JP2000035002A - Hydraulic oil tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the number of parts of a communicating passage for a hydraulic oil tank and to improve workability of assembly thereof by removing an extension hose which has been required conventionally. SOLUTION: A tank wall surface 13 sank in a hydraulic fluid 40 stored in a tank 10 is provided with a communicating passage (communicating pipe 31) making the inside of the tank 10 communicate with the outside thereof. Because the communicating pipe 31 is on the tank wall surface 13 sank in the hydraulic fluid 40, an extension hose which has been required conventionally can be removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic oil tank for storing hydraulic oil used for a cargo handling cylinder, a power steering cylinder and the like in a vehicle such as a forklift.

[0002]

2. Description of the Related Art An example of a conventional general hydraulic oil tank will be described. As shown in a perspective view in FIG. 5, the hydraulic oil tank 10 for storing hydraulic oil is formed in a substantially rectangular box shape, and the upper surface thereof is formed in a step shape in which a front portion is low and a rear portion is high. . The front upper surface plate (labeled with reference numeral 11) and the rear upper surface plate (labeled with reference numeral 12) are continuous with an inclined surface plate 13 which is inclined downward and forward. In this specification, all surfaces forming the hydraulic oil tank are referred to as tank wall surfaces.

A substantially circular opening hole 12a is formed in the rear upper surface plate 12. As shown in the partial cross-sectional view of FIG. 4, a substantially circular plate-shaped tank cover 22 is attached to the rear upper plate 12 so as to cover the opening 12a. The tank cover 22 includes two left and right communication pipes 31 and 32 that communicate the inside and outside of the tank.
Piping hoses 31a, 32a forming a hydraulic circuit are connected to tank outer ends of the communication pipes 31, 32, respectively.

[0004] One of the communication pipes (referred to as the left side in FIG. 4) (referred to as an oil communication pipe) 31 at the inner end of the tank is provided with:
The upper end of the extension hose 31b is connected. The lower end of the extension hose 31b is submerged in the hydraulic oil 40 stored in the tank. The oil communication pipe 31 is, for example, a return pipe or the like, and communicates inside and outside the tank with oil.

The other (rightward in FIG. 4) communication pipe (referred to as an atmosphere communication pipe) 32 is opened above the oil level (reference numeral 41) of the hydraulic oil 40. The atmosphere communication pipe 32 is, for example, a pipe pipe or the like that refuses to return oil from the tank, and communicates the inside and outside of the tank with the atmosphere.

[0006]

SUMMARY OF THE INVENTION Conventional hydraulic oil tank 1
According to No. 0, by connecting the extension hose 31b to the in-oil communication pipe 31, an in-oil communication passage communicating the inside and outside of the tank with the oil was formed. Therefore, the oil communication pipe 31
In addition to this, since the extension hose 31b is required, there is a problem that the number of parts is increased and the assembling workability is reduced. It is possible to abolish the extension hose 31b by extending the oil communication pipe 31, but in this case, the pipe length of the oil communication pipe 31 becomes considerably long,
This is not a preferable measure because the parts management of the tank cover 22 becomes troublesome.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and the problem to be solved by the present invention is to eliminate the conventionally required extension hose,
It is an object of the present invention to provide a hydraulic oil tank capable of reducing the number of parts of a communication passage in oil and improving workability in assembling.

[0008]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 of the present invention relates to an oil tank which communicates with the inside and outside of a tank on the tank wall submerged in hydraulic oil stored in the tank. This is a hydraulic oil tank provided with a communication passage. With this configuration, since the oil communication passage is located on the tank wall surface submerged in the hydraulic oil, the conventionally required extension hose can be eliminated. As a result, the number of components in the oil communication passage can be reduced, and the assembling workability can be improved.

According to a second aspect of the present invention, an opening is provided in the wall of the tank, the lower half of which is submerged in the hydraulic oil, and a tank cover is provided to close the opening. 2. The hydraulic oil tank according to claim 1, wherein an air communication passage is provided at an upper portion of the tank cover for communicating the inside and outside of the tank with the atmosphere. With this configuration, the air communication passage and the oil communication passage can be collectively provided in one tank cover, so that the cost is lower than in the case where the air communication passage and the oil communication passage are individually provided. It is advantageous for reduction.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment A first embodiment will be described with reference to FIGS. 1 is a sectional view of a main part, and FIG. 2 is a perspective view of a hydraulic oil tank with a tank cover removed. Since the present embodiment is a modification of the conventional example, the same parts will be denoted by the same reference numerals, and redundant description will be omitted.

As shown in FIG. 2, the upper surface plate 12 at the rear of the hydraulic oil tank 10 is not provided with an opening hole (see reference numeral 12a in FIG. 5) unlike the conventional example. Instead, a substantially circular opening hole 13 a is formed in the inclined face plate 13 of the hydraulic oil tank 10. As shown in FIG. 1, a tank cover 23 having a substantially circular plate shape is attached to the inclined face plate 13 so as to cover the opening 13a. At the lower part of the tank cover 23, an oil communication pipe 31 that communicates between the inside and outside of the tank is provided. Furthermore, tank cover 2
At the top of 3 is an air communication pipe 3 that communicates inside and outside the tank.
2 are provided. Piping hoses 31a, 32a forming a hydraulic circuit are connected to the outer ends of the tanks of the communication pipes 31, 32, respectively, as in the related art.

As shown in FIG. 1, the oil level 41 of the hydraulic oil 40 stored in the hydraulic oil tank 10 is located substantially at the center of the inclined face plate 13. As a result, substantially the lower half of the opening 13a sinks into the hydraulic oil 40 together with the oil communication pipe 31, and the oil communication pipe 31 communicates inside and outside the tank with the oil. The in-oil communication pipe 31 corresponds to the in-oil communication passage in the present invention.

The upper half of the opening 13a is exposed above the oil surface 41 of the working oil 40 together with the atmosphere communication pipe 32, whereby the atmosphere communication pipe 32 communicates with the inside and outside of the tank. The atmosphere communication pipe 32 corresponds to the atmosphere communication path in the present invention.

According to the above-described hydraulic oil tank 10, since the oil communication pipe 31 is located on the tank wall, that is, the inclined face plate 13, which sinks in the hydraulic oil 40, the conventionally required extension hose 31b (see FIG. 4) is eliminated. Can be. Thus, the number of components of the oil-in-water communication pipe 31 can be reduced, and the assembling workability can be improved.

The lower half of the tank wall is substantially covered with hydraulic oil 4.
0 is formed and the opening 1a is formed.
A tank cover 23 for closing 3a is provided, an oil communication pipe 31 is provided below the tank cover 23, and an atmosphere communication pipe 32 is provided above the tank cover 23.
Thereby, since the atmosphere communication pipe 32 and the oil communication pipe 31 can be collectively provided in one tank cover 23, compared with the case where the air communication pipe 32 and the oil communication pipe 31 are individually arranged. This is advantageous for cost reduction.

[Second Embodiment] A second embodiment will be described with reference to FIG. In the second embodiment, a part of the first embodiment is modified. Therefore, the modified part will be described in detail, and the parts having the same or substantially the same configuration as the first embodiment are denoted by the same reference numerals. Therefore, duplicate description will be omitted.

In the second embodiment, the air communication pipe 32 and the oil communication pipe 31 are individually provided. That is, as shown in FIG. 3, the oil communication pipe 31 is provided with an opening 13 provided in the lower portion of the inclined face plate 13 of the hydraulic oil tank 10.
It is provided on the tank cover 231 that closes the b. The air communication pipe 32 is provided on the upper surface plate 1 at the rear of the hydraulic oil tank 10.
2 is provided in the tank cover 221 that closes the opening hole 12b provided in the tank 2.

In the above-described hydraulic oil tank 10, since the oil communication pipe 31 is located on the tank wall, that is, the inclined face plate 13 submerged in the hydraulic oil 40, the conventionally required extension hose 31b (see FIG. 4) is eliminated. Thus, the number of parts of the oil communication pipe 31 can be reduced, and the assembling workability can be improved.

The present invention is not limited to the above embodiment, but can be modified without departing from the scope of the present invention. For example, the number of the communication pipes 31 and 32 provided in the hydraulic oil tank 10 is not limited to one, and a plurality of communication pipes may be provided. In addition, each communication pipe 31, 32 is
Instead of being provided on the tank cover, it may be provided directly on the tank wall. In addition, each communication passage is provided with each communication pipe 31, 32.
Instead of this, it is also conceivable to make a hole shape opening on the tank wall surface. The tank wall on which the oil communication pipe 31 is provided is not limited to the inclined face plate 13 but may be the front upper face plate 1.
1. Any tank wall, such as a side plate, that sinks into the hydraulic oil 40 may be used.

[0020]

According to the hydraulic oil tank of the present invention, the number of components in the oil communication passage can be reduced and the assembling workability can be improved by eliminating the conventionally required extension hose.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part showing a first embodiment.

FIG. 2 is a perspective view of a hydraulic oil tank with a tank cover removed.

FIG. 3 is a cross-sectional view of a main part showing a second embodiment.

FIG. 4 is a partial sectional view showing a conventional example.

FIG. 5 is a perspective view of a hydraulic oil tank with a tank cover removed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Hydraulic oil tank 12 Rear upper surface plate (tank wall surface) 13 Inclined surface plate (tank wall surface) 12b, 13a Opening holes 23, 221, 231 Tank cover 31 Oil communication pipe (oil communication passage) 32 Air communication pipe (air communication) Passage) 40 Hydraulic oil

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Nobuhiko Aizu 2-1-1 Toyota-cho, Kariya-shi, Aichi F-term in Toyota Industries Corporation (reference) 2D015 BA01 BA04 3F333 AA02 AB13 CB11 DA02 FH06 3H086 AA25 AA27 AE04 AE27

Claims (2)

[Claims] 1. A hydraulic oil tank provided with an oil communication passage which communicates inside and outside the tank with oil inside a tank wall submerged in hydraulic oil stored in the tank. 2. A tank cover is formed in the tank wall, the lower half of which is formed with an opening for sinking hydraulic oil, and a tank cover for closing the opening is provided. 2. The hydraulic oil tank according to claim 1, wherein an air communication passage is provided at an upper portion for communicating the inside and outside of the tank with the atmosphere.