JPH07187593A - Hydraulic piping structure of free lift height forklift - Google Patents

Abstract

PURPOSE:To reduce the range of inhibiting the forward field of view produced by a hose guide and a pipe. CONSTITUTION:In a hydraulic piping structure of a free lift height forklift, a pair of right and left hose guides 9, 10 having a substantially groove-like section for storing a hose 13 disposed in such a manner that the front is substantially U-shaped are installed between right and left masts longitudinally in such a manner that the grooves are opposite to each other. One of the hose guides is fixed to an outer mast 1, and the other is fixed to an inner mast 2. Among pipes connected to the upper end part of the hose 13, a fixed hose guide 9 side outer pipe 14 fixed to the outer mast 1 is extended downward along the rear surface of the hose guide 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic piping structure for a free lift type forklift, and more specifically, a hydraulic pressure for connecting an oil control valve on the vehicle body side and a hydraulic actuator for attachment mounted on a lift bracket. Related to piping structure.

[0002]

2. Description of the Related Art Conventionally, as a hydraulic piping structure of a free lift type forklift of a type in which the inner mast is vertically moved without using a lift chain, a U-shaped bend is formed between the left and right masts with respect to the vertical movement of the inner mast. There is known a hydraulic piping structure of a mast piping system in which flexible hoses arranged in a corresponding manner are used.

FIG. 4 is a front view showing a mast device and hydraulic piping structure of a conventional free lift forklift using the above-mentioned U-shaped hose, and FIG. 5 is a plan view showing a simplified plan arrangement thereof. The hydraulic piping structure will be described below. In the drawing, two sets of hydraulic pipes are shown, and a pair of left and right hose guides 36, 37 made of channel members are vertically installed, one set each on the right side and the left side between the left and right masts. Then, in each set, the hose guide 36 arranged on the outer side is provided with the cross beams 31a, 3 of the outer mast 31.
1b is fixed via a bracket (not shown), and the hose guide 37 arranged inside is fixed to the tie beam 32a of the inner mast 32 via a bracket (not shown). In addition, the hose guides 36 and 37 of each set are arranged so that the grooves face each other, and a flexible hose 38 is bent and arranged in a U-shape on the front side so as to follow up and down movements of the inner mast 32 between the grooves. .

However, one end of the hose 38 has a pipe 39 arranged in parallel along the hose guide 36 on the outer mast side.
Is connected to the oil control valve on the vehicle body side through a hose (not shown). The other end of the hose 38 is connected to an upper end of a pipe 40 arranged in parallel along the inner mast-side hose guide 37. The pipe 40 is mounted on a hose pulley 41 mounted on a piston rod 35a of a free lift cylinder 35. It is connected to one end of the connected hose 42. Further, the hose 42 is connected to a hydraulic actuator for attachment (not shown) attached to the lift bracket 33.

Thus, the oil control valve and the hydraulic actuator are connected, and when the inner mast 32 is moved up and down, the U-shaped hose 38 housed in the hose guides 36, 37 changes its bent portion along the groove. However, when the lift bracket 33 is moved up and down, the hose 42 hooked around the pulley moves along the hose pulley 41 to follow it. In each set, the outer hose guide 36 fixed to the outer mast 31 is arranged inside the lift cylinder 34 for raising and lowering the inner mast 32 arranged behind the mast, and the inner hose guide 36 fixed to the inner mast 32. 37 is arranged behind a free lift cylinder 35 for raising and lowering the lift bracket 33 arranged at the center between the masts. Examples of the hydraulic piping structure using the U-shaped hose 42 as described above include JP-B-4-1199 and JP-A-3-73800.

[0006]

However, in the above-mentioned conventional hydraulic piping structure, the hose guides 36 and 37 are provided.
The rear surface side of the groove bottom of, that is,
Since the pipes 39 and 40 are arranged so as to extend along the outer surface side of 37a, the hose guides 36 and 37 are
Moreover, the front field of view was greatly impaired by the pipes 39 and 40. That is, as shown in FIG. 5, the inner mast 32
Inner hose guide 37 and pipe 40 fixed to the
Is located behind the free lift cylinder 35, and does not directly adversely affect the view field obstruction, but the hose guide 36 and the pipe 39 near the mast fixed to the outer mast 31 are not connected to the lift cylinder 3.
The inhibition range D of the anterior visual field was large because it was arranged inward of No. 4.

In view of the above problems, it is a technical problem to be solved by the present invention to reduce the hindrance of the forward visual field due to the hose guide and the pipe in the hydraulic piping structure of the free lift type forklift. .

[0008]

In order to solve the above problems, the present invention is configured as follows. That is, the left and right outer masts erected on the machine stand, the left and right inner masts that are vertically movable on the outer mast, the lift brackets that are vertically movable on the inner mast, and the outer masts at the rear of the left and right masts. In the hydraulic piping structure of a free lift forklift, which is fixed to the left and right lift cylinders for vertically moving the inner mast, and a free lift cylinder for vertically moving the lift bracket fixed to the inner mast between the left and right masts. There is a pair of left and right hose guides each having a substantially groove-shaped cross section to accommodate a hose arranged in a substantially U-shaped front face between the left and right masts, and the hose guides are arranged vertically so that the grooves face each other. Fix one hose guide placed on the outer mast,
At least one of the hose guides which fixes the other hose guide arranged inwardly to the inner mast and is connected to the upper end of the hose and extends downward along the hose guide. The side pipe is arranged along the rear surface of the hose guide.

[0009]

In the hydraulic piping structure for a free lift type forklift according to the present invention constructed as described above, the hose guide and the pipe are overlapped in the front-rear direction and are occupied by both members in the lateral direction (vehicle width direction). Area is reduced. As a result, the hindrance of the forward field of view due to the hose guide and the pipe is reduced.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a front view showing a mast device and a hydraulic piping structure of a free-lift type forklift, and FIG. 2 is a plan view schematically showing their arrangement. As shown in the drawing, the left and right inner masts 2 are vertically movably mounted inside the left and right outer masts 1 erected on the machine base of the forklift, and the lift bracket 3 is vertically movably mounted on the inner mast 2.

Left and right lift cylinders 4 are erected on the lower cross beams 1a of the outer mast 1 on the rear surfaces of the left and right masts, and their piston rods 4a are connected to the upper tie beams 2a of the inner mast 2. A free lift cylinder 5 is erected on the lower tie beam 2c of the inner mast 2 between the left and right masts, and the middle abdomen is supported by the middle tie beam 2b via a bracket (not shown). A chain wheel 7 is provided on the upper end of the piston rod 5a of the free lift cylinder 5 via a chain wheel bracket 6, and the lift bracket 3 is attached via a lift chain 8 mounted on the chain wheel 7. It is designed to be raised and lowered.

Next, in the free lift forklift configured as described above, a hydraulic piping structure for connecting the oil control valve on the vehicle body side and the hydraulic actuator for attachment (both not shown) mounted on the lift bracket 3 side Will be described with reference to FIGS.
In the present embodiment, the pipes when the lift bracket 3 is equipped with two hydraulic actuators for attachment, that is, two sets of pipes are shown. However, the two pipes, one for oil supply and the other for return oil, make up one set. Therefore, in the following description, one set for pipes is 2
Shall mean a book.

On the right side and the left side between the masts, a pair of left and right hose guides 9 and 10 each having a vertically long groove shape are arranged. The hose guides 9 and 10 are arranged so that their grooves face each other, and the hose guide 9 arranged on the mast side has upper and lower parts thereof bracketed to the upper cross beam 1c and the middle cross beam 1b of the outer mast 1. The hose guide 10 which is fixed via 11 and arranged inside is a free lift cylinder 5
The upper and lower parts are fixed to the rear surfaces of the middle tie beam 2b and the lower tie beam 2c of the inner mast 2 via brackets 12 while being arranged on the rear surface.

Hereinafter, in this embodiment, the hose guide 9 fixed to the outer mast 1 is referred to as an outer hose guide, and the inner hose guide 1 fixed to the inner mast 2 is referred to.
0 is called the inner hose guide. On the other hand, between each pair of hose guides 9 and 10 arranged as described above, a flexible hose 13 is arranged so as to be bent in a substantially U-shaped front shape so as to follow up and down movements of the inner mast 2. ing. One end of the hose 13 is connected to the upper end bent portion of the outer pipe 14 arranged along the outer mast 1, and the other end is connected to the upper end bent portion of the inner pipe 15 arranged along the inner mast 2. The hose guides 9 and 10 are supported in a hanging state in a bent state.

Therefore, the outer pipe 14 is disposed so as to extend downward along the rear surface of the outer hose guide 9, that is, the outer surface of the rear flange 9a which constitutes the rear side surface of the groove, and is welded to the hose guide 9. Is connected to the oil control valve on the vehicle body side through a hose (not shown). On the other hand, the inner pipe 15 is provided so as to extend downward along the rear surface side of the groove bottom of the inner hose guide 10, that is, along the outer surface of the web 10a forming the groove bottom.
2 sets which are fixed to the chain wheel bracket 6 of the free lift cylinder 5 while being fixed by welding to the bottom of the middle tie beam 2b and extending forward under the middle tie beam 2b. Is connected to the rear end of the hose 17 that is hooked on the hose pulley 16.

One of the two sets of hose pulleys 16
The pair is mounted on the left side on the same axis as the chain wheel 7, and the other one is mounted on the upper center, and the hose 17 mounted on these hose pulleys 16 has its front end portion not shown in the drawing as a hydraulic actuator of the lift bracket 3. Connected via the connector pipe.

The hydraulic piping structure according to the present embodiment is constructed as described above, and therefore, when the free lift cylinder 5 is acting on the free lift, the hose hooked on the hose pulley 16 attached to the piston rod 5a thereof. The orbiting movement of 17 follows the lifting operation of the lift bracket 3. On the other hand, when the lift cylinder 4 operates to lift, the inner mast 2 and the free lift cylinder 5
The hose guide 10 on the inner side also moves up and down as a unit. At this time, the hose 13 between the left and right hose guides 9 and 10 is
Follow along while changing the bending point along the groove.

In the hydraulic piping structure of this embodiment, as shown in FIG. 2, the outer pipe 14 fixed to the outer hose guide 9 is arranged on the rear surface of the hose guide 9, so that the hose is not hindered. Guide 9 and outer pipe 14
And overlap in the vehicle front-rear direction. As a result, the lateral direction (vehicle width direction) occupied by these two members
As a result, the hindrance of the forward visual field D due to the hose guide 9 and the outer pipe 14 is significantly reduced as compared with the conventional case, and the forward visual field is improved.

Further, the outer pipe 14 is connected to the hose guide 9
When it is arranged on the rear surface side of the groove bottom, at least the outer mast 14 is arranged on the rear surface side as compared with the conventional arrangement which is arranged on the rear surface side of the groove bottom.
It is possible to earn space equivalent to the diameter of. Therefore, since the hose guide 9 can be arranged closer to the lift cylinder 4 side, as shown in FIG. 2, the space S between the left and right hose guides 9 and 10 is widened, and the front view through both guides is improved. become.

In the illustrated embodiment, the case where two sets of hydraulic pipes are provided to correspond to the two hydraulic actuators mounted on the lift bracket 3 has been described.
The number of pipes corresponds to the number of hydraulic actuators, and is not necessarily limited to two sets.
The configuration in which the outer pipe 14 is arranged on the rear surface of the hose guide 9 may be applied to the inner pipe 15 of the inner hose guide 10.

[0021]

As described in detail above, according to the present invention,
In the hydraulic piping structure of a free lift type forklift, there is an effect that the hindrance of the forward visual field due to the hose guide and the pipe can be reduced as compared with the conventional structure, and the forward visual field can be improved.

[Brief description of drawings]

FIG. 1 is a front view from a driver's seat side showing a mast device and a hydraulic piping structure of a free lift forklift according to an embodiment of the present invention.

FIG. 2 is a plan view schematically showing an arrangement of hydraulic piping structures between masts.

FIG. 3 is an exploded perspective view showing a hydraulic piping structure.

FIG. 4 is a front view from the driver's seat side showing a conventional hydraulic piping structure.

FIG. 5 is a plan view showing a simplified arrangement of a hydraulic piping structure between conventional masts.

[Explanation of symbols]

 1 ... Outer mast 2 ... Inner mast 3 ... Lift bracket 4 ... Lift cylinder 5 ... Free lift cylinder 9,10 ... Hose guide 13 ... Hose 14 ... Outer pipe 15 ... Inner pipe

Claims (1)

[Claims] 1. A left and right outer mast that is erected on a machine stand, left and right inner masts that are vertically movable on the outer mast, a lift bracket that is vertically movable on the inner mast, and rear left and right masts. In the hydraulic pressure of a free lift forklift truck, which is fixed to the outer mast and has left and right lift cylinders that vertically move the inner mast, and a free lift cylinder that vertically moves the lift bracket fixed to the inner mast between the left and right masts. In the piping structure, a pair of left and right hose guides having a substantially groove-shaped cross section are arranged vertically so that the hoses arranged between the left and right masts have a substantially U-shaped front face, and the grooves are opposed to each other. , Fix one of the hose guides located near the mast to the outer mast, and At least one of the hose guide-side pipes that fixes the other hose guide to the inner mast and is connected to the upper end of the hose and extends downward along the hose guide. Is a hydraulic piping structure of a free-lift forklift in which is arranged along the rear surface of the hose guide.