JP2001206228A - Steering system for tractor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the steering from the outside of a vehicle body when riding over a ridge between rice fields and when loading/unloading. SOLUTION: A steering lever 3 to be turned clockwise and counterclockwise for interlocked steering is provided at a front side of a vehicle body 2 of a passenger tractor having a steering wheel for steering. The maximum steering angle by this steering lever 3 is set in a smaller area than the maximum steering angle by the steering wheel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a tractor steering device. The present invention can be used as a steering device having a form in which a manually operated steering lever is provided on the front side of a riding tractor or a riding work machine.

[0002]

In a riding work machine such as a combine harvester or a rice transplanter, a driver can ride as a riding body and steer with a steering handle, and a working mechanism is provided in addition to the steering handle. There is a form in which steering can be performed by performing an auxiliary operation from a walking position. However, in this auxiliary steering during walking, the pilot is often located on the front side or the side of the vehicle body, and it is difficult to perform the operation.

[0003]

According to the present invention, a steering lever 3 is provided on the front side of a steerable riding tractor body 2 having a steering handle 1 and which is turned to the left and right so as to be interlocked with steering. The tractor steering device is configured such that the maximum steering angle by the steering lever 3 is set to be smaller than the maximum steering angle by the steering handle 1.

[0004]

The steering of the work machine body 2 is performed by operating the steering handle 1 at the position where the operator is on board. In a case where the vehicle body 2 is to be moved over a ridge or loaded / unloaded from / to the vehicle, when the operator performs a steering operation in a posture of getting off the vehicle body 2, the steering lever 3 is turned left and right from the front of the vehicle body 2. Steering by moving operation.

Since the maximum steering angle by operating the steering lever 3 is set to be smaller than the maximum steering angle by operating the steering handle 1, safe steering without excessive steering angle is eliminated. The vehicle can be driven. For this reason, even if the operator is in the position and posture
This facilitates steering.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention can be applied to a tractor having a working machine mounted on a rear portion of a vehicle body, a seedling planting machine, management work, and the like. Description will be made based on the drawings illustrating a seedling planting machine.

[0007]

First Embodiment Referring to FIGS.
Has a front wheel 5 steerable by a steering handle 1 on a front steering post 4 and a rear wheel 7 disposed behind a cockpit 6, and an engine mounted below the cockpit 6. 8 is a four-wheel drive running mode that can run in conjunction with each other. Reference numeral 9 denotes a step floor, 10 denotes a pair of left and right steering brake petals, and steer brakes (not shown) provided on the left and right rear wheels 7 respectively. Reference numeral 11 denotes a traveling clutch petal, and reference numeral 12 denotes a shift lever.

A lift link 13 comprising a pair of upper and lower parallel links is provided at the rear side of the vehicle body 2 so as to be vertically rotatable by a lift cylinder 14 which expands and contracts by hydraulic pressure. The seedling plant 16 of a multi-row type is connected. The seedling plant 16 is interlocked via a PTO shaft (not shown) on the vehicle body 2 and operates to plant seedlings. 17
Is a fertilizer application, which is mounted on the rear part of the vehicle body 2.

The seedling plant 16 has a center float 19 and a side float 20 arranged below the seedling planting frame 18 to support the weight of the seedling plant 16 and level the soil while sliding on the soil surface. At the rear, a seedling planting device 21 for separating and holding the seedlings and planting them on the level soil surface can be arranged to perform multi-row planting. On the upper side, there is provided a seedling tank 22 for accommodating matted seedlings raised in a mat shape and reciprocating left and right and feeding the seedlings to a seedling opening at the lower rear. By operating the planting claw portion of the seedling planting device 21 at the seedling outlet of the seedling tank 22, a predetermined number of seedlings are separated and held and planted.

Reference numeral 23 denotes an auxiliary seedling mounting table provided on the front portion of the vehicle body 2 for accommodating mat seedlings to be supplied to the seedling tank 22. 24
Is a steering marker. Reference numeral 23 denotes an auxiliary seedling mounting table provided on the front part of the vehicle body 2 for accommodating mat seedlings to be supplied to the seedling tank 22. 24 is a steering marker.

A steering arm 26 integral with an axle case 25 of a pair of left and right front wheels 5 and a pitman arm 27 at the front of the vehicle body 2 are connected by a tie rod 28, and the power steering is operated by operating the steering handle 1. Through the arm shaft 29
, The pitman arm 27 integral with the arm shaft 29 can be rotated, and the front wheels 5 can be steered.

The steering lever 3 is mounted on the pitman arm 27.
On the front side of the vertical shaft 30 in the form of a cross shaft, it is rotatable in the left-right direction A around a vertical shaft 30 portion, and around the horizontal shaft 34 portion in the front-rear direction B.
To be able to rotate. By turning in the left-right direction A, the front wheel 5 can be steered by turning the pitman arm 27. In turning in the front-back direction B, the steering lever 3 is moved in and out.

The vertical shaft 30 and the horizontal shaft 34 in the form of a cross shaft can rotate integrally around the vertical shaft 30.
It is pivotally supported at the front end of the vehicle body 2 at part 0. The base of the steering lever 3 is supported around the horizontal axis 34 so as to be rotatable in the front-rear direction B. The engagement arm 31 protruding from the base of the steering lever 3 is engaged with the arm groove 32 of the pitman arm 27. The pitman arm 27 can be rotated by the steering lever 3.

When pivoting in the left-right direction A as the steering posture C by leaning forward against a spring (not shown), the fork-shaped angle restricting tool 38 protrudes from the front end of the vehicle body 2. Touching,
The steering angle range of the front wheel 5 by the steering lever 3 is limited. The maximum steering angle of the turning angle restrictor 38 is set smaller than the maximum steering angle of the steering handle 1.

When the steering lever 3 is released, the steering lever 3 can be raised from the steering posture C to the rear storage posture D along the steering post 4 by a spring force. A grip 35 is formed at the tip of the steering lever 3, a brake lever 36 is provided on one side, and a clutch lever 37 is operably provided on the other side.

At the time of seedling planting operation, when the driver gets on the cockpit 6 and drives, the steering lever 3 is in the storage position D,
The engagement arm 31 is out of the arm groove 32.
By operating the steering handle 1, the left and right front wheels 5 are steered and linked via the pitman arm 27, the tie rods 28 and the like, and the steering angle can be largely reduced.

When the operator steers with the steering lever 3 such as when traveling over a ridge, the steering lever 3 in the stowed position D is tilted forward from the front side of the vehicle body 2 to obtain the steering position C. By engaging the joint arm 31 with the arm groove 32 and operating the steering lever 3 in the left-right direction A, the pitman arm 27 can be turned and the left and right front wheels 5 can be steered.
At this time, since the steering lever 3 is restricted by the steering angle restricting tool 38 to a safe area where the maximum steering angle is the minimum necessary, the steering lever 3 is moved in a steering angle area smaller than the steering angle by the steering handle 1. Steering can be restricted.

[0018]

Second Embodiment FIGS. 5 and 6 are different from the above embodiments in that the operating position of the steering lever 3 is a stop position E, a standing position along the steering post 4 is a stop position E, and a step floor further rearward. The accommodation posture D along 9 is set. The steering lever 3 is attached to the vehicle body 2 so that the horizontal shaft 34 protrudes laterally at a position deviated left and right from the front of the center of the vehicle body 2. Arms 39 and 40 are provided on both left and right sides of the horizontal shaft 34, and link rods are provided between the arms 39 and 40 and the arm 41 of the clutch petal 11 and the arm 42 of the brake petal 10 facing the rear. 43,4
Connect with 4.

When the steering lever 3 is set to the steering posture C and the hand is released during the operation, the steering lever 3 is returned to the stop position E by the spring force, and the link rods 43 and 44 are moved.
As a result, the interlocked clutch petals 11 and brake petals 10 are rotated, the clutch is disengaged, the transmission of the front wheels 5 and the rear wheels 7 is cut off, and the left and right steering brakes are simultaneously braked. When the steering lever 3 is operated to the steering posture A, these traveling clutches are engaged, and the left and right steering brakes are released.

When the driver releases the fattening of the steering lever 3 due to a fall or the like during the steering by the steering lever 3, the running clutch is automatically disengaged and the left and right steering brakes operate. Safety can be achieved. When the steering lever 3 is lowered to the storage position D, the steering lever 3 can be turned by, for example, disconnecting the link rods 43, 44 from the arms 39, 40 of the horizontal shaft 34.

[0021]

Third Embodiment FIG. 7 is different from the above embodiment in that the steering by the steering handle 1 when the vehicle body 2 reaches a ridge or the like is facilitated. The steering switch SW1 is turned on in advance, and the rotation angle 45 serving as a steering angle sensor detects this angle by operating the steering handle 1 for a predetermined time or more, and the motor 47 is electrically driven by the output from the controller 46. By driving the power steering 48 composed of a torque generator, the turning angle of the front wheel 5 is set to be larger than that in the normal state.

The control of the power steering 48 is carried out in a traveling transmission mode in which a main transmission can be transmitted by providing a hydraulic stepless transmission or the like, when the seedling planting operation by the seedling planting apparatus 16 enters a turning steering state. . The steering switch SW1 is manually turned ON when the power steering 48 is controlled as described above.
When the steering switch SW1 is in the seedling operation state by the main speed change and the steering brake petal 11
The power steering can be more easily controlled by automatically turning on when a one-brake is operated by stepping on to enter a turning stroke.

[0023]

Fourth Embodiment In FIG. 8, the difference from the above example is that, when the shift lever 12 is operated at the neutral position N, the left and right steering brakes are simultaneously braked by operating to the neutral brake position BL. The brake position can be fixed. By operating the transmission lever 12, the on / off of the traveling clutch and the on / off of the left and right steering brakes are simultaneously performed. Safety when loading and unloading the seedling transplanter to and from the truck bed can be achieved.

The speed change lever 12 may be configured to double as a clutch lever. Around the speed change shaft 51, it can be operated and rotated back and forth along the lever guide 50 of the operation panel 49, and when it is operated to the front side, it can run forward as the forward position F,
When operated backward, the vehicle can travel backward as the forward position R. The intermediate position N is a crank shape, and a neutral brake position BL on one side of the neutral position N is formed so that the shift lever 12 can be guided and engaged.

A brake switch SW2 is provided on the lever guide 50 at the neutral brake position BL. The brake switch SW2 is turned on by pressing the shift lever 12 to operate the electromagnetic valve for braking, and the brake circuit is operated by a hydraulic circuit. Is to brake. When shifting gears, the shift lever 12 is moved from the brake position BL to turn off the brake switch SW2 to release the left and right steering brakes so that the vehicle can be shifted.

In a mode in which the transmission lever 12 is replaced with a clutch lever, the traveling clutch is disengaged at the neutral position N, and the traveling clutch is engaged at the forward position F or the reverse position R. Further, a sub-transmission lever may be used in place of the transmission lever 12.

[Brief description of the drawings]

FIG. 1 is a plan view of a steering lever unit.

FIG. 2 is a side view thereof.

FIG. 3 is a side view of the seedling planter.

FIG. 4 is a plan view thereof.

FIG. 5 is a plan view of a steering lever portion showing another embodiment.

FIG. 6 is a side view thereof.

FIG. 7 is a block diagram of a steering handle portion showing a partly different embodiment, and its flowchart.

FIG. 8 is a plan view and a side view of a transmission lever guide portion showing a partially different embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steering handle 2 Riding tractor body 3 Steering lever

Claims (1)

[Claims] 1. A steering lever 3 which is turned to the left and right to steer and interlocks is provided at the front side of a steerable riding tractor body 2 having a steering handle 1, and a maximum steering by the steering lever 3 is provided. A tractor steering device in which the angle is set to be smaller than the maximum steering angle by the steering handle 1.