JPH03200484A - Riding-type working vehicle - Google Patents

Abstract

PURPOSE:To facilitate driving in a riding-type working vehicle with a mower connected to the body front part thereof by providing display devices for indicating the steering direction and steering angle of the body in the state of being linked with rear wheels so as to be operated automatically in linkage with the steering oscillation of the rear wheels. CONSTITUTION:The turning of a steering wheel 6 is transmitted to rear wheels 2 through a pinion gear 26, a sector gear 21, a pitman arm 11, a first drag link 31, a reverse link 32 and a second drag link 33. The display boards 12 of steering display devices 8 fitted at the bilateral front ends of a body 3 are fitted rotatably around fulcrums 16 as well as form a parallel quadruple link by a link rod 30, and the link rod 30 is connected to the operating arm 11b of the pitman arm 11 so as to rotate the display boards 12 according to the steering of the rear wheels 2. With this constitution, the operation of the steering wheel can be facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a riding-type working vehicle configured to connect a working device such as a mower 7 to the front portion of the vehicle body.

[Conventional technology]

In riding work vehicles with rear wheel steering and work equipment connected to the front of the vehicle, the front wheels are non-steering, so the direction of travel of the vehicle cannot be determined by the orientation of the front wheels, making it difficult to move the vehicle. It was only when I saw it that I was able to discern its direction of travel.

[Problem to be solved by the invention]

In this way, the steering direction of a rear-wheel steering type work vehicle cannot be recognized until it is moving forward, and because the movement of the work equipment located in front of it is small, the steering direction may be misjudged and oversteering may occur. In particular, inexperienced drivers were prone to colliding with obstacles with the working equipment at the front of the vehicle body.

SUMMARY OF THE INVENTION An object of the present invention is to facilitate the operation of a rear wheel steering type riding work vehicle and to solve the above-mentioned problems.

[Means to solve the problem]

The present invention provides a steering display device for displaying the steering direction and steering angle of the vehicle body to the driver in the riding-type work vehicle, in a state where the steering display device is automatically activated in accordance with the steering swing of the rear wheels. It is characterized in that it is provided in conjunction with the rear wheel.

[For production]

With the above configuration, the driver can steer the vehicle while visually checking the steering direction and steering angle of the vehicle using the steering display device.

〔Effect of the invention〕

Therefore, according to the present invention, the control handle can be easily operated, and even an unskilled driver can easily operate the vehicle, thereby increasing work efficiency.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, an embodiment in which the present invention is applied to a riding lawn mower will be described based on the drawings.

As shown in Fig. 4, a steering handle (6
), a driver's seat (5) and an engine (9) are mounted, and a mower (4), which is an example of a work device that can be raised and lowered by a hydraulic cylinder (17), is attached to the front of the vehicle body (3), making it a riding type vehicle. The lawn mower is configured.

The front wheels (1) and the rear wheels (2) are driven by a hydrostatic continuously variable transmission (22), and the hydraulic circuit for shifting is shown in FIG. As shown, charge pump (19
) A control valve (18) for the hydraulic cylinder (17>) configured as a single-acting type is interposed in the middle of the charge oil passage (25) that receives pressure oil supply from the charge oil passage (25). A relief valve (
20) is interposed, and this relief valve (20) is
As shown in FIG. 3, a small diameter hole (24a) is formed in the poppet (24), so that even if the control valve (18) is in the cylinder raised position, a suitable small amount of oil can be passed through the bypass path.
26) to the charge oil passage (25) on the lower side of the control valve.
The charge oil is configured to flow to the transmission circuit, so that charge oil is constantly supplied to the transmission circuit.

Next, the steering structure of the rear wheels (2) will be explained.

As shown in FIG. 1, a fan-shaped gear (21
> is connected to the pitman arm (11), and this pitman arm (11) and the rear wheel steering link mechanism (
The knuckle arm (13) of 15) is interlocked and connected via a first drag link (31), a reversing link (32), and a second drag link (33).

Further, the pitman arm (11) and steering display devices (8) disposed on the left and right sides of the front end of the vehicle body (3) are mechanically linked as follows.

The steering display device (8) has a display plate (12) with an arrow mark (a) on the top surface attached to the vehicle body (3) so as to be rotatable around a fulcrum (16). Display board (1
2) and (12) in the form of a parallel four-speed link, the middle part of the linking rod (30) is linked with an elongated hole pin to the operation arm (lla) extending forward from the pitman arm (11), and the rear wheel (2) ) The display board (12) is rotated to the left or right so that the arrow mark (a) indicates the vehicle direction, and this can be seen visually from the driver's seat (5).

Further, a headlamp (7) is attached to the front surface of the display board (12), and is configured to illuminate the front in the direction of the vehicle.

The steering display device (8) can be modified in various ways, for example, as shown in FIG.
It may be possible to rotate a circular display board (12) marked with . It is also possible to electrically rotate the display board (8) based on the detected amount of steering of the rear wheels (2), and furthermore, the display mark (a) itself can be displayed in the direction of the arrow using an electric display. It is also conceivable to configure it so that it changes. Further, the steering display device (8) may be provided at a visible location at the center of the front end of the vehicle body (3).

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of drawings]

The drawings show an embodiment of the riding type work vehicle according to the present invention, and the first embodiment
The figure is a plan view showing the interlocking mechanism between the steering display device and the rear wheels, Figure 2 is a hydraulic circuit diagram, Figure 3 is a sectional view of the relief valve, and Figure 4 is a sectional view of the relief valve.
The figure is an overall side view of the riding lawn mower, and FIG. 5 is a plan view showing another embodiment of the steering display device. (1)...Front wheels, (2)...Rear wheels, (3)...Vehicle body, (4)...Working equipment, (8) ...Display device.

Claims (1)

[Claims] A riding type work vehicle in which a front wheel (1) is mounted so as not to be steerable and a rear wheel (2) is mounted so as to be freely steerable, and a working device (4) is connected to the front part of a vehicle body (3). , car body (
The steering display device (8) for displaying the steering direction and steering angle of (3) to the driver is automatically activated in accordance with the steering swing of the rear wheels (2). A riding work vehicle that is connected to 2).