JP3997618B2 - Forklift hydraulic piping system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a hydraulic piping device for a forklift, and relates to a hydraulic piping device in which piping for supplying pressure oil to an attachment hydraulic actuator that moves up and down along a mast is provided along a central lift cylinder between left and right masts.
[0002]
[Prior art]
Conventionally, a free lift forklift or a three-stage mast forklift has one rear lift cylinder behind each of the left and right masts, and further has one front lift cylinder at the center between the left and right masts, and A pipe for attachment is provided along the front lift cylinder.
Hereinafter, a conventional attachment hydraulic piping device will be described with reference to FIGS. As shown in the figure, a front lift cylinder 32 (hereinafter simply referred to as a lift cylinder) for raising and lowering an attachment mounted on a lift bracket (not shown) that is raised and lowered along the inner mast 31 is provided between the left and right inner masts 31. Is arranged. The lower end of the lift cylinder 32 is supported by a lower tie beam 31 a that joins the lower part of the inner mast 31, and the upper side is supported by a cylinder support 33. The cylinder support 33 is fixed to the front surface of the intermediate tie beam 31b of the inner mast 31 with bolts.
[0003]
A plurality of hose pulleys 34 are provided at the upper end of the rod of the lift cylinder 32, and a hose 35 is hung on each hose pulley 34. Then, the plurality of hoses 35 passing through the front side of the hose pulley 34 hang downward along the front side of the lift cylinder 32, and then end portions thereof are connected to the attachment hydraulic actuator via connectors.
On the other hand, a joint 36, a pipe 37, a joint 38, and a hose 39 are connected to a hose 35 passing through the rear side of the hose pulley 34, and the hose 39 is connected to a connector 40 fixed to the inner mast 31 at the lower part. That is, the pipe connecting the hose pulley 34 and the connector 40 at the lower part of the mast is constituted by three members, a hose 35, a pipe 37, and a hose 39, and two joints 36, 38 connecting them.
Such a configuration is intended to avoid the straight piping because the cylinder support 33 supporting the upper portion of the lift cylinder 32 is fixed to the front surface of the intermediate tie beam 31b and obstructs the straight piping. .
The pipe 37 is fixed to the intermediate tie beam 31b by a clamp 41, and the hose 39 is fixed to the cylinder body by a clamp 42. The connector 40 is connected to an oil control valve on the vehicle body side through another pipe (not shown).
[0004]
[Problems to be solved by the invention]
However, in the case of the conventional hydraulic piping device, as described above, there is a problem that the number of components constituting the piping passing through the rear side of the hose pulley 34 to the connector 40 at the lower portion of the mast is large, and the joints 36 and 38 are in the middle of the piping. However, there is a problem that there is a high possibility of oil leakage because there are two locations.
[0005]
The present invention has been made in view of the above-described conventional problems. The object of the present invention is to reduce the number of parts of piping from the hose pulley provided in the lift cylinder to the connector at the lower part of the mast, and to prevent oil leakage. It is an object of the present invention to provide a hydraulic piping device for a forklift that is effective in preventing the above-mentioned problem.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is configured as follows. That is, the invention of claim 1 is a hydraulic piping device for a forklift, which is a lift cylinder disposed between left and right masts, a hose pulley provided on a rod of the lift cylinder, and a hose pulley mounted on the lower side. A hose that is connected to a connector fixed to the lower part of the mast, and a tie beam that connects the left and right masts or the lift cylinder. A pipe guide is provided for guiding the hose hanging down through the rear side of the hose pulley so as to change a hanging direction of the hose, and the pipe guide extends in the vertical direction and the hose hanging down through the rear side of the hose pulley is provided . An upper guide part that guides substantially directly below, and a lower part that changes direction so as to pass through the rear side of the tie beam. It is constituted by a guide plate having an interior, the hose to the upper guide portion is one which is fixed with clamps.
[0007]
According to the invention of claim 1 configured as described above, even if there is a member that obstructs the drooping directly under the hose that hangs down the rear side of the hose pulley, the pipe guide guides the hose drooping direction. Interference with the obstructing member can be avoided by switching and guiding. For this reason, it is possible to configure the pipe that reaches the connector through the rear side of the hose pulley with only the hose, and as a result, the number of parts is reduced compared to the conventional case, and the joint is also unnecessary. The possibility of oil leakage can be reduced.
[0008]
In addition , an upper guide portion that guides a hose that extends vertically in the vertical direction and hangs down through the rear side of the hose pulley, and a lower guide portion that guides the hose that passes through the rear side of the tie beam. The hose is fixed to the upper guide portion by a clamp.
[0009]
With the above-described configuration, it is possible to prevent the hose from sideways during the expansion and contraction operation of the lift cylinder, maintain the hose tension, and further prevent the hose from falling off the hose pulley.
[0010]
According to a second aspect of the present invention, in the hydraulic piping device for a forklift according to the first aspect, a guard portion comprising a forward inclined surface or a curved surface is set at the upper end portion of the guide plate. According to such a configuration, it is possible to protect the hose by avoiding contact with the edge of the hose.
[0011]
According to a third aspect of the present invention, in the hydraulic piping device for a forklift according to the first or second aspect, the lower end of the guide plate is welded with the lower end rear surface of the lower guide portion aligned with the upper end surface of the tie beam. And the welding location on the rear side is set to a location excluding the piping region of the hose. According to such a configuration, the hose can be protected from being interfered with the weld bead.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. This embodiment is provided with one rear lift cylinder at the rear of the left and right masts, as well as one front lift cylinder at the center between the left and right masts, as in a free lift forklift or a three-stage mast forklift. It is intended for forklifts equipped with. FIG. 1 is a front view showing a hydraulic piping device of a forklift and its peripheral members, and FIG. 2 is a side sectional view of the same. 3 is an enlarged view of part A in FIG. 1, and FIG. 4 is an enlarged view of part B in FIG.
A front lift cylinder 2 (hereinafter simply referred to as a lift cylinder) is disposed in the center between the inner masts 1 that are moved up and down along the left and right outer masts (not shown). The lift bracket and the attachment attached to the lift bracket are moved up and down along the inner mast 1.
[0013]
The lower end of the lift cylinder 2 is supported by a lower tie beam 1a that joins the lower part of the inner mast 1, and the upper part is supported by a cylinder support 3 that is fixed to the front face of an intermediate tie beam 1b that joins the left and right inner masts 1 by bolts.
Although not shown, rear lift cylinders for raising and lowering the inner mast 1 are arranged behind the left and right masts. The rear lift cylinder is supported by the lower cross beam of the outer mast at the lower end and the cylinder support is provided at the upper side. It is fixed to the outer mast.
[0014]
A plurality of (two cases are shown in the figure) hose pulleys 4 are provided at the upper end of the rod of the lift cylinder 2, and the hoses 5 are respectively hung on the hose pulleys 4. The movable hose 5 that moves along with the hose pulley 4 through the front side of the hose pulley 4 hangs down along the front side of the lift cylinder 2, and the end of the hose 5 passes through a connector to an attachment hydraulic actuator (not shown). Connected.
A fixed hose 5 that hangs down through the rear side of the hose pulley 4 (hereinafter referred to as a rear hose for convenience of explanation) is a guide plate as a piping guide for changing the drooping direction disposed below the hose pulley 4. After being guided by 7 and suspended along the rear surface side of the lift cylinder 2, it is connected to a connector 6 fixed to the lower part of the inner mast 1. The connector 6 is connected to another pipe (not shown), and the other pipe is connected to an oil control valve provided on the vehicle body side.
[0015]
As shown in FIGS. 3 and 4, the guide plate 7 is a vertically long rectangular plate that is bent in a substantially rectangular shape and extends in the vertical direction. The guide plate 7 guides the rear hose 5 hanging down from the hose pulley 4 substantially directly below. It has an upper guide part 7a having a vertical surface and a lower guide part 7b having an inclined surface for changing the direction of the hose 5 so as to hang downward through the rear side of the intermediate tie beam 1b. .
[0016]
The guide plate 7 formed as described above is provided in the central portion of the intermediate tie beam 1 b corresponding to the rear of the lift cylinder 2. That is, the lower guide portion 1b is joined to the upper end of the intermediate tie beam 1b by butt welding in a state where the lower end rear surface is aligned with the rear surface of the intermediate tie beam 1a. In this case, the welded portion 11 (see FIGS. 3 and 4) of the guide plate 7 with respect to the intermediate beam 1b is set over the entire length of the mating surface on the front side, but excludes the piping region of the rear hose 5 on the rear side. It is set only at the intermediate portion of the part, that is, the mating surface.
Further, the upper end portion of the guide plate 7 is formed in an inclined shape (or curved shape) toward the front to form a guard portion 7 c, thereby preventing the rear hose 5 from hitting the edge.
The two rear hoses 5 are arranged along the rear surface of the guide plate 7 arranged as described above, and are fixed to the upper guide portion 7a of the guide plate 7 by the clamp 8, and further in the middle. The tie beam 1b and the lift cylinder 2 are fixed by clamps 9 and 10, respectively.
[0017]
The hydraulic piping device according to the present embodiment is configured as described above. Accordingly, the guide plate 7 provided below the hose pulley 4 is provided with the rear hose 5 against the cylinder support 3 and the intermediate tie beam 1b which are blocking members for the linear hung of the rear hose 5 existing below the hose pulley 4. The piping can be changed by changing the drooping direction so as not to interfere.
For this reason, it is possible to configure the pipe from the hose pulley 4 to the connector 6 with only the hose 5. As a result, as shown in FIGS. 5 and 6, the rear piping is constituted by three piping members of a hose 35, a pipe 37, and a hose 39 and two joints 36 and 38 that connect them together. Compared to the conventional case, the number of parts is greatly reduced, the assembling work is facilitated, the working time is shortened, and the cost is reduced. Moreover, since no joint is used, oil leakage is reduced.
[0018]
In this embodiment, since the pipe guide is constituted by one rectangular guide plate 7 and the rear hose 5 is fixed by the clamp 8, the structure is extremely simple and can be manufactured at low cost. Further, it is possible to prevent the rear hose 5 from sideways and to maintain the tension and to prevent the hose pulley 4 from falling off.
In addition, since the rear welding portion 11 with respect to the intermediate tie beam 1b is set so as to avoid the piping region of the rear hose 5, the rear hose 5 can be protected from interference with the welding bead. That is, since the hose 5 expands and contracts with the pressure fluctuation of the hydraulic oil when the hydraulic actuator is operated, there is a risk of damage if it is in direct contact with the weld bead. Problem can be solved.
[0019]
When the lift cylinder 2 is in the lowered state, the hose pulley 4 comes closest to the guide plate 7. In this case, if the rear hose 5 can be piped so as to hang down, it does not matter so much, but if it hangs in an inclined manner toward the rear, the rear hose with respect to the upper end of the guide plate 7 There is a risk of damage due to edge 5 hitting the edge. In the present embodiment, since the guard portion is configured with the upper end of the guide plate 7 as a forward inclined surface, the rear hose 5 is not damaged.
[0020]
In this embodiment, the guide plate 7 is joined to the intermediate tie beam 1b of the inner mast 1 by welding. However, the guide plate 7 may be changed to other fixing means such as a bolt or a rivet instead of welding, and the fixing destination thereof may be used. Is not limited to the intermediate tie beam 1b, but may be a cylinder body of the lift cylinder 2, for example.
[0021]
【The invention's effect】
As described above in detail, according to the present invention, in the hydraulic piping device of the forklift, the piping that hangs down through the rear side of the hose pulley and reaches the connector at the lower part of the mast can be configured only by the hose. The number of parts can be reduced, facilitating assembly work and shortening the work time. In addition, the possibility of oil leakage is reduced because a joint is not required.
[Brief description of the drawings]
FIG. 1 is a front view showing a hydraulic piping device and its peripheral members according to the present embodiment.
FIG. 2 is a side sectional view of the same.
FIG. 3 is an enlarged view of a portion A in FIG.
4 is an enlarged view of a portion B in FIG.
FIG. 5 is a front view showing a conventional hydraulic piping device and its peripheral members.
FIG. 6 is a side sectional view of the same.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Inner mast 2 ... Lift cylinder 1a ... Lower tie beam 1b ... Intermediate tie beam 4 ... Hose pulley 5 ... Hose 6 ... Connector 7 ... Guide plate 7a ... Upper guide part 7b ... Lower guide part

Claims (3)

A lift cylinder disposed between the left and right masts, a hose pulley provided on a rod of the lift cylinder, and hung on the hose pulley and suspended downward, one end connected to the attachment hydraulic actuator, and the other end A hose connected to a connector fixed to the lower side of the mast, and a tie beam that connects the left and right masts, or the lift cylinder, so as to change the hanging direction of the hose that hangs down the rear side of the hose pulley. A pipe guide for guiding is provided , and the pipe guide extends in the vertical direction and passes through the rear side of the tie beam, and an upper guide part that guides a hose that hangs down through the rear side of the hose pulley substantially below. A lower guide part that changes direction and guides the upper guide part. Hydraulic delivery apparatus for a forklift in which the hose is secured by the clamp. Guide plate hydraulic pipe system for a forklift according to claim 1, wherein setting the guard portion comprising a forwardly facing inclined surface or curved surface on the upper end portion of. The lower end of the guide plate is joined to the upper end surface of the tie beam by welding in a state where the lower end rear surface of the lower guide portion is flush with the upper end surface of the tie beam, and the weld bead on the rear surface side is located at a portion excluding the hose passage area. The hydraulic piping device for a forklift according to claim 1 or 2 , wherein the hydraulic piping device is set.

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