JP2000355489A - Forklift with latral running system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a turnabout at a usual running time and the sideways- turning of a turnabout wheel at a lateral running time though referring to a four-wheel type. SOLUTION: A drive wheel 3 and a turnabout wheel 4 each are provided on a car body 2 in a possible state of making a turn to an angle of 90 deg.. The drive wheel 3 is provided turnably around a vertical axial center 27 and a drive wheel turn means is provided. The turnabout wheel 4 is provided turnably around the vertical axial center 49 and is equipped with a turnabout wheel turn means 50. The means 50 has a turnabout cylinder 51 operable right and left and a cylinder 53 for the lateral running of a turnabout wheel. The cylinder 53 for the lateral running of a turnabout wheel makes a turn of the turnabout wheel 4 to an angle of 90 deg. while moving the cylinder 51 in a neutral state back and forth and also takes a prescribed nonoperational attitude at the working time of the turnabout cylinder 51.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forklift having a traversing system capable of switching to traversing traveling.

[0002]

2. Description of the Related Art Conventionally, vehicles having a traversing system are found in large-sized transport vehicles, some loaders, and the like, and in forklifts, reach-type electric vehicles exist. Also,
There is a side forklift that handles long objects, with masts and forks attached horizontally to the movement of the vehicle. However, there is no counter-type engine forklift capable of traversing and having the same function as a side fork in addition to the usual work.
In order to establish such a forklift, it is necessary to steer the drive wheels (front wheels) and the turning wheels (rear wheels) so as to face right beside. At that time, both drive wheels are independently turned by an actuator such as a cylinder.

[0003]

However, in the conventional forklift, when turning the turning wheel to the side, the turning by the handle wheel during normal running and the turning in the sideways direction when traversing are compatible. Was difficult. In addition, as a method of achieving both the turning by the handle wheel during normal traveling and the turning in the lateral direction during traversing,
There is a method of changing the turning wheel (steering axle) to one wheel (three-wheeled vehicle type). In this case, if the steering wheel is turned to the locked state at the time of traversing, the diverting wheel can be traversed with the sideways direction, but the three-wheeled vehicle type is less stable than the four-wheeled vehicle type.

[0004] Therefore, the invention described in claim 1 of the present invention has the following four aspects.
It is an object of the present invention to provide a forklift having a traversing system that is capable of performing a turning operation during a normal traveling and a lateral turning operation during a traversing operation, while being of a wheel type.

[0005]

According to a first aspect of the present invention, there is provided a forklift having a traversing system including a pair of left and right driving wheels and a pair of right and left diverting wheels. Each of the drive wheels is provided so as to be able to turn around at 90 degrees, the two drive wheels are provided rotatably around the longitudinal axis with respect to the vehicle body side, and drive wheel rotating means for performing rotation is provided. The diverting wheel is provided so as to be rotatable around the longitudinal axis with respect to the vehicle body side, and diverting wheel rotating means for performing rotation is provided. The diverting wheel rotating means is operable in the left-right direction. A turning cylinder and a turning wheel traversing cylinder. The turning wheel traversing cylinder moves the neutral turning cylinder back and forth to turn the turning wheel in a 90-degree shape. When the turning cylinder is activated, In which was characterized by the attitude.

Therefore, according to the first aspect of the present invention, the right and left driving wheels and the right and left turning wheels are oriented in the front-rear direction during normal running. During normal running, when turning the steering wheel left and right and operating the turning cylinder with the orbit roll, the turning wheel traversing cylinder is in a predetermined non-operation position and serves as a support member, so the handle Can be turned by turning the turning wheel in accordance with the operation of the vehicle. Further, when the turning cylinder is operated to the limit, the left and right turning wheels can be turned in an inverted C-shape, thereby enabling turning on the spot.

When switching from normal traveling to traversing traveling, for example, by operating a lever type traversing mode switch with the turning cylinder in the neutral position, the drive wheel turning means and the turning wheel turning means are operated. Let it. That is, the drive wheel rotating means is operated to rotate the drive wheel around the vertical axis so that the drive wheel is turned 90 degrees (directly to the side) with respect to the vehicle body. In addition, the turning wheel turning means is operated to turn the turning wheel around the vertical axis so that the turning wheel turns 90 degrees with respect to the vehicle body (turns rightward). At this time, the turning wheel rotating means operates the turning wheel traversing cylinder in a state where the turning cylinder is in the neutral (straight-running) position, so that turning of the rear wheel can be easily and smoothly performed. I can do it.

After the driving wheels and the turning wheels are turned right and left in this manner, the driving wheels are driven in the forward and reverse directions, so that the forklift can travel in the left and right directions. At that time, the pair of left and right diverting wheels are rotated following.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
The state employed in a normal forklift will be described with reference to the drawings. 1 to 4, a forklift 1 having a traversing system is provided with a pair of left and right driving wheels 3 at a front portion of a vehicle body 2 and a pair of right and left turning wheels 4 at a rear portion. An operation unit 5 is provided above and in front of. A mast 6 which is vertically expandable and contractible is attached to a front end portion of the vehicle body 2 via a connecting shaft 7 in a vehicle width direction so as to be rotatable in the front-rear direction, and a tilt cylinder 8 for rotating back and forth is provided. Body 2 and mast 6
And provided between them.

The mast 6 includes 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 frames 9 and can move up and down.
0 is provided with a lift cylinder 11. In addition, a lift bracket 12 that is guided by the inner frame 10 and that can move up and down is provided.
A pair of left and right forks 13 is provided via a pair of upper and lower finger bars.

The driving unit 5 is provided with a seat 15 and a handle 16 positioned in front of the seat 15.
A head guard 19 is disposed above the head guard 19 via a front pipe 17 and a rear pipe 18 erected from the main body 2 side. Further, a counterweight 20 is provided on the main body 2 behind the seat 15. The pair of left and right drive wheels 3 and the pair of right and left turning wheels 4 are provided so as to be able to turn 90 degrees relative to the vehicle body 2 (turning right beside). That is, the pair of left and right drive wheels 3 is
Are directly attached to a rotating flange (drive shaft) 22 of a hydraulic motor (travel driving device) 21 via a connecting member 23, so that they are linked to the hydraulic motor 21 side.

The mounting of the hydraulic motor 21 is reverse L
The horizontal plate portion of the turning member 24 is attached horizontally to the vertical plate portion of the U-shaped turning member 24.
5 and the longitudinal axis 26, the longitudinal axis 27 with respect to the vehicle body 2 side.
Are provided so as to be rotatable around. At that time, the vertical axis 2
7 is configured to be located directly above the drive wheel 3.

The hydraulic motor 21, that is, the turning member 2
4 is provided with driving wheel rotating means 30 for rotating the driving wheel 4.
The driving wheel turning means 30 has a driving wheel traversing cylinder 31.
a is swingably attached to the vehicle body 2 via a vertical pin 32, and a pinton rod 30 b is connected to a link 33 fixed to the pivot member 24 on one side by a vertical connecting pin 3.
4 so as to be relatively rotatable. The link body 3 is provided between the arms 35 connected from the left and right vertical axes 26.
6 and a connecting pin 37 for relative rotation.

Therefore, the drive wheel traversing cylinder 31
By turning the turning member 24 via the link 33 by the operation of the above, the driving wheel 3 on one side is turned around the longitudinal axis 27 and turned to the side, and the arm 35 and the link body 36 are moved. The drive wheel 3 on the other side can be turned around the vertical axis center 27 and directed to the side. In other words, according to the drive wheel rotating means 30, the left and right drive wheels 3 are turned in the same direction by the operation of the common front wheel traverse cylinder 31, and are directed to the side. An example of the driving wheel turning means 30 is constituted by the above-described parts 31 to 37 and the like.

In FIG. 7, an engine 40 and a pair of pumps 41 driven by the engine 40 are provided on the vehicle body 2 side. Then, the pump 41 is made to correspond to one hydraulic motor 21, that is, a two-pump two-motor type hydraulic drive system (HS
The corresponding pump 41 and the hydraulic motor 21 are connected via a pipe (eg, a hydraulic hose) 42 so as to form a T system.

1 to 4, a pair of right and left turning wheels 4 is provided.
The rim 4A is freely rotatably attached to a vertical plate portion of the turning member 45 via a lateral axle 46 or the like, and the horizontal plate portion of the turning member 45 is
Via a bearing 47 and a longitudinal axis 48, it is provided rotatably around a longitudinal axis 49 with respect to the vehicle body 2. A turning wheel turning means 50 for turning the pair of right and left turning wheels 4 about a vertical axis 49 is provided. The turning wheel turning means 50 includes a turning cylinder 51 and a turning cylinder operable in the left-right direction. It is composed of a driving wheel traversing cylinder 53 and the like.

That is, the main body 51a of the turning cylinder 51 in the left-right direction is fixed on a movable body 58, and the movable body 58 is connected to the vehicle body 2 via a guide mechanism (not shown) such as a rail. A piston rod 51c connected to the piston 51b is protruded on both sides in the vehicle width direction, and is configured to be operated in the left-right direction by operating the valve 52. I have. The arm 54 and the protruding end of the piston rod 51c connected from the longitudinal axis 48 side are relatively rotatably connected via a link 55, vertical connecting pins 56 and 57, and the like. .

The diverting wheel traversing cylinder 53 has a main body 53a in the front-rear direction attached to the vehicle body 2 side, and is connected to a piston 53b to form a piston rod 53c protruding rearward (or forward). The main body 51 a of the direction cylinder 51 is connected via a connecting pin 59. The turning cylinder 51 is configured to perform a left-right operation or the like by an orbit roll (fully hydraulic power steering) 60 by turning a handle 16.
The diverting wheel traversing cylinder 53 is configured to move the diverting wheel 4 to 90 degrees by moving the neutral diverting cylinder 51 back and forth, and when the diverting cylinder 51 is activated. It is configured to have a predetermined non-operation posture.

That is, when the diverting wheel traversing cylinder 53 is extended to the limit and the diverting wheel 51 is in the neutral state, the left and right diverting wheels 4 are directed in the front-rear direction. When the directional wheel traversing cylinder 53 is contracted and moved, the longitudinal axis 48 is rotated via the link 55 and the arm body 54 and the like, and the diverting wheel 4 is moved around the longitudinal axis center 49 via the turning member 45 and the like. Can be turned right beside.
In other words, by the operation of the turning wheel traversing cylinder 53,
The left and right diverting wheels 4 are configured to diverge in the same direction and to face right beside. An example of the turning wheel turning means 50 that turns the pair of left and right turning wheels 4 around the vertical axis 49 is constituted by the above 51 to 60 and the like.

The operation of the above embodiment will be described below. 1, 2 and 3, FIG. 4 and FIG.
FIG. 7A and FIG. 7 show a state in which the vehicle travels straight in normal traveling. At this time, the left and right driving wheels 3 and the right and left diverting wheels 4 are oriented in the front-rear direction. Such a forklift 1 can travel when an operator sitting on the seat 15 of the driving unit 5 operates the handle 16.

By operating the lift lever to operate the lift cylinder 11, the lift bracket 12 is operated.
The fork 13 can be moved up and down along the mast 6 through the like, and the intended fork operation can be performed. The mast 6 can be rotated (tilted) around the connecting shaft 7 by operating the tilt lever 8 by operating the tilt lever, and thus the fork 1 can be rotated via the lift bracket 12 or the like.
3 can be changed.

In the above-described running motion, the vehicle can be turned in accordance with the operation of the steering wheel 16. That is, for example, handle 1
By turning 6 to the left, the turning cylinder 51 is operated to the left by the orbit roll 60 as shown in FIG. At this time, the turning wheel traversing cylinder 53
Is in a non-operational position with a predetermined extension limit and serves as a support member. Therefore, the piston rod 51c
Is transmitted to the arm body 54 via the link 55, whereby the turning member 45 is turned around the longitudinal axis 49, and the turning wheel 4 is turned to turn left.

As shown in FIG. 5B, when the diverting cylinder 51 is operated to the left to the limit,
The left and right rear wheels 4 can be turned in a reverse U-shape, thereby enabling turning on the spot. When switching from such normal running to traversing running, first, the turning cylinder 51
Is a neutral (straight) position shown in FIG. In this state, for example, a lever-type traversing mode switch (not shown) is operated to operate the driving wheel turning means 30 and the turning wheel turning means 50.

That is, in the drive wheel rotating means 30, the drive wheel traverse cylinder 31 is actuated by tilting the lever, and the turning member 24 is moved to the longitudinal axis 2 via the link 33 or the like.
7, the drive wheels 3 are turned 90 degrees with respect to the vehicle body 2 as shown in the imaginary lines of FIGS. 1 and 2 and FIG. Direction). Here, since the drive wheels 3 are each integrated with the hydraulic motor 21,
The 90-degree turning can be easily and smoothly performed, and since the longitudinal axis 27 is located directly above the driving wheel 3, the driving wheel 3 and the like can be made compact to perform 90-degree turning. Become.

In the turning wheel rotating means 50, a valve 52 is provided.
Causes the diverting wheel traversing cylinder 53 to contract and move, and causes the diverting wheel 5 to move through the piston rod 53c.
1 is moved forward. Then, the conversion cylinder 5
1 and the connecting pin 57 moves forward, and this movement is transmitted to the arm body 54 via the link 55, thereby rotating the turning member 45 about the longitudinal axis 49. As shown in the imaginary line in FIG. 3 and FIGS. 5 (c) and 6 (b), the rear wheel 4 is turned 90 degrees (directly to the side) with respect to the vehicle body 2. At this time, the turning cylinder 51 is in the non-operation position at the contraction limit of the neutral position and performs a link-like role.

When the driving wheels 3 and the diverting wheels 4 are turned in this way, that is, when the driving wheels 3 and the diverting wheels 4 are turned to the side, the sensor detects the turning and turns on the indicator lamp. This allows a traversing mode. Therefore, by supplying the hydraulic pressure from the pair of pumps 41 driven by the engine 40 to the corresponding hydraulic motor 21 via the pipe 42 by the forward / reverse control in the driver's seat 5, the drive wheels 3 are driven in the forward and reverse directions. Drive, so that the forklift 1 can be traversed left and right. At this time, the pair of left and right turning wheels 4 are rotated following.

By being able to perform traversing in this way,
For example, a long object can be easily transported via the fork 13. In the above-described embodiment, a two-pump two-motor type hydraulic drive system is employed as the drive type of the forklift 1, but a one-pump two-motor type hydraulic drive system may be employed.

In the above-described embodiment, a state adopted in a normal forklift 1 is shown. This is, for example, a free-running side forklift used for transporting heavy objects or the like, for example, in a vehicle body side. The pick-up coil provided catches electromagnetic waves on the floor-side induction wire, so that it can be similarly applied to a side forklift or the like that can travel on a given automated conveyance line.

[0029]

According to the first aspect of the present invention, 4
Despite being a wheel type, it is possible to reliably perform the turning during normal running and the turning sideways during traversing without complicated electric control.

[Brief description of the drawings]

FIG. 1 shows an example of an embodiment of the present invention, and is a side view of a forklift having a traversing system during normal traveling.

FIG. 2 is a partially cutaway front view of a front wheel portion of the forklift having the traversing system.

FIG. 3 is a partially cutaway front view of a rear wheel portion of the forklift having the traversing system.

FIG. 4 is a partially cutaway plan view of a rear wheel portion of the forklift having the traversing system.

FIGS. 5A and 5B are explanatory diagrams of an operation of a rear wheel portion of the forklift having the traversing system, wherein FIG. 5A illustrates a turning operation, FIG. 5B illustrates a turning operation on the spot, and FIG.

FIGS. 6A and 6B are schematic plan views of a forklift having the traversing system, wherein FIG. 6A shows a normal traveling state and FIG. 6B shows a traversing traveling state.

FIG. 7 is a schematic plan view of a forklift having the traversing system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Forklift 2 Body 3 Drive wheel 4 Diversion wheel 13 Fork 16 Handle 21 Hydraulic motor (traveling drive) 22 Rotating flange (drive shaft) 24 Revolving member 26 Vertical axis 27 Vertical axis center 30 Drive wheel rotating means 31 Drive wheel traverse Cylinder 33 Link 35 Arm 36 Link body 40 Engine 41 Pump 45 Revolving member 48 Vertical axis 49 Vertical axis center 50 Turning wheel rotating means 51 Turning cylinder 52 Valve 53 Turning wheel traversing cylinder 54 Arm body 55 Link 60 Orbit roll

Claims (1)

[Claims] A pair of left and right driving wheels and a pair of right and left diverting wheels are provided on a vehicle body so as to be able to turn 90 degrees, respectively, and both driving wheels are turned around a vertical axis with respect to the vehicle body side. Driving wheel turning means is provided movably, and the turning wheel is provided so as to be rotatable. The two change-direction wheels are provided rotatably around the vertical axis with respect to the vehicle body side, and the turning wheel is turned. A turning wheel turning means is provided, the turning wheel turning means includes a turning cylinder operable in the left-right direction and a turning wheel traversing cylinder, and the turning wheel traversing cylinder has a neutral shape. The traversing system is characterized in that it is configured to move the diverting wheel back and forth so as to deflect the diverting wheel by 90 degrees, and that the diverting cylinder assumes a predetermined non-operating posture when activated. Forklift.