JPS61215108A - Wheel supporting structure of four-wheel working vehicle - Google Patents

Abstract

PURPOSE:To improve safety of a four-wheel working vehicle for farming use, etc. by constituting its wheel supporting structure in such a way that oil chambers for a laterally supporting mechanism for vertically movable wheels are communicated with an oil route which is cut off when oil pressure is under a specified value and opened when oil pressure is above the value. CONSTITUTION:While rear wheels are made vertically immovable, front wheels 1 are constituted so as to be vertically movable, with a 4-serial linkage-type suspension mechanism 16 installed between them and the car body. And upper oil chambers (a), (a) of hydraulic cylinders 17, 17 supporting right and left link age mechanisms 16, 16 are communicated with oil passages 19, 19 equipped with relief valves 20, 20, which form a pair of reciprocal relief valves opened with oil pressure more than a specified value. Therefore, if oil pressure in the oil chamber a is less than the specified value, shift of oil pressure does not occur, with contrary vertical moves prevented. Based on such a constitution, the vehicle can run on unprepared or slanting grounds safely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a wheel support structure for a double-wheel working vehicle for agricultural or earthwork purposes that travels over uneven or sloped fields or rough terrain.

[Conventional technology]

As the wheel support structure of the work vehicle, a pair of left and right wheels are provided at the front and rear of the vehicle body, one of the front and rear wheels is configured to be immovable up and down, and the other wheel is configured to be able to move up and down, and the left and right movable wheels are configured to be able to move up and down. [Problems to be Solved by the Invention] The above-mentioned wheel support structure is constructed so as to allow and prevent reverse vertical movement of the movable wheel by communicating and blocking communication using a pair of oil chamber valves that support the ground load of the vehicle. The vehicle is configured so that the movable wheels follow the unevenness of the ground and move up and down in opposite directions, allowing the vehicle to run as if it were in contact with the ground. When the vehicle was tilted to the side and the vehicle was in a stable state, a valve was locked to prevent the movable wheels from moving up and down, thereby preventing the vehicle from tilting further.

For this reason, it is necessary to switch the valve mechanism 'kf7J' when driving on normal rough terrain and when driving on slope. If you forget to perform this switching operation, especially when changing from driving on rough terrain to driving on slope, there is a risk of a fall accident. Ta.

This invention provides a wheel support structure that enables highly safe driving by automatically operating the pressure valve so that the movable wheel follows unevenness when driving on rough terrain, and prevents vertical movement of the wheel when driving on slope. This is what we intended to provide.

[Means for solving problems]

In order to achieve the above object, in the present invention, communication between the two oil chambers is cut off when the internal pressure of one of the pair of oil chambers supporting the ground load of the left and right movable wheels is lower than a set value, and when the internal pressure is lower than the set value, The valve was configured to communicate between the two oil chambers by detecting pressure.

[For production]

According to the above configuration, basically on flat ground, the ground loads acting on the left and right movable wheels are approximately equal, the internal pressure of each oil chamber is lower than the set value, and the movable wheels are fixed. Then, when the vehicle enters rough terrain with large irregularities and a large ground load is applied to one side of the movable wheels, the left and right movable wheels become capable of vertically moving oppositely, and both movable wheels come into contact with the ground.

Furthermore, when traveling along a slope, the internal pressure increases on one side of both oil chambers, but it does not rise to a value that would switch the valve mechanism, and the movable wheel is fixed.

〔Effect of the invention〕

Therefore, according to the present invention, a wheel support condition suitable for running on rough terrain and running on slope is automatically provided without performing a special valve switching operation, and on rough terrain, the wheel support state suitable for running on rough terrain is achieved by V-axis grounding. Moreover, it is now possible to drive safely on slopes by preventing the wheels from moving up and down.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

Figure 3 shows a sugar cane harvester, which is an example of a double-wheel working vehicle, with steerable front wheels ill and ill and non-steerable drive rear wheels +21 and 121'! I-Car body with (3
) is equipped with a prime mover room (4), a driver's cab (51 seats, and a top cutter 16 at the front of the car body), and a screw-set culm lifting device (7) that can be freely adjusted up and down. In addition, between the left and right wheels on the lower abdomen of the vehicle body, there are provided a guide roll (8) for tilting the planted stem culm forward, a disc-shaped cutter (9) for cutting the base of the introduced stem culm, and a cut stem culm. A pair of upper and lower gripping rolls f that pulls the stock backward from the stock end side.
lO) @ flol A group of defoliating rollers (Ill...) that rotate at high speed by acting on the stem culms sent rearward and upwards are installed, and furthermore, at the rear of the vehicle body, a group of defoliating rollers (Ill...) are installed that move the defoliated stem culms up and down. (conveyor bell that supports the vehicle and transports it backwards and upwards) Q2
1, fJ21. At the end of the conveyance, there are disposed a discharge roller A31° that applies a discharging force to the stem culm, and a blower I that blows off leaves entangled and attached to the stem culm.

Additionally, a trailer is connected to the rear of the vehicle to collect the released stalks.

The rear wheels +2+ and +21 are provided so as not to be able to move up and down, whereas the front wheels 11+ and fi+ are provided with the second
As shown in the figure, each link mechanism Q61 is supported on the vehicle body (3) via a link type suspension link mechanism Q61' (i7) so as to be vertically movable.
, uυ is the hydraulic cylinder Q71. (Supported by lη.

FIG. 1 shows the hydraulic circuit structure for the hydraulic cylinders 071 and (lη).

- The hydraulic cylinder aη, Q71 is connected to a manually operated control valve (I8), and the hydraulic cylinder aη, Q71 is synchronously
The height of the cutter (9) above the ground can be adjusted by hydraulically raising and lowering the front wheels 111, 111.

In addition, the upper oil chambers of both hydraulic cylinders (1η, +171, the oil chambers (a+, 161) that support the ground load of the front vehicle N1111, Ill, the oil passages 01, Q
*, and a pair of forward and reverse relief twos, which open at a pressure higher than the set value, are incorporated into this oil passage -, (191), so that the internal pressure of both oil chambers (a) and lal reaches the set value. In a lower range, the reverse vertical movement of both vehicles N1 (..., (1) is prevented, and when the internal pressure of either oil chamber (al) rises above the set value, both oil chambers (al, lal) are communicated and the vehicle (It is configured to allow vertical and vertical movements of 11° + 11 degrees.

The set pressure at which the relief valve 201 opens is the internal pressure Vr- of the oil chamber (a+) with respect to the front wheel load on the slope side when the vehicle body (3) is rolled over or the vehicle body (3) is tilted at a slightly smaller angle. It is set.

Therefore, basically, even if the vehicle body (3) tilts sideways, the left and right front wheels (ill, 11+) remain in a fixed state, and when driving on rough terrain with large irregularities, if a large ground load is applied to only one front wheel (i.e., The partial pressure cylinders aη, aη are communicated, and the left and right front wheels 111, 111 move up and down oppositely to follow the unevenness.

[Another example]

(2) In the above embodiment, the left and right wheels 111 and 111t'' are configured to be able to move up and down, but it can also be applied to a device that can simply move up and down.

■ In the case of a device that simply moves up and down in a contradictory manner, as shown in FIG.
Supported at both ends of the axle frame U around which the balance swings,
A single hydraulic cylinder α between this axle frame and the car body
It is also possible to implement a structure in which the upper and lower oil chambers Ta) of this hydraulic cylinder +171 are communicated via the relief valve 4).

■ As shown in Figure 5, the front wheels 1tl, ltl
l (It is configured to be vertically movable via transmission coos w and bi that can freely swing up and down, and the rear wheels +21 and +21 are used as steering wheels, It may be configured to operate with the circuit shown in FIG.

■ Front wheels [11, 111 fully fixed, rear wheels 121,
+21 can also be implemented in a form that moves up and down.

[Brief explanation of drawings]

The drawings show an embodiment of the wheel support structure for a double wheel working vehicle according to the present invention, in which FIG. 1 is a hydraulic circuit diagram, FIG. 2 is a front view of the wheel supporting structure, and FIG. 8 is an overall side view of the working vehicle. FIG. 4 is a schematic front view showing another embodiment of the wheel support structure, and FIG. 6 is a side view of a working vehicle equipped with a different wheel support structure. 111...Movable side wheel, (2)...Identification side wheel, 4...Valve, +81...Oil chamber.

Claims (1)

[Claims] A pair of wheels (1), (1), (2) on the left and right at the front and rear of the vehicle body,
(2), one of the front and rear wheels (2), (2) is configured to be immovable up and down, the other wheel (1), (1) is configured to be movable up and down, and the left and right movable wheels (1), (
A pair of oil chambers (a), (a) that support the ground load of 1) are communicated and disconnected by valves (20), (20) to prevent the reverse vertical movement of the movable wheels (1), (1). The wheel support structure of a four-wheeled work vehicle is configured to allow and block the oil chambers (a), (a) in a range where the internal pressure of one of the oil chambers (a), (a) is lower than a set value. The wheel support of a four-wheeled working vehicle is configured such that the valves (20), (20) are configured to cut off the communication between the oil chambers (20) and (20) and communicate the two oil chambers (a), (a) by detecting a pressure equal to or higher than the set value. structure.