JPH08178002A - Belt type continuously variable transmission - Google Patents

Abstract

PURPOSE: To conduct the speed change operation of a belt type continuously variable transmission at a speed faster than the normal operating speed by conducting the speed change operation of the belt type continuously variable transmission via the operating force of an operation lever, and directly operating a cam type operation mechanism preferentially to an assist mechanism with the operation lever. CONSTITUTION: This belt type continuously variable transmission is provided with an assist mechanism A operating a cam type operation mechanism 15 changing the split width interval of a split pulley 13 based on the detection information of an operation lever 21 by an operating direction detecting means As. The cam type operation mechanism 15 is constituted of an assist operation system having a shift fork 15C sliding a shift member 15B via the action of the assist mechanism A and a manual operation system having a cam member 15A directly sliding the shift member 15B via the action of the operation lever 21 preferentially to the assist mechanism A. The point of application (a) of the shift fork 15C to the shift member 15B is set near the pressing point of application (b) of a transmission belt 14 to the split pulley 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operating direction detecting means for detecting an operating direction of an operating lever, and a cam type operation for changing a split width interval of a split pulley based on detection information from the operating direction detecting means. The present invention relates to a belt-type continuously variable transmission including an assist mechanism including an actuator that operates the mechanism.

[0002]

2. Description of the Related Art A belt type continuously variable transmission is provided with a biasing means for maintaining a transmission belt in the belt type continuously variable transmission in a tensioned state. The operation load when operating the belt-type continuously variable transmission is considerably large. Therefore, in the belt type continuously variable transmission as described above, the operation direction detecting means for detecting the operation direction of the operation lever in accordance with the lever operation when performing the gear shifting operation of the belt type continuously variable transmission, and the detection thereof. While being continued, by providing an assist mechanism composed of an actuator that operates the cam type operating mechanism to change the split width interval of the split pulley in the belt type continuously variable transmission, the operating direction detecting means provides the operating lever. There is a belt type continuously variable transmission that can perform a gear shift operation with an operating force that only detects the operating direction.

Conventionally, a cam type operating mechanism in the belt type continuously variable transmission as described above is disclosed in, for example, Japanese Patent Laid-Open No. 6-201.
As disclosed in Japanese Patent Application Laid-Open No. 007 or Japanese Patent Application Laid-Open No. 6-201039, it is configured as one system of an assist operation system operated by an assist mechanism.

[0004]

However, when the cam type operating mechanism is constructed as one system of the assist operating system as described above, the cam type operating mechanism is always operated by the operation of the actuator. It is impossible to operate the cam type operation mechanism with the operation lever at a speed faster than the operation speed of the actuator of the above, and the belt type continuously variable speed is faster than the normal constant speed shift operation by the operation of the actuator. There has been a problem that the gear shift operation of the device cannot be performed as necessary. Also, if an actuator failure occurs,
Unless the actuator is repaired or replaced, the belt type continuously variable transmission cannot be operated for gear shifting.

An object of the present invention is to enable a gear shifting operation of a belt type continuously variable transmission with an operating force that is usually sufficient to detect the operating direction of an operating lever by an operating direction detecting means, but if necessary, It is intended to enable a direct gear shift operation of a belt type continuously variable transmission by an operation lever.

[0006]

In order to achieve the above object, according to the present invention, an operating direction detecting means for detecting an operating direction of an operating lever, and a split pulley of the split pulley based on detection information from the operating direction detecting means. In a belt type continuously variable transmission equipped with an assist mechanism including an actuator for operating a cam type operation mechanism for changing a split width interval, the cam type operation mechanism is provided in the cam type operation mechanism by operating the assist mechanism. An assist operation system including a shift fork for slidingly operating the shift member for changing the split width interval of the split pulley, and a cam for directly sliding the shift member by operating the operation lever in preference to the assist mechanism. The manual operation system is composed of two members, and the action point of the shift fork with respect to the shift member is defined by the split pulley. It was set in the vicinity of the pressing action point of the transmission belt against.

[0007]

According to the present invention, as the operation lever is operated,
The operating direction of the operating lever is detected by the operating direction detecting means, and the shift fork (assist operating system) of the cam type operating mechanism is operated by the operation of the actuator based on the detected information.
Is operated, the cam member (manual operation system) of the cam type operation mechanism is directly operated by the operation lever. At this time, if the operating speed of the operating lever is made to match the operating speed of the actuator, the shift fork of the cam type operating mechanism will operate the shift member in preference to the cam member, and the split pulley is driven by the power from the actuator. You can now change the split width interval. That is, the shift operation of the belt-type continuously variable transmission can be performed with an operation force that only detects the operation direction of the operation lever by the operation direction detection means. On the other hand, if the operating speed of the operating lever is faster than the operating speed of the actuator, the cam member of the cam type operating mechanism will operate the shift member in preference to the shift fork, and the operating force of the operating lever will directly divide the shift member. You can change the split width of the pulley. That is, the direct operation of the cam type operation mechanism by the operation lever enables the speed change operation of the belt type continuously variable transmission faster than the normal operation speed by the actuator. Further, even if a failure of the actuator occurs, the shift operation of the belt type continuously variable transmission can be performed by directly operating the cam type operating mechanism by the operating lever.

By the way, in the belt type continuously variable transmission, one of the pulley bodies constituting the split pulley is rotatably supported on its supporting shaft. Further, at the contact point between the split pulley and the transmission belt, the tension of the transmission belt acts on the split pulley, and this tension pushes the contact side of the split pulley with the transmission belt to the widening side. Become so. Therefore,
The movable pulley body of the split pulley is slidably operated by the pressing action of the transmission belt at the pressing action point of the transmission belt with respect to the split pulley, which is a contact point between the split pulley and the transmission belt. As a result, the wear between the support shaft and the movable pulley body becomes severe and rattling easily occurs, which causes a problem that a smooth sliding operation of the movable pulley body is difficult to be performed early. Therefore, in the present invention, the action point of the shift fork with respect to the shift member is set in the vicinity of the pressure action point of the transmission belt with respect to the split pulley, so that the push action point side of the movable pulley body in the split pulley is interposed via the shift member. The shift fork receives it. As a result, the movable pulley body is slid in a state of being inclined by the pressing action of the transmission belt at the pressing action point,
It is possible to suppress the inconvenience that the wear between the support shaft and the movable pulley body becomes severe and rattling easily occurs.

[0009]

Therefore, according to the present invention, normally, the belt-type continuously variable transmission can be operated to change gears with a force sufficient to detect the operation direction of the operation lever by the operation direction detecting means, and the speed change can be performed quickly. When it is necessary to operate, by operating the cam type operating mechanism directly over the assist mechanism with the operating lever, the speed of the belt type continuously variable transmission can be changed faster than the normal operating speed by the actuator. You can now operate. Further, in the event of a failure of the actuator, as a first-aid measure, it becomes possible to directly perform a gear shift operation of the belt type continuously variable transmission by the operation lever. Moreover, a smooth sliding operation of the movable pulley body in the split pulley can be obtained for a long period of time.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a combine traveling system will be described below with reference to the drawings.

FIG. 1 shows a combine traveling system. This traveling system is configured to transmit power from the engine 1 to the left and right crawler traveling devices 5 via a belt tension type clutch mechanism 2, a belt type continuously variable transmission 3, and a mission case 4. Has been done. Inside the mission case 4, a hydraulically operated forward clutch 6 that expresses a forward traveling state of the crawler type traveling device 5, a hydraulically operated backward clutch 7 that shows a reverse traveling state of the crawler type traveling device 5, Auxiliary transmission 8 configured to switch the traveling speed of the crawler type traveling device 5 to three stages of high, middle and low, and left and right hydraulically operated side clutches 9 that independently discontinue transmission to the left and right crawler type traveling devices 5, respectively. ,
Also, the left and right hydraulically operated brake mechanisms 1 that independently apply the braking action to the left and right crawler type traveling devices 5, respectively.
0, etc. are deployed.

As shown in FIG. 2, the belt type continuously variable transmission 3 includes an input shaft 11 to which power from the engine 1 is input,
The output shaft 12 that outputs the power from the engine 1 to the transmission case 4, the split pulleys 13 mounted on the input shaft 11 and the output shaft 12, and the transmission belt 14 wound around the split pulleys 13. , And so on. The split pulley 13 mounted on the input shaft 11 functions as a drive pulley 3A in the belt type continuously variable transmission 3. The split pulley 13 mounted on the output shaft 12 functions as a driven pulley 3B in the belt type continuously variable transmission 3. Each of the split pulleys 13 has a fixed pulley body 13A that is integrally and rotatably fixed to each of the input shaft 11 and the output shaft 12, and
The input shaft 11 and the output shaft 12 are integrally rotatable with each other, and the axis P1 of each of the input shaft 11 and the output shaft 12 is provided.
The movable pulley body 13B is slidably fitted in the P2 direction. The input shaft 11 includes a movable pulley body 13 of a split pulley 13 that functions as a drive pulley 3A.
A cam type operation mechanism 15 for slidingly operating B in the direction of the axis P1 is attached. A biasing means 16 for biasing the movable pulley body 13B of the split pulley 13 functioning as the driven pulley 3B toward the fixed pulley body 13A along the axis P2 is attached to the output shaft 12. That is, the cam type operation mechanism 15 and the biasing means 16 maintain the transmission belt 14 in the belt type continuously variable transmission 3 in a tensioned state, and the operation of the cam type operation mechanism 15 divides the drive pulley 3A and the driven pulley 3B. Changing the width interval in a contradictory manner, drive pulley 3
The winding ratio of the transmission belt 14 with respect to each of A and the driven pulley 3B can be changed.

By the way, the urging means 16 is the driven pulley 3
The coil spring 16A that constantly presses the movable pulley body 13B of B to the fixed pulley body 13A side, and the output shaft 12 and the movable pulley body 13B of the driven pulley 3B are integrally and rotatably linked together, and the movable pulley body is in that rotating state. Cam mechanism 16 for pressing the body 13B toward the fixed pulley body 13A
It is composed of B. The cam mechanism 16B is integrally formed on the movable pulley body 13B and a pressing cam body 16a which is spline-fitted to the output shaft 12 so as to be able to rotate integrally, and which has a pressing inclined surface for pressing the movable pulley body 13B. And a pressed cam body 16b formed with a pressed inclined surface that comes into surface contact with the pressing inclined surface, and the pressing inclined surface and the pressed inclined surface make surface contact with the rotation of the output shaft 12. , The axis P of the pressing cam body 16a
When the pressed cam body 16b receives a pressing force around 2, the output shaft 12 and the movable pulley body 13B are integrally rotated, and the pressed cam body 16b generated between the pressed inclined surface and the pressed inclined surface. The movable pulley body 13B is urged toward the fixed pulley body 13A by the component force that pushes in the direction of the axis P2.

As shown in FIGS. 2 to 4, the cam type operation mechanism 15 includes a cam member 15A as a manual operation system which is pivotally supported relative to the input shaft 11 and is non-slidingly supported. Relatively rotatable with respect to the movable pulley body 13B of the drive pulley 3A,
In addition, the input shaft 11 is configured by a shift member 15B pivotally supported so as to be integrally slidable in the direction of the axis P1 of the input shaft 11, and the like. The cam member 15A is formed with a V-shaped guide cam surface 15a for climbing guide that is inclined toward the shift member 15B. The shift member 15B includes a cam member 15
A V-shaped guided cam surface 15b guided by the guide cam surface 15a in accordance with the turning operation of A is formed, and
A pair of guided pins 15c slidably guided in a pair of guide grooves 17a formed in the transmission case 17 are provided in a protruding manner.
The guided member 15c is slidably guided by the guide groove 17a so that the shift member 15B is prevented from rotating. One end of the cam member 15A is the transmission case 1
7, and a boss member 18 is integrally rotatably connected to the protruding one end.
An operation plate 19 is integrally rotatably fixed to the boss member 18, and a friction plate 20 for holding the attitude of the operation plate 19 is interposed between the operation plate 19 and the transmission case 17. There is. An operation lever 21 for rotating the operation plate 19 is pivotally supported on the boss member 18 via one of a pair of operation pieces 19a and 19b provided on the operation plate 19. When the operation lever 21 is located at the neutral position N, the cam member 15 in the cam type operation mechanism 15
The guide cam surface 15a of A and the guided cam surface 15b of the shift member 15B are in close contact with each other, and the split width interval between the fixed pulley body 13A and the movable pulley body 13B in the drive pulley 3A is set to be the maximum separation state. There is. That is, when the operation lever 21 is located at the neutral position N, the winding ratio of the transmission belt 14 with respect to each of the drive pulley 3A and the driven pulley 3B in the belt type continuously variable transmission 3 appears to be the lowest speed state. Is set to. By rotating the operation lever 21 from the neutral position N in the forward direction F and the reverse direction R around the axis P1, the guide cam surface 15a of the cam member 15A in the cam type operation mechanism 15 causes the shift member 15B to move. The guided cam surface 15b is climbed up and guided, and the winding ratio of the transmission belt 14 to each of the drive pulley 3A and the driven pulley 3B in the belt type continuously variable transmission 3 is changed to the speed increasing side.

As shown in FIGS. 4 and 5, the operating lever 2
Reference numeral 1 denotes an operation lever 21 that is interlocked with a switching valve 22 that switches the flow state of hydraulic oil to the forward clutch 6 and the reverse clutch 7 via a push-pull wire 23.
Positive direction (forward direction) F around the axis P1 from the neutral position N
The switching valve 22 is connected to the forward clutch 6 in conjunction with the turning operation to
Is switched to the state in which hydraulic oil is supplied and the forward clutch 6 is switched to the on state, whereby the forward traveling state of the crawler type traveling device 5 is revealed. Further, the switching valve 22 is switched to a state in which hydraulic oil is supplied to the reverse clutch 7 in conjunction with a turning operation from the neutral position N of the operation lever 21 in the reverse direction (reverse direction) R around the axis P1. At the same time, the reverse clutch 7 is switched to the engaged state so that the reverse running state of the crawler type traveling device 5 is revealed. At the neutral position N of the operation lever 21, the switching valve 22 is switched to a state in which hydraulic oil is discharged from each of the forward clutch 6 and the reverse clutch 7, and the forward clutch 6 and the reverse clutch 7 are switched to the disengaged state, thereby the crawler type. The power from the engine 1 to the traveling device 5 is cut off.
Incidentally, reference numeral 24 shown in FIG. 5 indicates the operation lever 21 and the switching valve 2.
The switching valve 22 of the operating lever 21
This is a flexible mechanism that allows an operation of more than the operation amount for switching the operating state of.

With the above construction, by operating the operating lever 21 from the neutral position N in the forward direction F about the axis P1, the forward traveling state of the crawler type traveling device 5 can be brought out and the operating lever can be displayed. The forward speed of the crawler type traveling device 5 can be changed steplessly by changing the turning operation amount of 21 in the forward direction F. Further, by operating the operation lever 21 from the neutral position N in the reverse direction R around the shaft center P1, the reverse traveling state of the crawler type traveling device 5 can be revealed, and
By changing the amount of rotation of the operating lever 21 in the reverse direction R, the reverse speed of the crawler type traveling device 5 can be changed steplessly.

As shown in FIG. 6, the operation path of the operation lever 21 is defined by the guide plate 25. The guide plate 25 includes a forward shift path 25a that allows a forward shift operation of the crawler type traveling device 5 by an operation around the axis P1 of the operating lever 21, and a crawler type traveling device 5 by an operation around the axis P1 of the operating lever 21. A reverse speed change path 25b that allows a reverse speed change operation, and a change of the operation path between the forward speed change path 25a of the operation lever 21 and the reverse speed change path 25b by the operation of the operation lever 21 in the direction of the axis P1. The neutral path 25c is formed to communicate. As shown in FIGS. 2 and 4, the operation lever 21 has an operation portion 21.
a is pivotally supported by the base end portion 21b so as to be swingable in the direction of the axis P1. The operation portion 21a is urged by a spring (not shown) toward the side that stands up along the extended line of the base end portion 21b. In this standing state, the operating portion 21a is located on the forward speed change path 25a, and can be operated around the axis P1 in the forward speed change path 25a. Further, in the neutral path 25c, the operation portion 21a is positioned on the reverse speed change path 25b against the bias of the spring 21c, so that the operation around the axis P1 in the reverse speed change path 25b can be performed.

As described above, the belt type continuously variable transmission 3
Is provided with urging means 16 for urging the movable pulley body 13B of the driven pulley 3B toward the fixed pulley body 13A. Therefore, the operation load applied to the operation lever 21 when operating the belt type continuously variable transmission 3 to the speed increasing side is considerably heavy. On the other hand, the operation load applied to the operation lever 21 when the belt type continuously variable transmission 3 is operated to the deceleration side is considerably light. Therefore, the belt type continuously variable transmission 3
Is provided with an assist mechanism A that reduces an operation load applied to the operation lever 21 when the belt type continuously variable transmission 3 is operated to the speed increasing side.

As shown in FIGS. 2, 4 and 7, the assist mechanism A uses the operation direction detecting means As for detecting the operation direction of the operation lever 21 and the detection information from the operation direction detecting means As. The shift fork 15C as an assist operation system in the cam type operation mechanism 15 is configured by a motor Am that is an example of an actuator that operates via the pinion gear 26 and the sector gear 27. In the shift fork 15C, each of the action portions 15d is operated by the operation lever 2 with respect to the guided pin 15c of the shift member 15B.
It is pivotally supported by the transmission case 17 so as to abut from the first side, and the action portion 15d presses the guided pin 15c of the shift member 15B by the operation of the motor Am.
The shift member 15B is connected to the movable pulley body 13 of the drive pulley 3A.
It is configured to be slid on the fixed pulley body 13A side together with B. The operation direction detecting means As is the operation plate 19
The first limit switch s1 installed on the one operation piece 19a, the second limit switch s2 installed on the other operation piece 19b of the operation plate 19, and the second limit switch s2 installed on the guide plate 25 near the middle portion of the neutral path 25c. The third limit switch s3 and a control device C that controls the operation of the motor Am based on the output signals from these switches s1, s2, and s3. The motor Am is equipped with a worm gear type reduction mechanism wg. The first limit switch s1 outputs an ON signal to the control device C when the operation lever 21 is rotated in the forward direction F. The second limit switch s2 is the operation lever 2
The ON signal is output to the control device C in accordance with the turning operation of 1 in the reverse direction R. The third limit switch s3 outputs an ON signal to the control device C each time the operating lever 21 passes. The control device C is
The motor Am is rotated only when the ON signal from the first limit switch s1 or the second limit switch s2 is input, and the first limit is input each time the ON signal from the third limit switch s3 is input. Switch s1 or second limit switch s
It is configured to switch the rotation direction of the motor Am based on the ON signal from 2. By the way, operating lever 2
In No. 1, free swinging around the axis P1 with respect to the boss member 18 is suppressed by the bias of the spring 21c provided at the base end portion 21b thereof. The spring 21c is locked by a locking tool 19c provided on the operation plate 19 so as to rotate integrally with the operation plate 19.

That is, the control device C receives the ON signal from the third limit switch s3 0 times or even times and then inputs the ON signal from the first limit switch s1 into the motor Am. Of the shift fork 15C to drive the pulley 3A.
By swinging to the side, the shift member 15B of the cam type operation mechanism 15 resists the bias of the biasing means 16 and the movable pulley body 13B of the drive pulley 3A together with the fixed pulley body 1.
It is designed to slide on the 3A side. When the ON signal from the second limit switch s2 is input, the cam Am is rotated by rotating the motor Am in the reverse direction to swing the shift fork 15C in the direction opposite to the drive pulley 3A side. The shift member 15B of the manual operation mechanism 15 is driven by the biasing means 16 to drive the drive pulley 3
Along with the movable pulley body 13B of A, it is slid on the side away from the fixed pulley body 13A. on the other hand,
In a state where the ON signal from the first limit switch s1 is input after the ON signal from the third limit switch s3 is input an odd number of times, the motor Am is rotated in the reverse direction to drive the shift fork 15C. By oscillating in the opposite direction to the pulley 3A side, the shift member 15B of the cam type operating mechanism 15 is separated from the fixed pulley body 13A together with the movable pulley body 13B of the drive pulley 3A by the urging of the urging means 16. It is designed to be slid on. Also, O from the second limit switch s2
When the N signal is input, the motor Am is rotated in the forward rotation direction to swing the shift fork 15C toward the drive pulley 3A, whereby the shift member 15B of the cam type operation mechanism 15 is attached. The movable pulley body 13B of the drive pulley 3A is slid toward the fixed pulley body 13A side against the bias of the biasing means 16. When the shift member 15B of the cam type operation mechanism 15 is slid to the side of the drive pulley 3A away from the fixed pulley body 13A by the urging of the urging means 16, the fixed pulley of the shift member 15B. Body 13A
The cam type operation mechanism 15
The cam member 15A is rotationally operated around the axis P1.

With the above construction, the operating speed of the operating lever 21 is made to match the operating speed of the motor Am, so that the shift fork 15C as the assist operating system of the cam type operating mechanism 15 is replaced by the cam member 15 as the manual operating system.
The shift member 15B is operated in preference to A,
The split width interval of the split pulley 13 can be changed by the power from the motor Am. That is, the first limit switch s1 of the operation direction detecting means As is operated by the operation lever 21.
Alternatively, the second limit switch s2 is turned on, and the control lever C is operated by the control device C of the operation direction detecting means As.
The belt-type continuously variable transmission 3 can be operated to change gears with an operation force for detecting the operation direction.

On the other hand, by making the operating speed of the operating lever 21 faster than the operating speed of the operation of the motor Am, the cam member as a manual operating system of the cam type operating mechanism 15 in the speed-up operating direction of the operating lever 21. 15A is
The shift member 15B is operated with priority over the shift fork 15C as the assist operation system, and the split width interval of the split pulley 13 on the drive pulley 3A side can be directly changed by the operating force of the operation lever 21. Like Further, in the deceleration operation direction of the operation lever 21, the operation lever 21 operates the cam member 15A as a manual operation system.
Can be operated prior to the sliding operation of the shift member 15B by the urging of the urging means 16, and the urging of the urging means 16 widens the split width interval of the split pulley 13 on the drive pulley 3A side. The operational load generated when the shift member 15B is changed to is reduced by the amount that the cam member 15A is rotated in accordance with the sliding operation of the shift member 15B. That is,
In the speed increasing direction of the operating lever 21, the motor Am
The speed-increasing operation of the belt type continuously variable transmission 3 faster than the normal operation speed can be performed according to the operation speed of the operation lever 21. Further, in the deceleration operation direction of the operation lever 21, the deceleration operation of the belt type continuously variable transmission 3 faster than the normal operation speed by the motor Am by the amount of the operation load for the urging of the urging means 16 is reduced. You can do it. Further, in the deceleration operation direction of the operation lever 21, the operation lever 21 can be operated to the neutral position N prior to the sliding operation of the shift member 15B by the urging of the urging means 16, and by this operation, the crawler is operated. The traveling device 5 can be stopped suddenly.

As shown in FIGS. 2 and 7, the shift member 15B of the cam type operating mechanism 15 includes the respective guided pins 15c.
Is arranged so as to project along the direction in which the drive pulley 3A and the driven pulley 3B are arranged, and the shift fork 15C has respective action portions 15d along the direction in which the drive pulley 3A and the driven pulley 3B are arranged. They are arranged side by side. That is, the shift member 1 of the shift fork 15C
One of a pair of action points a with respect to 5B is set in the vicinity of a pressure action point b of the transmission belt 14 with respect to the movable pulley body 13B of the drive pulley 3A. Thereby, the movable pulley body 13B in the drive pulley 3A
The pressing action point b side can be received by the shift fork 15C via the shift member 15B, and the movable pulley body 13B is slid by the pressing action of the transmission belt 14 at the pressing action point b in a tilted state. In order to obtain a smooth sliding operation of the movable pulley body 13B for a long period of time, it is possible to suppress the inconvenience that the wear between the input shaft 11 and the movable pulley body 13B becomes severe and rattling easily occurs. There is.

[Other Embodiments] Other embodiments of the present invention will be listed below. In the above embodiment, the present invention is applied to the traveling system of the combine, but the present invention is not limited thereto, and may be applied to the traveling systems of other work vehicles such as harvesters, Further, the present invention may be applied to a transmission system for a work device such as a handle cylinder that is operated to change gears. Incidentally, when the present invention is applied to a power transmission system for a work device, the guide cam surface 15a of the cam member 15A and the guided cam surface 15b of the shift member 15B are used.
It is not necessary to form each of them in a V shape, but it may be formed in a one-sided inclined shape. The belt type continuously variable transmission 3 includes a drive pulley 3A.
Only one of the driven pulley 3B and the driven pulley 3B is the split pulley 13.
It may be configured by. The belt type continuously variable transmission 3 may be configured such that the driving pulley 3A side is provided with the biasing means 16 and the driven pulley 3B side is provided with an operation system such as a cam type operation mechanism 15. In this case, the operating force of the operating lever 21 can be directly changed to the side where the split width interval of the split pulley 13 on the driven pulley 3B side is narrowed, and the belt type stepless speed faster than the normal operating speed by the motor Am. Transmission 3
The deceleration operation can be performed according to the operation speed of the operation lever 21. In the above embodiment, when the operation speed of the operation lever 21 is set higher than the operation speed by the operation of the motor Am, the operation position shift fork (assist operation system) corresponding to the operation position of the cam member (manual operation system) 15A. ) 15C
It is necessary to turn on the first limit switch s1 or the second limit switch s2 of the operation direction detecting means As by the operation lever 21 until the position is reached. Therefore, a first potentiometer for detecting the operation position of the operation lever 21, a second potentiometer for detecting the operation position of the shift fork 15C, and a comparison means for comparing the respective operation positions are provided and detected by the first potentiometer. Shift fork 1 corresponding to the operating position of the operating lever 21
If the motor Am is operated until the operation position of 5C is detected by the second potentiometer, the first limit switch s is operated by the operation lever 21 until the shift fork 15C is located at the operation position of the cam member 15A.
It is possible to eliminate the need to turn on the first or second limit switch s2. Further, in this case, since the operation position and the operation direction of the operation lever 21 can be discriminated by the first potentiometer, the first potentiometer is used as the first limit switch s1, the second limit switch s2, and the third limit switch s2. Instead of the limit switch s3, it can be made to function as the operation direction detecting means As.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a traveling system of a combine.

FIG. 2 is a vertical sectional rear view of the belt type continuously variable transmission.

FIG. 3 is a plan view of a cam member and a shift member.

FIG. 4 is a left side view of a belt type continuously variable transmission.

FIG. 5 is a linkage diagram showing the linkage between the operation lever and the forward clutch and the reverse clutch.

FIG. 6 is a plan view showing the structure of a guide plate.

FIG. 7 is a right side view of a belt type continuously variable transmission showing a disposition direction of a shift fork and a shift member.

[Explanation of symbols]

 13 Split pulley 14 Transmission belt 15 Cam type operating mechanism 15A Cam member 15B Shift member 15C Shift fork 21 Operating lever A Assist mechanism Am Actuator As Operating direction detecting means a Operating point b Pressing operating point

Claims (1)

[Claims] 1. A split pulley (1) based on operating direction detecting means (As) for detecting the operating direction of an operating lever (21) and detection information from the operating direction detecting means (As).
3) A belt type continuously variable transmission equipped with an assist mechanism (A) including an actuator (Am) for operating a cam type operation mechanism (15) for changing the split width interval of the cam type operation mechanism ( A shift fork (15) for slidingly operating a shift member (15B) for changing the split width interval of the split pulley (13) in the cam type operation mechanism (15) by operating the assist mechanism (A).
C) and the operation lever (2
1) The shift member (15B) is configured into two systems of a manual operation system including a cam member (15A) that directly slides the assist mechanism (A) in preference to the assist mechanism (A), and the shift is performed. The action point (a) of the shift fork (15C) on the member (15B) is set to the split pulley (1).
3) A belt type continuously variable transmission which is set in the vicinity of the pressing action point (b) of the transmission belt (14) against 3).