JPH10157998A - Three-wheel industrial vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent dislocation and side skid at the time of inclining by forming parts, brought into contact with the ground of a vehicle in case of a body being inclined sideways at a maximum allowable angle, to be large in frictional resistance. SOLUTION: In case of a vehicle traveling on the ground surface inclined downward to the left side or stopping on this ground surface, when a body is inclined to the left side at a maximum allowable angle, a right side drive wheel 2 is separated from the round surface, and a rubber sheet 5 stuck to the lower face of a counterweight 3 is pressed to the ground surface, so that the vehicle is grounded at three points of a left side drive wheel 2, a rear steering wheel 4 and the face of the rubber sheet 5. The vehicle therefore stays on even on the inclined face of 30 deg. or more without dislocation so as to ensure stability matching a four-wheel industrial vehicle. The inclination of the vehicle to the ground surface can be reduced by providing the rubber sheets 5 in such a way as to be protruded downward from the bottom face of the vehicle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forklift having, for example, a pair of left and right front wheels, only one rear wheel at the center, a cargo handling device at the front, and a counterweight at the rear. It relates to a representative three-wheeled industrial vehicle.

[0002]

2. Description of the Related Art In the above-described three-wheeled industrial vehicle, one of the front wheels is easily lifted when the vehicle is stopped on a ground inclined left and right, while traveling on the inclined ground, or when turning quickly even on a flat ground. Therefore, the maximum tilt angle is allowed in the vehicle body until the lower corner of the counterweight, which is opposite to the raised front wheel, comes into contact with the ground. Therefore, conventionally, a portion of the counterweight that comes into contact with the ground is provided with pressure resistance to increase the supporting strength, and in consideration of preventing deformation and increasing the inclination angle further, the lower corner portion of the counterweight is smooth without projections. It had a metal surface. In the present invention, the ground does not need to have the ground exposed, such as a road surface if a road, or a floor if indoors.
The surface on which the vehicle runs.

[0003]

In a tilt test in which a three-wheeled vehicle is placed on a surface plate and the surface plate is slowly tilted to test the limit of stability, when the vehicle is tilted to the limit as illustrated in FIG. Are three wheels 2, 2 ', 4 as shown in (a).
From the state in which both are grounded to the surface plate 8, the wheel 2 ′ on one side shown by a solid line in FIG.
The other bottom surface P is in contact with the surface plate 8 and is inclined at the maximum allowable angle. In this state, the back surface of the counterweight that is in contact with the ground is a solid and smooth surface, and that surface is in contact with the hard surface of the surface plate, and the weight is applied diagonally from above. As indicated by the dotted line, the three-wheeled industrial vehicle starts sliding downward. Therefore, when the vehicle is stopped on an inclined surface exceeding the limit, there is a possibility that a positional shift or a change in posture may occur unintentionally, or the vehicle may skid while traveling, impairing the driving feeling.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a three-wheeled industrial vehicle having excellent stability. The structure of the three-wheeled industrial vehicle is such that when the vehicle body is tilted to the side at the maximum allowable angle, the portion which comes into contact with the ground of the vehicle. Is formed with a large frictional resistance. The portion of the vehicle that contacts the ground may be a counterweight, and the portion that contacts the ground may be formed by a contact member having a large frictional resistance, or the portion that also contacts the ground may be formed from the bottom of the vehicle. The contact member may be made of a rubber sheet and project downward. When the lower left and right corners of the vehicle are chamfered, the chamfered portion is newly formed as a portion that comes into contact with the ground, and the portion is formed with a large frictional resistance. It is desirable that the surface of the weight that comes into contact with the ground be formed as a surface having a high frictional resistance.

[0005]

[Function] Even if the vehicle is stopped in a state where the vehicle body is inclined on an inclined surface, the vehicle does not slip on the ground due to high frictional resistance and does not shift in position, and even if the vehicle inclines greatly during turning, The lower corner of the touches the ground and responds
Grip the ground securely and do not skid.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which a three-wheel industrial vehicle according to the present invention is applied to a forklift will be described with reference to the drawings. FIG. 1A shows a three-wheeled forklift viewed from the rear, and FIG. 1B shows a rear view of the three-wheeled forklift viewed from the bottom. Masts 1, 1 are mounted on the vehicle body, a driver's seat is formed at the front of the vehicle body, and drive wheels 2, 2 as front wheels are provided on the left and right. At the rear of the vehicle body, a counterweight 3 for adjusting the balance of the vehicle during cargo handling is arranged. Below the counterweight 3, one steering wheel 4 as a rear wheel is provided at the center. I have.

On the bottom surface of the counterweight 3, rubber sheets 5 and 5 as contact members are firmly adhered to both corners, which are portions in contact with the ground, so as not to peel off, and are formed to have high friction resistance. . The rubber sheets 5 and 5 may be simply adhered to the bottom surface of the counterweight 3. Although not shown, a concave portion is formed on the counterweight side, and the back surface of the thick rubber sheet is formed in the concave portion. It is desirable to take measures to prevent falling off, such as fitting or using a bolt or the like.

The three-wheeled forklift thus formed is driven, for example, on the lower left surface, or when stopped on that surface, as shown in FIG. 2, the rubber sheet 5 attached to the lower surface of the counterweight 3 is pressed against the ground, and the vehicle is driven by the left driving wheel 2 and the rear steering wheel 4,
It is grounded at three points with the surface of the rubber sheet 5. Accordingly, in a three-wheeled industrial vehicle, it is generally said that the maximum inclination angle is less than 20 degrees. However, in the three-wheeled forklift according to the present embodiment in which the rubber sheet 5 is mounted, the inclined surface is 30 degrees or more. As a result, the vehicle has a stability equivalent to that of a four-wheeled industrial vehicle without being depressed and displaced.
If the contact member is provided so as to protrude below the vehicle bottom surface, the inclination angle of the vehicle with respect to the ground can be reduced.

[0009] The same is true for a rapid turn during running, whereby a gentle turning run utilizing the advantages of three wheels is realized by securely gripping the ground in an inclined posture and suppressing side slip.

In the above embodiment, the rubber sheet is adhered to the left and right sides of the bottom surface of the counterweight as a portion that contacts the ground, but as illustrated in FIG. In addition, when a chamfered portion is formed at an angle such that the entire surface comes into contact with the ground in a state where the vehicle is inclined, and the rubber sheet 5 is adhered to the chamfered surface 6, the contact area with the ground is increased, which is more effective. Further, in order to form a large frictional resistance, in addition to sticking a rubber sheet as a contact member, a large number of rubber pins 7, 7,. Can be implanted, the material can be changed from rubber to synthetic resin, and furthermore, the counterweight itself can be formed by roughening the surface such as knurling the surface directly. In the above embodiment, the front wheel is a driving wheel and the rear wheel is a steering wheel. However, the present invention is not limited to this, and the rear wheel may be a driving wheel or the front wheel may be a steering wheel. Further, depending on the type of vehicle, a portion that comes into contact with the ground may be provided in a portion of the vehicle other than the counterweight.

According to the present invention, when the vehicle body is tilted, the lower corner portion of the vehicle, such as a counterweight, contacts the ground at the maximum tilt angle, and responds so as not to tilt further. Depending on the difference, it is expected that the portion in contact with the ground may not be at the rear position, but the same is true in that case. Further, the portion that contacts the ground is not limited to the counterweight, and may be a portion other than the counterweight. And the three-wheeled industrial vehicle of the present invention can be suitably used for industrial vehicles other than forklifts.

[0012]

According to the three-wheeled industrial vehicle of the present invention, the portion of the vehicle that comes into contact with the ground is formed with a large frictional resistance, so that displacement and side slip at the time of incline are prevented, and stability equivalent to that of a four-wheeled vehicle is achieved. As a result, the operability unique to the three-wheel system can be exhibited without losing the steering characteristics inherent to the three-wheel system. or
For example, if a contact member is provided at a portion of the counterweight that contacts the ground so as to protrude below the vehicle bottom surface, implementation is easy and the inclination angle of the vehicle with respect to the ground can be reduced. In particular, if the lower corner is chamfered and the chamfered portion is formed with a large frictional resistance, the contact area with the ground is increased, which is effective in preventing slip.

[Brief description of the drawings]

FIGS. 1A and 1B are explanatory views illustrating a three-wheel industrial vehicle according to the present invention for a forklift.

FIG. 2 is an explanatory view showing that an inclined vehicle is stably supported on an inclined surface.

FIG. 3 is an explanatory diagram showing an example of changing a surface that is in contact with the ground.

FIG. 4 is an explanatory view showing a modification example of a surface having a large frictional resistance.

FIGS. 5A and 5B are explanatory views showing the results of a tilt test on a conventional three-wheeled industrial vehicle.

[Explanation of symbols]

1. Mast, 2. Drive wheel, 3. Counterweight, 4. Steering wheel, 5. Rubber sheet, 6. Beveled surface, 7. Rubber pin, 8. Surface plate.

Claims (6)

[Claims] 1. A three-wheeled industrial vehicle in which, when the vehicle body is tilted laterally to the maximum allowable angle, a portion of the vehicle that contacts the ground has a large frictional resistance. 2. The three-wheel industrial vehicle according to claim 1, wherein the portion of the vehicle that contacts the ground is a counterweight. 3. The three-wheeled industrial vehicle according to claim 1, wherein the portion in contact with the ground comprises a contact member having a large frictional resistance. 4. The three-wheeled industrial vehicle according to claim 1, wherein the portion in contact with the ground protrudes below a bottom surface of the vehicle. 5. The three-wheeled industrial vehicle according to claim 3, wherein the contact member is a rubber sheet. 6. The vehicle according to claim 2, wherein the lower left and right corners of the vehicle are chamfered, and the chamfered portion is newly formed as a portion which comes into contact with the ground, and the portion is formed to have a large frictional resistance. Three-wheeled industrial vehicle.