JP4152082B2 - Work vehicle with traversing system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a work vehicle having a traversing system such as a forklift that can be switched to traverse traveling.
[0002]
[Prior art]
Conventionally, as a working vehicle having this type of traversing system, forklifts having a traversing system as disclosed in, for example, Japanese Patent Laid-Open No. 2000-309497 are provided.
[0003]
In this conventional configuration, a front wheel and a rear wheel are provided on the vehicle body so that the front wheels and the rear wheels can be switched, and the pair of left and right front wheels are linked to the drive shaft on the travel drive device side. It is attached to the turning member provided so as to be rotatable around. The turning means for turning the turning member is configured to turn both turning members in opposite directions by a common operating device. Here, as a common operating device, a turning cylinder is adopted, and the rear wheel can be forcibly converted by the cylinder.
[0004]
In a forklift having such a conventional traversing system, the configuration shown in FIG. 7 is provided as a hydraulic circuit for each cylinder. That is, the oil in the tank 80 is supplied to the control valve device 83 via the pump 82 driven by the engine 81. This control valve device 83 is provided with four-port (multiple-port) electromagnetic valves 83A, 83B, 83C, 83D.
[0005]
For example, the hydraulic circuit 84A from the electromagnetic valve 83A is connected to the rear wheel cylinder 85, the hydraulic circuit 84B from the electromagnetic valve 83B is connected to the front wheel turning cylinder 86, and the hydraulic circuit 84C from the electromagnetic valve 83C is tilted. A hydraulic circuit 84D connected to the cylinder 87 and connected from the electromagnetic valve 83D is connected to the lift cylinder 88.
[0006]
[Problems to be solved by the invention]
However, in the above conventional hydraulic circuit, the control valve device 83 uses two-port electromagnetic valves 83A and 83B to turn the wheels. When a plurality of attachments for loading and unloading are attached and cylinders for these attachments are provided, the control valve device 83 has an increase in the number of electromagnetic valve ports. Problems such as having to take a large place of installation occur.
[0007]
Therefore, the invention according to claim 1 of the present invention is a type that can traverse by turning the front wheel and the rear wheel, and the operation of the hydraulic cylinder of the turning means for turning the front wheel and the rear wheel. An object of the present invention is to provide a work vehicle having a traversing system made possible by a one-port electromagnetic valve.
[0008]
[Means for Solving the Problems]
In order to achieve the above-described object, the work vehicle having the traversing system according to claim 1 of the present invention is configured such that the pair of left and right front wheels and the pair of left and right rear wheels are each 90 degrees with respect to the vehicle body side. Each of the conversion means is provided with a hydraulic cylinder, the hydraulic circuit from the electromagnetic valve of the control valve device is connected to one hydraulic cylinder, and the other hydraulic means is provided. The hydraulic circuit of the cylinder is connected to the hydraulic circuit of the one hydraulic cylinder via a switching valve means, and the switching valve means is provided in each of the supply and exhaust oil passage portions in the hydraulic circuit of the other hydraulic cylinder. An off-valve, a controller for controlling these shut-off valves, and a transverse mode switch installed under the switching lever for operating the electromagnetic valves. The traverse mode switch is operated by operating a switching lever to switch the electromagnetic valve, and a signal from the traverse mode switch is transmitted to the controller so that the shut-off valve in the closed state is opened. It is characterized by being comprised so that it can switch to .
[0009]
Therefore, according to the first aspect of the present invention, the left and right front wheels and the left and right rear wheels are directed in the front-rear direction during normal traveling. And when switching to traverse from the normal running, by operating the operation lever actuates the respective換向means. That is, the hydraulic cylinder of the diverting means is operated, and the front wheel and the rear wheel are rotated around the vertical axis so as to be converted into a 90-degree shape (true lateral shape) with respect to the vehicle body. After the front wheels and the rear wheels are thus converted into a lateral shape, the work vehicle can be traversed left and right. At that time, by operating the switching lever to switch the electromagnetic valve, one hydraulic cylinder can be operated by the hydraulic pressure from the control valve device via the hydraulic circuit, and the traverse operated by operating the switching lever By transmitting a signal from the mode switch to the controller, it is possible to transmit an operation output from the controller to a pair of shut-off valves, and to switch both shut-off valves to the open side, thereby from the hydraulic circuit of one hydraulic cylinder. Ri by the branched hydraulic pressure may operate the hydraulic cylinder of the other side.
[0010]
According to a second aspect of the present invention, there is provided a work vehicle having the traverse system according to the first aspect, wherein a mast is provided on the front end side of the vehicle body and a fork is provided on the mast side. It is a thing.
[0011]
Therefore, according to the invention of claim 2, by operating the lift lever, the fork can be moved up and down along the mast, so that the desired fork work can be performed.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to FIGS.
A forklift (an example of a work vehicle) 1 shown in FIG. 2 is provided with a pair of left and right front wheels (drive wheels) 3 at the front of a vehicle body 2 and a pair of left and right rear wheels (reversing wheels) 4 at the rear. And a driving unit 5 is provided above the front portion of the vehicle body 2. A mast 6 that can be expanded and contracted in the vertical direction is attached to the front end of the vehicle body 2 so as to be tiltable in the front-rear direction via a connecting shaft 7 in the vehicle width direction. And the mast 6.
[0013]
The mast 6 is composed of a pair of left and right outer frames 9 on the forklift 1 side and a pair of left and right inner frames 10 which are guided by the outer frame 9 and can be moved up and down, and between the outer frame 9 and the inner frame 10. A lift cylinder 11 is provided. Further, a lift bracket 12 that is guided to the inner frame 10 side and that can freely move up and down is provided, and a pair of left and right forks 13 is provided on the lift bracket 12 via a pair of upper and lower finger bars.
[0014]
The driving unit 5 includes a seat 14, a normal traveling handle 15 positioned in front of the seat 14, a transverse traveling correction lever 16 positioned near the seat 14, and a switching lever 17. The head guard 18 is disposed on the upper side. Further, a counterweight 19 is provided on the main body 2 behind the seat 14.
[0015]
As shown in FIGS. 2 to 4, the pair of left and right front wheels 3 are provided so as to be able to be converted into a 90-degree shape (true lateral shape) with respect to the vehicle body 2 side. That is, on the vehicle body 2 side, a turning member 23 that is rotatable around a longitudinal axis 22 through a bearing device 20 and a longitudinal axis 21 is provided.
[0016]
The swivel member 23 has an inverted L shape, and its horizontal plate portion is connected to the lower end of the vertical axis 21, and travel drive means 25 is provided on the vertical plate portion. The travel drive means 25 is composed of an electric motor 26, a speed reducer 27, and the like, and is attached to the vertical plate portion via a mount of the speed reducer 27. At that time, the rotating flange from the speed reducer 27 becomes a sideways axle 28, and the rim 3A of the front wheel 3 is directly attached to the axle 28 via a connector.
[0017]
Thereby, the turning member 23 is rotatably provided around the longitudinal axis 22 with respect to the vehicle body 2 side. The pair of left and right front wheels 3 are interlocked with traveling drive means 25 attached to the turning member 23, respectively. Here, the front wheel 3 is configured to be positioned almost directly below the vertical axis 22.
[0018]
A battery 75 is mounted on the vehicle body 2 side, and a controller 76 is attached to the battery 75. Cables 77 from the controller 76 are connected to the electric motor 26, respectively.
[0019]
Front wheel turning means 30 for rotating the turning member 23 is provided on the vehicle body 2 side. That is, the front wheel turning means 30 has a hydraulic cylinder 31 for turning the front wheel. The hydraulic cylinder 31 has a main body 31a attached to the vehicle body 2 side through a vertical pin 32 so as to be swingable. The pinton rod 31b is connected to a link 33 fixed to the turning member 23 on one side via a connecting pin 34 in the vertical direction so as to be relatively rotatable. The arms 35 connected from the left and right turning members 23 are connected to each other via a link body 36 and a connecting pin 37 so as to be relatively rotatable.
[0020]
Therefore, by rotating the turning member 23 via the link 33 by the operation of the hydraulic cylinder 31, the front wheel 3 on one side can be turned around the longitudinal axis 22 and directed in a lateral direction, and the arm 35 can be turned. The front wheel 3 on the other side can be turned around the longitudinal axis 22 through the link body 36 or the like, and can be oriented in a lateral direction. That is, according to the front wheel turning means 30, the left and right front wheels 3 are turned in opposite directions by the operation of the common hydraulic cylinder 31 so as to face right side. An example of the front wheel turning means 30 is configured by the above 31-37 and the like.
[0021]
The pair of left and right rear wheels 4 are provided so as to be able to be turned 90 degrees (true lateral shape) with respect to the vehicle body 2. That is, the rims 4A of the pair of left and right rear wheels 4 are attached to the vertical plate portions of the inverted L-shaped turning members 43 so as to be freely rotatable via the lateral axle 44 or the like. Further, the horizontal plate portion of the turning member 43 is provided so as to be rotatable around the vertical axis 42 with respect to the vehicle body 2 via the bearing device 40 and the vertical axis 41. At this time, the rear wheel 4 is configured to be positioned almost directly below the longitudinal axis 42.
[0022]
Rear wheel turning means 50 for turning the left and right rear wheels 4 around the longitudinal axis 42 is provided, and the rear wheel turning means 50 includes a turning cylinder 51 and a hydraulic cylinder for turning the rear wheel. 52 or the like. That is, the turning cylinder 51 has a main body 51a arranged in the vehicle width direction and fixed to the vehicle body 2 side, and piston rods 51c connected to the piston 51b project from both sides in the vehicle width direction.
[0023]
The hydraulic cylinders 52 for turning the rear wheels are a pair of left and right, and each main body 52a is integrated (connected) to both ends of the turning cylinder 51 from which the piston rod 51c is projected via a connecting member 53. Has been. At that time, the piston rods 52c connected to the pistons 52b of the hydraulic cylinders 52 respectively protrude outward in the vehicle width direction. The arm body 54 connected to the upper end of the vertical axis 41 and the projecting end of the piston rod 52c are connected to each other via a link 55, vertical connection pins 56 and 57, and the like so as to be relatively rotatable. Yes.
[0024]
According to the rear wheel turning means 50, the turning cylinder 51 is operated by moving the piston rod 51c in the vehicle width direction with respect to the fixed main body 51a, and the piston rod of the turning cylinder 51 is operated. The main body 52a of the hydraulic cylinder 52 is moved in the vehicle width direction integrally with 51c.
[0025]
The operation of the turning cylinder 51 is performed by an orbit roll (fully hydraulic power steering) by turning the handle 15. The hydraulic cylinders 52 are provided in a pair of left and right so that the rear wheel 4 can be rotated when the turning cylinder 51 is in a neutral state, and is configured to have a predetermined non-operating posture when the turning cylinder 51 is operated. Yes.
[0026]
Therefore, by operating the hydraulic cylinder 52, the vertical axis 41 is rotated via the link 55, the arm body 54, and the like, so that the rear wheel 4 is turned around the vertical axis 42 via the turning member 43 and the like. And can turn straight sideways. That is, by the operation of the hydraulic cylinder 52, the left and right rear wheels 4 are turned in opposite directions and are oriented in a lateral direction. The above 51 to 57 and the like constitute one example of the rear wheel turning means 50 for turning the pair of left and right rear wheels 4 around the vertical axis 42.
[0027]
FIG. 1 shows a hydraulic circuit for each cylinder. That is, the oil in the tank 60 is supplied to the control valve device 63 via the pump 62 driven by the engine 61. The control valve device 63 is provided with, for example, 5 ports (a plurality of ports) of electromagnetic valves 63A, 63B, 63C, 63D, and 63E.
[0028]
For example, a hydraulic circuit 64A from the electromagnetic valve 63A is connected to the first attachment cylinder 65 for cargo handling, etc., and a hydraulic circuit 64B from the electromagnetic valve 63B is connected to the hydraulic cylinder 31 for turning the front wheel. The hydraulic circuit 64C from 63C is connected to the second attachment cylinder 66, the hydraulic circuit 64D from the electromagnetic valve 63D is connected to the tilt cylinder 8, and the hydraulic circuit 64E from the electromagnetic valve 63E is connected to the lift cylinder 11. It is configured.
[0029]
As described above, the hydraulic circuit from the control valve device 63, that is, the hydraulic circuit 64B from the electromagnetic valve 63B is connected to the hydraulic cylinder (one hydraulic cylinder) 31 for turning the front wheel, and turning the rear wheel. The hydraulic circuit 64F of the hydraulic cylinder 52 (the other hydraulic cylinder) is connected to the hydraulic circuit 64B of the hydraulic cylinder 31 via the switching valve means 70.
[0030]
Here, the switching valve means 70 is installed below the switching lever 17 and a shutoff valve 71 provided in each of the oil supply and discharge oil passage portions of the hydraulic circuit 64F, a controller 72 for controlling these shutoff valves 71, and the switching lever 17. The transverse mode switch 73 is configured so that a signal from the transverse mode switch 73 is transmitted to the controller 72. The shut-off valve 71 is a poppet-type electromagnetic switching valve in which a check valve (check valve) 71a and a communication passage 71b are switched by an electromagnetic coil to open and close both supply and discharge oil passage portions. Yes.
[0031]
The operation in the above embodiment will be described below.
The solid line in FIG. 2, FIG. 3, and FIG. At this time, the left and right front wheels 3 and the left and right rear wheels 4 are directed in the front-rear direction. Such a forklift 1 can travel by an operator sitting on the seat 14 of the driving unit 5 operating the handle 15. That is, the electric power of the battery 75 is controlled by the controller 76 and then supplied to the electric motor 26 via the cable 77, and the electric motor 26 is driven to drive the front wheels via the speed reducer 27, the axle 28, and the like. 3 can be driven forward and backward, so that the forklift 1 can be moved forward and backward.
[0032]
Then, by operating the lift lever, the electromagnetic valve 63E in FIG. 1 is switched and the lift cylinder 11 is operated via the hydraulic circuit 64E, so that the fork 13 is lifted and lowered along the mast 6 via the lift bracket 12 and the like. So that the desired fork work can be done. Further, by operating the tilt lever to switch the electromagnetic valve 63D and operating the tilt cylinder 8 via the hydraulic circuit 64D, the mast 6 can be tilted (tilted) around the connecting shaft 7, thereby lifting the bracket. The posture of the fork 13 can be changed via 12 or the like.
[0033]
In the above-described traveling movement, the vehicle is turned according to the steering of the handle 15. That is, for example, by turning the handle 15 to the left, the piston rod 51c of the turning cylinder 51 is actuated to the left by the orbit roll, and the main bodies 52a of both hydraulic cylinders 52 are integrally moved to the left via the connecting member 53. Moved. At this time, both the hydraulic cylinders 52 are in a non-operating posture with a predetermined contraction limit and play a link-like role. Therefore, the leftward movement of both hydraulic cylinders 52 is transmitted to the arm body 54 via the link 55, whereby the turning member 43 can be turned around the longitudinal axis 42, and the rear wheel 4 can be turned leftward.
[0034]
Further, when the piston rod 51c of the turning cylinder 51 is actuated to the left side to the limit, the left and right rear wheels 4 can be converted into a reverse C-shape, thereby enabling turning on the spot. In the same manner as described above, for example, the handle 15 can be turned to the right by turning it to the right.
[0035]
When switching from such normal traveling to transverse traveling, first, the turning cylinder 51 is positioned in a neutral state (straight forward state). By operating the switching lever 17 in this state, the front wheel turning means 30 can be turned, and at the same time, the rear wheel turning means 50 can be turned.
[0036]
That is, in the front wheel turning means 30, by operating the switching lever 17, the electromagnetic valve 63B is switched, and the hydraulic cylinder 31 is contracted by pressure oil via the hydraulic circuit 64B. As a result, the turning member 23 is rotated around the longitudinal axis 22 through the link 33, so that the front wheel 3 is moved relative to the vehicle body 2 as shown in the phantom line of FIG. 2, FIG. 5 and FIG. 6. To 90 degrees (straight side). At this time, the traveling drive means 25 is rotated integrally with the turning member 23. Since the front wheel 3 is positioned almost directly below the vertical axis 22, the front wheel 3 and the like can be made compact and can be turned 90 degrees.
[0037]
Further, in the rear wheel turning means 40, as described above, by operating the switching lever 17, the transverse mode switch 73 installed under the switching lever 17 is operated, and a signal from the transverse mode switch 73 is sent to the controller 72. To communicate. Then, an operating output is transmitted from the controller 72 to the pair (two sections) of shut-off valves 71 in the switching valve means 70, so that both the shut-off valves 71 where the check valve 71a side is in the operating position are connected to the communication passage 71b side. You can switch to
[0038]
As a result, the hydraulic oil in the hydraulic circuit 64B branches to the hydraulic circuit 64F to extend both hydraulic cylinders 52, and the protruding movement of the piston rod 52c is transmitted to the arm body 54 via the link 55, so that the turning member 43 is moved. 2, the rear wheel 4 is turned 90 degrees (true lateral shape) with respect to the vehicle body 2 as shown in the phantom line in FIG. 2, FIG. 5, and FIG. 6. . Since the rear wheel 4 is positioned almost directly below the vertical axis 42, the rear wheel 4 and the like can be made compact and can be turned 90 degrees.
[0039]
In this way, the sensor detects that the front wheel 3 or the rear wheel 4 has been converted, that is, the front wheel 3 or the rear wheel 4 has been converted to a lateral direction, and switches the electromagnetic valve 63B to the closed side. At the same time, both shut-off valves 71 are switched to the check valve 71a side, and the indicator lamp is turned on, thereby enabling the transverse mode.
[0040]
Therefore, in the forklift 1, the operator sitting on the seat 14 of the driving unit 5 controls the electric power of the battery 75 through the cable 77 after controlling the power of the battery 75 by the controller 76 in the same manner as described above. The forklift 1 can be traversed left and right by driving the electric motor 26 to drive and rotate the front wheels 3 in the forward and reverse directions. At that time, the pair of left and right rear wheels 4 can follow and rotate.
[0041]
It is to be noted that the straight traveling correction at the time of traversing can be easily performed by tilting the correction lever 16 back and forth to finely operate the hydraulic cylinder 31 and finely adjusting the angle of the front wheel 3. At that time, since both shut-off valves 71 are on the check valve 71a side, it is easy to control only the hydraulic cylinder 31 for turning the front wheel without contracting the hydraulic cylinder 52 for turning the rear wheel. It becomes possible.
[0042]
By carrying out the transverse running in this way, for example, a long object can be easily conveyed via the fork 13.
In the above-described embodiment, the hydraulic circuit 64B from the electromagnetic valve 63B in the control valve device 63 is connected to the hydraulic cylinder 31 for turning the front wheel, and the hydraulic circuit 64F of the hydraulic cylinder 52 for turning the rear wheel is The hydraulic circuit 64B of the hydraulic cylinder 31 is connected via the switching valve means 70. The hydraulic circuit 64B from the electromagnetic valve 63B is connected to the hydraulic cylinder 52 for turning the rear wheel, and the front wheel is changed. The hydraulic circuit of the hydraulic cylinder 31 for the direction may be connected to the hydraulic circuit 64B of the hydraulic cylinder 52 through the switching valve means 70.
[0043]
In the above-described embodiment, a pair of shut-off valves 71 for switching the check valve 71a and the communication passage 71b are used as the switching valve means 70. However, this is an electromagnetic switching valve of another type. May be.
[0044]
In the above-described embodiment, the counter-type forklift 1 is shown as the work vehicle. However, the work vehicle can be similarly operated even if it is a large transport vehicle, a loader, a side forklift or the like.
[0045]
In the above-described embodiment, the form in which the electric motor 26 is used as the travel drive means 25 is shown, but this may be in the form in which a hydraulic motor is used. In this case, a two-pump, two-motor type hydraulic drive system, a one-pump, two-motor type hydraulic drive system, or the like can be employed as the drive format of the forklift 1.
[0046]
In the above-described embodiment, a form in which the common front wheel turning means 30 for rotating the pair of left and right front wheels 3 at the same time is provided is shown. It may be of a form in which it is individually rotated by the wheel turning means.
[0047]
In the above-described embodiment, a form in which the common rear wheel turning means 50 for rotating the pair of left and right rear wheels 4 at the same time is provided is shown. The rear wheel 4 may be steered by a handle wheel, and the other rear wheel 4 may be a swivel caster. In this case, when switching to traverse, one rear wheel 4 is forcibly converted by the rear wheel turning means. Let
[0048]
【The invention's effect】
According to the first aspect of the present invention described above, when switching from the normal traveling state in which the left and right front wheels and the left and right rear wheels are directed in the front-rear direction to traversing, the respective conversion means are operated, By operating the hydraulic cylinder of the direction means, the front wheel and the rear wheel can be turned around the longitudinal axis to turn 90 degrees (true transverse) with respect to the vehicle body, so that the work vehicle is traversed left and right it can. At that time, by operating the switching lever to switch the electromagnetic valve, one hydraulic cylinder can be operated by the hydraulic pressure from the control valve device via the hydraulic circuit, and the transverse mode operated by operating the switching lever By transmitting a signal from the switch to the controller, an operating output is transmitted from the controller to a pair of shut-off valves, and both shut-off valves are switched to the open side, thereby branching from the hydraulic circuit of one hydraulic cylinder. can operate the hydraulic cylinders of the other side Ri by the hydraulic pressure by which while a form that can換向to face the front and rear wheels just beside form, the electromagnetic valve for rampant in the control valve device to be a one-port Therefore, the installation gap (installation location) of the control valve device is minimized. It is possible.
[0049]
According to the second aspect of the present invention, by operating the lift lever, the fork can be moved up and down along the mast to perform the intended fork work. In this way, the normal fork work can be performed, but the front and rear wheels can be steered so as to face in a horizontal direction, and for example, a long object can be easily transported through the fork. be able to.
[Brief description of the drawings]
FIG. 1 is a hydraulic circuit diagram of a work vehicle having a traversing system according to an embodiment of the present invention.
FIG. 2 is a side view of the work vehicle having the traversing system during normal traveling.
FIG. 3 is a schematic plan view emphasizing a turning structure during normal traveling of a work vehicle having the traverse system.
FIG. 4 is a schematic plan view emphasizing a turning means during normal traveling of a work vehicle having the traverse system.
FIG. 5 is a schematic plan view emphasizing a turning structure when the work vehicle having the traverse system is traversed.
FIG. 6 is a schematic plan view emphasizing a turning means when the work vehicle having the traverse system is traversing.
FIG. 7 is a hydraulic circuit diagram of a work vehicle showing a conventional example and having a traversing system.
[Explanation of symbols]
1 Forklift (work vehicle)
2 Car body 3 Front wheel 4 Rear wheel 5 Driving unit 6 Mast 7 Connecting shaft 8 Tilt cylinder 11 Lift cylinder 13 Fork 15 Handle 16 Correction lever 17 Switching lever 20 Bearing device 22 Vertical axis 23 Turning member 25 Traveling drive means 26 Electric motor 30 Front wheel turning means 31 Hydraulic cylinder 33 for turning the front wheel Link 35 Arm 36 Link body 40 Bearing device 42 Vertical axis 43 Turning member 50 Rear wheel turning means 51 Turning cylinder 52 Hydraulic cylinder for turning the rear wheel 54 Arm body 55 Link 62 Pump 63 Control valve device 63A Electromagnetic valve 63B Electromagnetic valve 63C Electromagnetic valve 63D Electromagnetic valve 63E Electromagnetic valve 64A Hydraulic circuit 64B Hydraulic circuit (one hydraulic circuit)
64C Hydraulic circuit 64D Hydraulic circuit 64E Hydraulic circuit 64F Hydraulic circuit (the other hydraulic circuit)
65 Cylinder for first attachment 66 Cylinder for second attachment 70 Switching valve means 71 Shut-off valve 71a Check valve (check valve)
71b Communication path 72 Controller 73 Traverse mode switch 75 Battery 76 Controller

Claims (2)

A pair of left and right front wheels and a pair of left and right rear wheels are provided so as to be able to turn 90 degrees with respect to the vehicle body side, and each turning means is provided. These turning means have a hydraulic cylinder. and, control the hydraulic circuit from the electromagnetic valve of the valve device is connected to one hydraulic cylinder, the hydraulic circuit of the other hydraulic cylinder, which is connected via a switching valve means to the hydraulic circuit of one of the hydraulic cylinder, the switching The valve means is installed under a shutoff valve provided in each of the oil supply and drainage passage portions in the hydraulic circuit of the other hydraulic cylinder, a controller for controlling these shutoff valves, and a switching lever for operating the electromagnetic valves. The transverse mode switch is operated by operating a switching lever to switch the electromagnetic valve. Switch is operated, by the signal from the transverse mode switch is transmitted to the controller, with a transverse system characterized by being configured to shut-off valve in the closed state is switched to the open state work vehicle.   2. The work vehicle having a traversing system according to claim 1, wherein a mast is provided on the front end side of the vehicle body, and a fork is provided on the mast side.

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