JPS5845166Y2 - Agricultural tractor steering device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a steering device for an agricultural tractor.

Agricultural tractors can be operated either in a standing position or in a sitting position. When driving in a standing position, it is desirable that the steering wheel be vertical; when driving in a sitting position, the steering wheel should be vertical. It is desirable to tilt the steering wheel toward the front, and there is a demand for the steering wheel to have a tilt mechanism.

Conventionally, as a steering wheel tilt mechanism that does not use orbit roll, there is a mechanism that uses a bendable joint on the steering shaft, but if the joint is placed near the steering wheel, the height of the steering shaft/fle when tilted is Since the change in height is small, when the steering wheel is set vertically, the height of the steering wheel is low, making it difficult to drive in a standing position.

Therefore, it becomes necessary to provide the steering wheel shaft with a telescopic function, which complicates the structure.

In addition, if the joint is installed far away from the steering wheel and below, it will be possible to change the height position higher when the steering wheel is upright, but when tilting, the amount of movement of the steering wheel in the front and back direction will be large. Therefore, it requires a large amount of space.

Furthermore, there are steering wheels equipped with an orbit roll and a tilt mechanism.

In this case, the orbit roll main body rotates, and one end of the hydraulic pipe connected to the orbit roll also moves together.

Therefore, it is necessary to provide sufficient space for the hydraulic pipes to move so that excessive force due to twisting or bending is not applied to the hydraulic pipes.

This idea was created in view of the above points, and it is possible to increase the change in height when the steering wheel is turned from a reclined position to an upright position without providing a telescopic function to the steering wheel shaft. The object of the present invention is to provide a steering device for an agricultural tractor that can reduce the turning space of the steering wheel and the piping space of the hydraulic pipes, and protect the hydraulic pipes.

This invention coaxially connects an orbit roll to which a hydraulic pipe is connected by a rotation joint to a short holding part that holds the steering wheel, and sets the center of rotation of the holding part at a height near the orbit roll for steering the steering wheel. It is characterized by a raised wheel located at a position away from the axis of the wheel in front of the driver's seat.

In other words, the center of rotation of the holding part that holds the steering wheel is set at a position away from the axis of the steering wheel toward the front of the driver's seat, so even if the height of the center of rotation is located toward the steering wheel, The height change when tilting is increased to make it easier to drive in a standing position.
This eliminates the need for the steering wheel axis to have a telescoping function, reducing the space required for tilting.In this case, one end of the hydraulic pipe moves around the center of rotation of the holder along with the orbit roll. but,
The center of rotation is near the orbit roll, and the hydraulic pipe is connected to the rotating joint, so no excessive force is applied to the connection end, and there is no change in the loop due to tilt. It is designed to reduce space.

An embodiment of this invention will be explained based on the drawings.

Reference numeral 1 designates an agricultural tractor, and a column 5 serving as a holding portion for holding a steering wheel 4 is provided inside a dash board 3 provided on a driver's seat 2.

This column 5 is formed with a relatively short axial length,
Further, a support 7 is provided, the rotation center 6 of which is located at a position offset from the axis of the driver's seat 2 in front of the driver's seat 2.

In this embodiment, this support 7 is formed separately and is fixedly attached, but it may be formed integrally with the column 5.

An orbit roll 8 is attached to the support 7 so as to coincide with the axis of the column 5.

Four rotating joints 9 are attached to the sides of this orbit roll 8.

One of them is shown in FIG. 2. The rotary joint 9 has an eye bolt 11 screwed into the side surface of the orbit roll 8 through which a ring 10 is inserted, and the eye bolt 11 is rotated in the front and rear direction within a vertical plane. It consists of a boss 12 that is movably fitted.

The fitting peripheral surfaces of both are sealed by a sealing member 13.

Further, a washer 14 is passed through the outer end of the eye bolt 11, and a nut 15 is screwed into the washer 14 from the outside.
The boss 12 is prevented from being removed.

A pipe screw 17 fixed to one end of the hydraulic pipe 16 is connected to the outer periphery of these bosses 12.

These pipe screws 17 are connected to each port of a valve (not shown) inside the orbit roll 8 by an oil passage 18 passing through the center from the outer periphery of the eye bolt 11.

There are a total of four ports, the first is a port that is connected to the pump via the hydraulic pipe 16 (not shown), the second is a port that is connected to the tank via the hydraulic pipe 16, The third and fourth ports are connected via a hydraulic pipe 16 to a double-acting hydraulic cylinder that performs a steering action.

The hydraulic pipe 1 is located inside the dash board 3.
A presser 19 is attached to a part of the body, through which the holder 6 is slidably inserted.

In such a configuration, when driving in a seated position, the steering wheel 4 is operated by tilting as shown in FIG.

When driving in a standing position, operate the steering wheel 4 with the steering wheel 4 vertically as shown in FIG.

At this time, the rotation center 6 of the tilt is located at a position away from the axis of the steering wheel 4 toward the front of the driver's seat 2, so the height of the steering wheel 4 changes from the state of tilting toward you to the state of standing up. is big.

This allows the steering wheel to be placed high in the upright position, making it easier to drive in a standing position.

Such an effect can be obtained without providing a telescopic function to the shaft of the steering wheel 4, so the structure is simplified, and it can also be obtained without having to position the rotation center 6 far away from the steering wheel 4 and below. The space required for tilting is also small.

Furthermore, the boss 12 of the rotary joint 9 rotates relative to the eye bolt 11 during tilting.

In other words, the relative position between the boss 12 and one end of the hydraulic pipe 16 does not change, and no force is generated to change it.

As a result, the hydraulic pipe 16 does not cause any loop change and the presser tool 1
Move in a straight line between 9 and 9.

Therefore, the hydraulic pipe 16 can be protected, and
The piping space around the driver's seat 2 can be reduced.

Such a change in the length of the hydraulic pipe 16 between the orbit roll 8 and the holding tool 19 can be adjusted by bending the hydraulic pipe 16 in another free space of the agricultural tractor 1.

As mentioned above, this idea was developed by locating the center of rotation of the tilt at a position away from the axis of the steering wheel in front of the driver's seat, thereby increasing the height change of the steering wheel as it tilts, making it possible to maintain a standing posture. This type of action can be obtained without having a telescopic function on the steering wheel shaft, which simplifies the structure and requires the center of rotation to be located far away from the steering wheel and below. The space required for tilting can be reduced, and
The center of rotation is near the orbit roll, and
Because the hydraulic pipe is connected to a rotating joint installed on the orbit roll, it does not receive excessive force during tilting operations, and the loop change around the driver's seat due to tilting operations is extremely small, so the This has the advantage of being able to reduce the piping space.

[Brief explanation of the drawing]

The drawings show one embodiment of this invention; Fig. 1 is a partially cutaway and reduced side view showing the overall mechanism; Fig. 2 is an enlarged longitudinal sectional front view showing the structure of the rotary joint; 3
The figure is a longitudinal side view of a portion of the vehicle with the steering wheel tilted forward, and FIG. 4 is a longitudinal side view of a portion of the vehicle with the steering wheel upright. 2... Driver's seat, 4... Steering wheel 5... Column (holding part), 6-...
・Rotation center, 8...Orbit roll, 9...
...Rotating joint, 16...---Hydraulic pipe.

Claims (1)

[Scope of utility model registration request] An orbit roll to which a hydraulic pipe is connected by a rotation joint is coaxially connected to a short holding part that holds the steering wheel, and the center of rotation of the holding part is aligned with the axis of the steering wheel at a height near the orbit roll. A steering device for an agricultural tractor, characterized in that the steering device is positioned in front of a driver's seat.