JPS6387378A - Steering gear for vehicle - Google Patents

Abstract

PURPOSE:To reduce the abrasion of a tire by allowing the front and rear wheels to be turned in the steering direction when the front and rear bodies are bent, thus permitting a small radius turn, in a car in which a front body having front wheels and a rear body having rear wheels are connected in bendable ways. CONSTITUTION:In a bent trunk type tractor, front wheels 20 are axially supported in rotatable ways around a king pin 18 at the right and left edges of a front axle 15 supported onto a front body 10. A rear body 22 is connected in bendable ways around a longitudinal shaft 26 in the rear part of the front body 10, and the rear body 22 has rear wheels 25 which are turntable around a king pin 43. In this case, a knuckle arm 21 for turning a front wheel 50 around the king pin 18 is pivotally supported at the right and left edges of a rear bracket 35 in the front part of the rear body 22 through a drag link 38 for front wheels. Further, a knuckle arm 44 for turning the rear wheels 25 around a king pin 43 is pivotally supported at the right and left edges of a front bracket 34 in the rear part of the front body 10 through a drag link 45 for rear wheels.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a steering device for a vehicle, which steers both front and rear wheels.

(Prior Art) Conventional steering devices for two-axle, four-wheel vehicles such as tractors are shown in FIGS. 4 and 5.

Figure 4 shows a vehicle in which the front wheel 2 of the front wheels 2 and rear wheels 3 provided on the vehicle body 1 is rotatable around a kingpin, and the front wheel 2 is steered by operating the steering wheel to turn around the turning center 0. be.

Fig. 5 shows a so-called folding body type in which the front body 4 and the rear body 5 are connected so as to be bendable around the vertical axis 6, and when the steering wheel is operated, the car bodies 4 and 5 are bent around the vertical axis 6 and the turning center O is It rotates around.

(Problem to be solved by the invention) However, in both cases of Figs. 4 and 5, the front wheel 2
Since there are limits to the turning angle of the vehicle and the bending angle of the vehicle bodies 4 and 5, it is not possible to reduce the turning radius, and therefore it is not possible to prevent the tires from slipping during sharp turns, resulting in significant wear and tear on the tires. There is a drawback.

An object of the present invention is to solve these problems by rotating both the front wheels and the rear wheels in a so-called folded-body configuration.

(Means for Solving the Problems) The technical means taken by the present invention to achieve the above-mentioned object is to connect a front vehicle body having front wheels and a rear vehicle body having rear wheels so as to be bendable around a vertical axis. In a vehicle in which the front and rear body parts are bent in the steering direction in conjunction with steering wheel operation, each of the front wheels 20 and rear wheels 25 is attached to a kingpin of 18°4.
The knuckle arm 21.44, which rotates the front wheel 20 and rear wheel 25, respectively, and the front/rear vehicle body 22 are configured to be rotatable in three directions, and when the front/rear vehicle body 10.22 is bent, the front wheel 20 and the rear wheel 25 are connected via drag links 38 and 45 so as to rotate in the operating direction.

(Function) When the handle 30 is operated, for example, to the left, the pair of left and right steering cylinders 37 expand and contract in opposite directions, so that the third
As shown in the figure, the front body 10 is bent proportionally to the left about the longitudinal axis 36 with respect to the rear body 22 .

When the front and rear vehicle bodies 10.22 bend, the left kingpin 18 of the front wheel 20 approaches the rear vehicle body 22 side, and the right kingpin 1B moves away from the rear vehicle body 22, so that the knuckle arms 21 of each kingpin 18 of the front wheel 20 and the rear bracket 35 are connected by the drag link 38, the left knuckle arm 21 is pushed forward around the king pin 18, and the right knuckle arm 21
On the contrary, the left and right front wheels 20 rotate in the steering direction around the king pin 18.

10,000, also on the rear wheel 25 side, the knuckle arm 44 attached to the upper end of the king pin 43 is rotated in opposite left and right directions,
Since this knuckle arm 44 and the front bracket 34 are connected by a drag link 45, the right knuckle arm 44 of the rear wheel 25 is retracted toward the front vehicle body 10,
The left knuckle arm 44 is pushed in the opposite direction, and the left and right rear wheels 25 rotate around the king pin 43 in the steering direction.

Therefore, the tractor can make sharp turns in a small radius around the turning center 0, and side lips are also reduced.

(Example) An example of the present invention will be described in detail with reference to FIGS. 1 to 3.

The figure shows a foldable body type tractor, and a front vehicle body 10 is provided with an engine 11 and a front transmission case 12 to constitute the vehicle body.

13 is a radiator, and 14 is a bonnet, which is attached to the front vehicle body 10 so as to cover the engine 11, the radiator 13, etc.

15 is the front axle, center axle 16, front axle bracket 1
It is supported by the front vehicle body 10 via 7.

A king pin 18 and a hub axle 19 are installed at both left and right ends of the front axle 15.
A front wheel 20 is attached via the front wheel 20, and the front wheel 20 is rotatable around the king pin 20.

Knuckle arms 21 are fixed to the upper end of the king pin 20, and each knuckle arm 21 projects inwardly and forwardly.

The knuckle arm 21 rotates the front wheel 20 around the king pin 18, and is positioned approximately 15 to 25 degrees forward of the front axle 15 in plan view so that the turning angle of the inner front wheel 20 is large when turning. is inclined to.

Reference numeral 22 denotes a rear vehicle body, which includes a rear transmission case 23 and the like, and a rear wheel 25 is attached to both sides of the rear body via a rear axle case 24, a rear axle 24A, etc.

A transmission case 46 with a built-in bevel gear transmission mechanism is attached to both left and right ends of the rear axle case 24.
6 is rotatable around the king pin 43, and the hub shaft on the rotation side is connected to the rear wheel 25, where the rear wheel 25 is rotatable around the king pin 43.

The king pin 43 is substantially a bevel gear shaft, and a knuckle arm 44 for rotating the transmission case 46, that is, the rear wheel 25, is attached around this pin.

26 is a rear wheel fender, 27 is a floor cover, and 28 is a step for getting on and off.

Further, 29 is a driver's seat, and 30 is a steering wheel, which is attached to the instrument panel section 31.

The front vehicle body 10 and the rear vehicle body 22 are arranged front and rear, and a pair of upper and lower front and rear plaques (34.35) are attached to opposing end surfaces of each of the vehicle bodies 10.22 via mounting plates 32.33,
A vertical shaft 36 is inserted therethrough, and the shaft 36 is pivotably connected to the shaft 36 so as to be bendable around the vertical shaft 36.

At both left and right ends of the rear placket 35, the rond side of the steering cylinder 37 and the rear end side of the front wheel drag link 38 are connected to pins 39.
40, the front end sides of the drag links 38 are pivotally connected to the front wheel knuckle arms 21, and the length of the drag links 38 is freely adjustable by a turnbuckle tube 42.

The steering cylinder 37 is connected to brackets 41 protruding from both sides of the front vehicle body 10, and is controlled via a steering control valve device (not shown) linked to the handlebar 30. When the steering wheel 30 is operated, the left and right steering cylinders 37 operate in opposite directions, and the front body 10 is moved around the vertical axis 36 relative to the rear body 22 in the direction in which the steering wheel is operated, that is, in proportion to the steering direction. It is made to refract.

Each front end of a rear wheel drag link 45 is pivotally connected to the front bracket 34 by a pin 47.
5 are pivotally connected to a rear wheel knuckle arm 44.

Furthermore, the drag link 45 is also connected to the turnbuckle tube 4.
It has 5^ and its length can be adjusted freely.

Therefore, the front body 10 is aligned with the longitudinal axis 36 relative to the rear body 22.
When bent around, the front wheel knuckle arm 21 and the rear vehicle body 22 are connected via the drag link 38, and the rear wheel knuckle arm 44 and the front vehicle body 10 are connected via the drag link 45. In the example shown in FIG. Both the front wheels 20 and the rear wheels 25 are rotated in the same direction around the respective king pins 18°43 in conjunction with the bending of the vehicle body.

In addition, numeral 48 has a travel transmission shaft, and 49 has a joint at a location that coincides with the vertical axis 36 of the PTO transmission shaft.

(Effects of the Invention) According to the present invention, both the front wheels and the rear wheels rotate in the steering direction when the front and rear vehicle bodies are bent, so that combined with the bending of the vehicle body, it is possible to make a sharp turn in a small radius. , less wear and tear on tires due to side slips.

In particular, when only the front wheels are turned around the king pin, the turning center is O' in Figure 3, but not only the front wheels but also the rear wheels are turning, so the turning center will shift from 0'' to O. Therefore, the turning radius can be made smaller and smaller.

In addition, since the knuckle arm is connected to the front and rear body sides, the structure is simple and can be implemented at low cost.
The shimmy phenomenon that occurs when driving can also be reduced.

[Brief explanation of the drawing]

The drawings show the present invention and a conventional example; Fig. 1 is a plan view of the present invention, Fig. 2 is a side view, Fig. 3 is an explanatory diagram of the same operation, and Figs. 4 and 5 are explanatory diagrams of the conventional example. be. 10...Front body, 18.43...King pin, 2
0... Front wheel, 21, 44... Knuckle arm, 22
... Rear body, 25 ... Rear wheel, 30 ... Handle, 36 ... Vertical axis, 37 ... Steering cylinder, 38, 4
5...Drag link.

Claims (1)

[Claims] (1) A vehicle in which a front body with front wheels and a rear body with rear wheels are connected so as to be bendable around a vertical axis, so that the front and rear bodies bend in the steering direction in conjunction with steering wheel operation. At this time, the front wheels 20 and rear wheels 25 are connected to king pins 18 and 4, respectively.
The knuckle arms 21 and 44, which rotate the front wheels 20 and the rear wheels 25, respectively, and the front and rear vehicle bodies 22 are configured to be rotatable in three directions. 25 are connected to each other via drag links 38 and 45 so as to rotate in the operating direction.