary, the shift lever 37 is moved to the neutral position N
When the rocking operation is performed in a direction approaching the switch operation arm 36, the switch operating arm 36 is rocked in the rocking direction f due to the lever operating force, and a pair of switches S1 and S2 are operated by the operation pin portion 36a.
Of the switch S1 is pressed. Then, the switch S1 is turned on to drive the speed change motor 35 in the forward rotation direction, and the operation gear 34 is rotated in the rotation direction f to rotate the operation cylinder 33, whereby the operation cylinder 33 is rotated. The roller 33 moves the roller 32 to the bottom side of the inclined cam surface 33c to slide the sheave 4b away from the sheave 4a by the tension of the transmission belt 9, thereby reducing the belt winding diameter of the split pulley 4. At this time, the shift lever 37 is moved to the neutral position N
, The operation rotation speed of the speed change motor 35 increases, and the operating cylinder 33 moves the roller 32 closer to the bottom end side of the inclined cam surface 33c to increase the distance between the sheave 4b and the sheave 4a. The belt winding diameter of the pulley 4 is reduced.

When the shift lever 37 is operated in either the forward range F or the reverse range R, or in any direction of moving away from or approaching the neutral position N, the speed is changed. When the lever 37 is stopped at a desired operating position and the switches S1 and S2 are separated from the operation pin portion 36a as the transmission motor 35 rotates the operation gear 34, the switches S1 and S2 return to the off state and the transmission motor 35
To stop. As a result, the sliding operation of the sheave 4b by the operation cylinder 33 is stopped, and the belt winding diameter of the split pulley 4 is maintained at a size corresponding to the operation position of the shift lever 37. Then, the sheave 4 is formed on the split pulley 4 on the input side.
When the operation position of b is determined and the belt winding diameter is determined, the belt winding diameter of the output side split pulley 7 has a size corresponding to the belt winding diameter of the input side split pulley 4 due to the tension of the transmission belt 9. , And the rotation speed of the output shaft 6 becomes a speed corresponding to the operation position of the shift lever 37.

That is, when moving forward, the shift lever 37 is swung in a direction away from the neutral position N to turn on the switch S1, and when the vehicle is moving backward, the shift lever 37 is swung in a direction away from the neutral position N. Switch S2 is turned on. Then, the switches S1 and S2 are set to the speed change motor 3
5, the movable sheave 4b of the input side split pulley 4 is slid toward the fixed sheave 4a by the driving force of the transmission motor 35 to change the belt winding diameter of the input side split pulley 4 to the enlarged side. Then, the movable sheave 7b of the output split pulley 7 is slid in a direction away from the fixed sheave 7a by the tension of the transmission belt 9 to change the belt winding diameter of the output split pulley 7 to the reduction side. As a result, the rotation speed of the output shaft 6 changes to a higher speed than before the speed change operation.

When moving forward, the shift lever 37 is moved to the neutral position N
The switch S2 is turned on by swinging in the direction approaching the position. When the vehicle is moving backward, the shift lever 37 is swung in the direction approaching the neutral position N to turn on the switch S1. Then, the switches S1 and S2 start the speed change motor 35, and slide the movable sheave 4b of the input side split pulley 4 away from the fixed sheave 4a by the tension of the transmission belt 9 to wind the belt of the input side split pulley 4. Change the diameter to the reduction side,
The movable sheave 7b of the output split pulley 7 is slid toward the fixed sheave 7a by the operating force of the tension spring 10 to change the belt winding diameter of the output split pulley 7 to the enlarged side.
As a result, the rotation speed of the output shaft 6 changes to a lower speed than before the speed change operation.

As shown in FIGS. 6 and 7, the input side split pulley 4 is positioned between the boss portion 4c of the movable sheave 4b and the input shaft 3 so as to rotate the two 4c and 3 together. The keys 5 to be combined are provided at a plurality of locations in the circumferential direction of the boss 4c. The lower end of each key 5 enters the key hole of the input shaft 3 and is immovably fixed to the input shaft 3, and the upper end exposed to the boss portion 4 c from the key hole of the input shaft 3 of each key 5. The side slidably enters a key groove 15 formed on the inner peripheral surface side of the boss 4c along the longitudinal direction of the boss 4c. A grease reservoir groove 16 formed so as to communicate with the plurality of key grooves 15 and shallower than each key groove 15, and a boss portion 4c at both ends of the boss portion 4c.
And a seal member 17 for sealing the space between the key shaft 15 and the input shaft 3 to prevent the leakage of grease from the key groove 15.
a grease chamber 18 provided on the inner peripheral surface side of c and formed by drilling a shaft core of the input shaft 3 from one end side;
The input shaft 3 is provided with an oil supply passage 19 for communicating the grease chamber 18 with a portion of the grease reservoir groove 16 located between the key grooves. Each of the plurality of key grooves 15 is formed as shown in FIGS. That is, even when the movable sheave 4b is operated to any operation position in the operation area where the sliding operation is performed, there is a gap between the side surface portion 20 of the inner surface of the key groove 15 and the side surface of the key 5. Engagement flexibility is formed such that the key 5 is slidably inserted into the key groove 15, and the bottom portion 21 of the inner surface of the key groove 15 is formed.
A grease flow path 22 is formed between the key groove 5 and the upper surface 5a of the key 5 to allow grease in the key groove to flow over the key 5 to one end and the other end of the key groove 15. It is formed to have a sufficient space in the groove.

That is, the grease chamber 18 includes a plug member 23 made of a bolt attached to one end of the input shaft 3 and an air vent hole 23a formed in the plug member 23.
Grease is supplied to the grease chamber 18 and stored therein by injecting the grease from the oil supply port of the grease, and grease is supplied from the grease chamber 18 to each key groove 15 through the oil supply passage 19 and the grease accumulation groove 16. Then, during shifting, the movable sheave 4b is smoothly slid by the lubrication of the grease. At this time, the movable sheave 4b of the one end portion and the other end portion of the key groove 15
The grease located in the groove portion on the side where the internal space is narrowed by the relative movement between the key 5 and the key 5 is given a fluid force by the pressing action of the key 5. Then, the grease flows into the grease flow path 22 and moves toward the groove portion on the side where the internal space becomes wider between the one end portion and the other end portion of the key groove 15. As a result, the grease in the key groove is pressed by the key 5 and the seal material 17 and the input shaft 3 are pressed.
Grease leaked out of the keyway from between the above and the like is less likely to occur.

As shown in FIG. 2, the split pulley 4 on the input side
Auxiliary spring 13 composed of a coil spring exerting a smaller elastic restoring force than the tension spring 10 on the boss portion of the movable sheave 4b.
Is attached. One end of the auxiliary spring 13 is in contact with a bear rig stop ring that locks a bearing between the operating cylinder 33 and the boss of the movable sheave 4b, and the other end is
A bearing located between the cylindrical portion 2a of the transmission case 2 and the input shaft 3 is in contact with a spring receiver 14 received and supported, and the auxiliary spring 13 moves the movable sheave 4b toward the fixed sheave 4a. The sliding belt is pressed against the transmission belt 9. That is, when the input to the transmission is stopped and the rotation of the split pulley 4 is stopped, the shift lever 37 is stopped.
Is operated to the deceleration side, the operation cylinder 33 is moved to the speed change motor 35.
Therefore, even if the movable sheave 4b is rotated to a position corresponding to the operation position of the transmission lever 37, the movable sheave 4b is not moved and remains at the original position before the operation of the transmission lever. After that, when the split pulley 4 starts rotating by being input to the transmission, the transmission belt 9 is pressed against the pulley 4 for the auxiliary spring 13 and starts rotating together with the pulley 4. This allows the movable sheave 4b to be moved by the transmission belt 9 without returning the transmission lever 9 to the original operation position on the high-speed side and sliding the movable sheave 4b to press the transmission belt 9 against the pulley 4. The transmission lever 37 is slid to the position corresponding to the operation position on the deceleration side of the shift lever 37 operated when the input is stopped, and transmission is performed at the speed corresponding to this operation position.

[Another Embodiment] Input shaft 3 and movable sheave 4b
The present invention can be applied to a case where the output shaft 6 and the movable sheave 7b are integrally rotatably engaged with each other by a key, in addition to a case where the output shaft 6 and the movable sheave 7b are integrally rotatably engaged by a key. Therefore, the input shaft 3 and the output shaft 6 are referred to as a rotation support shaft.

The present invention can also be applied to a case where a hydraulic cylinder or the like is used instead of the speed change motor 35 and the movable sheave 4b is configured to slide. Therefore,
The transmission motor 35 and the hydraulic cylinder are collectively referred to as a transmission drive mechanism.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a transmission structure of a combine.

FIG. 2 is a sectional view of a belt-type continuously variable transmission.

FIG. 3 is a side view of a speed change operation unit.

FIG. 4 is an explanatory diagram showing an operation position of a shift lever.

FIG. 5 is an explanatory view of a cam portion of the operation cylinder.

FIG. 6 is a sectional view of a movable sheave mounting portion.

FIG. 7 is a cross-sectional view of the input shaft and the movable sheave in a key arrangement portion.

[Explanation of symbols]

 Reference Signs List 3 Rotating support shaft 4 Split pulley 4b Movable sheave 5 Key 15 Key groove 21 Bottom part 22 Grease flow path 35 Speed change drive mechanism

Claims (3)

[Claims] 1. A pulley mounting portion structure for a belt-type continuously variable transmission in which a movable sheave of a split pulley and a rotation support shaft slidably supporting the movable sheave are integrally rotatably engaged by a key. There is provided a key groove inner surface of the movable sheave and a space in a groove that forms a grease flow path between the key and the key groove of the movable sheave, and the grease stored in the key groove is used for the movable sheave. A pulley mounting portion structure of a belt-type continuously variable transmission configured to flow from one end of the keyway to the other end through the grease flow path with sliding. 2. The belt-type continuously variable transmission according to claim 1, wherein the grease flow path is formed between a bottom surface portion of the inner surface of the key groove and the key. Part structure. 3. A pulley mounting portion structure for a belt-type continuously variable transmission according to claim 1, wherein said movable sheave is slidably operated by a driving force of a speed change driving mechanism.