JPH08310429A - Steering device for tractor - Google Patents

Abstract

PURPOSE: To facilitate steering linkage of steered wheels by connecting a hydraulic cylinder to steering arms of right and left wheels with a steering rod and mounting a cylinder turn stop mechanism for stopping turning movement of the hydraulic cylinder and performing steering motion between an axle housing and the hydraulic cylinder. CONSTITUTION: Left and right both end parts of a piston rod 5 of a hydraulic cylinder 3 are fitted in a fitting seat 32 in left and right both end parts of a front axle housing 2 by a bracket 33. A bracket 34 is fixed in an intermediate part of the hydraulic cylinder 3 leaving a proper space and between this bracket 34 and a steering arm 6 on a final case mounted opposite outwardly to the bracket 34 is connected by a steering rod 7 and front wheels are turned through the steering rod 7 by lateral movement of the hydraulic cylinder 3. Turning movement around a piston rod 5 of the hydraulic cylinder 3 is regulated by fitting a recessed part 40 of a guide piece 39 of a cylinder stopping mechanism 8 to a guide rod 38 when this hydraulic cylinder 3 is moved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steering device for steering wheels of a tractor.

[0002]

2. Description of the Related Art In a steering system using a hydraulic cylinder mechanism, a hydraulic cylinder is mounted on a vehicle body side along an axle housing, and a piston in the hydraulic cylinder moves laterally. Although it is connected to the steering arms on the steering wheels on both the left and right sides, in such a configuration, the axle housing swings up and down around the center pivot with respect to the vehicle body like a tractor to roll the vehicle body. Is difficult to use.

[0003]

According to the present invention, a piston rod 5 having a fixed piston 4 is provided in a hydraulic cylinder 3 along an axle housing 2 having steerable wheels 1 at both left and right ends. The hydraulic cylinder 3 hydraulically operated with respect to the piston rod 5 and the steering arms 6 of the left and right wheels 1 are connected by a steering rod 7, and the hydraulic pressure is provided between the axle housing 2 and the hydraulic cylinder 3. A tractor steering device is provided with a cylinder rotation stopping mechanism 8 for stopping the rotation of the cylinder 3 and interlocking with the steering.

[0004]

[Operation and Effect of the Invention] By steering the steering wheel, the oil in the hydraulic cylinder 3 is supplied and discharged,
The hydraulic cylinder 3 is moved to the left and right steering sides with respect to the piston 4 in the fixed position. The cylinder rotation stopping mechanism 8 between the hydraulic cylinder 3 and the axle housing 2 controls the hydraulic cylinder 3 in a steering manner to prevent its rotation. With the movement of the hydraulic cylinder 3, the steering arm 6 is steered and rotated via the steering rods 7 on the left and right, so that the wheels 1 on the left and right are steered.

In the structure of such a steering device, since the piston rod 5 side for guiding the hydraulic cylinder 3 to the left and right is mounted along the axle housing 2,
Even if the axle housing 2 swings or rolls with respect to the vehicle body, the hydraulic cylinder 3 is always maintained in a certain relational position with the axle housing 3 to enable the steering of the wheels 1. , This hydraulic cylinder 3
Since the steering rod 7 is connected between the steering arm 6 and the steering arm 6, the steering rod 7 can be lengthened to reduce the angle change during steering, and the hydraulic cylinder 3 rotates. Since it is regulated by the cylinder rotation stop mechanism 8, an accurate steering interlocking structure becomes easy.

[0006]

1 to 5, a tractor vehicle body includes a pair of left and right pipe frames 11 between a clutch housing 9 integral with a front engine E and a transmission case 10.
Front axle bracket 12 on the front.
And has a front axle bracket 12 on the lower side.
And has a front axle housing 2 on the lower side.
Is swingably supported around the center pivot metal 13, and the rear axle housings 2 on the left and right sides are provided at the rear.
1 is provided. Reference numeral 14 denotes a final case that is provided on both left and right ends of the front axle housing 2 so as to be steerable around a steering pin 36, has a steering arm 6, and has a lower end on which a front wheel shaft 15 is mounted. Have.

Reference numeral 16 is a final case which is provided around the steering pins 37 on both the left and right ends of the rear axle housing 21 so as to be steerable. The final case 16 has a steering arm 26 and a rear wheel shaft 17 on which a rear wheel 22 is mounted. Have. 23 is the rear wheel 22
A hydraulic cylinder for steering the vehicle. The left and right ends of a piston rod 25 having the piston 24 and the steering arm 26 are connected by a rod 27, and the piston 24 is moved rearward with respect to the hydraulic cylinder 23. It is a configuration capable of steering the wheels 22. 28 is a mounting seat for mounting the hydraulic cylinder 23 on the vehicle body such as the mission case 10;
Reference numeral 29 is a nipple for supplying and discharging hydraulic pressure.

Reference numeral 18 is a cockpit in the cabin 19, and 20 is a steering wheel. When the steering wheel 20 is operated, a hydraulic cylinder 23 for steering the front wheel 1 which is independently operated together with the hydraulic cylinder 23 is provided in the front axle housing 2 through a power steering mechanism using hydraulic pressure such as an orbit roll. The final case 14 of the left and right front wheels 1 is steered by the left and right movements of the hydraulic cylinder 3 via the steering rod 7, the steering arm 6, and the like.

The piston rod 5 fitted inside the hydraulic cylinder 3 has a piston 4 in the center and is slidable in the axial direction, and is fitted and fixed to both left and right ends of the hydraulic cylinder 3. It is possible to move the hydraulic cylinder 3 to the left and right by supplying and discharging the hydraulic pressure from the nipple 30 to both left and right sides inside the hydraulic cylinder 3 with the piston 4 as a boundary so that the hydraulic cylinder 3 is slidably and closely fitted by the cylinder cap 31. it can.

The left and right ends of the piston rod 5 of the hydraulic cylinder 3 are attached to the mounting seats 32 at the front left and right ends of the front axle housing 2 by brackets 33. A bracket 34 is fixed to the lower side of the hydraulic cylinder 3 at an appropriate left / right spacing position.
Pin 35 and the steering arm 6 of the final case 14 provided facing the outer side are connected by a steering rod 7, and by the left and right movements of this hydraulic cylinder 3, the left and right front portions are connected via the steering rod 7. The wheels 1 are steering-linked.

The cylinder rotation stopping mechanism 8 includes the bracket 3
The guide rod 38 is integral with the front axle housing 2 via the guide rod 38 and the guide piece 39 is integral with the hydraulic cylinder 3. The piston rod 5 extends between the brackets 33 at the left and right ends of the front axle housing 2.
A guide rod 38 is provided in parallel with the guide rod 39, and a guide piece 39 projecting from the central portion of the hydraulic cylinder 3 is provided with a recess 40 that is constantly fitted to the guide rod 38. Hydraulic cylinder 3
This guide piece 39
Since the recess 40 is fitted into the guide rod 38 and slides, it is regulated even when the turning force acts, and the hydraulic cylinder 3 does not rotate about the piston rod 5 and performs accurate steering interlocking.

Incidentally, such a cylinder rotation stopping mechanism 8 is
It may be provided between the hydraulic cylinder 23 for steering the rear wheel 22 and the rear axle housing 21. 7 to 10, a point different from the above example is that the wheel base of the tractor vehicle body is changed in length by attaching and detaching the extension case 41. 7 and 8, the extension case 41 is removed to shorten the foil base, and in FIGS. 9 and 10, the extension case 41 is interposed to extend the foil base.

A gear case 42 extending rearward is provided at both left and right ends of the rear axle housing 21, and between the gear case 42 and a gear case 43 on which the final case 16 is rotatably mounted around the steering pin 37 axis. Further, the extension case 41 is interposed. These gear cases 42,
43 is a differential device 44 in the rear axle housing 21
From the left and right diff shafts 45 through the gear mechanism 46
And a transmission shaft 47, a bevel gear mechanism 48, etc.
Joining surfaces A and B in the vertical and longitudinal directions around the lateral transmission shaft 47
It can be joined and separated by. This joining and separation is done with bolts.

As shown in FIGS. 9 and 10, the extension case 41 has a joint surface a which can be joined to the joint surface A of the gear case 42 and a joint surface b which can be joined to the joint surface B of the gear case 43. It has a flat surface and is set to a predetermined length, and has a gear mechanism 49 inside, and the transmission shaft 47 and the input gear 50 boss portion are fitted and interlocked with the gear mechanism 49 on the input side. On the output side, the bevel gear 5 of the bevel gear mechanism 48
The output shaft 52 can be fitted and interlocked with the one boss portion and can be interposed between the both gear cases 42 and 43. As a result, the distance between the shafts 47 and 52 of the extension case 41 can be increased. Further, since the joint surfaces a and b of the extension case 41 are formed on the same plane, the tread does not change.

[Brief description of drawings]

FIG. 1 is a plan view of a front axle housing part and a side view of a part thereof.

FIG. 2 is a front view of a front axle housing and a rear axle housing portion.

FIG. 3 is a plan view thereof.

FIG. 4 is a sectional view of a front wheel steering hydraulic cylinder.

FIG. 5 is a sectional view of a rear wheel steering hydraulic cylinder.

FIG. 6 is a side view of the tractor.

FIG. 7 is a side view of a tractor showing another embodiment.

FIG. 8 is an enlarged development view of a part thereof.

FIG. 9 is a side view showing the operation of a part thereof.

FIG. 10 is an enlarged development view of a part thereof.

[Explanation of symbols]

 1 Wheel 2 Axle Housing 3 Hydraulic Cylinder 4 Fixed Piston 5 Piston Rod 6 Steering Arm 7 Steering Rod 8 Hydraulic Cylinder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masanori Imai No. 1 Hachikura, Tobe Town, Iyo-gun, Ehime Prefecture

Claims (1)

[Claims] 1. A piston rod (5) having a fixed piston (4) is provided in a hydraulic cylinder (3) along an axle housing (2) having steerable wheels (1) at left and right ends, and a hydraulic operation is performed on the piston rod (5). The hydraulic cylinder 3
And a steering rod 7 between the left and right steering arms 6 of the wheels 1.
A steering device for a tractor, which is connected to the axle housing 2 and a hydraulic cylinder 3 and is provided with a cylinder stopping mechanism 8 for stopping the rotation of the hydraulic cylinder 3 and interlocking with the steering.