JP2001278104A - Traveling transmission gear of mobile agricultural machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a traveling transmission gear capable of being softly turned without damaging paddy fields. SOLUTION: In a mobile agricultural machine having a working part mounted on the front part of a traveling frame 7, the rotation of an output shaft of a hydrostatic transmission (HST) is transferred to a power take-out part A. The power, the speed of which is changed by HST, is transferred through the medium of steering clutches 1L, 1R and a differential gear 3 to right and left driving axles 34L, 34R. The rotational speed of a differential case 4 of the gear 3 is changed in a stepless manner for the rotational ratio between the axles 34L, 34R to be changed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling transmission device such as a combine and the like, and can be used in a tractor having a steering clutch type transmission device and other mobile agricultural machines.

[0002]

2. Description of the Related Art In a steering transmission in which a steering clutch is disengaged to apply a steering brake, a steering brake is provided outside each of the left and right steering clutches. In some cases, the steering brakes for the respective steering clutches are individually braked to perform steering or turning, or the left and right steering brakes are simultaneously braked to form a parking brake. In such a form, the steering brake has a pair of left and right sides, is complicated, is heavy, and cannot be turned softly.

[0003]

SUMMARY OF THE INVENTION According to the present invention, there is provided a traveling transmission device which is simple in structure, has few failures, and is capable of soft turning without damaging a field, and can drive a working unit in accordance with a vehicle speed. For the purpose of obtaining the device, the following technical measures were taken. That is, in the mobile agricultural machine having the working unit in front of the traveling chassis 7, the rotation of the output shaft of the hydraulic continuously variable transmission HST is transmitted to the power take-out unit A, and the power shifted by the hydraulic continuously variable transmission HST is transmitted. The transmission is transmitted to the left and right traveling axles 34L, 34R via the steering clutches 1L, 1R and the differential device 3, and the differential device 3
The traveling transmission of a mobile agricultural machine is characterized in that the rotation of the differential case 4 is continuously variable and the rotation ratio of the left and right traveling axles 34L, 34R is changed.

[0004]

When driving straight, the left and right traveling axles 34L, 34L
The rotational power shifted by the hydraulic continuously variable transmission HST is transmitted to R, and the machine body travels straight. At this time, rotational power proportional to the vehicle speed is transmitted to the power take-out unit A to drive the working unit.

[0005] Then, a steering operation to one of right and left,
For example, when steering left or turning, by disengaging the left steering clutch 1L, transmission to the left traveling axle is cut off, and left steering can be performed. At this time, by continuously changing the rotation of the differential case 4 of the differential device, the rotation of the differential case 4 is gradually reduced. Therefore, the rotation of the left differential shaft 2L is also reduced, and the rotation of the differential case 4 is reduced to zero. The right axle 2R is rotated in the opposite direction, and the left traveling axle is driven in reverse.

[0006] For this reason, the airframe makes a left turn. or,
Power is transmitted by the same action in right-hand steering and turning travel.

[0007]

According to the present invention, in a mobile agricultural machine having a working unit in front of the traveling chassis 7, the rotation of the output shaft of the hydraulic continuously variable transmission HST is transmitted to the power take-out unit A, and the hydraulic continuously variable transmission HST is used. The power shifted by the steering clutch 1L,
1R, left and right traveling axles 34L, 34 via the differential device 3
R, and the rotation of the differential case 4 of the differential device 3 is continuously variable to change the rotation ratio of the left and right traveling axles 34L, 34R. Therefore, at the time of turning, the left and right traveling axles are provided with a continuous rotation difference, so that the machine body can be turned softly, and the turning can be performed without damaging the field. Further, the rotation of the output shaft of the hydraulic continuously variable transmission HST is transmitted to the power take-out unit A, and the work unit is driven by the power take-out unit A, so that the work unit can be driven in accordance with the vehicle speed. Detailed work can be performed according to the conditions.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A traveling transmission for a combine is exemplified. The combine is mounted on a chassis 7 having a pair of right and left crawler-type traveling devices 6, a threshing device 8, a Glen tank, and a steering device 9.
The cutting frame 14 having the grain stalk raising device 10, the feeding device 11, the cutting blade device 12, the grain stalk transport device 13 and the like is mounted on the shaft 1 above the transmission case 15 in front of the threshing device 8.
The lift cylinder 17 is provided so as to be rotatable up and down around 6, and the up and down movement is performed by expansion and contraction of a lift cylinder 17 by hydraulic pressure between the cutting frame 14 and the chassis 7. The grain stalks cut by the cutting device configured as described above can be transported and supplied to the feed chain 18 of the rear threshing device 8 for threshing.

The traveling transmission case 15 has a hydraulic continuously variable transmission HST on one upper side, and transmits power from a drive shaft 19 of the engine to the input shaft 20. This hydraulic continuously variable transmission HS
T can continuously change the speed from the neutral position to the forward high-speed position or the reverse high-speed position by operating the transmission lever 21 of the control device 9. The output shaft of the hydraulic continuously variable transmission HST is connected to the transmission shaft 22 of the traveling transmission case 15, and the shaft 22 is extended to form a power take-out portion A at the shaft end. Further, a counter shaft 25 is provided in parallel with the shaft 22, and a sub-transmission gear 23 is provided between the shaft 22 and the counter shaft 25.
A subtransmission is configured with a counter gear 24 interposed therebetween, and the power after the shift is transmitted to the gear 27.

The clutch body 28 at the center of the steering clutch shaft 26 is provided with clutch claws 29 of a pair of left and right steering clutch gears 1L and 1R so as to engage with the tension of springs 30L and 30R. The steering clutch gears 1L, 1R are moved outward by the operation of the clutch shifter.
By moving the clutch claw 29 against the clutch claw 29,
By disengaging the L and 29R portions from the clutch body 28, transmission from the clutch shaft 26 to the steering clutch gears 1L and 1R can be cut off.

Each of the steering clutch gears 1L, 1R has counter gears 32L, 3 rotatable with respect to the counter shaft 31.
2R are always meshed with each other, and these counter gears 32L, 32
The sprocket shafts 34L, 34R of the right and left crawler traveling devices 6 are transmitted from the wheel gears 33L, 33R meshed with R. In such a traveling transmission device, the gears 35L, 35R are always meshed with the left and right steering clutch gears 1L, 1R, and a differential shaft 2L integrated with the gear 35L, and a gear 3L.
A differential (differential) device 3 is formed between the 5R and the integral differential shaft 2R. A disk brake 5 is provided on the outer periphery of a differential case 4 bearing the differential shafts 2L and 2R along the rotation direction.
The rotation of the differential case 4 is braked by clamping the disc brake 5 from both left and right sides with a brake shoe 37 by a brake cylinder 36. Reference numeral 38 denotes a brake unit having the brake cylinder 36, the brake shoe 37, and the like, which also serves as a case cover for opening and closing the opening 39 of the traveling transmission case 15.

When the steering clutch 29L is disengaged, the transmission from the clutch body 28 to the left steering clutch 29L is cut off, so that the transmission can be steered to the left by the transmission of the left traveling device 6. When the disc brake 5 is braked in this state, the rotation of the differential case 4 is stopped in accordance with the braking force, and the rotation of the differential shaft 2R driven from the steering clutch gear 1R through the gear 35R causes the differential device 3 to rotate. The reverse rotation of the left differential shaft 2L is transmitted by the action of
L, via the steering clutch gear 1L, etc.,
Can be transmitted and rotated in the direction opposite to the right side, and can turn sharply to the left side.

In the hydraulic circuit 40 for operating the steering clutch and the disc brake, P is a hydraulic pump, T is a tank port, 41 is a lily valve, 42 is a steering control valve,
43 is a steering sensor; 44L and 44R are steering clutch cylinders for shifting the steering clutch gears 1L and 1R;
Reference numeral 5 denotes a brake cylinder that brakes the disc brake 5, 46 denotes an electromagnetic proportional solenoid valve, and 47 denotes a power steering valve that is manually operated. The operation of the electromagnetic proportional solenoid valve 46 is appropriately controlled to a degree of throttle, a speed, and the like by an output from the controller CPU based on detection of various conditions by sensors.

While detecting the harvested culm streak by the steering sensor 43, the cutting direction is controlled by switching the steering control valve 42 to actuate the steering clutch cylinder 44L or 44R to change the culm streak. Run along. At this time, the power steering valve 47 and the electromagnetic proportional solenoid valve 46 are open. Here, at the time of the steering turn, the power steering valve 47 or the electromagnetic proportional solenoid valve 46 is operated in the closing direction, so that the steering clutch cylinder 44 is operated.
The oil overflowing from L or 44R is sent to the brake cylinder 45, and the brake shooter 37 is operated to clamp the disc brake 5 to perform braking. Thus, the rotation of the differential case 4 is braked, and the differential between the differential shafts 2L and 2R is performed.

In the electromagnetic proportional solenoid valve 46, an initial set pressure is changed by a change in current under the condition detected by each sensor (FIG. 4). When the power steering lever is manually operated, the output pressure of the power steering valve 47 is controlled for each set initial pressure (FIG. 5). Therefore, even if the operating angle of the power steering lever is the same, the control pressure of the disc brake can be arbitrarily selected according to the current value of the proportional solenoid, and the turning radius under each condition can be made substantially the same. Can also be restored.

[Brief description of the drawings]

FIG. 1 is a front view of a transmission mechanism of a traveling transmission unit.

FIG. 2 is a side view thereof.

FIG. 3 is a hydraulic circuit diagram of a steering clutch and a brake.

FIG. 4 is a graph showing a relationship between current and initial pressure of an electromagnetic proportional solenoid valve.

FIG. 5 is a graph showing a relationship between an operation angle of a power steering lever and a disc brake control pressure in a controller.

FIG. 6 is a side view of the combine.

[Explanation of symbols]

 Reference Signs List 1 steering clutch 2 differential shaft 3 differential device 4 differential case 5 disk brake

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F16H 48/20 F16H 1/44

Claims (1)

[Claims] 1. A mobile agricultural machine having a working section in front of a traveling chassis 7 that transmits the rotation of an output shaft of a hydraulic continuously variable transmission HST to a power take-out section A and that the hydraulic continuously variable transmission H
The power shifted by the ST is transmitted to the left and right traveling axles 34L, 34R via the steering clutches 1L, 1R and the differential device 3, and the rotation of the differential case 4 of the differential device 3 is steplessly changed to change the left and right traveling axles. A travel transmission device for a mobile agricultural machine, characterized in that the rotational ratio of 34L, 34R is changed.