JP2001328557A - Traveling device for working vehicle and the like - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a traveling device for a working vehicle, allowing free setting of a turning condition during steering turning operation in various modes by inputting from a hydraulic continuously variable transmission to planetary gear mechanisms mounted in a transmission case. SOLUTION: The traveling device for the working vehicle comprises the transmission case 2 in which a gear train is mounted for steering turning with a pair of right and left planetary gear mechanisms 1 and a constant input or traveling power by a hydraulic continuously variable transmission 3 is inputted to the transmission case 2, containing a hydraulic pump 5 and a pair of right and left hydraulic motors 6 constituting a hydraulic continuously variable transmission 4 for inputting control power individually to the pair of right and left planetary gear mechanisms 1 during steering turning or a pair of right and left hydraulic pumps 10 and a hydraulic motor 11 constituting a hydraulic continuously variable transmission 9, and a steering clutch 7 in a passage for transmitting traveling power to the planetary gear mechanisms 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling device for a working vehicle or the like, and more particularly, to a planetary gear mechanism provided in a traveling transmission case, which is provided with a hydraulic stepless transmission for inputting control power for steering turning. Belonging to such fields as

[0002]

2. Description of the Related Art When a work vehicle or the like travels, a pair of left and right gears are arranged in a gear train of a traveling transmission case for inputting power from a hydraulic motor of a hydraulic continuously variable transmission. When the steering section of the traveling section is driven by the left and right traveling crawlers by the steering action of the planetary gear mechanism, as in the related art, a single hydraulic type continuously variable transmission different from the traveling system is used for the planetary gear mechanism. When the control power of forward / reverse rotation is input by the hydraulic motor, the increase / decrease ratio of the left and right traveling parts is constant, and the average vehicle speed during turning is constant, but the speed outside the turning part of the traveling part is increased. Therefore, the turning speed increases, which is dangerous. Usually, there is a problem that a mechanism for reducing the turning speed is complicated, and
Since the turning state (turning radius) is always constant with respect to the operation angle of the steering or the like, there is a difficulty in arbitrary selection of turning conditions.

[0003]

A first aspect of the present invention is a hydraulic stepless transmission for inputting traveling power to a transmission case 2 having a gear train for steering and turning by a pair of left and right planetary gear mechanisms 1. In addition to the device 3, a pair of left and right planetary gear mechanisms 1 are provided with a hydraulic pump 5 and a pair of left and right hydraulic motors 6 as a hydraulic stepless transmission 4 for individually inputting control power during steering and turning. A traveling device such as a work vehicle is characterized in that:

[0004] The invention of claim 2 is a system for transmitting the input of the traveling power to the transmission case 2 by the hydraulic continuously variable transmission 3 to the pair of left and right planetary gear mechanisms 1.
A traveling device for a working vehicle or the like according to claim 1 is provided with a steering clutch 7 for turning on and off the transmission.

According to a third aspect of the present invention, a fixed input to the transmission case 2 is provided, and a transmission path from the input to the pair of left and right planetary gear mechanisms 1 via the auxiliary transmission portion 8 is provided. A pair of left and right hydraulic pumps (10) and hydraulic motors (11) as hydraulic stepless transmissions (9) for separately inputting control power during steering turning to the planetary gear mechanism (1). Of a traveling device such as a work vehicle.

[0006]

According to the first aspect of the present invention, the traveling power is input to the transmission case 2 by the hydraulic stepless transmission 3 when the work vehicle or the like is running, and the left and right components installed in the case 2 are input by the input. The transmission of the traveling system is performed via the pair of planetary gear mechanisms 1, and the pair of left and right hydraulic motors 6 are driven by the hydraulic pump 5 of the hydraulic continuously variable transmission 4 different from the traveling system during the steering and turning operation. By inputting the power for steering and turning control separately to the pair of left and right planetary gear mechanisms 1, various types of steering and turning operations, for example, a normal brake turning by stopping the running portion inside the turning and running inside the turning. Mild turning that makes a large turn due to partial deceleration, spin turning that makes a small turn due to reversal of the running part inside the turn, and the like can be performed.

According to the second aspect of the present invention,
When a work vehicle or the like travels, driving power is input to the transmission case 2 by the hydraulic continuously variable transmission 3, and the input transmission is turned on and off to transmit power to the left and right steering clutches 7 for steering and turning. By transmitting the traveling system from the steering clutch 7 via the pair of left and right planetary gear mechanisms 1, the planetary gear mechanism 1 is controlled by the hydraulic stepless transmission 4 for various types of steering turns. In addition to the operation, simple steering direction correction and fine turning can be applied by the steering clutch 7.

[0008] According to the third aspect of the present invention, with the above configuration,
A constant traveling power is input to the transmission case 2 when the work vehicle or the like travels, and the transmission of the traveling system is transmitted from the auxiliary transmission unit 8 through the pair of left and right planetary gear mechanisms 1, which inputs the input into the transmission case 3 or more mechanically. When performing the steering and turning action,
By driving the hydraulic motor 11 by the pair of left and right hydraulic pumps 10 of the hydraulic stepless transmission 9, the power for steering and turning control is separately input to the pair of left and right planetary gear mechanisms 1, so that the auxiliary transmission unit 8 is provided. , And various types of steering and turning operations can be performed.

[0009]

According to the first aspect of the present invention, as described above,
In a work vehicle or the like, the traveling power is transmitted through the pair of left and right planetary gear mechanisms 1 by the input of the traveling power from the hydraulic continuously variable transmission 3 and driven by the hydraulic pump 5 of the hydraulic continuously variable transmission 4. The pair of left and right hydraulic motors 6 respectively input steering power to the pair of left and right planetary gear mechanisms 1 to perform various types of steering / turning operations. Arbitrary input and arbitrary setting of the turning state with respect to the operation angle of the steering and the like can be performed, and since there is no need to reduce the turning speed unlike in the related art, a complicated link or the like is not required and the configuration can be simplified. .

According to the second aspect of the present invention, as in the above operation, the input of running power by the hydraulic continuously variable transmission 3 in the work vehicle or the like is performed by turning the left and right steering clutches 7 on and off.
And the traveling system is transmitted through a pair of left and right planetary gear mechanisms 1 so that various types of steering turning can be acted on by the planetary gear mechanism 1 and simple direction correction and fine turning can be performed. By the steering clutch 7, the same operation as that of the conventional structure without using the planetary gear mechanism 1 can be performed.

According to the third aspect of the present invention, as described above, the input of a constant traveling power in a working vehicle or the like is performed by the auxiliary transmission unit 8.
And the transmission of the traveling system via a pair of left and right planetary gear mechanisms 1 and a pair of left and right planetary gear mechanisms by a hydraulic motor 11 driven by a pair of left and right hydraulic pumps 10 of a hydraulic continuously variable transmission 9. By driving the steering gears 1 separately so as to be able to perform steering / turning control to perform various types of steering / turning operations, it is possible to perform a multi-stage traveling speed change by the mechanical sub-transmission unit 8 and to perform a left-right steering / turning state. Arbitrary settings can be made possible.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below with reference to the accompanying drawings. 9 and 10 show the entire structure of the combine, in which a traveling device 14 in which a pair of left and right traveling crawlers 13 that travel on the soil surface is arranged below the chassis 12 is provided. A grain tank 16 for threshing grain culms supplied by being pinched and conveyed to the feed chain 15, sorting and collecting the threshed grains, and temporarily storing the grain, and the tank 1.
A threshing device 18 is provided, which is provided with a threshing auger 17 for discharging the grains stored in 6 to the outside of the machine.

In front of the threshing device 18, a weeding body 19 for weeding the planted grain culm from the front end side, a raising part 20 for causing the weeded grain culm, and a cutting blade part for cutting the caused grain culm. 21 and a mowing device 23 having a cereal stalk transport portion 22 for transporting the harvested cereal stem backward and delivering it to the feed chain 15 by means of a hydraulically driven telescopic cylinder 24 so as to be able to move up and down on the soil surface. It is suspended from the front end of the chassis 12.

An operating device 25 for controlling the operation of the combiner and an operating seat 26 for operation are provided on one side of the reaper 23, an engine 27 is mounted below the operating seat 26, and the engine 27 is mounted on the rear side. While arranging the Glen tank 16,
A cabin 28 that covers the operation device 25 and the operation seat 26 is provided, and the traveling device 14, the threshing device 18, the reaper 2
3, an operating device 25, an engine 27, and the like constitute a combine body 29.

The traveling crawler 1 is provided at the front end of the chassis 12.
A hydraulic pump 30 and a hydraulic motor 31 for mounting a traveling transmission case 2 for driving the transmission case 3 and for supplying traveling power to the transmission case 2 as shown in FIG.
And a hydraulic continuously variable transmission 3 that causes the body 29 to be steered and turned by a hydraulic pump 5 and a pair of hydraulic motors 6.

An input pulley 32a fixed to a hydraulic input shaft 32 connecting the hydraulic pump 30 and the hydraulic pump 5, and an output pulley 33 fixed to an output shaft 33 of the engine 27.
a and d are interlockingly connected via a transmission belt 34 so as to be drivable. An output section of a hydraulic motor 31 driven by the traveling hydraulic pump 30;
And the input shaft 35 as the first shaft arranged in
The input shaft 35 is provided with three transmission drive gears 36 for switching the speed between low, medium, and high speeds as the auxiliary transmission portion 8 by rotating the shaft so as to be slidable left and right by splines or the like.

A low-speed driven gear 38 as a working speed (low) and a medium-speed driven as a working speed (high) are meshed with the speed-changing shaft 37 as a second shaft to be engaged with each other by sliding the speed-change drive gear 36 left and right. The gear 39 and the high-speed driven gear 40 as the running speed are configured to be fixed on the shaft. A steering center gear 41 meshing with the middle-speed driven gear 39 is fixed to a sun gear shaft 42 as a third A shaft, and left and right sun gears 43 are fixed to both ends of the sun gear shaft 42, respectively. A pair of left and right planetary gear mechanisms 1 are disposed around the sun gear 43, respectively.

The pair of left and right planetary gear mechanisms 1 rotatably support three left and right planetary gears 44 meshing with the outer periphery of the left and right sun gears 43 at equal intervals by left and right carriers 45, respectively. A left and right internal ring gear 46 meshing with the outer periphery 44 is provided, and a left and right steering shaft 47 as a third B axis extending outward from the left and right carriers 45 is disposed coaxially with the sun gear shaft 42. Configuration.

Left and right steering drive gears 48 are fixed to the other ends of the left and right steering shafts 47, respectively.
The left and right reduction gears 50 fixed to one ends of left and right axles 49 as a fourth shaft mesh with each other, and the left and right reduction gears 50 are attached to the other ends of the axles 49 protruding outward from the case 2. The left and right driving wheels 51 for driving the traveling crawler 13 are fixed to the shaft.

From the steering / turning hydraulic pump 5 via an open / close switching solenoid valve 52 for opening / closing a hydraulic circuit by switching between 4 ports and 2 positions, switching between forward and reverse rotation by switching between left and right 4 ports and 3 positions. Are connected to a pair of left and right hydraulic motors 6 via a forward / reverse switching electromagnetic valve 53, and the left and right steering operation gears are axially fixed to a hydraulic output shaft 54 disposed in the case 2 of the left and right hydraulic motors 6. 55 and a steering control gear 56 provided on the outer periphery of the left and right ring gears 46 are meshed with each other.

A cutting drive pulley 92 fixed to the other end of the input shaft 35 projecting outward from the case 2.
A transmission belt 94 for driving the mowing device 23 is stretched and stretched between the mowing device 23 and the mowing input pulley 93 provided at the mowing device 23. By adjusting the angle of rotation of the swash plate by the hydraulic pump 30 of the traveling hydraulic continuously variable transmission 3 driven by the engine 27, the power obtained by performing forward / reverse rotation and rotation speed control of the hydraulic motor 31 is supplied to the input shaft 35. At the same time, the transmission drive gear 36 supported on the input shaft 35 is slid to engage with the low, medium and high speed transmission gears 38, 39, 40 fixed to the transmission shaft 37, so that the auxiliary Control is performed to switch between the working speed (low), the working speed (high), and the traveling speed as the transmission unit 8.

The power shifted by the shift shaft 37 is
The medium-speed driven gear 39 meshes with the steering center gear 41 to be transmitted to the sun gear shaft 42 in conjunction with driving the left and right sun gears 43 fixed to the sun gear shaft 42, and the left and right steering shafts are driven by the pair of left and right planetary gear mechanisms 1. Steering drive gear 4 fixed to 47
The gears 8 mesh with the left and right reduction gears 50 and are transmitted to the left and right drive wheels 51 fixed to the left and right axles 49, respectively.

The hydraulic continuously variable transmission 4 for steering and turning, which is driven by the engine 27 simultaneously with the hydraulic pump 30.
Adjustment of the angle of the rotary swash plate by the hydraulic pump 5
A pair of left and right forward / reverse switching solenoid valves 5 via an opening / closing switching solenoid valve 52
3 through the right and left steering gears 55 fixed to the hydraulic output shaft 54 of the hydraulic motor 6, and the left and right ring gears 46.
To the steering control gear 56.

In normal traveling, the driving force of the hydraulic motor 31 is transmitted from the speed change drive gear 36 to the medium speed driven state while the drive of the steering control hydraulic motor 6 is stopped and the left and right ring gears are stationary. The gear 39, the steering center gear 41, and the left and right sun gears 43 are transmitted in this order at the same rotational speed.
The transmission of the same rotational speed in the left and right same rotational direction to the left and right drive wheels 51 via the planetary gear 44, the carrier 45, and the steering shaft 47 of the pair of left and right planetary gear mechanisms 1
You can drive straight ahead and back.

Next, with the driving of the traveling hydraulic motor 31 stopped and the left and right sun gears 43 stationary,
The left or right hydraulic motor 6 on the outer side of the rotation is driven to rotate forward by switching the forward / reverse switching solenoid valve 53 to drive the planetary gear mechanism 1
By rotating the drive shaft 51 forward through the planetary gear 44, the carrier 45, and the steering shaft 47, a so-called normal brake turning can be performed.

Next, with the driving of the hydraulic motor 31 stopped and the left and right sun gears 43 stationary, the hydraulic motor 6 on the outer side of rotation is rotated forward and the hydraulic motor 6 on the inner side of rotation is rotated.
Are driven in reverse rotation to drive the driving wheels 51 through the planetary gear mechanism 1.
Are rotated forward and backward, respectively, so-called spin turning with a small turning radius can be performed.

Next, while the hydraulic motor 31 is driven, the hydraulic motor 6 on the inner side of the turning is driven to rotate in the reverse direction, and the driving wheel 51 is rotated through the planetary gear mechanism 1 in the deceleration forward direction, so-called turning. A mild turn with a large radius can be performed. As described above, the rotation speed of the hydraulic motor 6 is controlled by adjusting the angle of the rotary swash plate by the steering control hydraulic pump 5, and the forward / reverse switching of the rotation direction is performed by the forward / reverse switching solenoid valve 53. Since any input to the pair of left and right planetary gear mechanisms 1 and any setting of the turning state with respect to the operation angle of the steering or the like can be made, various types of steering turning action can be performed.

In the traveling transmission case 2 shown in FIG. 1, the gear arrangement is partially changed.
As shown in FIG. 2, a middle speed driven gear 39 fixed to a speed change shaft 37 as a second shaft, and left and right steering center gears 4 respectively fixed to left and right divided sun gear shafts 42 as a 3A shaft.
1 and an intermediate shaft 57 is arranged.

The intermediate shaft 57 is provided with an intermediate center gear 58 which meshes with the middle speed driven gear 39 and the intermediate center gear 5.
Left and right intermediate side gears 59 which are rotatably rotated on both outer sides of the gear 8
Left and right steering clutches 7 for turning on and off the connection with
The left and right intermediate side gears 59 and the left and right steering center gears 41 are configured to mesh with each other.

With this configuration, the driving system is driven by the pair of left and right planetary gear mechanisms 1 through the left and right steering clutches 7 for turning on and off the driving power of the driving hydraulic motor 31. By doing so, various forms of steering turning can be acted on by the planetary gear mechanism 1, and simple direction correction, fine turning and the like can be acted on by the steering clutch 7 as in the prior art.

In the traveling transmission case 2 shown in FIG. 1, the hydraulic system is changed as shown in FIG.
As shown in the figure, the output pulley 33a fixed to the output shaft 33 of the engine 27 and the input pulley 60 fixed to the input shaft 35 as the first shaft of the transmission case 2 can be driven via the transmission belt 61. It is configured by interlocking connection.

The steering control gear 56 provided on the ring gear 46 of the pair of left and right planetary gear mechanisms 1 and the hydraulic output shaft 62 of the hydraulic motor 11 driven by the pair of left and right hydraulic pumps 10 of the hydraulic stepless transmission 9. The left and right output control gears 63, each of which is axially stopped, are configured to mesh with each other via left and right intermediate gears 65.

With this configuration, constant traveling power is input from the engine 27 to the traveling transmission case 2, and the low-, medium-, and high-speed transmissions of the transmission drive gear 36 and the transmission shaft 37 of the input shaft 35 are transmitted. The traveling system is driven via the pair of left and right planetary gear mechanisms 1 through the auxiliary transmission portion 8 including the gears 38, 39, and 40, and the planetary gear mechanisms 1 are separately driven by the pair of left and right hydraulic motors 11. By performing various types of steering turning operations, it is possible to perform multi-stage traveling shifts by the subtransmission unit 8 and arbitrarily set a turning state.

In the traveling transmission case 2 shown in FIG. 1, the pair of left and right planetary gear mechanisms 1 are separately driven to perform various types of steering and turning operations. As shown in FIG. 4, the means for setting the output conditions of the pair of left and right hydraulic motors 6 is provided with an adjustment switch 65 for slowly and rapidly adjusting the turning speed, a changeover switch 66 for switching the field conditions between wet and dry fields, and the like. Let it.

With such a configuration, it has conventionally been difficult to arbitrarily set the turning state by the operator, but the optimal setting is facilitated by the adjustment switch 65 and the changeover switch 66, and the operability is improved. improves. Further, in the traveling transmission case 2 shown in FIG. 1, a part of a path for inputting power for steering and turning control to each of the pair of left and right planetary gear mechanisms 1 is partially changed.
As shown in FIG. 5, the hydraulic output shaft 54 of the hydraulic motor 6 on the left side is extended, and one side of the switching clutch 67 for switching the rotation direction between forward and reverse together with the steering operation gear 55 fixed to the output shaft 54 is connected. It is configured with the shaft stopped.

A steering reverse operation gear 68 is axially fixed to the other side of the switching clutch 67 having one side axially fixed to the hydraulic output shaft 54,
The steering reverse operation gear 68 and the right ring gear 46
And the steering control gear 56 provided through the intermediate gear 69 is interlocked and linked. The switching clutch 67 may be provided on either the left or right side.

With such a configuration, the left and right independent outputs of the hydraulic motor 6 for steering and turning the pair of left and right planetary gear mechanisms 1 are input independently, and the output of one hydraulic motor 6 is By turning on and off, the planetary gear mechanism 1 can be switched between forward and reverse rotation at a constant rate, so that only one hydraulic motor 6 is output in the rapid turning mode in which spin turning or the like that requires large horsepower is performed. As a result, the horsepower loss can be reduced and the control can be simplified, and in the other turning modes, the normal steering turning action can be performed by the left and right hydraulic motors 6.

In the traveling transmission case 2 shown in FIG. 3, the three planetary gears 44 meshing with the left and right ring gears 46 of the pair of left and right planetary gear mechanisms 1 are rotatably supported at equal intervals. Carrier 45
, The steering shaft 47 as the third B axis is extended outward.

The left and right steering drive gears 48 fixed to the other end of the steering shaft 47 and a cutting drive shaft 91 for driving the cutting device 23 disposed in the case 2 are provided in one direction. The right and left mowing drive gears 70 supported by a rotatable rotary clutch 70a are engaged with each other, and the mowing drive pulley 92 is attached to one end of the mowing drive shaft 91 projecting outward from the case 2. Stop and configure.

With such a configuration, the output for driving the mowing device 23 can be held by the rotary clutch 70a on the side where the rotational speed of the left and right steering drive gears 48 is high, so that the traveling speed is reduced as in the prior art. The raising unit 2 for securing the high-speed reaping speed synchronized with the direction and performing the direction correction and the like.
Performance degradation such as 0 can be prevented.

It should be noted that in most of the general-purpose combiners in which the steering and turning action is driven by a left and right independent hydraulic continuously variable transmission, the drive of the reaper 23 is transmitted from the engine in most cases. Nothing that is configured to transmit power from the mission case 2 as in the present invention is found.

In the traveling transmission case 2 shown in FIG. 3, the traveling power is changed to a hydraulic system, and the hydraulic power supply for supplying the traveling power to the case 2 as shown in FIG. Hydraulic pump 30 of continuously variable transmission 3
And an output portion of a hydraulic motor 31 driven by the hydraulic pump 30 is operatively connected to an input shaft 35 as a first shaft arranged in the case 2, and the pair of left and right hydraulic systems for steering and turning control is provided. The hydraulic pump 10 and the hydraulic motor 11 of the continuously variable transmission 9 are arranged and configured.

With such a configuration, it is possible to arbitrarily set the left and right rotation speeds and rotation directions during steering turning by operating the three sets of hydraulic continuously variable transmissions 3 and 9, thereby increasing turning variations. In addition, the internal structure of the transmission case 2 can be simplified. When the steering turning hydraulic pump 10 and the hydraulic motor 11 are operated on only one side, as in the conventional case, the forward / reverse ratio is constant, turning conditions are limited, and a speed reduction mechanism during turning and a reverse handle prevention mechanism are provided. Are required, and the structure becomes complicated.

In the traveling transmission case 2 shown in FIG. 2, the hydraulic paths for inputting the power for steering and turning control to the pair of left and right planetary gear mechanisms 1 are partially changed. As shown in FIG. 7, the steering and turning hydraulic pump 5 is connected to a pair of left and right hydraulic motors 6 via a flow dividing valve 71 for adjusting the flow of pressure oil.

With such a configuration, it is possible to set an arbitrary turning condition by changing the ratio of the flow dividing valve 71, and to perform a steering turning action that can cope with various running soil surface conditions. Regardless of the range of the subtransmission portion 8, the operation angle of the steering and the like and the turning radius can be synchronized. It should be noted that, as in the related art, when the range of the sub-transmission unit 8 is switched, the turning radius changes with respect to the operation angle of the steering or the like, so that it is difficult to operate.

In the traveling transmission case 2 shown in FIG. 7, a vehicle speed sensor 72 which engages with the speed change shaft 37 as the second shaft to detect a vehicle speed, and detects a change in an operation angle of a steering or the like. Operation angle sensor 73 and turning mode sensor 7 for detecting a switching position of the turning mode
4 is connected to the flow dividing valve 71 so as to be able to transmit.

With this configuration, when the pair of left and right hydraulic motors 6 is driven from the steering and turning hydraulic pump 5 via the flow dividing valve 71, the amount of distribution by the flow dividing valve 71 is determined by the vehicle speed sensor 72. As the vehicle speed increases, distribution is performed based on the detected values so that the vehicle does not turn sharply even at the same operation angle of steering or the like, thereby enabling turning control in accordance with the vehicle speed.

The distribution amount of the diverting valve 71 is distributed such that the larger the change in the operation angle of the steering or the like based on the detection value of the operation angle sensor 73, the smaller the turning radius is, thereby distributing the turning in accordance with the operation angle. The conditions are made possible, and the turning mode setting position is selected based on the detection value of the turning mode sensor 74, and the turning is performed so as not to shift to the spin turning in the wetland.

In the transmission case 75 shown in FIG. 8, the hydraulic motor 31 of the traveling hydraulic continuously variable transmission 3 is operatively connected to an input shaft 35 as a first shaft. Variable speed drive gear 36 that rotates the shaft as much as possible
And the low, medium, and high speed transmission gears 38, 39, and 40, which are fixed to a transmission shaft 37 as a second shaft.

The intermediate-speed driven gear 39 meshes with an intermediate transmission gear 78 that rotates by the engagement of a synchronous clutch 77 fixed to a turning drive shaft 76 as a third shaft. A steering center gear 80 fixed to a steering shaft 79 as a fourth shaft is meshed and linked, and a left and right dual steering clutch 81 for turning on / off the transmission from the steering center gear 80 is arranged. The steering transmission gear 82 is fixed to the outer periphery of the inner clutch 81a of the dual steering clutch 81.

The steering transmission gear 82 meshes with a large-diameter gear of a double reduction gear 84 rotatably rotating around a reduction shaft 83 as a fifth shaft, and a small-diameter gear of the reduction gear 84 and a sixth gear. An axle gear 86 fixed to one end of an axle 85 as a shaft is meshed and linked, and left and right drive wheels 51 for driving the left and right traveling crawlers 13 are fixed to the other end of the axle 85. .

A hydraulic motor 87b driven by a hydraulic pump 87a of a hydraulic stepless transmission 87 for steering and turning control is connected to the turning drive shaft 76 in an interlocking manner. The left and right turning drive gears 88 are axially stopped, and the transmission from the left and right turning driven gears 89 meshed with the turning drive gears 88 can be turned on and off by the outer clutch 81b of the dual steering clutch 81. . Said 2
The inner clutch 81b and the outer clutch 81b of the continuous steering clutch 81 are restricted from being simultaneously engaged.

Reference numeral 90 denotes a rotation sensor which engages with the shaft ends of the transmission shaft 37 and the turning drive shaft 76 to detect the number of rotations. With such a configuration, when the airframe 29 is steered and turned, the inner clutch 8 of the dual steering clutch 81 is used.
After turning off 1a, the synchronous clutch 77 is disengaged, and at the same time, the turning drive shaft 76 is driven by the steering turning hydraulic motor 87b to transmit the power from the turning drive gear 88 to the turning driven gear 89, thereby performing the dual steering clutch. 81 outside clutch 81
By turning on b, the drive wheel 51 is driven from one steering transmission gear 82 to perform a steering turning action.

During this turning operation, the output rotation speed of the steering shaft 79 and the hydraulic motor 87b is synchronously controlled by the detection value of the rotation sensor 90 or the operation of the synchronous clutch 77, so that the steering center gear 80 and the turning center gear are rotated. Since the rotation speed of the driven gear 89 can be synchronized, the rotation fluctuation after the dual steering clutch 81 is disengaged is small, and a smooth steering turning operation can be performed.

When the rotational speeds of the steering center gear 80 and the rotation driven gear 89 are synchronized, the steering center gear 8
By setting the rotation speed of the rotation driven gear 89 slightly lower than 0, the rotation speed inside the rotation is slightly reduced when the rotation driven gear 89 is connected.
Direction correction and the like can be performed without operating 7b, which facilitates the operation.

[Brief description of the drawings]

FIG. 1 is a diagram showing a turning planetary gear mechanism in a transmission case and a hydraulic path for driving the planetary gear mechanism.

FIG. 2 is a diagram showing a planetary gear mechanism having a steering clutch in the case and a hydraulic path thereof.

FIG. 3 is a diagram showing a planetary gear mechanism using traveling driving and hydraulic pressure in the case, and a cutting drive path.

FIG. 4A is a plan view showing a state of an adjustment switch for slowly or rapidly adjusting a steering turning speed. (B) The top view which shows the state of the changeover switch which switches a field condition to a wetland / dry field.

FIG. 5 is a diagram showing a turning planetary gear mechanism in a transmission case and a hydraulic path for driving the planetary gear mechanism.

FIG. 6 is a diagram showing hydraulic paths for traveling driving and steering turning control in a transmission case.

FIG. 7 is a diagram showing a state in which a flow dividing valve is provided in a drive hydraulic path of the planetary gear mechanism in the case.

FIG. 8 is a diagram showing hydraulic pressure turning by a synchronous clutch and a dual steering clutch in the case.

FIG. 9 is a side view showing the overall configuration of the combine.

FIG. 10 is a plan view showing the overall configuration of the combine.

[Explanation of symbols]

 1. Planetary gear mechanism 2. Mission case 3. 3. Hydraulic continuously variable transmission 4. Hydraulic continuously variable transmission Hydraulic pump 6. Hydraulic motor 7. Steering clutch 8. Sub transmission unit 9. Hydraulic continuously variable transmission 10. Hydraulic pump 11. Hydraulic motor

Claims (3)

[Claims] 1. A hydraulic continuously variable transmission 3 for inputting driving power to a transmission case 2 provided with a gear train for steering and turning by a pair of left and right planetary gear mechanisms 1 is provided. A traveling device for a work vehicle or the like, wherein a hydraulic pump 5 and a pair of left and right hydraulic motors 6 as a hydraulic stepless transmission 4 for inputting control power during steering and turning are separately provided in the gear mechanism 1. . 2. A steering clutch 7 for turning on and off a transmission of transmission of driving power from the hydraulic continuously variable transmission 3 to the transmission case 2 to the pair of left and right planetary gear mechanisms 1. The traveling device for a work vehicle or the like according to claim 1, further comprising: 3. A path for transmitting a constant input to the transmission case 2 from the input to the pair of left and right planetary gear mechanisms 1 via the auxiliary transmission unit 8, and a pair of the left and right planetary gear mechanisms 1 2. The work vehicle according to claim 1, further comprising a pair of left and right hydraulic pumps 10 and a hydraulic motor 11 as a hydraulic stepless transmission 9 for separately inputting control power during steering and turning. Traveling device.