JPH11278296A - Travel device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the controllability and traveling performance of a traveling vehicle which uses a crawler as its travel means, such as a combine, by making it possible to change its traveling direction or to freely select its turning radius during turning. SOLUTION: A differential type travel device 19 which drives a pair of crawlers, such as a combine, comprises a travel speed shift device which has a traveling HST 20 of a continuously variable hydrostatic main transmission means and an auxiliary transmission 25 provided at the rear stage of the traveling HST 20, etc., and which provides outputs to the pair of right and left crawlers, and a traveling direction steering device which comprises a turning HST 70 of a hydrostatic continuously variable transmission means, the turning HST 70 receiving the input of power from a position beyond the output shaft of the traveling HST 20 and in front of the input shaft of the auxiliary transmission means 25 and selectively transmitting the output of the turning HST 70 to one of the crawlers of the combine to cause the traveling vehicle such as the combine to turn and travel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling apparatus used for a traveling vehicle using a crawler as traveling means.

[0002]

2. Description of the Related Art As a traveling vehicle using a crawler as a traveling means, a prior art will be described by taking an agricultural combine as an example. The combine increases the ground contact area of the crawler traveling vehicle so that it can travel freely even in a soft field such as a paddy field, thereby enabling agricultural work such as harvesting.

[0003] The combine has an engine as a power source and uses the power generated by the engine for running, cutting, threshing, etc. of the combine. The crawler shifts the power of the engine by a traveling transmission and transmits and drives the power. I do. The traveling transmission includes a hydrostatic stepless transmission, a gear train mechanical transmission, a reverse gear, a clutch, and a brake.

When the combine is traveling straight, a pair of right and left crawlers are driven at a constant speed. When the combine is turned left and right, the left and right crawlers are driven with a difference in speed so that the high-speed crawlers are moved outward and the low-speed crawlers are moved outward. It is configured to be able to turn with the crawler on the side, stop side or retreat side inside.

[0005] Changing the traveling direction and turning of the combine
In each case, one crawler is classified into three types: a slow turn in which the speed of the other crawler is reduced while the front crawler is traveling forward, a braking turn in which the other crawler is stopped by braking, and a sharp turn in which the other crawler reversely runs in reverse.

[0006] The straight running and turning of the combine is performed by an operator on the control platform of the combine operating various control levers to change the power to be transmitted, brake or reverse to move the crawler forward, stop and retreat. The combine is driven forward or backward or turned.

[0007]

SUMMARY OF THE INVENTION The harvesting and threshing of cereal culms to be planted in a field using a combine have been progressing in labor saving and efficiency in harvesting cereals. In addition, the use of a hydrostatic transmission (HST), which combines a variable displacement axial plunger pump and a fixed displacement axial plunger motor capable of continuously changing the speed in the traveling transmission of the combine, makes it possible to travel the combine. The speed can be changed by operating one HST lever, and the driving operation has become considerably easier.

Further, one power steering lever (hereinafter referred to as "power steering lever") is provided on the control console of the combine, and the power harvesting device is vertically moved up and down by tilting the power steering lever back and forth, and the power steering lever is tilted left and right. As a result, the combine is configured so that the traveling direction can be changed and turned left and right, and the maneuvering operation is further facilitated for an operator who is not skilled in the operation of the combine.

However, the speed of the crawler providing the speed difference is given by switching and transmitting each clutch and / or brake inside the traveling transmission. There are only three types of turning and fixed speed reverse traveling sharp turning, and therefore, only three turning radii of gentle turning, braking turning and sharp turning. Therefore, there is a problem in the driving operation that the operator still requires a high level of skill in the operation of changing the traveling direction of the combine.

Further, since it is necessary to provide a gear mechanism for causing the crawler to perform the three types of turning, there is a limit in reducing the size of the transmission, and the power of the traveling HST is reduced by the auxiliary transmission. After that, the power is transmitted to the turning gear mechanism, so that there is a limit to downsizing of the traveling HST.

An object of the present invention is to improve the operability and traveling performance of a traveling vehicle using a crawler such as a combine as a traveling means, in which a traveling direction can be changed and a turning radius at the time of turning can be freely selected. And

[0012]

The above object of the present invention is attained by the following constitution. In other words, there is provided a stepless main transmission means capable of continuously inputting power from a power source and continuously changing the rotation speed from the power source, and a subtransmission means provided at a subsequent stage of the main transmission means. A traveling speed transmission device selectively connected to a pair of crawlers, and inputting power of the main transmission device from a position after an output shaft of a main transmission device and before an auxiliary transmission device input shaft of the traveling speed transmission device. And a continuously variable speed traveling direction steering device that is operably connected to a crawler on one side of a pair of left and right crawlers.

In order to facilitate understanding of the present invention, a traveling apparatus (transmission) 19 for driving a pair of crawlers 3L, 3R such as a combine 1 will be described with reference to an example of a traveling apparatus shown in the following drawings. HST20 for traveling, which is a hydrostatic main transmission means capable of stepwise shifting, and HST2 for traveling
0, a traveling speed transmission device that outputs to the pair of left and right crawlers 3L or 3R, and a traveling direction steering device that includes a turning HST 70 that is a hydrostatic stepless transmission device. HST7 for turning
0 is input power from a position before the output shaft of the traveling HST 20 and before the input shaft of the subtransmission means 25, and the turning HST 70
Is selectively transmitted to one of the crawlers 3L or 3R of the combine 1 to make the traveling vehicle such as the combine 1 turn.

Thus, for example, the operator who has boarded the combine 1 can set an arbitrary turning radius for any of the gentle turning, the braking turning and the sharp turning by setting the turning speed lever 53, and can turn the power steering lever 60. The turning steering can be performed only by performing the tilting operation in the desired direction, and the steering operation of the combine 1 becomes extremely easy. In addition, since the turning HST 70 is capable of normal and reverse rotation by itself and has a braking effect in the neutral position,
Conventionally required left and right brake devices, spin clutch devices, reversing gear trains, and the like are not required, and the structure of the transmission can be simplified and downsized.

The turning HST 70 is a traveling HST.
Since the input is performed from a position after the output shaft 20 and before the input shaft of the subtransmission 25 (or in the case of a combine, it may be input from the output shaft of the reaper 6), the subtransmission 25 HST20 for traveling without being affected
Can be turned at a speed proportional to the speed of the vehicle. Further, the torque increased by the auxiliary transmission 25 is applied to the turning HST.
70, the torque capacity of the turning HST 70 can be reduced.
0 can be reduced in size.

[0016]

Embodiments of the present invention will be described with reference to the drawings. One embodiment of the present invention is shown in FIGS. FIG. 1 is a left side view of a combine 1 which is an example of a traveling vehicle according to an embodiment of the present invention, FIG. 2 is a front view of the combine 1, and FIG. FIG. 4 is a partial sectional view of a clutch actuator and a clutch of the traveling transmission, and FIG. 5 is a hydraulic circuit diagram for controlling a clutch of the traveling transmission.

As shown in FIGS. 1 and 2, a traveling section 4 having a pair of left and right traveling crawlers 3L and 3R that travels on the soil surface is disposed below the body frame 2 of the combine 1 and is provided on the body frame 2. A reaper 6 is provided on the front end side. The cutting device 6 includes a weeding tool 8 for weeding the planted grain culm,
A raising case 9 for raising the planted grain culm, a cutting blade 11 for cutting the planted grain culm, a stock carrier 12 and a supply carrier 7 for nipping and transporting the harvested grain culm backward. It is configured.

The reaper 6 includes a reaper supporting frame 1 that moves up and down about a fulcrum above the body frame 2.
3, the operator boarding the combine 1 tilts the power steering lever 60 of the control table 50 back and forth, so that the operator moves up and down together with the reaper support frame 13.

Above the body frame 2, a threshing device 15 having a feed chain 14 for taking over and transporting the grain stalks conveyed from the supply / conveyance device 7 of the reaper 6;
A grain tank 16 for temporarily storing the grains selected by threshing by the threshing device 15 is placed, a vertical auger 16a is erected at the rear of the grain tank 16, and a horizontal auger 16b is connected to the vertical auger 16a. The grain in the Glen tank 16 is discharged to the outside of the combine 1.

That is, in the combine 1, the operator operates the main shift HST lever 51 and the auxiliary shift lever 52 (FIG. 2) on the control console 50, and the power of the engine (not shown) of the main transmission of the transmission 19 shown in FIG. The speed is changed via the hydrostatic transmission HST20 and the gear transmission means of the auxiliary transmission 25, and transmitted to the right and left crawlers 3L and 3R to travel at an arbitrary speed.

In the combine 1, the operator operates the turning speed shift lever 53 on the control console 50 to select gentle turning, braking at an arbitrary speed, or sharp turning at an arbitrary speed, and tilts the power steering lever 60 right and left. By operating, the vehicle can turn right and left at an arbitrary radius. That is, when the power steering lever 60 is tilted in the direction in which the combine 1 is to be turned, the clutch in the transmission 19 shown in FIG. 3 is activated, and the continuously variable transmission HST7 for turning at a preselected speed.
0 rotation power to crawler left 3L or crawler right 3R
Therefore, a speed difference is given to the left and right crawlers 3L and 3R to change the traveling direction.

The main parts of the transmission 19 shown in FIG. 3 include a main transmission hydrostatic transmission HST20, an auxiliary transmission 25, a side clutch 36L,
36R, second side clutches 44L, 44R, traveling shaft 3
9L, 39R, crawler driven sprocket wheel 40
L, 40R, etc., and is provided with an input pulley 19a of driving force from the engine, a reaper drive pulley 27a for transmitting power to the reaper 6, and the like.

As shown in FIG. 3, the transmission 19 includes a turning hydrostatic transmission (turning HST) 70 driven by the output of the traveling HST 20, and the output of the turning HST 70 is the side clutch 34 and the second HST. By switching the side clutch 44, the power is selectively transmitted to the crawler left 3L or the crawler right 3R.

The mechanical rotation driving force transmitted from the engine to the input pulley 19a is converted into hydraulic pressure by the variable displacement hydraulic pump 21 of the traveling HST 20 and the discharge amount is changed. Is converted.
By controlling the swash plate of the variable displacement hydraulic pump 21, the oil flow can be changed from 0% to ± 100% in a stepless manner. In response to this oil pressure, the rotation speed of the hydraulic motor 23 is steplessly increased from 0% to + 100%. It can change to minus 100%.

The output shaft 24 of the hydraulic motor 23 is provided with a hydraulic motor output extension shaft 26, which is fixedly provided with a hydraulic motor output pinion 26a. The gear 31 is driven. The sub-transmission second gear 30 and the sub-transmission third gear 29 are formed integrally with the first gear 31, and are loosely fitted to the sub-transmission shaft 27 so as to be slidable in the axial direction and relatively non-rotatable. The auxiliary transmission first gear 31, the auxiliary transmission second gear 30, and the auxiliary transmission third gear 29 are
Is operated, the shaft is shifted in the axial direction through a sub-shift shifter (not shown), and the first gear 31 and the first counter gear 31 ', the second gear 30 and the second counter gear 30', Three gear 29 and third counter gear 2
9 'is selected, and the countershaft 28 is sub-shifted to any one of high speed, medium speed, and low speed. The sub-transmission shaft 27 rotates together with the first gear 31 to transmit power to the reaper drive pulley 27a.

The first counter gear 31 'directly meshes with the gear 32a fixed to the second counter shaft 32 (FIG. 3 is an exploded view, so that the gear 31' and the gear 32a do not seem to mesh). By transmitting the rotation of the counter shaft 28 at the sub-speed, the second counter shaft 32
The pinion 32b fixed to the side clutch shaft 33
(The pinion 32b and the center gear 34 do not appear to be engaged with each other since FIG. 3 is an exploded view).

The center gear 34 has annular clutch teeth 34L, 34R protruding in the form of protrusions and recesses in the axial direction on both left and right inner peripheral sides of the gear disk. The side clutch left 36L provided with the side clutch tooth profile left 35L protruding in the unevenness in the axial direction opposite to the direction clutch tooth profile 34L is loosely fitted in the axially slidable manner, and is normally urged by the coil spring 33L. The axial clutch tooth profile 34L and the side clutch tooth profile left 35L mesh non-rotatably to transmit power to the side clutch left 36L, and the transmitted power meshes with the pinion 37L fixed to the side clutch left 36L. 38
And drives the crawler left 3L via the running shaft left 39L and the crawler sprocket left 40L.

The side clutch shaft 33 is provided with a side clutch right 36R engraved with a side clutch tooth right 35R protruding annularly and unevenly in the axial direction opposite to the clutch tooth profile 34R so as to be freely slidable in the axial direction. The axial clutch tooth 34R and the side clutch right 35R mesh with each other so that they cannot rotate relative to each other to transmit power to the right side clutch 36R, and the transmitted power is transmitted to the right side clutch right. Pinion 3 fixed to 36R
It is transmitted to the first traveling gear 38R that meshes with 7R, and drives the right crawler 3R via the right traveling shaft 39R and the right crawler sprocket 40R.

The transmission 19 has two clutch shifters 41L and 41R.
L and 41R each have approximately two L-shapes with two arms, and support the corners of the L-shape with a rotating shaft, and rotate by the operation of a clutch actuator 103 which will be described in detail later. The above-mentioned side clutches 36L, 36R and second side clutches 44L, 44R described below are connected and released, respectively.

The outer periphery of the left side clutch 36L forms a revolving gear 42L. The revolving gear 42L is integral with a second side clutch left 44L that is axially slidably and rotatably loosely fitted to the second side clutch shaft 43. Clutch pinion 43
L engages.

The outer periphery of the right side clutch 36R forms a revolving gear 42R, and the revolving gear 42R is integrated with a second side clutch right 44R that is axially slidably and rotatably loosely fitted on the second side clutch shaft 43. Clutch pinion 4
Mesh with 3R. The outer periphery of the left side clutch 36L forms a revolving gear 42L. The revolving gear 42L is axially slidable and freely rotatably loosely fitted to the second side clutch shaft 43 in a clutch pinion 43L integral with the second side clutch left 44L. Mesh with.

The outer periphery of the right side clutch 36R forms a revolving gear 42R, and the revolving gear 42R is integrated with a second side clutch right 44R that is axially slidably and rotatably loosely fitted on the second side clutch shaft 43. Clutch pinion 4
Mesh with 3R.

Two clutch plates 45L and 45R are fixed to the second side clutch shaft 43, and the second side clutch left 44L and the clutch plate 45L, and the second side clutch right 44R and the clutch plate 45R are respectively in the axial direction. The clutch shifter 41L and 41R actuate the clutch to connect or disconnect. A second side clutch input gear 43a is provided at the shaft end of the second side clutch shaft 43.
Is fixed.

The turning HST 70 is the traveling HST 2 described above.
HST drive pinion 26 for turning which is fixed to hydraulic motor output extension shaft 26 of traveling HST 20 with the same configuration as driving HST 20
b through the HST drive gear 72a for turning, and the HS
Driving the T input shaft 72, the transmitted mechanical rotation driving force is:
The hydraulic pressure is converted into a hydraulic pressure by the variable displacement hydraulic pump 71 of the HST 70, and the hydraulic pressure is converted again into a mechanical rotational force by the hydraulic motor 73.

By controlling the variable displacement hydraulic pump 71, the oil flow can be steplessly increased from 0% to ± 100%.
In response to this oil pressure, the rotation speed of the hydraulic motor 73 can be changed from 0% to ± 100% steplessly, and the variable displacement hydraulic pump 7
When the oil flow rate is zero, the hydraulic motor 73 acts as a brake.

An output pinion 74 a is fixed to an output shaft 74 of the hydraulic motor 73, and an intermediate gear 75 fixed to an intermediate shaft 75.
a, and an intermediate pinion 75 integrated with the intermediate gear 75a.
b drives the second side clutch shaft 43 by meshing with the second side clutch input gear 43a fixed to the shaft end of the second side clutch shaft 43.

That is, the transmission 19 transmits the rotational power of the engine to the traveling HST 20 and the auxiliary transmission 25.
When the side clutches 36L, 36R are connected, the traveling shafts 39L, 39R, and thus the crawler driving sprockets 40L, 40R are driven at a constant speed, and the crawler left 3L and the crawler right 3R travel at a constant speed. Then, the combine 1 is caused to travel straight.

FIG. 4 is a partially cutaway sectional view of the vicinity of the clutch actuator 103, the side clutch 36 and the second side clutch 44, and FIG. 5 is a hydraulic circuit diagram for clutch control. FIGS. 3, 4 and 5 show the side clutch 36 when the combine 1 is turned to the left.
4 shows the connection and disengagement relations of the second side clutch 44.

That is, the clutch actuator 103 shown in FIG. 4 has two cylinders 81L and 81R,
Pistons 82L and 82R are slidably and loosely fitted to the cylinders 81L and 81R and pistons 82L and 82R, respectively.
And seal rings 83L and 83R for sealing between the piston 82 and the piston 82 by urging springs 84L and 84R.
L and 82R are urged upward in FIG. Cylinder 8
When hydraulic oil is pressed into 1L or 81R, the piston 8
2L or 82R is a biasing spring 84L or 84R
4, the push rod 85L or 85R is pressed downward, and the push rod 85L or 85R is rotated by pressing the clutch shifter 41L or 41R.

In the hydraulic circuit 100 shown in FIG. 5, the hydraulic oil in the drain tank 105 is pumped up by the hydraulic oil pump 101 and pressurized, and the pressurized hydraulic oil is controlled by the electromagnetic solenoid valve 102 to selectively operate the actuator. In this configuration, the liquid is supplied to the actuator 103, the actuator 103 is operated, and the power steering lever 60 is hydraulically levitated.

By tilting the power steering lever 60 to the left or right, the electrical contact 61L or 61R is turned on, the electromagnetic solenoid valve 102 is driven to move the valve spool right or left, and the cylinder 81L or the cylinder 81L of the actuator 103 is moved. 81R is pressurized and piston 82L
Or operate 82R.

The operation of the transmission (differential traveling device) 19 having the above configuration will be described below. First, when the combine 1 travels straight, the power steering lever 60 is set at a neutral position (an upright position) where the power steering lever 60 is not tilted to the left or right. Since the electrical contacts 61L and 61R are both OFF, the electromagnetic solenoid valve 102 does not operate and is in the neutral position, and the hydraulic oil of the hydraulic oil pump 101 only returns to the drain tank 105 from the open center of the electromagnetic solenoid valve 102, No liquid is sent to the clutch actuator 103. Piston 8 of clutch actuator 103
2L and 82R are urged upward by an urging spring (Fig. 4).
Therefore, the clutch shifters 41L and 41R do not operate, while the coil springs 33L and 33R are urged (FIG. 3) to connect the side clutches 36L and 36R.
The second side clutches 44L, 44R are released.

In this case, the power generated by the engine is H
ST20, auxiliary transmission 25, side clutch 36L, 36
R, running shaft 39L, 39R, crawler sprocket 40
L and 40R, transmitted at a constant speed,
Since L and 3R are driven at a constant speed, the combine 1 travels straight (see FIG. 3).

With the power steering lever 60 in the neutral position, the turning HST 70 is driven by the output of the running HST 20 while the combine 1 is traveling straight, but the turning speed lever 53 (see FIG. Even if operated to the position, since the second side clutches 44 and 44R are released, the traveling direction of the combine 1 is not affected, and no power load is applied to the turning HST 70.

When turning the combine 1, first, the turning speed lever 53 of the control console 50 is set to a required turning speed position. The turning speed position can be set steplessly to the braking turning (brake turning) or the gentle turning side, or steplessly to the sharp turning side.

As an example, the operation in the case where the turning speed lever 53 is set to one gentle turning speed position and the combine 1 traveling forward moves slowly to the left will be described. The operator boarding the control platform 50 tilts the power steering lever 60 to the left (FIG. 5 shows the combine 1 from the front,
When the power steering lever 60 is turned left and right, the electrical contact 61L is turned on, the spool of the electromagnetic solenoid valve goes to the right, and the hydraulic pressure of the hydraulic oil pump 101 passes through the electromagnetic solenoid valve 102 to the clutch actuator. Acting on the cylinder left 81L of 103, the piston 82L is pressed, the push rod left 85L is pressed against the spring 84L, and the clutch shifter 41L is rotated. And, by the rotation of the clutch shifter 41L,
The engagement between the axial clutch tooth profile 34L of the center gear 34 and the side clutch tooth profile left 35L is released, the side clutch left 36L (FIG. 3) is released, and the second side clutch shaft 43 is slidable and rotatable in the axial direction. The left side 44L of the second side clutch loosely fitted to the second side clutch shaft 4
3 is connected to the clutch plate 45L fixed to the third clutch plate 3.

At this time, the turning gear 42L on the outer periphery of the left side clutch 36L is a clutch pinion 43L integral with the second side clutch left 44L of the second side clutch shaft 43.
Remains engaged. This clutch pinion 43L
As shown in FIG. 3, the intermediate shaft 74 and the intermediate shaft gear 75
a, intermediate shaft pinion 75b, second side clutch input 4
HS for turning via 3a and clutch plate 45L
The rotational power decelerated to a slow speed in the set forward direction from T70 is transmitted to the second side clutch shaft 43, and the rotational power is transmitted from the side clutch left 36L to the traveling shaft left 39L,
Crawler 3L is slowly rotated through crawler sprocket left 40L.

At this time, as shown in FIG.
0 is output from the hydraulic motor 23 via the turning HST drive pinion 26b and the turning HST input gear 72a.
Input to the ST hydraulic pump 71, the hydraulic pump 71 discharges a flow rate according to the setting of the turning speed setting lever 53, drives the turning HST hydraulic motor 73, and thus shifts slowly to the set forward direction. To transmit the output.

That is, when the vehicle turns slowly to the left, the power generated by the engine is applied to the left 3L of the crawler by the traveling HST2.
0, turning HST70, second side clutch left 44L,
Through the running shaft left 39L and the crawler sprocket left 40L, the transmission is performed at a slow speed in the set forward direction at a slow speed. In this case, for the crawler right 3R,
The power generated by the engine is the main transmission HST20, the auxiliary transmission 2
5, via the right side clutch 36R, the right running shaft 39R, and the right crawler sprocket 40R, so as to be transmitted at the same speed as when traveling straight. Therefore combine 1
Is a slow speed crawler left 3L due to a speed difference between the slow speed crawler left 3L and the same speed crawler right 3R as when traveling straight.
Make a gentle left turn with the inside. When making a right turn, it works in the opposite way to the above.

Since the turning HST 70 can be steplessly adjusted from forward rotation to reverse rotation, the left and right crawlers 3L, 3R
From almost zero to almost twice the forward speed. That is, if the output rotation speed of the turning HST 70 is set to the normal rotation high speed, the left and right crawlers 3
The speed difference between L and 3R is small, and acts so as to make a gentle turning with a large turning radius. If the output rotation speed of the turning HST 70 is reduced to the forward rotation speed, the speed difference between the left and right crawlers 3L and 3R increases, so that the turning operation is performed with a small turning radius. If the output rotation speed of the turning HST 70 is set to zero, the turning HST 70 operates as a brake, and one of the crawlers 3 stops. I do.

If the output rotation speed of the turning HST 70 is set to the reverse rotation low speed, the speed difference between the left and right crawlers 3L and 3R becomes even larger, and the combine 1 acts so as to make a sharp turn with a smaller turning radius than the braking turn. I do. HST7 for turning
If the output rotation speed of 0 is reversed at the same speed as that of the forward side, the left and right crawlers 3L and 3R run in opposite directions at the same speed, so that the combine 1 turns sharply with the smallest turning radius on the spot. Act like so. The braking turn,
In each of the gentle turning mode and the sharp turning mode, the buff steer lever 60 is shown in FIG.
As shown in the figure, this is performed by selecting the angle of inclination.

N is neutral, the clutch is "disengaged" at the position A, the continuously variable speed of gentle turning is performed between the position A and the position B, the braking turning is selected at the position B, and the positions B and C are changed.
The stepless speed change of the sharp turn is performed between the positions, and at the position C, the sharp turn in which the crawler inside the turn direction of the sharp turn reversely rotates at the same rotation speed as the outside.

As described above, in the embodiment of the present invention,
In a traveling vehicle such as a combine 1 having a pair of crawlers 3L and 3R as traveling means, a turning HS serving as traveling direction steering means is provided to a transmission 19 of a traveling speed transmission.
The transmission 19 includes a traveling HST 20 which is a main transmission means capable of steplessly shifting, and a sub-transmission means 25 provided at a subsequent stage of the traveling HST 20.
In addition, a turning HST 70, which is a hydrostatic stepless transmission, is used as the traveling direction steering means, and the hydrostatic stepless transmission HST70 is connected to the auxiliary transmission 25 after the output shaft of the traveling HST 20, which is the main transmission. Power is inputted from a position before the input shaft, and the output of the hydrostatic stepless transmission means 70 is selectively transmitted to one crawler 3L or 3R so that the traveling vehicle such as the combine 1 is turned. It is characterized by the following.

Thus, for example, the operator who has boarded the combine 1 can set an arbitrary turning radius for the gentle turning, the braking turning, and the sharp turning by setting the turning speed lever 53, and can turn the power steering lever 60. The turning steering can be performed only by tilting in the direction to be attempted, and the steering operation of the combine becomes extremely easy.
In addition, since the turning HST 70 is capable of normal and reverse rotation by itself and has a braking effect at the neutral position, the left and right brake devices, spin clutch devices, reverse gear train, etc., which were required in the past, become unnecessary, and the transmission The structure can be simplified and downsized.

The turning HST 70 is a traveling HST.
Since the input is performed from a position after the output shaft 20 and before the input shaft of the subtransmission 25 (or in the case of a combine, it may be input from the output shaft of the reaper 6), the subtransmission 25 HST20 for traveling without being affected
Can be turned at a speed proportional to the speed of the vehicle. Further, the torque increased by the auxiliary transmission 25 is applied to the turning HST.
70, the torque capacity of the turning HST 70 can be reduced.
ST70 can be downsized.

The HST 20 is used as the main transmission.
However, as a main transmission, a continuously variable transmission of another type, for example, a belt-type continuously variable transmission (Belcon)
However, the same effect can be obtained.

FIG. 7 shows a side view of the traveling transmission 19 of the combine 1 (a view taken along the line AA in FIG. 3). The traveling HST 20 and the turning HST 70 of three hydraulic components that generate heat by hydraulic operation. The clutch actuator (push cylinder) 103 and the clutch actuator (push cylinder) 103 are dispersedly arranged on the three surfaces of the traveling transmission 19, as shown in FIGS. The components are cooled by the convection of the respective surrounding air, and the circulating hydraulic oil is also dispersed for each hydraulic component and acts so as to be cooled without being influenced by each other. Therefore, it is possible to prevent the temperature of the hydraulic oil including the hydraulic oil and the entire temperature of the traveling transmission 19 from rising.

[0058]

According to the present invention, there is no influence of the sub-transmission by the sub-transmission means and the torque increased by the sub-transmission means is not input to the turning transmission.
The torque capacity of the turning transmission can be reduced, and the size can be reduced. The torque capacity of the turning transmission can be reduced and downsized, and the rotation ratio of the straight-moving power and the rotation ratio of the turning power can be the same. In addition, since the hydrostatic stepless variable speed traveling steering device is used as the turning transmission, the traveling direction of the traveling vehicle can be changed or the turning radius at the time of turning can be freely selected, so that operability and traveling performance can be improved. it can.

[Brief description of the drawings]

FIG. 1 is a left side view of a combine according to an embodiment of the present invention.

FIG. 2 is a front view of the combine according to the embodiment of the present invention.

FIG. 3 is a partially cut-away expanded sectional view of the transmission of the combine according to the embodiment of the present invention.

FIG. 4 is a partial cross-sectional view of a clutch actuator and a clutch of the transmission of the combine according to the embodiment of the present invention.

FIG. 5 is a hydraulic circuit diagram for clutch control of the transmission of the combine according to the embodiment of the present invention.

FIG. 6 is a diagram illustrating selected angles of respective turning modes using the power steering lever of the combine according to the embodiment of the present invention.

FIG. 7 is a view showing a modification of the embodiment of the present invention, and is a side view of the transmission of the combine taken along line AA of FIG. 3;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Combine 2 Body frame 3 Traveling crawler 4 Running part 6 Cutting device 7 Supplying and conveying device 8 Weeding tool 9 Raising case 11 Cutting blade 12 Stock transfer device 13 Cutting device support frame 14 Feed chain 15 Threshing device 16 Glen tank 19 Transmission 20 H for traveling
ST 21 Variable displacement hydraulic pump 23 Hydraulic motor 24 Hydraulic motor output shaft 25 Sub transmission 26 Hydraulic motor output extension shaft 26a Hydraulic motor output pinion 26b HST drive pinion for turning 27 Sub transmission shaft 27a Mowing device drive pulley 28 Counter shaft 29 Sub transmission Third gear 29 'Third counter gear 30 Secondary speed second gear 30' Second counter gear 31 Secondary speed first gear 31 'First counter gear 32 Second counter shaft 32a Gear 32b Pinion 33 First clutch shaft 33L, 33R Coil spring 34 Center gear 34L, 34R Axial clutch teeth 35L, 35R
Clutch tooth profile 36 Side clutch 36L Side clutch left 36R Side clutch right 37L, 37R
Pinion 38L, 38R First running gear 39L Running shaft left 39R Running shaft right 40L Crawler drive sprocket left 40R Crawler drive sprocket right 41L, 41R Clutch shifter 42L, 42R
Slewing gear 43 Second side clutch shaft 43a Second side clutch input gear 50 Flight control table 51 Main speed H
ST lever 52 Sub speed change lever 53 Turning speed lever 60 Power steering lever 61L, 61R
Electric contacts 70 HST for turning 71 HST variable displacement hydraulic pump for turning 72 HST variable displacement hydraulic pump input shaft for turning 73 HST hydraulic motor for turning 74 HST hydraulic motor output shaft for turning 74a HST hydraulic motor output pinion for turning 75 Intermediate shaft 75a Intermediate shaft gear 75b Intermediate shaft pinion 81L, 81R Clutch actuator cylinder 82L, 82R Clutch actuator piston 83L, 83R Clutch actuator seal ring 84L, 84R Clutch actuator / biasing spring 85L, 85R Clutch actuator push rod 100 Hydraulic circuit 101 Hydraulic oil pump 102 Electromagnetic solenoid valve 103 Clutch actuator 104 Relief valve 105 Drain tank

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[Procedure amendment]

[Submission date] April 14, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0051

[Correction method] Change

[Correction contents]

If the output rotation speed of the turning HST 70 is set to the reverse rotation low speed, the speed difference between the left and right crawlers 3L and 3R becomes even larger, and the combine 1 acts so as to make a sharp turn with a smaller turning radius than the braking turn. I do. HST7 for turning
If the output rotation speed of 0 is reversed at the same speed as that of the forward side, the left and right crawlers 3L and 3R run in opposite directions at the same speed, so that the combine 1 turns sharply with the smallest turning radius on the spot. Act like so. The braking turn,
Gentle swirling, the modes sharp turn is power Sutereba 60 6
As shown in FIG. 7, the tilt angle may be selected . in this case
Does not provide the turning speed lever 53.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B60K 17/04 B60K 17/04 C

Claims (1)

[Claims] 1. A stepless main transmission unit capable of continuously inputting power from a power source and continuously changing a rotation speed from the power source, and an auxiliary transmission unit provided downstream of the main transmission unit.
A traveling speed transmission device in which an output is selectively transmitted to a pair of left and right crawlers; and a power of the main transmission device from a position after an output shaft of a main transmission device of the traveling speed transmission device and before an input shaft of a subtransmission device. And a continuously variable speed traveling direction steering device communicatively connected to a crawler on one side of a pair of left and right crawlers.