JPH09208194A - Hydraulic piping device of fork lift - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the forward visual field without decreasing the load capacity. SOLUTION: In a fork lift in which lift cylinders 3 are respectively provided on the right and left mast back surfaces, and an opening part 4 for visually confirming the front is formed between the masts, a plurality of hose pulleys 9 are longitudinally arranged in parallel on the upper part between the mast and attached to an upper tie beam 2a of an inner mast 2. Hoses 11 are laid on the hose pulleys 9 so that the side communicated with a driving device of the attachment may be outside. Pipes 13 for connecting the hoses 11 to an oil control valve are provided in parallel along the mast back surfaces, and the upper parts 13a are so extended as to be laid inward from the mast and connected to the other ends of the hoses 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forklift hydraulic piping system, and more particularly to a hydraulic piping system suitable for a field-of-view improved forklift in which a lift cylinder is arranged on the rear surface of a mast and a wide opening is formed between the masts. Regarding

[0002]

2. Description of the Related Art Generally, in a forklift truck in which a cargo handling device is equipped with an attachment such as a side shift or a roll clamp, a mast for connecting a drive device (hydraulic cylinder or hydraulic motor) of the attachment to oil on the vehicle body side. Equipped with internal hydraulic piping system.

FIG. 6 shows a conventional general visual field type hydraulic piping system. Two hydraulic pipes are required for each attachment, one for supply and one for return.
The case where six pipes are equipped to accommodate one attachment is shown. In the illustrated hydraulic piping device, hose pulleys 33 for piping are arranged side by side between the left and right inner masts 31 so that the axial direction thereof is parallel to the mast width direction.

Each hose pulley 33 has a hose 3
4 are hooked up, one end of each hose 34 is connected to a drive device of an attachment (not shown) through a connector pipe, and the other end is connected to a pipe 35 for piping below the hose pulley 33. The pipes 35 for each pipe are extended side by side downward in each set, and the lower end portion thereof is connected to an oil control valve (not shown) on the vehicle body side via a hose. As such a side-by-side hydraulic piping device, for example, JP-A-5-2999844 can be cited.

Another example is a hydraulic piping device in which hose pulleys for piping are arranged in parallel in the front-rear direction behind a lift cylinder. There is Japanese Patent Laid-Open No. 59-17498.

[0006]

However, in the case of the above-described conventional side-by-side hydraulic piping system, six hoses 34 are provided between the left and right masts and the opening 3 of the inner mast 31 is provided.
2 will hang down in a side-by-side manner so as to block 2, and the degree of obstructing the front field of view from the driver's seat is large, and the upper portion 35a of the pipe 35 extends inward at a substantially intermediate position of the opening 32. Since it is configured to be connected to the hose 34, the front view is also hindered by that,
There is a problem that the characteristics of the visual field improvement type are lost. On the other hand, in the hydraulic piping device of the type in which the hose pulleys are juxtaposed in the front-rear direction behind the lift cylinder, it is necessary to move the entire cargo handling device including the mast forward in order to secure the space for arranging the hose pulleys. There is a problem that the center of gravity of the cargo handling device moves away from the center of the vehicle and the allowable load decreases.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a hydraulic piping device for a forklift truck that can improve the forward field of view without reducing the allowable load. is there.

[0008]

Means for Solving the Problems In order to solve the above problems, the present invention is configured as follows. That is, the invention of claim 1 is a hydraulic piping device for a forklift of the type in which lift cylinders are arranged behind the left and right masts to form an opening for front visual recognition between the left and right masts. The hose pulley for hose mounting is arranged in parallel in the front-rear direction on the upper part of the space.

According to the invention of claim 1 configured as described above, any number of hose pulleys arranged in parallel in the front-rear direction, including the hose and the pipe connected to the hose, can be used. Can be viewed as a set of pipes from the driver's seat. Therefore, the degree to which the hydraulic pipe blocks the opening between the masts is reduced, and the front field of view is expanded as compared with the side-by-side type, and the effect is higher as the number of pipes increases. Further, since it is arranged between the left and right masts, the arrangement space is easily secured.

According to a second aspect of the present invention, in the forklift piping device according to the first aspect, the hose pulley is
It is characterized in that the hose is mounted so that the side of the attachment connected to the drive device is on the outside. According to the above configuration, the hose can be arranged outside the opening formed between the left and right masts. Therefore, compared to the case where the hose is arranged inward of the opening, it does not hurt the eyes.

According to a third aspect of the present invention, in the piping device for a forklift according to the first aspect, pipes for connecting the hose and the control valve are arranged side by side along the rear surface of the mast. The upper side of the hose extends inwardly of the mast and is connected to one end of the hose. According to the above configuration, most of the pipe is arranged on the rear side of the mast, which is the original blind spot, so that the obstruction of the forward field of view by the pipe is almost avoided. Moreover, since the pipes are arranged side by side, the space in the front-rear direction required for the arrangement is small, and it is therefore not necessary to change the mast position.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the drawings. 1 to 3 are front views of a hydraulic piping device of a forklift viewed from the driver's seat side, FIG. 4 is a plan view thereof, and FIG. 5 is a side sectional view thereof. In the hydraulic piping device according to the present embodiment, the lift cylinders 3 are arranged behind the left and right inner masts 2 arranged in front of the vehicle body to improve the visual field in which the opening 4 for front visual recognition is formed between the masts. Type forklifts are applicable.

As shown in the figure, an inner mast 2 as a movable mast capable of moving up and down along the left and right outer masts 1 as fixed masts is lifted and lowered by a lift cylinder 3 standing on the lower cross beam 1a of the outer mast 1. . The lift bracket 5 that can be moved up and down along the inner mast 2 is moved up and down via a lift chain 7 that is mounted on a chain wheel 6 that moves up and down together with the rod of the lift cylinder 3. The chain wheel 6 and the lift chain 7 are arranged behind the inner mast 2 and close to the inner surface of the lift cylinder 3 so as not to obstruct the front view from the opening 4 between the masts as much as possible.

The hydraulic piping device for the attachment includes a drive device (hydraulic cylinder or hydraulic motor) for operating attachments such as side shifts and roll clamps (not shown) mounted on the lift bracket 5, and an oil control valve 8 on the vehicle body side. And is connected to the outer masts 1 on the left and right so as not to extend outside. Generally, two hydraulic pipes are provided, one for supply and one for return, and in the present embodiment, as shown in the figure, a case is shown in which three sets of hydraulic pipes are distributed to the left and right between the masts.

Above the left and right inner masts 2, three hose pulleys 9 are arranged on the left and right. The left and right hose pulleys 9 are arranged in parallel so as to overlap each other in the front-rear direction with the axial direction thereof as the front-rear direction, and the pulley bracket 1 is provided on the lower surface of the upper tie beam 2a of the inner mast 2.
It is mounted rotatably through 0.

Each hose pulley 9 has a hose 11
Each of the hoses 11 has an outer hanging portion 11a that hangs down from the outside of the hose pulley 9 and is connected to the driving device through a connector pipe 12 and hangs down inside the hose pulley 9. The ends of the inner hanging portions 11b are respectively connected to the pipes 13 at positions slightly hanging from the hose pulley 9. The outer hanging portion 11a of the hose 11 is arranged as close to the inner surface of the inner mast 2 as possible, that is, outside the opening 4 formed between the masts.

The six pipes 13 for connecting the hose 11 and the oil control valve 8 are divided into left and right three pipes, most of which are rear surfaces of the mast, specifically, the rear surfaces of the left and right lift cylinders 3. The pipes are arranged side by side in the left-right direction. Thus, the upper portion 13a of each pipe 13 has an upper cross beam 1 of the outer mast 1.
After extending inward along the lower surface of c, it is bent forward and further folded back at a position corresponding to the hose pulley 9 to be connected to the end of the inner hanging portion 11b of the hose 11. That is, the upper side of the pipe 13 is extended so as to wrap around the inside of the mast and is connected to the hose 11.

The lower portion 13c of each pipe 13 is
It is connected to the oil control valve 8 via a connecting hose 14 in a state of being extended inward slightly above the middle cross beam 1b of the outer mast 1 and further downward. The pipes 13 arranged as described above are connected to each other by a connecting piece 15 welded to appropriate portions in the longitudinal direction so that the left three pipes and the right three pipes can be handled as a set. There is.

Further, the pipe 13 has a portion 13b of the upper portion 13a thereof, which hangs downward for connection with the hose 11, fixed downwardly in the center of the lower surface of the upper cross beam 1c, and the front-back direction is defined as a surface direction. Is fixed to the pipe bracket 16 common to the left and right, which is made of a plate, via a pipe clamp 17, and the lower portion 13c is fixed to the middle cross beam 1b via a pipe clamp 18.

In the hydraulic piping system according to the present embodiment configured as described above, three hose pulleys 9 are provided on each of the left and right sides.
Since they are arranged in parallel so as to overlap each other in the front-rear direction, the hoses 11 mounted thereon also overlap in the front-rear direction. Therefore, when viewed from the driver's seat, when the inner mast 2 shown in FIG. 1 is in the lowered state, the outer hanging portion 11a of the hose 11 for only one hose 11 is provided in the opening 4 between the masts.
Since the outer hanging portion 11a is disposed outside of the opening 4, the degree of eyesore is less than that when passing through the inside.

On the other hand, most of the pipe 13 is behind the lift cylinder 3, which is the original blind spot, and of the upper part 13a which extends so as to wrap around the inside of the mast for connecting with the hose 11. The portion of the outer mast 1 that extends on the lower surface of the upper cross beam 1c overlaps with the upper cross beam 1c or the upper tie beam 2a of the inner mast 2 when viewed from the driver's seat, and falls within the original blind spot range. Therefore, most of the pipes 13 do not block the front view. However, the portion 13b that hangs downward due to the connection with the hose 11 slightly blocks the front, but this also does not significantly obstruct the position, and the conventional hydraulic pressure shown in FIG. The degree of obstruction of the field of view is much smaller than that of the piping device in which the upper portion 35a of the pipe 35 extends inward in the middle of the opening 32.

When the inner mast 2 is raised, the outer hooking portion 11a of the hose 11 rises as shown in FIG. 2, so that the hose 1 is inserted into the opening 4 between the outer masts 1.
1 does not exist at all, and a wide front field of view can be obtained, and as shown in FIG. 3, the upper field of view through the opening 4 between the inner masts 2 is only one hose 11 on each side. Yes, it is greatly improved compared to the conventional one.

From the above, the degree to which the opening 4 for visual recognition of the front formed between the masts is blocked by the hydraulic pipe is greatly reduced as compared with the prior art, and the lift cylinder 3 is moved to the rear of the mast. It is possible to make the most of the features of the field-of-view improved forklift arranged at.

According to the structure in which the hose pulleys 9 are arranged in parallel in the front-rear direction in the upper space between the masts, the degree of blocking the opening 4 does not change even if the number of hydraulic pipes increases. It is highly responsive,
Moreover, since the arrangement space for the hydraulic piping can be easily secured, it is not necessary to displace the entire cargo handling apparatus to the front, unlike the hydraulic piping apparatus of the type in which the hose pulley 9 is arranged behind the lift cylinder 3, and there is a problem that the allowable load is reduced. Does not occur.
In addition, since the portion 13b that hangs downward from the upper portion 13a of the pipe 13 is fixed to the side surface of the common pipe bracket 16, only one pipe bracket 16 is required and the obstruction of the visual field due to it is reduced.

In the present embodiment, the case where piping is provided on both the left and right sides has been described, but it is also possible to change the configuration to provide piping on only one side.

[0026]

As described in detail above, according to the first aspect of the invention, it is possible to improve the forward field of view without reducing the allowable load of the forklift, making the best use of the characteristics of the field-of-view improved forklift. A hydraulic piping system is provided. Further, the degree to which the hydraulic pipe blocks the opening between the masts does not change even if the number of pipes increases, so that the effect increases as the number of pipes increases. According to the inventions of claims 2 and 3, the front visual field can be further improved.

[Brief description of drawings]

FIG. 1 is a front view of a hydraulic piping device when a mast is descending.

FIG. 2 is a front view showing the lower side of the hydraulic piping device when the mast is raised.

FIG. 3 is a front view showing the upper side of the hydraulic piping device when the mast is raised.

FIG. 4 is a plan view of a hydraulic piping device.

FIG. 5 is a side sectional view of a hydraulic piping device.

FIG. 6 is a front view showing a conventional hydraulic piping device.

[Explanation of symbols]

 1 ... Outer mast 2 ... Inner mast 3 ... Lift cylinder 4 ... Opening 9 ... Hose pulley 11 ... Hose 13 ... Pipe

Claims (3)

[Claims] 1. A hydraulic piping device for a forklift of the type in which lift cylinders are respectively arranged at the rear of the left and right masts to form an opening for visually recognizing the front between the left and right masts. A hydraulic piping device for a forklift that has multiple hose pulleys for hose mounting arranged in parallel in the front-rear direction. 2. The hydraulic piping device for a forklift according to claim 1, wherein a hose is mounted on the hose pulley such that the side connected to the drive device of the attachment is on the outside. 3. A hose, in which a pipe for connecting the hose and a control valve is arranged along a rear surface of the mast, and an upper side of the hose extends inward of the mast. The hydraulic piping device for a forklift according to claim 1, which is connected to one end of the.