JPS60128077A - Power steering unit in tractor - Google Patents

Abstract

PURPOSE:To make it possible to compactly mount a power steering unit laid crosswise in a front frame, being kept away from an engine section, by laying a steering control shaft extending from one end of the unit at a right angle or a substantially right angle with respect to a valve control shaft. CONSTITUTION:Front wheels 8 are directly associated and coupled to a pitman arm 13 in an integral type steering unit 12 which is mounted crosswise on the front section of a chassis frame, being kept away from an engine, through a knuckle arm 10 and a tie rod 11, and a steering wheel 6 is associated and coupled to a steering control shaft 15 which is projected upward from the right end of the unit 12, through a shaft transmission mechanism 14. The pitman arm 13 of the steering unit 12 is driven and swung under hydraulic pressure by operating the steering wheel 6, and therefore, the steering control of the front wheels 8 is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an integral type power steering device installed in a tractor.

Generally, the integral type 7-hour in tractors,
- The steering device is installed in an upright position at the lower end of the steering handle shaft on which the power steering unit is installed, so that the pulp operation shaft of the unit and the handle shaft are concentric, and the drive type pitman arm provided on the unit A structure is adopted in which the knuckle arm of the front steering axle is linked by a drag link, but the drag link, which is subject to strong push and pull, is bent in the middle to avoid contact with other devices. In some models, the durability of the drag link against buckling deformation was a problem.

Therefore, in order to omit this drag link, as shown in Fig.
Connect the drive type pitman arm to the middle of the tie rond slant, and connect the nine pulp operating shaft protruding from one end of the unit@Hani and the steering handle shaft (not shown) with a universal joint.
A structure was devised in which the shaft transmission 11η includes the following.

However, in this case, due to the permissible range of the refraction angle of the universal joint interposed in the shaft transmission It became necessary to transform the foundation itself to install the unit, which required expensive modifications to the tractor itself.

The present invention focuses on this point, and allows the power steering unit to be compactly installed near the steering wheels without major modification of the tractor itself by relatively simple modification of the power steering unit.

The present invention is characterized in that an integral type power steering unit is mounted horizontally on a curved part of the fuselage, the pitman arm and the knuckle arms of the left and right front wheels are interlocked and connected with a rond, and the pulp operation shaft of the power steering unit is The steering operation shaft interlocked with a bevel gear extends from one end of the unit at right angles or almost at right angles to the pulp operation shaft, and its effects are as follows.

In other words, since the steering operation shaft extends from the end of the unit at right angles or almost at right angles to the pulp operation axis, it is possible to rotate the steering wheel shaft to the rear steering handle shaft.
The JIa structure and the unit can be installed almost perpendicularly, so the unit can be horizontally mounted in a compact manner at the front of the machine, avoiding the driving part. As a result, major modifications to the tractor machine side are not required. This made it possible to inexpensively install an integral type power steering device that omitted the drag link.

Next, embodiments of the present invention will be described based on the drawings.

As shown in Figure 1, the engine (1) is located at the front of the aircraft, and the clutch link (2) is located at the rear of the output side of this engine
) is installed, and a mission booth (
3), and above the mission booth (3) there is a lift arm (4) to which work equipment can be attached, further above is a pilot seat (5), and in front of the pilot seat (5) is a steering handle (5). 6) is provided. Further, a steering front axle (8) is supported on the front part of the body frame (7), and a rear wheel (9) is supported on the mission booth (3) so as to be drivable, so that an agricultural tractor is filmed.

As shown in FIGS. 1 and 2, the front wheels 181,
+81 I/i Knuck Lure A flol, (i
It is interlocked and connected to the pitman arm of the integral type power steering unit, which is suspended horizontally at the front of the fuselage frame (7) through the ll and tie 07 (■), avoiding the driving part. , the steering handle (6) is connected to the shaft rolling machine 1ll (the unit via the shaft).
(Steering operation shaft protruding upward from the right end of 121 (
It is linked to lf9. Then, by rotating the steering handle (6), the pitman arm ll:l of the unit O4 is hydraulically driven and swayed, and the front wheels (81, (8)) are steered by the power steering system. is being created.

FIG. 8 shows the steering operation shaft (16) in an extended state in which it has been rotated 90 degrees rearward. Based on FIG. 8 and FIG. 4, the power steering unit of the present invention is (The operation of 1'4 will be explained in detail. When the steering operation shaft 05) is rotated, the bevel gear -〇〇#i connected to it by a spline is engaged with the bevel gear, and the bearing is attached to the unit (12). (171, (
The right end of the bevel gear (11) is slidably fitted into a spline hole (18 m) drilled in the direction of force (Pi). The pulp operating shaft H is rotated, and further,
In the center of this pulp operation shaft (1c4), a cylindrical spool (c) constituting the hydraulically controlled pulp (Vl) is fitted inside the pulp booth part 3η, and is fitted externally on the pulp operation shaft (19). 1, and the pulp operating shaft (III) is inscribed in the unit 0'4 through a ball screw 4 in the left throat thereof, and is provided with the shaft center (a piston member slidable in the Pl direction). When the pulp operation shaft (1) is rotated, it is moved in the axial direction by the reaction force from the pole screw (4). Chamber (24a).

(94b) is formed, and an oil passage (85
m), (grtb) is the groove formed in the sprue through the bulb goose (2 girders (gQa), (90b)
These grooves 5 (2) are connected to each other as shown in FIG.
0a).

(2ob) n Furthermore, the pump boat side gutter portion and the drain port side gutter portion formed on the bulk coat 21).

Since each of the parts is placed in short-circuit communication, the flow of hydraulic oil and the curved oil chamber (1!4m),
The piston member (c) is maintained in a neutral state due to the pressure oil balance in (24b), so when the pulp operating shaft wheel is rotated, the piston member (c) does not move immediately, but first the pulp operating shaft 9 is moved in the direction of the axis (PI force).

Until now, operations have only been performed manually. Also, for example, assuming that the pulp operating shaft wheel is moved to the right (4), the spools disposed on the pulp operating shaft are both moved to the right, and the groove portion (2) of the spool 4 is moved to the right.
ob) communicates with the groove S on the pump boat side with a wider flow area than in the neutral state, and also connects with the groove S of the spool (90 m
) is the groove part on the drain boat side @η, which communicates with the foundation with a wider channel area than in the neutral state, and each groove part (Rob)
.

Oil chamber (84m) connected to (20a), C24b)
The pressure oil in the left oil chamber (24a) is the same as that in the right oil chamber (24a).
24b), and the piston member (231
will be moved to the right. As a result, the pinion gear mesh engaged with the rack gear (b) formed on the piston member is rotated, and the pitman arm I, which is coaxial with the pinion gear, is swung to the left. When the piston member (c) is moved to the right, the pulp operating shaft (IC4) is also feedback-moved to the right, and when the spool reaches the neutral position, the respective oil chambers (24a) are moved.

The hydraulic pressure (84b) is balanced and the movement of the end of the piston member is stopped.

As described above, the piston member (c) is actuated instantaneously in response to the rotation of the steering operation shaft 9, and as a result, the steering operation shaft (16) is rotated. Pitman Arm 9 was driven and moved as the
When the rotation stops, the arm stops.

[Brief explanation of drawings]

The drawings show an embodiment of the power steering device for a tractor according to the present invention, and FIG. 1 is an overall side view, FIG. 2 is a schematic plan view of the front part of the machine, and FIG. 8 is a cross-sectional plan view and a side view of the power steering device. FIG. 4 is a sectional view of the main part of the power steering device, and FIG. 5 is a schematic plan view of the front part of the conventional fuselage. (8)...Front wheel, frame...knuckle arm, '('')...rod, 0'4...
・Power steering unit, -... Pitman arm, α... Steering operation shaft, O
Groan... Valve operation shaft. Agent Patent Attorney Osamu Kitamura Tokukaisho GO-128077 (4)

Claims (1)

[Claims] Integral type power steering unit (I
2) is mounted horizontally on the front of the aircraft, and the pitman arm and left and right front wheels (a), (knuckle arm 110 of 81)
. (10) are interlocked and connected with the ronds (1) and (11), and the steering operation shaft C15), which is interlocked with the bevel gear to the pulp operation shaft O1 of the front C power steering unit (I2), is connected from the unit end to the pulp operation shaft -. A tractor power steering device that extends at right angles or nearly right angles to the vehicle.