JPH04236842A - Belt type continuously variable transmission - Google Patents

Abstract

PURPOSE:To perform reliable and easy operation of a clutch and to prevent dislocation and corotation of a belt by interlocking a clutch pedal with a shift cam or a belt guide. CONSTITUTION:A belt type continuously variable transmission 14 performs engaging and disengaging operation by means of a tension clutch pulley 36 around which a transmission belt 17 is run and the belt 17 is operated by a clutch pedal 12. In the belt type continuously variable transmission, after a shift cam is transferred to the low speed side, the shift cam is interlocked with the clutch pedal 12 so that the tension clutch pulley 36 is engaged. A belt guide 33 movable to the transmission belt 17 is provided. The belt guide 33 and the clutch pedal 12 are interlocked with each other so that when the tension clutch pulley 36 is disengaged by means of the clutch belt 12 in the case of the shift cam being located on the low speed side, the belt guide 33 is moved to the vicinity of the transmission belt 17.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a belt-type continuously variable transmission device applied to mobile agricultural machinery such as agricultural tractors, and in particular, the present invention relates to a belt-type continuously variable transmission device that is applied to mobile agricultural machinery such as agricultural tractors, and in particular, a belt-type continuously variable transmission device that is adapted to interlock a clutch pedal and a speed change cam or a belt guide. This invention relates to a continuously variable transmission.

0002

[Prior Art] As a belt-type continuously variable transmission device for mobile agricultural machinery, a drive pulley and a driven pulley whose contact surface diameters with the belt are each variable controlled by variable speed cams that are installed on the outer surface of the pulley and interlock with each other. It has been proposed that a transmission belt is wound between the belt and the pulley, and the belt is turned on and off by a tension clutch pulley operated by a clutch pedal. In this conventional belt-type continuously variable transmission, the clutch pedal is operated independently, and even when the shift cam is shifting to the high speed side or the low speed side, that is,
``Enter'' and ``off'' operations are possible throughout the entire gear range. It is also known that a fixed belt guide is provided for the power transmission belt.

0003

[Problems to be Solved by the Invention] As described above, when the clutch pedal is designed to be able to be operated to "engage" and "disengage" over the entire gear shift range, the outer surfaces of both the driving pulley and the driven pulley are mutually connected to each other. A variable speed cam linked to the belt is installed to control the diameter of the contact surface of both pulleys with the belt.
In a so-called double cam type continuously variable transmission, when the clutch is "disengaged" on the high-speed side of the transmission belt, even if an attempt is made to shift the gear using the gear shift lever, the drive pulley is not rotating, so the gear cannot be shifted. Furthermore, it is difficult to "disengage" the clutch throughout the entire speed range. Furthermore, since the diameter of the contact surface with the belt of both the drive pulley and the driven pulley is controlled to vary, a fixed belt guide cannot guide the belt sufficiently, causing various problems such as the belt rotating together. There was a problem. The present invention has been made to solve the above problems.

0004

[Means for Solving the Problems] In order to achieve the above objects, the present invention provides: (1) provided on the outer surface of the pulley;
A tension clutch pulley in which a transmission belt is wound between a driving pulley and a driven pulley, in which the diameter of the pulley's contact surface with the belt is varied and controlled by mutually interlocking variable speed cams, and the belt is operated by a clutch pedal. in"
In a belt-type continuously variable transmission device that operates to engage and disengage, the shift cam and clutch pedal are connected so that the tension clutch pulley becomes disengaged after the shift cam is shifted to the low speed side. (2) A movable belt guide is provided for the transmission belt, and the belt guide and the clutch pedal are configured to interlock with each other.
Each belt guide is characterized by an interlocking configuration in which the belt guide moves close to the transmission belt when the tension clutch pulley is operated to "off" by the clutch pedal when the speed change cam is on the low speed side.

[0005]

[Function] With the above configuration, the speed change cam and clutch pedal are linked so that the tension clutch pulley is turned off after the speed change cam is shifted to the low speed side, so the clutch "disengagement" action is light and and be carried out reliably. ■ After the shift cam is shifted to the low speed side, the clutch is disengaged, so the shift operation to the high speed side can be performed from that state, so there is no effect on the shift lever due to the clutch being "engaged" or "disengaged". . ■ Since the start of running is performed from the low speed side, there is no sudden start and there is no need to shift to the low speed side using the gear shift lever. ■
When the movable belt guide and the clutch pedal are operated to "disengage" the clutch by using the clutch pedal when the speed change cam is on the low speed side, the belt guide is interlocked to move close to the transmission belt, so that the belt guide disengages the clutch.
The clutch performs the necessary operation to "disengage", and the clutch "disengage" operation is performed reliably. Further, it is sufficient to simply provide a movable belt guide on the drive pulley side, and the belts are prevented from rotating together when the clutch is in the "disengaged" state.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described in detail with reference to the accompanying drawings. The riding-type rice transplanter (mobile agricultural machine) to which the present invention is applied shown in FIG. A seedling planting section 7 is attached to the rear part via an elevating link 6 consisting of a parallel link, a hydraulic cylinder, etc. In the traveling vehicle body 5, there is a driver seat 8, a steering handle 9, a main gear shift lever 10, a continuously variable gear lever 11, and when switching the main gear lever 10, and when a tension clutch pulley of a continuously variable transmission device (to be described later) is turned on. , a clutch pedal 12, a transmission case 13, etc., which are used when performing a "cut" operation, and the engine 4 and the transmission case 13 are provided with a belt-type continuously variable transmission 14.

As shown in FIGS. 1 to 4, the belt type continuously variable transmission 14 has two pulleys, one of which is movable in the axial direction, and the diameter of the contact surface with the transmission belt is controlled to vary. A transmission belt 17 as a tension belt is wound between an engine pulley 15 (driving pulley) and a mission pulley 16 (driven pulley). The engine pulley 15 has a movable pulley 15a on the engine 4 side, and the mission pulley 16 has a movable pulley 16a on the side away from the mission case 13 (outside), each movable in the axial direction and rotatable in the circumferential direction. Cam surfaces 18 and 1 are provided on the outer surfaces of both movable pulleys 15a and 16a, respectively.
Fixed cams 20 and 21 are provided which form a cam surface 9 and have two rollers that roll into contact with the cam surfaces 18 and 19. The fixed cam 20 is rotated by a rotation prevention arm 22 supported on the side of the engine 4, and the fixed cam 21 is rotated by a rotation prevention arm 25 supported by a front axle case 23 of the front wheel 1 via a bolt 24. It is stopped and supported. In addition, both moving pulleys 15a
, 16a connects an interlocking rod 28 in the form of a link to connecting members 26 and 27 provided respectively, and both movable pulleys 15
a and 16a are interlocked and rotated relative to each other.

A link rod 31 connects the connecting member 27 of the movable pulley 16a and a long hole 30 formed in the rotating plate 12a, which rotates around the shaft 29 when the clutch pedal 12 is depressed. are doing. Further, a rotating plate 12a,
A belt guide 33 rotatably provided around a shaft 32 near the engine pulley 15 is connected to a link rod 34.
It is connected by A fixed belt guide 35 is provided on the outer periphery of the pulley 16, and a pair of fixed belt guides 35a, 35a are provided near the pulley 15 and outside the transmission belt 17. Switch the tension of the transmission belt 17, turn the clutch on,
Tension clutch pulley 3 to switch to “off” state
6 is pivotally supported by a tight arm 37, and the tight arm 37 is pivotally supported by a shaft 38 and is biased upward by a tension spring 39 provided above the tension clutch pulley 36. The clutch is energized to be in the "engaged" state.

The clutch pedal 12 is pivotally supported on the aircraft body by a shaft 32, and is given a return behavior by a return spring 40, so that when depressed, the clutch of the transmission device (not shown) in the transmission case 13 is turned to the "disengaged" state. At the same time, the connecting rod 41 extending forward from near the shaft 32 is connected to the connecting portion 37 extending on the opposite side from the shaft 38 of the tight arm 37.
a and when the clutch pedal 12 is depressed, the tight arm 37 is rotated counterclockwise about the shaft 38 through the connecting rod 41 and the connecting portion 37a against the elastic force of the tension spring 39. , tension clutch pulley 36,
The transmission belt 17 is moved to release the tension, and the clutch of the belt-type continuously variable transmission 14 is placed in the "off" state. Further, since the link rods 31 and 34 are connected to the rotary plate 12a of the clutch pedal 12, when the clutch pedal 12 is depressed, the clutch in the transmission case 13 is turned to the "disengaged" state as described above. , by rotating the linking member 27 and rotating the linking member 26 via the linking rod 28, the fixed cam 19,
20 (i.e., variable speed cam), the movable pulleys 15a, 16
After shifting a to the low speed side, tension clutch pulley 3
The speed change cam and clutch pedal 12 are interlocked so that 6 is in the "off" position, and at the same time, the belt guide 33 approaches the transmission belt 17 (engine pulley 15).

As shown in FIGS. 5 and 6, a trochanter 4 made of a ball bearing is mounted on the side surface of the tight arm 37.
2 is provided, and also coaxial with the tight arm 37 (shaft 38
) is also provided with a trochanter 44 made of a ball bearing. Like the tight arm 37, this support plate 43 is also urged upward by a tension spring 45. A neutral arm 46 and a shift arm 47 are fixed to the continuously variable transmission lever 11 at a predetermined interval, and are supported by a shaft 48 to sequentially move from a neutral position to a low speed position and from a low speed position to a high speed position. It is rotatably supported so that it can move in sequence. The neutral arm 46 and the shift arm 47 each have a cam surface, and are adapted to come into sliding contact with the rotors 42 and 44, respectively. Also,
The cam surfaces of the neutral arm 46 and the shift arm 47 are provided with a neutral groove, a neutral release groove, a shift groove, etc.
By the rotation of the trochanters 42 and 44, they come into sliding contact and engage with the trochanters 42 and 44, respectively.

[0011] Then, the neutral arm 46 and the moving pulley 1
The movable pulley 15a is connected to the connecting member 26 by a connecting rod 49 (cam operation member) in the form of a link. rotates, and in conjunction with the rotation of the movable pulley 15a, the movable pulley 16a is relatively rotated via the interlocking rod 28, and the engine pulley 15 is rotated by the cam surfaces 18, 19 and the fixed cams 20, 21.
By relatively changing the belt contact surface diameter of the transmission pulley 16 and the transmission pulley 16, the transmission rotation ratio by the transmission belt 17 is changed steplessly. The connecting rod 49 is not limited to being connected between the neutral arm 46 and the connecting member 26 of the movable pulley 15a, but may be connected between the shifting arm 47 and the connecting member 26 of the movable pulley 15a. It is something. Although not shown, the movement range of the continuously variable speed lever 11 includes:
Shift grooves are provided that engage the neutral arm 46 and the shift arm 47 in correspondence with their respective shift positions. Reference numeral 50 is an adjustment bolt that adjusts the neutral position of the continuously variable speed lever 11.

In the belt type continuously variable transmission device having such a configuration, when changing the traveling speed of the traveling vehicle body 5, the continuously variable transmission lever 11 is moved to the neutral position, that is, the neutral arm 46
The neutral groove of the transmission arm 47 and the trochanters 42 and 44 are shifted to a position where they slide into contact with each other, and the clutch pedal 12 is depressed to release the transmission clutch (not shown) in the transmission case 13 and Belt type continuously variable transmission 1
4 clutches are both in the "disengaged" state as shown in Figure 3,
First, the main shift lever 10 is switched, then the continuously variable shift lever 11 is switched, and the depression of the clutch pedal 12 is released, so that the clutch is "on" and the vehicle body 5 runs at a predetermined speed. When changing the traveling speed of the traveling vehicle body 5 while it is traveling, use the clutch pedal 12.
Step down to stop the vehicle, and then press the continuously variable transmission lever 1.
1 and release the clutch pedal 12, the desired traveling speed can be obtained.

When the clutch pedal 12 is depressed as described above, the link rod 31 rotates the link member 27, the link rod 28 rotates the link member 26, and the fixed cams 19 and 20 rotate the movable pulley 15a. , 16a
After shifting to the low speed side, the tension clutch pulley 36 becomes "off" as described above. At the same time, the belt guide 33 is connected to the transmission belt 17 by the link rod 34.
The fixed belt guides 35, 35 move so that they approach each other.
a and 35a, the transmission belt 17 is uniformly lifted off the engine pulley 15 belt to ensure clutch disengagement, and also prevents the transmission belt 17 from coming off the pulleys 15 and 16, and also prevents the transmission belt 17 from coming off the pulleys 15 and 15. prevent co-rotation. Further, during a normal speed change operation using the continuously variable speed lever 11, the link rod 31 is moved by the elongated hole 30 so that the clutch pedal 12 side is not affected. and,
The tension clutch pulley 36 is the movable pulley 15a, 1
6a always shifts to the low speed side and enters the "cut" state after that, the fixed belt guide 35 may be used on the pulley 16 side, and the purpose can be sufficiently achieved by making the belt guide 33 movable.

[0014]

[Effects of the Invention] As explained above, according to the belt type continuously variable transmission of the present invention, the following effects can be achieved. ■ After shifting the speed change cam to the low speed side, the speed change cam and clutch pedal are interlocked so that the tension clutch pulley is "disengaged", so the clutch "disengage" operation can be performed lightly and reliably. ■ After the shift cam is shifted to the low speed side, the clutch is "disengaged", so the shift operation to the high speed side is performed from that state.
There is no longer any effect on the gear shift lever due to clutch ``engagement'' or ``disengagement''. - Since the start of running is performed from the low speed side, there is no sudden start, and there is no need to use the gear shift lever to shift to the low speed side, making it possible to perform speedy and effortless gear shifting operations. ■ When the movable belt guide and the clutch pedal are operated to "disengage" the clutch with the clutch pedal when the speed change cam is on the low speed side, the belt guide moves in the vicinity of the transmission belt, so the belt guide disengages the clutch. The clutch performs the necessary operation to "disengage", and the clutch "disengage" operation is performed reliably. Further, it is sufficient to simply provide a movable belt guide on the drive pulley side, which simplifies the configuration and reliably prevents the belt from coming off and rotating together when the clutch is in the "disengaged" state.

[Brief explanation of the drawing]

FIG. 1 is a side view of an embodiment of the invention.

FIG. 2 is a side view of essential parts of the present invention.

FIG. 3 is an explanatory diagram of the operation of the present invention.

FIG. 4 is a plan view of an embodiment of the invention.

FIG. 5 is a plan view of essential parts of the present invention.

FIG. 6 is a rear view of essential parts of the present invention.

FIG. 7 is a side view of a riding-type rice transplanter to which the present invention is applied.

[Explanation of symbols]

10 Main shift lever 11 Sub-shift lever 12 Clutch pedal 12a Rotating plate 13 Mission case 14 Belt-type continuously variable transmission 15 Engine pulley (driving pulley) 16 Mission pulley (driven pulley) 15a, 16a Moving pulley 17 Transmission belt 18, 19 Cam Surfaces 20, 21 Fixed cams 26, 27 Connecting member 28 Interlocking rods 29, 32, 38 Shafts 31, 34 Link rod 33 Belt guides 35, 35a Fixed belt guide 36 Tension clutch pulley 37 Tight arm 37a Connecting portion 41 Connecting rod

Claims (2)

[Claims] Claim 1: A transmission belt is wound between a driving pulley and a driven pulley in which the diameter of the contact surface of the pulley with the belt is varied and controlled by variable speed cams provided on the outer surface of the pulley and interlocking with each other. The belt is then "engaged" by a tension clutch pulley operated by a clutch pedal.
In a belt-type continuously variable transmission device that is operated to "disengage," the shift cam and clutch pedal are interlocked so that after the shift cam is shifted to the low speed side, the tension clutch pulley is "disengaged." A belt-type continuously variable transmission device characterized by having the following configuration. 2. A movable belt guide is provided for the transmission belt, and when the belt guide and the clutch pedal are operated to "disengage" the tension clutch pulley with the clutch pedal when the speed change cam is on the low speed side,
2. The belt type continuously variable transmission according to claim 1, wherein the belt guide is configured to move in the vicinity of the transmission belt.