JP2002195491A - Ventilation device of oil tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attach an air breather even if there is no space above an oil tank. SOLUTION: A connection pipe 11 bent nearly in a L shape is disposed at a hole for attaching an air breather bored nearly at the center on the top of the oil tank 1. A pipe 22 mounted above the oil tank 1 with a support member and the connection pipe 11 are connected to each other by a hose 23. An upper opening part of the pipe 22 is closed with a cap 26, and a vent hole 28 is bored on the side surface of the pipe 22. Therefore, the air breather 30 can be attached at an arbitrary position even if there is no space above the oil tank 1 so that the air breather cannot be attached near a hole for attaching the air breather.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil tank ventilating device for ventilating air in an oil tank for storing oil for a hydraulic circuit of a forklift.

[0002]

2. Description of the Related Art In an oil tank for a forklift, a so-called "oil wiping phenomenon" occurs when oil in an oil tank flows out to a pump side during hydraulic operation or when oil in various cylinders flows into an oil tank. In order to eliminate the problem, a vent (air breather) is provided in the oil tank.

FIG. 8 is a perspective view of a conventional oil tank 51 made of sheet metal. An opening is formed in an end of the upper surface of the oil tank 51, and a hydraulic circuit pipe is provided in the opening. In order to perform this, a cover 53 to which a plurality of pipes 52 are fixed is attached. An oil supply port and an air vent for preventing the oil wiping phenomenon are shared by a pipe 54 fixed to the cover 53. That is, the refueling pipe 5
A cap 55 is detachably mounted on the upper part of the cap 4, and a plurality of ventilation holes 56 are perforated around the upper part of the cap 55 as shown in FIG. The ventilation hole 56 perforated in the cap 55 prevents the occurrence of oil wiping due to the pressurization and depressurization of air in the oil tank 51 during operation of the hydraulic circuit during operation of the hydraulic circuit. Further, in the oil tank 51, a plate-shaped sill plate 57 is provided upright to prevent the oil from swaying back and forth when the forklift is suddenly braked and the oil from wiping from the ventilation port 56.

FIG. 10 is a perspective view of an oil tank 61 made of a synthetic resin. At one end of the upper surface of the oil tank 61, a cover 53 as shown in FIG. An opening 62 is formed. On the other end side of the upper surface of the oil tank 61, a hole 63 for ventilation is separately manufactured at the time of resin molding, and a cover 66 to which a pipe 64 having an upper portion as a ventilation hole 65 is fixed is bolted to the hole 63.
It was overlaid by. The resin oil tank 61
Is an oil tank 5 made of sheet metal to be formed by molding.
It is impossible to form the sill plate 57 as shown in FIG.

[0005]

However, in the conventional examples shown in FIGS. 8 and 9, the number of components is increased due to the sill plate 57 and the cap 55 having holes for forming the ventilation holes 56, and the like. There is a problem that the number of manufacturing steps increases accordingly. Further, since the position of the ventilation port 56 provided in the cap 55 on the upper part of the pipe 54 is located at the end of the oil tank 51, it was not possible to completely prevent oil leakage.

Further, in the resin oil tank 61 shown in FIG. 10, since the cover 66 for covering the hole 63 is separately manufactured, there is a problem that the cost is increased. In addition, due to the presence of the opening 62 and the large size of the hole 63 itself, the position of the hole 63 for arranging the ventilation hole 65 is not at the center of the oil tank 61 but at the end. Therefore, there was a problem that it was not possible to cope with the lift operation at the time of sudden braking. Further, when there is no space above the oil tank 61 due to the arrangement of the other members, there is also a problem that the air breather cannot be arranged due to the air breather pipe 64 which is erected above the cover 66. .

[0007] The present invention has been made in view of the above points, and has as its first object to be able to attach an air breather even when there is no space above an oil tank.
In addition, an air breather mounting hole is located in the center of the oil tank to prevent oil from passing through the air breather, especially during sudden braking, to eliminate the oil wiping phenomenon and reduce costs. A second object of the present invention is to provide an oil tank ventilation device.

[0008]

SUMMARY OF THE INVENTION Therefore, in an oil tank ventilation device according to a first aspect of the present invention, there is provided an oil tank ventilation device for ventilating air in an oil tank for supplying oil to a hydraulic circuit system. An air breather is mounted via a connecting member at an arbitrary position away from the air breather mounting hole provided on the upper surface of the oil tank.

With this configuration, even if there is no space for disposing the air breather above the oil tank and the air breather cannot be mounted near the hole for mounting the air breather, the connection through the connecting member is possible. An air breather can be attached at any position.

According to a second aspect of the present invention, the air breather includes a pipe having a hole for ventilation and a cap for covering an opening of an upper surface of the pipe.

Thus, the air breather can be formed with a simple configuration, and the air breather can be manufactured at low cost.

According to a third aspect of the present invention, there is provided an oil tank ventilating apparatus, wherein the pipe is erected vertically, and a vent hole is formed in a side surface of the pipe.

This makes it difficult for dust and dirt to enter the air breather.

According to a fourth aspect of the present invention, the air breather mounting hole is provided substantially at the center of the upper surface of the oil tank.

This makes it possible to prevent the oil from leaking through the air breather even when the oil in the oil tank swings back and forth during operation of a vehicle such as a forklift, especially during sudden braking.

According to a fifth aspect of the present invention, there is provided the oil tank ventilation device, wherein a pipe for connection with the air breather side and disposed in a hole provided on the upper surface of the oil tank and the oil tank are made of synthetic resin. It is characterized in that the pipe is fixed to the upper surface of the oil tank by welding.

Thus, since the pipe for connection to the air breather side and the pipe for connection are simply welded, they can be fixed at low cost and the number of parts can be reduced. In addition, since the pipe is fixed to the oil tank by welding, when the pipe is bent substantially in an L-shape, the direction of one end serving as the connection part of the pipe can be easily and continuously changed in any direction. Can be set.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 4 is a perspective view of an oil tank 1 made of a synthetic resin having the same function as that of the related art. A cover-3 having a plurality of pipes 4 and 5 for hydraulic piping as shown in FIGS.
Is to be overlaid. As shown in FIG. 6, a mounting hole 10 for an air breather is drilled substantially at the center of the upper surface of the oil tank 1 in the vertical and horizontal directions, and the air breather is formed in the mounting hole 10 as shown in FIG. The lower part of the connection pipe 11 which is substantially L-shaped for connection is inserted.

As shown in FIGS. 4 and 5, the connecting pipe 11 is made of a synthetic resin and is formed in a substantially L-shape. The connecting pipe 11 is formed in a cylindrical shape and is open at both ends. . A flange 12 is integrally formed on the outer peripheral surface of the connection pipe 11, and the flange 12 is welded to the oil tank 1 to fix the connection pipe 11 to the oil tank 1.

As shown in FIGS. 5 and 6, a circular welded portion 9 is formed integrally with the periphery of the mounting hole 10 formed in the surface of the oil tank 1 as shown in FIGS. The length is almost the same as the flange 12 of the connecting pipe 11. Then, the lower part of the connecting pipe 11 is inserted into the mounting hole 10 so that the lower surface of the flange 12 of the connecting pipe 11 is brought into contact with the upper surface of the welded part 9 of the oil tank 1.
2 and the welding portion 9 are welded by, for example, ultrasonic melting.
Thereby, the connecting pipe 11 can be securely and easily fixed to the upper surface of the oil tank 1. Further, since the connection pipe 11 is fixed by welding, the direction of the opening 13 at the upper part of the connection pipe 11 can be easily set continuously in any direction. The connection pipe 11 is formed in a substantially L shape because other components of the forklift are arranged above the connection pipe 11.

FIGS. 1 and 2 show a state in which the cover 3 of the oil tank 1 and the connecting pipe 11 are actually arranged. Here, as shown in FIG. 2, a substantially L-shaped support member 21 is provided upright on the upper surface of the cover 2, and a cylindrical pipe 22 is supported and fixed to a tip of the support member 21. The other end of a flexible hose 23 having one end connected to the opening 13 side of the connecting pipe 11 is connected to a lower portion of the pipe 22 arranged in the vertical direction by a stopper 24. The connection between the hose 23 and the connection pipe 11 is also fixed by the stopper 25.

Further, at the upper part of the pipe 22, a cylindrical cap 26 whose upper surface is closed is fixed by a stopper 27. The cap 26 closes the opening of the upper surface of the pipe 22 so that dust is And garbage are prevented from entering. FIG. 1B shows a side view of the pipe 22.
As shown in FIG. 3, a plurality of holes, for example, two holes 28 are formed in the vertical direction as vents. With this hole 28, air can be freely taken in and out of the oil tank 1 through the pipe 22, the hose 23 and the connecting pipe 11. Here, the pipe 22 and the cap 26 constitute an air breather 30 as a ventilation device for discharging the air in the oil tank 1 to the atmosphere.

The air breather 30 has a configuration in which a hole 28 is formed in the side surface of the pipe 22 as compared with a case where a hole for a vent is formed in the cap 55 as in the prior art. Can be In particular,
A hole 28 for ventilation is formed in a side surface of the pipe 22 arranged vertically.
, Making it difficult for dust and dirt to enter the pipe 22. Also, even when the air breather cannot be mounted near the air breather mounting hole 10 because there is no space above the oil tank 1, the connection for the connection bent approximately L-shaped at an arbitrary position away from the mounting hole 10. Air breather 30 from pipe 11 through hose 23
Can be attached.

FIG. 7 shows a state in which the oil 31 in the oil tank 1 swings back and forth during operation of a vehicle such as a forklift truck, particularly during sudden braking. Since the connecting pipe 11 is arranged at a substantially central position on the upper surface of the oil tank 1, the oil 31 does not leak outside through the connecting pipe 11. Further, when the connecting pipe 11 is disposed and fixed to the oil tank 1, the connecting pipe 11 is fixed to the oil tank 1 by welding, so that the cost can be reduced and the number of parts can be reduced. Also, the number of assembling steps can be reduced, and the cost can be reduced as a whole.

[0025]

According to the oil tank ventilation device of the first aspect of the present invention, the connecting member is provided at an arbitrary position away from the air breather mounting hole provided on the upper surface of the oil tank. Since the air breather is installed, there is no space for installing the air breather above the oil tank, even if the air breather can not be installed near the hole for air breather installation, through the connection member An air breather can be attached at any position.

According to the second aspect of the present invention, the air breather is composed of a pipe having a hole for ventilation and a cap for covering an upper opening of the pipe. The air breather can be formed with a simple configuration, and the air breather can be manufactured at low cost.

According to the third aspect of the present invention, since the pipe is erected vertically and a hole for ventilation is formed in a side surface of the pipe, dust and dirt are contained in the air breather. Can be made difficult to enter.

According to the fourth aspect of the present invention, the hole for mounting the air breather is provided substantially at the center of the upper surface of the oil tank. Even if the oil in the oil tank swings back and forth greatly, the oil can be prevented from leaking through the air breather.

According to the fifth aspect of the present invention, the oil tank and the pipe for connection with the air breather side and provided in the hole provided on the upper surface of the oil tank are made of synthetic resin. Since the pipe is fixed to the upper surface of the oil tank by welding, the pipe for connection with the air breather is simply welded to the oil tank, so that the pipe can be fixed at low cost and the number of parts can be reduced. be able to. In addition, since the pipe is fixed to the oil tank by welding, when the pipe is bent substantially in an L-shape, the direction of one end serving as the connection part of the pipe can be easily and continuously changed in any direction. Can be set.

[Brief description of the drawings]

FIGS. 1A and 1B are a plan view and a front view of an oil tank with an air breather according to an embodiment of the present invention attached.

FIG. 2 is a side view of the oil tank with the air breather according to the embodiment of the present invention attached.

FIG. 3 is an enlarged exploded perspective view of an air breather attached to the tip of the hose according to the embodiment of the present invention.

FIG. 4 is a perspective view of the oil tank according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram in a case where a pipe for connecting an air breather according to the embodiment of the present invention is welded to an oil tank.

FIGS. 6A and 6B are an enlarged plan view and a front view of an essential part of an oil tank according to an embodiment of the present invention.

FIG. 7 is an explanatory diagram showing movement of oil in an oil tank at the time of sudden braking according to the embodiment of the present invention.

FIG. 8 is a perspective view of a conventional oil tank made of sheet metal.

FIG. 9 is an enlarged perspective view of a conventional cap provided with a vent.

FIG. 10 is an exploded perspective view of a conventional oil tank made of resin.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Oil tank 10 Mounting hole 11 Connecting pipe 12 Flange 22 Pipe 23 Hose 26 Cap 28 Hole 30 Air breather

Claims (5)

[Claims] An oil tank ventilation device for ventilating air in an oil tank that supplies oil to a hydraulic circuit system, wherein the ventilation device is connected to an arbitrary position apart from an air breather mounting hole provided on an upper surface of the oil tank. An air tank ventilation device, wherein an air breather is attached via a member. 2. The ventilation device for an oil tank according to claim 1, wherein said air breather is constituted by a pipe having a hole for ventilation and a cap covering an upper opening of said pipe. 3. The ventilation device for an oil tank according to claim 2, wherein said pipe is erected vertically and a hole for ventilation is formed in a side surface of said pipe. 4. The ventilation device for an oil tank according to claim 1, wherein the hole for mounting the air breather is provided substantially at the center of the upper surface of the oil tank. 5. A pipe for connection with the air breather side and provided in a hole provided on the upper surface of the oil tank and an oil tank are made of synthetic resin, and the pipe is fixed to the upper surface of the oil tank by welding. The ventilation device for an oil tank according to any one of claims 1 to 4, wherein the ventilating device is used.