JP2000233900A - Rough terrain fork lift - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a mast lower part from being an obstacle in a rough terrain by pivotally supporting the lower end of a main mast on the front end of a chassis frame by a mounting bracket, so as to be substantially in the same height as the chassis frame, and arranging a tilting cylinder between it and the chassis frame so as to be tiltable. SOLUTION: The lower end of a main mast 34 is supported on the front end of a chassis frame 2 via a mounting bracket so as to be substantially in the same height as the chassis frame 2. The main mast 34 is tilted by a mast tilting cylinder 42 to slightly rock the lower end upward but is basically held substantially in the same height as the chassis frame 2, so as not to approach the ground or a road surface. According to this, since the lower end of the main mast 34 for guiding the lowering of a fork 49 to the road surface is substantially at the height of the chassis frame 2 and not close to the road surface, the main mast 34 is movable without interfering with the irregularities or undulation of a rough terrain.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forklift, and more particularly to a forklift capable of lifting and conveying articles packed in a container such as a pallet on smooth ground or a road surface. The present invention relates to an uneven terrain forklift used for harvesting agricultural crops such as lotus roots when moving on uneven terrain with undulations, uneven ground such as fields, paddy fields, and lotus fields, and the bottom.

[0002]

2. Description of the Related Art At present, various types of forklifts are used in various fields such as a production site such as a factory premises, a construction site, a warehousing business, a distribution business, and the like. It is premised that it is used in flat places such as road, floor and floor.

FIG. 8 shows a typical example of a conventional forklift.
Shown in In the conventional forklift 64, a hanger 68 having a fork 67 at a lower end is provided on a mast 66 which can be tilted by a mast tilting cylinder 65 so as to be vertically movable by a rolling roller 69. The hanger 68 is hung on one end of a chain 70 suspended by a pulley 69, and the other end of the chain 70 is pulled up and down by a cylinder (not shown) or the like to be pulled up to stop the operation of the cylinder. The hanger 68 is lowered by gravity.

[0004] Such a conventional forklift 64 is
The fork hanger 68 is lowered by its own weight, and since it is necessary to guide the hanger 68 to the ground, the mast 66 has a structure extending below the chassis 71 and near the ground. Further, in the conventional forklift 64, in order to travel on a smooth road surface or the like, a small diameter wheel is sufficient if it can travel. Further, a traveling drive device and a direction change (steering) device transmit power from a single engine or motor to wheels via a propeller shaft and a differential device, and make a turn using a steering wheel.

[0005]

In recent years, various agricultural machines have been actively introduced in the field of agriculture, but forklifts are also used for transporting and lifting agricultural materials, crops, and the like. This is remarkable due to the intensive and large-scale farming and the aging of farmers.

[0006] In the agricultural field, unlike forklifts used in premises such as factories, not only are forklifts used for normal use on smooth roads and the like, but also rough terrain such as irregularities and undulations are produced. , It is often used in the fields. Furthermore, the work of harvesting lotus roots in a lotus field often involves work in muddy water in winter, and it is expected that the lotus roots will be moved into the water by a forklift and used for harvesting work.

By the way, the conventional forklift as shown in FIG. 8 has the following problems when used in the agricultural work field as described above. Conventional forklifts that are assumed to travel on smooth roads, etc., have a mast extending relatively close to the road surface, so when using on uneven terrain, lotus fields, paddy fields, etc. It is difficult to move because it interferes with unevenness, undulation, undulation, muddy water, etc. In addition, since the fork cannot be pressed against the mud bottom of the lotus with a pressing force due to its own weight of the hanger, it is inconvenient when scooping up a crop such as a lotus root from below.

In a conventional forklift, wheels having a relatively small diameter that is used only for the purpose of traveling are used. Therefore, in a place with a poor scaffold as described above, particularly in a lotus field, a paddy field, etc., wheels are attached to a mud bottom. As a result, they cannot move and cannot move, and even if they can move, their mobility is poor.

In a conventional forklift, since it is assumed that the forklift is used in a smooth place, the power of a prime mover such as an engine or a motor is transmitted to wheels through a normal differential device. In paddy fields, fields, etc.
It is not suitable for agile, powerful turning, turning, etc.

The counterweight attached to the rear end of the body of a conventional forklift is made of a casting and has a fixed weight. However, in the field of agriculture, materials, fertilizers, harvests, and the like to be conveyed are not limited to one type, but include various types and weights from light to heavy. Therefore, if the counterweight can be appropriately adjusted according to the weight of the conveyed object depending on the type and content of the work, safety is important. It is important to improve fuel efficiency, as well as the need for lightweight ways.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problem of the conventional forklift, in which the lower end of a mast for guiding a fork is installed at a relatively high position from a road surface, and the wheels have a large diameter. An oil motor is attached to each of the left, right and front and rear wheels, and the counter weight is easily adjusted as a water tank type. Another object of the present invention is to realize a forklift on uneven terrain.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a chassis frame, an engine, a plurality of hydraulic pumps driven by the engine, a fork mechanism, and four large-diameter left and right front and rear wheels. A forklift having four oil motors for driving each of the four wheels, and a counterweight, and suitable for use on uneven terrain having unevenness, a field, a lotus field, and a paddy field; The right and left rear wheels are directly connected to the output shafts of the oil motors fixed to the chassis frame, respectively, and the axle connecting member is vertically arranged at the center of the front end of the chassis frame by a boss shaft extending in the front-rear direction and horizontally. The left and right front wheels of the four wheels are output from an oil motor fixed to both ends of the axle coupling member. Each of the oil motors driving the left front and rear wheels is directly driven by a first hydraulic pump of the plurality of hydraulic pumps, and each of the oil motors driving the right front and rear wheels is connected to the plurality of hydraulic pumps. Driven by a second hydraulic pump, the fork mechanism section includes a main mast, an auxiliary mast, and a mast with a fork,
The lower end of the main mast is pivotally supported at the front end of the chassis frame by a mounting bracket and is substantially at the same height as the chassis frame, and is tilted by a tilt cylinder provided between the main mast and the chassis frame. The auxiliary mast is provided so as to be able to reciprocate in parallel to the main mast by a first cylinder provided between the main mast and the hydraulic cylinder, the hydraulic cylinder acting in both directions of expansion and contraction. The mast with a fork is reciprocally attached in parallel to the auxiliary mast by a second cylinder provided between the auxiliary mast and the hydraulic cylinder, the hydraulic cylinder acting in both directions of expansion and contraction. The first cylinder and the second cylinder are connected to each other so that a hydraulic path is formed in series with the hydraulic pump. It provides a rough terrain fork lift, characterized in being.

[0013] Of the plurality of hydraulic pumps, each of the first and second hydraulic pumps is a swash plate type hydraulic pump, and the plurality of hydraulic pumps supply oil to the first and second cylinders. And a gear pump for sending oil to the tilt cylinder.

[0014] The counterweight may be a water tank provided with a supply plug and a drain plug, which may be configured so that the weight of the counterweight can be adjusted by the amount of water.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a forklift according to the present invention. FIG. 1 is a side view showing an overall configuration of an embodiment of an uneven terrain forklift 1 according to the present invention. The rough terrain forklift 1 is mainly composed of a chassis frame 2, a cabin 3, an engine unit 4, a counterweight 5, a fork mechanism 6, front wheels 7, and rear wheels 8.

FIG. 2 is a plan view showing the overall arrangement of the main parts with the chassis frame 2 at the center. The chassis frame 2 is formed in a rectangular shape from left and right frames 9 and 10, front and rear end frames 11 and 12, and a center frame 13.

The engine 1 is mounted on the rear of the chassis frame 2.
4, the engine 14 is mounted on the chassis frame 2
On the engine mount 15 with screws via an engine mounting bracket 16. Engine 14
A fan 17 and a radiator 18 are disposed at the rear of the fan.

In front of the engine 14, a swash plate type first hydraulic pump 19, which is driven by a drive shaft of the engine 14,
A triple pump of a swash plate type second hydraulic pump 20 and a gear hydraulic pump 21 is arranged.

The left and right frames 9 of the chassis frame 2
The left and right rear motor mounting brackets 22 and 23 are fixed to both sides of the rear portion of the motor 10.
Left and right rear oil motors 24, 25 are provided in mounting holes 2 and 23.
Is inserted and fixed by bolts via the mounting member 26. As will be described later, the left and right rear oil motors 24, 25
Are rotationally driven by a swash plate type first hydraulic pump 19 and a swash plate type second hydraulic pump 20, respectively.

Left and right front axle connecting members 27 are disposed above the front end frame 11 of the chassis frame 2.
Left and right front motor brackets 28 and 29 are vertically provided at both left and right ends of the axle connection member 27, and left and right front oil motors 30 and 29 are provided in mounting holes of the brackets 28 and 29.
31 are inserted and fixed similarly to the left and right rear oil motors 23 and 24. As will be described later, the left and right front oil motors 30 and 31 are respectively swash plate type first hydraulic pumps 19 and
The swash plate type second hydraulic pump 20 is driven.

FIG. 3 is a view showing the details of the structure for attaching the axle connecting member 27 to the front end frame 11. FIG.
FIGS. 3A and 3B are side views, and FIG. 3C is a plan view as viewed from C-C in FIG. 3A. Front and rear bifurcated boards 32 are suspended, and hold the front end frame 11 therebetween. A boss shaft 3 extending in the front-rear direction is provided at the center of the front end frame 11.
The forked plate 32 is pivotally connected to the boss shaft 33. As a result, the axle connecting member 27 is tilted left and right around the boss shaft 33 as shown in FIG. 3B, and the left and right front wheels 7, 7 are smoothly tilted along the uneven surface even on uneven terrain having unevenness. Can be moved.

The left, right, front and rear wheels 7 and 8 of the forklift 1 are connected directly to the output shafts of oil motors 23, 24, 30, and 31, respectively, and are driven independently by a so-called four-wheel independent drive system. is there. In addition, the uneven terrain forklift 1 is completely different from a conventional forklift, and has large-diameter wheels 7, 8 as shown in FIG. Therefore, to be able to run on uneven terrain, lotus fields, muddy fields, etc. without any problems,

The fork mechanism 6 is composed of a pair of left and right main masts 34, 34, auxiliary masts 35, 35 and masts 36, 36 with forks as main parts. FIG.
5 shows the detailed structure of the fork mechanism 6, and the fork mechanism 6 will be described in more detail with reference to FIGS. FIG. 5 (a), (b), (c)
6 is a sectional view of DD, EE, and FF of FIG. 4, respectively. The pair of left and right main masts 34, 34 are made of a steel mold having a concave cross section, and as shown in FIGS. 5B and 5C, at the upper and lower ends, respectively, on the outer surface and the back surface of the main masts 34, 34. Connected by fixed upper and lower connecting members 37 and 38,
Reinforced.

As shown in FIG. 5 (c), the lower ends of the mounting brackets 39, 39 extending rearward at the lower ends of the pair of left and right main masts 34, 34, respectively, are integrated with or separate from the connecting member 38. Installed. On the other hand, support brackets 40, 4
The mounting brackets 39, 39 of the main masts 34, 34 are pivotally mounted on support shafts 41, 41 by the support brackets 40, 40.

Further, mast tilt cylinders 42, 42 are mounted between the pair of left and right main masts 34, 34 and the chassis frame 2, respectively. Thus, the operation of the mast tilting cylinder 42 allows the main mast 34 to tilt around the support shaft 41.

A feature of the present invention is that the lower end of the main mast 34 is attached to the chassis frame 2 via a mounting bracket 39.
The main mast 34 is tilted by the mast tilting cylinder 42, and the lower end of the main mast 34 is slightly swung downward. However, basically, it is necessary to hold the chassis frame 2 at a position substantially the same as the height of the chassis frame 2 so as not to approach the ground or a road surface.

The pair of left and right auxiliary masts 35, 35 are made of a steel mold having a concave cross section like the main mast 34, and
4 and is disposed parallel to the main mast 34 adjacent to the inside of the main mast 34. As shown in FIG. 5B, the pair of left and right auxiliary masts 35, 35 are connected to each other by a top connecting plate 43 on the rear surface of the upper end.

The auxiliary mast 35 has a plurality of running rollers 44 rotatably mounted on its outer surface by bearings. The running rollers 44 roll on the concave inner surface of the main mast 34. Thereby, the auxiliary mast 35 can reciprocate with respect to the main mast 34 adjacent to the inside of the main mast 34.

A pair of right and left first hydraulically operated first cylinders 45, 45 are attached between a connecting member 38 at the lower end of the main mast 34 and a top connecting plate 43 of the auxiliary mast 35. Unlike the hydraulic cylinder that operates the chain of a conventional chain-type forklift, the first cylinder 45 exerts an acting force in both the upward and downward directions of the extension direction and the contraction direction, as described later, so that the auxiliary mast 35 is moved upward and downward. It moves while applying force.

Masts 36, 36 with a pair of left and right forks
Is made of a sectional steel having a concave cross section like the main mast 34,
The auxiliary mast 35 is disposed adjacent to and parallel to the auxiliary mast 35. As shown in FIG. 5A, the pair of left and right masts 36 with forks are connected to each other by a top connecting plate 46 on the upper surface of the upper end.

The fork mast 36 has a plurality of running rollers 47 rotatably mounted on the outer surface thereof by bearings.
Rolling on the concave inner surface. Thereby, the mast 36 with a fork can reciprocate with respect to the auxiliary mast 35 adjacent to the inside of the auxiliary mast 35.

A pair of left and right second cylinders 48 are mounted between the connecting member 43 at the upper end of the auxiliary mast 35 and the top connecting plate 46 of the mast 36 with fork.
Like the first cylinder 45, the second cylinder 48 acts in both the up and down directions of the extension direction and the contraction direction, and reciprocates the fork mast 36 while applying force upward and downward. A fork 49 is integrally or separately provided at the lower end of the fork mast 36. The auxiliary mast 35 and the fork mast 36 expand and contract to move the fork 49 up and down.

As described above, the auxiliary mast 35 reciprocates with the main mast 34 and the mast 36 with the fork so as to be able to expand and contract with respect to the auxiliary mast 35 with an acting force. The arrangement of the main mast 34, the auxiliary mast 35, and the mast 36 with a fork in the inward and outward directions is not limited to the above embodiment. The masts 36 may be arranged. Also, they may be arranged sequentially in the front-rear direction instead of inward and outward directions.

FIG. 6 is a view showing the overall configuration of a hydraulic operating mechanism for operating the rough terrain forklift 1 according to the present invention. The swash plate type first hydraulic pump 19 operated by the engine 14 passes through a collection valve (a valve for diverting an equal amount of oil) 50 as shown by a solid line arrow to the a port of the left front oil motor 30 and the a port of the left rear oil motor 24. Divide an equal amount of oil into

Thus, the left front oil motor 30 and the left rear oil motor 24 rotate in the forward direction. Port b of left front oil motor 30 and left rear oil motor 2
The oil is recirculated from the b port 4 to the swash plate type first hydraulic pump 19 via the T-shaped valve 51.

As is conventionally known, the swash plate type hydraulic pump can adjust the oil supply amount (oil pressure amount) by adjusting the inclination angle of the swash plate, and furthermore, can adjust the inclination direction of the swash plate. By reversing the direction, the oil feeding direction can be changed to the reverse direction indicated by the dotted arrow, whereby the left front oil motor 30 and the left rear oil motor 24 rotate in the reverse direction. By using such a swash plate type hydraulic pump as the swash plate type first hydraulic pump of the present invention, speed adjustment and forward / reverse rotation are enabled, rotation speeds of front and rear wheels, and forward / reverse operation are enabled.

As for the right front and rear wheels, the left front rear oil motors 30 and 24 are also driven by the swash plate type first hydraulic pump 19.
Similarly, the swash plate type second hydraulic pump 20 drives the swash plate type second hydraulic pump 20 in the forward direction (the oil flow is in the direction of the solid arrow) and in the reverse direction (the oil flow is in the direction of the dotted arrow), and the speed adjustment operation is further performed. Done. The swash plates of the swash plate type first and second hydraulic pumps 19 and 20 are controlled by a well-known swash plate control mechanism by operating an operation lever 52 provided in the cabin 3.

As described above, the right and left front and rear wheels 7 and 8 are controlled in forward and reverse rotation and rotational speed by the swash plate type first hydraulic pump 19 and the swash plate type second hydraulic pump 20 for each of the right and left sides. . Therefore, for example, when the left front wheel and the rear wheel 7 are stopped or in the reverse rotation state, and the right front rear wheel and the rear wheel 8 are in the normal rotation state, the vehicle body can be turned leftward. This turning (steering) operation enables powerful left-right steering and rapid turning even in a work field with extremely poor scaffolding, such as uneven terrain, hasuda, paddy fields, etc., compared to the case where conventional differential equipment is used. Becomes

The gear hydraulic pump 21 sends oil through a switching valve 53 to a mast tilt cylinder 42 that tilts the main mast 34. Now, the mast tilt cylinder 42
When the oil is sent in the direction indicated by the solid arrow, the mast tilting cylinder 42 contracts and the main mast 34 tilts clockwise about the support shaft 41.

The gear hydraulic pump 21 sends oil in series to the first cylinder 45 and the second cylinder 48 via the switching valve 54. First cylinder 45 and second cylinder 48
When the oil is sent in the direction of the solid line arrow, both the first cylinder 45 and the second cylinder 48 operate in the extension direction, and when the oil is sent in the direction of the dotted arrow, both operate in the contraction direction.

Thus, the auxiliary mast 35 and the mast 36 with a fork can be extended upward and contracted downward with an acting force in FIGS. 1 and 4, and can be moved to soft ground such as a lotus field or a paddy field. Even when the fork is slightly bitten, it can be effectively performed. Switching valves 53, 54
Can be operated by an operation lever 63 in the cabin 3.

The front, rear, left and right wheels are, as shown in FIG.
A rubber ring 56 is fixed to the frame wheel 55 by baking. The rubber ring 56 includes a rigid base 57 fixed to the frame wheel 55 by baking, and a plurality of rigid paddles 58 projecting outward from the base 57. Paddle part 5
No. 8 performs a biting action on the ground when moving in a work field with poor scaffolding such as rough terrain, a field, a paddy field, and a lotus field, and generates frictional force, and is also used as a water paddle in water such as a paddy field and a lotus field. Produces power and acts effectively as an amphibious wheel.

1 and 2, the counterweight 5 is disposed on the rear end of the chassis frame 2 behind the engine unit 14. One of the features of the uneven terrain forklift 1 of the present invention is that the counterweight is a water tank 59. A replenishing plug 60 and a drain plug 61 that can be opened and closed are provided at the top and bottom of the water tank 59, respectively. A ventilation opening 62 is formed in the center of the water tank corresponding to the radiator 18. The hot air generated by the engine 14 is cooled by the radiator 18 via the fan 17 and is radiated to the outside through the ventilation opening 62.

When increasing the weight of the counterweight 5 in the operation of transporting relatively heavy materials such as fertilizer, the supply plug 60
Water can be supplied to the water tank 59 in large quantities. or,
When transporting a relatively lightweight material such as hay, the water in the water tank 59 may be drained from the drain cock 61 to make the water tank 59 lightweight. Recently, agricultural fields such as fields, lotus fields, and paddy fields are often equipped with water supply facilities, and it is extremely easy to replenish water. Although the heat generated by the engine 14 is cooled by the radiator 18, the provision of the water tank around the engine 14 has a secondary effect of cooling the heat generated by the engine 14.

The operation of the rough terrain forklift 1 according to the present invention having the above configuration will be described. An operator who uses the rough terrain forklift 1 operates the travel operation lever 52 in the driver's seat in the cabin 3 to control the amount of oil supplied to the swash plate type first and second oil pumps 19 and 20, Alternatively, one of them is stopped or reversely flown, and the rotation state such as the rotation speed and the rotation direction is changed for each left wheel or each right wheel, and driving operations such as speed control, directional turning, forward reversing and the like are performed.

When the worker uses the work on a flat surface such as concrete, the fork 49 is used similarly to an ordinary forklift.
It is possible to move even if is lowered near the road surface. For example,
When transporting, lifting, or lowering a container such as a pallet filled with harvested products, the tilting cylinder is operated to operate the main mast 34 at an appropriate angle, and further, the auxiliary mast 35 and the mast 36 with a fork are moved. By moving up and down, the fork 49 is moved to a position indicated by a solid line or a dotted line in FIG.

When the forklift 1 is used on irregular terrain such as a field having large irregularities or undulations, the auxiliary mast 35 and the mast 36 with fork are raised and the fork is raised (solid line in FIG. 1). Fork position)
Move with. The rough terrain forklift 1 according to the present invention includes:
Unlike a conventional forklift, the lower end of the main mast 34 that guides the fork 49 to descend to the road surface is almost at the height of the chassis frame 2 and is not provided close to the road surface. It can be moved smoothly without any obstacle due to swell or the like.

For example, when a lotus root is harvested in a lotus field, when the lotus root extracted from the mud bottom G in the water is lifted from the mud bottom, the first and second cylinders 45 and 48 use the auxiliary mast 35 and the mast with a fork. 36 is lowered, and the mast 36 with a fork is moved to the second cylinder 4
The fork 49 is lowered and pressed against the mud bottom G by the action force of the hydraulic pressure of 8, and is slightly advanced to lift the lotus root from below.

When moving within the Hasuda, the auxiliary mast 35 and the mast with fork 36 are raised above the water surface (the position of the imaginary line W in FIG. 1), and are moved with the fork 49 raised. It can move smoothly without being disturbed by the mud bottom and without receiving muddy water resistance.

As described above, by adjusting the amount of water in the water tank 59, the weight of the counterweight can be adjusted very easily. In this way, the counterweight can be appropriately adjusted in accordance with the weight of the conveyed material such as materials, fertilizers, and harvests that differ depending on the type of work and the contents, and the weight weight can be adjusted when conveying a heavy object. Light weights can be adjusted to light weights, which ensures safety and improves fuel efficiency by optimizing the weight balance of the vehicle body. In addition, since the water tank 59 as a counterweight is provided around the engine, a very unique function of producing a water cooling effect is exhibited.

The embodiment of the present invention has been described above with reference to the forklift 1 on uneven terrain according to the present invention. However, the present invention is not limited to this embodiment and may be implemented within the scope of the technical idea described in the claims. It goes without saying that there are various aspects.

[0052]

Since the present invention has the above-described configuration,
The following excellent effects are produced. The lower end of the main mast that guides the fork in the vertical direction is located above the ground and the road surface, so when moving on uneven ground, lotus fields, paddy fields, etc. Does not interfere with undulation, muddy water, etc.

All the left, right, front and rear wheels use large-diameter paddle wheels, and each wheel can be driven independently by an oil motor. It has excellent maneuverability without having to take wheels.

Since the water weight is adjustable as the counterweight, the weight can be adjusted in accordance with the weight of the material to be raised and lowered, the material to be conveyed, the harvest, and the like, and excellent effects in terms of safety and fuel efficiency can be obtained.

[Brief description of the drawings]

FIG. 1 is a side view showing an entire embodiment of a forklift according to the present invention.

FIG. 2 is an overall plan view centering on a chassis frame of the forklift according to the present invention.

FIG. 3 is a view showing a support structure of left and right front wheels of a forklift according to the present invention.

FIG. 4 is a diagram illustrating a fork mechanism of the forklift according to the present invention.

FIG. 5 is a diagram showing a cross section of a main part of FIG. 4;

FIG. 6 is a diagram illustrating a hydraulic operation of the forklift according to the present invention.

FIG. 7 is a diagram showing a structure of a wheel used in the present invention.

FIG. 8 is a diagram showing an example of a conventional forklift.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Uneven terrain forklift 2 Chassis frame 3 Cabin 4 Engine part 5 Counter weight 6 Fork mechanism part 7 Front wheel 8 Rear wheel 19 Swash plate type first hydraulic pump 20 Swash plate type second hydraulic pump 21 Gear hydraulic pump 24, 25, 30, 31 Oil motor 27 Axle connecting member 34 Main mast 35 Auxiliary mast 36 Mast with fork 42 Main mast tilting cylinder 45 First cylinder 48 Second cylinder 49 Fork 59 Water tank

Claims (3)

[Claims] 1. A chassis frame, an engine, a plurality of hydraulic pumps driven by the engine, a fork mechanism, four large-diameter front and rear wheels, four oil motors for driving each of the four wheels, and An uneven terrain forklift having a counterweight, suitable for use on uneven terrain having unevenness, a field, a lotus field, and a paddy field, wherein the left and right rear wheels among the four wheels are oil fixed to a chassis frame, respectively. An axle connecting member is directly connected to the output shaft of the motor, and is pivotally supported at the center of the front end of the chassis frame by a boss shaft extending in the front-rear direction and horizontally so as to be vertically swingable. The left and right front wheels of the four wheels are directly connected to the output shafts of oil motors fixed to both ends of the axle coupling member, and drive the left front and rear wheels. Each is driven by a first hydraulic pump of the plurality of hydraulic pumps, and each of the oil motors for driving right front and rear wheels is driven by a second hydraulic pump of the plurality of hydraulic pumps. A main mast, an auxiliary mast and a mast with a fork, wherein the lower end of the main mast is pivotally supported by a front end of the chassis frame by a mounting bracket and is substantially at the same height as the chassis frame; The auxiliary mast is provided so as to be tiltable by a tilt cylinder provided between the chassis mast and the chassis frame. The mast with a fork is provided so as to be able to reciprocate in parallel with the main mast. A second cylinder on which a hydraulic pressure acts in a reciprocating manner in parallel with the auxiliary mast, and a fork is attached to the lower end thereof integrally or separately, and the first cylinder and the second cylinder are And a hydraulic forklift connected to the hydraulic pump so as to form a hydraulic path in series with the hydraulic pump. 2. The first hydraulic pump according to claim 1, wherein
Each of the hydraulic pump and the second hydraulic pump is a swash plate type hydraulic pump, and the plurality of hydraulic pumps include a gear pump that sends oil to the first cylinder and the second cylinder and sends oil to the tilting cylinder. The rough terrain forklift according to claim 1, wherein: 3. The rough terrain forklift according to claim 1, wherein the counterweight is a water tank provided with a supply plug and a drain plug, and the weight of the counterweight can be adjusted by an amount of water.