JPH032038Y2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Field of Industrial Application The present invention relates to a continuously variable transmission device for a work vehicle such as a combine harvester, and more particularly to a structure for making the device compact.

(b) Prior Art Conventionally, a continuously variable transmission device in a work vehicle such as a combine harvester, as devised in Japanese Utility Model Application Publication No. 58-20758, uses a movable side pulley and a fixed side pulley installed above a transmission case. An endless belt is wound between a driving side split pulley consisting of a single piece and a driven side split pulley installed in the case,
The driving side split pulley is actuated by a hydraulic actuator, and by changing the width of the movable side pulley piece and the fixed side pulley piece of the split pulley, the endless belt is appropriately pressed and moved in the circumferential direction. By changing the transmission ratio between the pulleys, the speed of the combine is controlled steplessly.

(c) Problems to be solved by the invention However, the conventional continuously variable transmission described above is operated by a hydraulic actuator that is installed largely protruding from the circumference of the drive-side split pulley. There is a risk of increasing the size and creating wasted space inside the aircraft.

Furthermore, like the actuator, the device that detects the moving position of the movable pulley piece that makes up the drive-side split pulley is installed away from the split pulley, which makes maintenance difficult, such as troublesome repairs in the event of a breakdown. There is a risk of sexual deterioration.

(d) Means for solving the problem The purpose of the present invention is to solve the above-mentioned problems. For example, as shown in Figs. For example, an actuator 35 for operating the split pulley 26 is installed coaxially with the shaft 25 between the case 23 and the movable pulley piece 33 of the split pulley 26 on the drive shaft 25). Further, a position detection device 36 for detecting the movable position of the actuator 35 and a rotation stop device 37 for preventing the rotation of the actuator 35 are installed, respectively, so that the actuator 35, the position detection device 36, and the rotation stop device 37 are arranged in the same manner as described above. It is characterized by being configured to fit within the circumference of the split pulley 26 when viewed from the side.

(E) Effect Based on the above configuration, when the actuator 35 is actuated by the operator's operation, the actuator 35 slides the movable pulley piece 33 of the driving side or driven side split pulley (for example, the driving side split pulley 26) as appropriate. Then, the endless belt b is pressed between the pulley piece 33 and the fixed pulley piece 32, and thereby the belt b is appropriately moved in the circumferential direction of the driving side split pulley 26 to be moved between it and the driven side split pulley 21. The transmission ratio by the belt is changed, and the continuously variable transmission 20 is controlled to change the speed continuously. When the actuator 35 is activated, its rotation is prevented by the rotation stopper 37, and the position detection device is activated to detect the position of the movable pulley piece 33, thereby controlling the drive side split pulley 26. It can be controlled as appropriate in response to operator operations.

(F) Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings.

As shown in FIG. 4, the combine C has a body 2 supported by a crawler 1 driven by a sprocket S, and an engine 3 is mounted on one side of the body 2 at the rear. At the same time, a driver's seat 5 is arranged in the front, and a grain tank 6 is installed between them, and an automatic threshing machine is installed on the other side of the fuselage 2. Further, a pre-processing section 7 is arranged in the front of the machine body 2 so as to be movable up and down, and a mission case 9 is mounted in the lower part of the machine body 2 at the rear thereof.

As shown in FIG. 1, the transmission case 9 includes a traveling system transmission section 10, a side clutch,
A main transmission 13 consisting of a brake device 11 and a traveling system drive unit 12 is housed therein, and an axle 15 protrudes from the lower part of the transmission case 9 and has the sprocket S fixed to its tip.
Further, a submission case 17 housing a pretreatment system drive unit 16 is integrally fixed to the upper part of the mission case 9.
A shaft 19 is rotatably supported at one end and protrudes from the shaft 19, and a driven side split pulley 21 constituting a continuously variable transmission 20 is fixed at one end to the fuselage. It is installed and supported by a bracket 22. On the other hand, above the integral transmission cases 9 and 17, a counter case 23 having an oil filler port 23a formed in the upper part is disposed, and a shaft 25 is supported through the counter case 23. At the same time, a hydraulic pump P is bolted to the outside thereof. The shaft 25 has a driving side split pulley 26 supported at one end thereof, and its tip is supported by a bracket 27 fixed to the machine body. An endless belt b is wound around the continuously variable transmission 20.
It consists of A transmission pulley 28 is fixed to the other end of the shaft 25, and a gear 29 is fixed to the inside of the counter case 23.
Further, an endless belt d is wound around the transmission pulley 28, and the rotation of the engine 3 is transmitted to the pulley 28 via the belt d. Further, the hydraulic pump P has a drive shaft 30 rotatably supported inside the counter case 23, and a gear 31 is fixed to one end of the shaft 30, and the gear 31 is connected to the gear 29. are engaged.

Further, the driving side split pulley 26 is connected to the fixed sheave 3
2 and a movable sheave 33, the movable sheave 33 has a boss portion 33a connected to the shaft 25.
It is slidably fitted into the boss portion 32a of the fixed sheave 32 which is fitted and fixed to the end of the fixed sheave 32, and is urged in a direction away from the fixed sheave 32 by a spring 34. Furthermore, the movable sheave 33 in the drive side shaft 25 and the counter case 23
A hydraulic actuator 35 for appropriately operating the sheave 33 is installed between the actuator 35, a position detection device 36 for detecting the position of the movable sheave 33 is installed above the actuator 35, and a position detection device 36 for detecting the position of the movable sheave 33 is installed below the actuator 35. A rotation stopper 37 is installed to prevent the actuator 35 from rotating. Further, the driven side split pulley 21 is composed of a movable sheave 39 and a fixed sheave 40, and the movable sheave 39
The boss portion 39a is fixed to the boss portion 4 of the sheave 40.
0a, and is urged toward the fixed sheave 40 by a spring 41 to press the endless belt b against the sheave 40.

On the other hand, the position detection device 36 is
As shown in FIG.
It is fixed to the outer circumference with a bolt 49, and one end of a link 745 is fixed to the tip of the link 43 with a bolt 50.
It is supported by The potentiometer 42 is connected to an inverted U-shaped plate 52 bolted to the upper side of the cylinder portion 51 of the actuator 35.
is installed on the upper surface 52a of the casing 53 with its shaft 42a protruding downward;
Further, an arm 55 having a U-shaped tip is screwed to the tip of the shaft 42a. Further, below the potentiometer 42, a link 46 is rotatably installed at an upper end 56a of a pin 56 erected on the lower surface 52b of the plate 52, and furthermore, a link 46 is rotatably installed at one end of the link 46. 57 is erected, and the pin 57 has its tip connected to the U-shaped portion 55 of the arm 55.
It is held in a. Further, the other end of the link 45 is pivotally supported at the other end of the link 46 by a bolt 59, and the link 46 is configured to rotate around a pin 56 as the link 43 moves in the direction of arrow A. has been done.

Further, as shown in FIGS. 1 and 3, the rotation stopper 37 includes a rib 51a formed on the lower side of the cylinder portion 51 of the actuator 35, and a cross-sectional member having one end fixed below the outer periphery of the piston 47. When the piston 47 moves to operate the drive-side split pulley 26, the stop device 37 is configured by combining a square-shaped rate member 60, so that the rail member 60 slides along the rib 51a. This prevents the piston 47 from rotating around the shaft 25.

Since this embodiment has the above configuration,
The transmission pulley 28 to which the rotation of the engine 3 is transmitted by the endless belt d rotates the drive side split pulley 26 together with the drive side shaft 25 to transmit the rotation of the continuously variable transmission 2.
Drive 0. Furthermore, the gear 29 rotates together with the shaft 25 and drives the hydraulic pump P via the gear 31 and the shaft 30.

The drive-side split pulley 26, which rotates together with the drive-side shaft 25, causes the movable sheave 33 to slide toward the fixed sheave 32 due to the movement of the piston 47 caused by the actuation of the actuator 35, and furthermore, the sheave 33 appropriately moves the endless belt b. The belt b is moved toward the outer periphery of the split pulley 26 by pressure contact. At this time, in the driven side split pulley 20, the belt b is moved inward of the split pulley to change the transmission ratio of the continuously variable transmission device 20, and the speed of the device 20 is controlled to increase. Conversely, when the operation of the actuator 35 is weakened, the movable sheave 33 moves in the direction of opening the split pulley 26 due to the biasing force of the spring 34, and as a result, the movable sheave 33 discharges oil from the actuator 35. Move quickly without being affected by back pressure. Therefore, the belt b is moved inward on the driving side split pulley 26 and moved toward the outer circumference on the driven side split pulley 21 side, so that the continuously variable transmission 20 is quickly controlled to decelerate.

Then, during the speed increase and deceleration control of the continuously variable transmission 20 described above, the piston 4 of the actuator 35
7, the rail portion 60 installed below the rib 5
By sliding along 1a, the shaft 25
The movable sheave 3 of the split pulley 26 can be moved by being prevented from rotating around the
3 and move the link 43 of the position detection device 36 in the direction of arrow A. As a result, the link 4
3, the link 45 moves and rotates the link 46 around the pin 56. Then, the pin 57 is rotated in the same direction, thereby rotating the arm 55 and rotating the shaft 42a of the potentiometer 42. Therefore,
The position detection means 36 operates the potentiometer 42 in accordance with the amount of movement of the movable sheave 33 to detect the position of the sheave 33, thereby detecting the position of the continuously variable transmission 20.
The speed can be controlled as appropriate.

Then, the driven side shaft 19, which is transmitted with the appropriately changed rotation by the continuously variable transmission 20, transmits the rotation to the pretreatment transmission section 16 and the traveling system transmission section 10, and the pretreatment section is switched by the operator's switching operation. 7 and the travel system as appropriate.

(g) Effects of the invention As explained above, according to the invention, the drive side or driven side shaft (for example, the drive side shaft 2
Since the actuator 35 for operating the split pulley 26 is installed coaxially with the shaft 25 between the case 23 and the movable pulley piece 33 of the split pulley 26 in 5), the movable pulley piece 3 of the split pulley 26
3 can be rationally arranged to be pressed from between the case 23 and the pulley piece 33, and thereby the continuously variable transmission 20 can be made compact. Furthermore, a position detection device 36 for detecting the movable position of the actuator 35 and the actuator 3 are provided.
Since a rotation stop device 37 is installed to prevent the rotation of the actuator 35, the actuator 35 can slide in the axial direction of the drive shaft 25 without rotating, thereby smoothly operating the position detection device 36. The position of the movable pulley piece 33 can be detected accurately, and the continuously variable transmission 20 can therefore be operated accurately in response to the operator's operations. Furthermore, since these actuator 35, position detection device 36, and rotation stop device 37 are configured to fit within the circumference of the split pulley 26 in side view, these actuator 35, position detection device 36, and rotation stop device 37 are In addition to being compact, it can be protected by the movable sheave 33. Therefore, the actuator 35 etc. can be protected from straw debris etc. during reaping work by the operating vehicle C, and it can also be protected during assembly and painting. Open the split pulley 26 and move the movable sheave 3.
3 to the case 23 side, it is possible to protect the actuator 35 and the like from getting paint on it, and therefore masking can be omitted and the work can be simplified.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing a continuously variable transmission according to the present invention, Fig. 2a is a side view showing its position detection device, Fig. 2b is a plan view thereof, and Fig. 3 is a rotation stopper. FIG. 1 is a sectional view taken along the - line in FIG. 1, and FIG. 4 is a side view showing the entire combine harvester. 17, 23... Case (submission case, counter case), 19... Driven side shaft,
20... Continuously variable transmission, 21... Drive side split pulley, 25... Drive side shaft, 26... Drive side split pulley, 32... Fixed side pulley piece (fixed sheave),
33...Movable pulley piece (movable sheave), 35...
... Actuator, 36 ... Position detection device, 37
...Rotation stop device, b... Endless belt, C... Work vehicle (combine harvester).

Claims (1)

[Scope of Claim for Utility Model Registration] A driving side split pulley and a driven side split pulley each consisting of a movable side pulley piece and a fixed side pulley piece are installed on a driving side shaft and a driven side shaft supported protruding from a case, and these split pulleys In a work vehicle equipped with a continuously variable transmission configured by winding an endless belt between them, an actuator for operating the split pulley is disposed between the case and the movable pulley piece of the split pulley in the driving or driven shaft. A position detection device that detects the movable position of the actuator and a rotation stop device that prevents rotation of the actuator are installed coaxially with the shaft, and these actuator, position detection device, and rotation stop device are installed, respectively. A continuously variable transmission device for a work vehicle configured to fit within the circumference of the split pulley in a side view.