WO2013086880A1

WO2013086880A1 - Oil tank for excavator and excavator having same

Info

Publication number: WO2013086880A1
Application number: PCT/CN2012/082026
Authority: WO
Inventors: 于文忠; 徐茂林; 郭凤歧; 孙德华
Original assignee: 中联重科股份有限公司; 湖南中联重科专用车有限责任公司
Priority date: 2011-12-12
Filing date: 2012-09-26
Publication date: 2013-06-20
Also published as: CN102493516A; CN102493516B

Abstract

Disclosed is an oil tank for an excavator, comprising an oil tank body (1), a suction oil filter assembly (3), a return oil filter assembly (4) and a first pre-pressed air filter (2), wherein the suction oil filter assembly (3) is located in a suction oil chamber (A) of the oil tank body (1), the return oil filter assembly (4) is located in a return oil chamber (B) of the oil tank body (1), and the first pre-pressed air filter (2) is arranged on the oil tank body (1) and is in communication with the suction oil chamber (A). Also disclosed is a pressure balancing device arranged on the oil tank body (1) for balancing the pressure between the suction oil chamber (A) and the return oil chamber (B). Further disclosed is an excavator having the oil tank.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the field of excavation machinery, and more particularly to an excavator fuel tank and an excavator having the same. BACKGROUND OF THE INVENTION In the prior art, the structure of a hydraulic excavator fuel tank is disclosed in a Chinese patent application with the patent name of an excavator, a hydraulic excavator fuel tank, application number 200920231252.X, as shown in Fig. 1, the excavator fuel tank includes The casing 1', the oil suction filter assembly 2', the oil return filter assembly 3', the oil suction elbow 4' and the preloading air filter 6'. The casing Γ includes an oil suction chamber and a return oil chamber. The oil suction filter assembly 2' is disposed on the lower side of the box body and is located in the oil suction chamber. The oil return filter assembly 3' is disposed on the upper side of the box body and in the oil return chamber, and the excavator fuel tank is used therebetween. The partitions 5' are spaced apart. The pre-pressurized air filter 6' is placed at the top of the tank and communicates with the suction chamber. As shown in Fig. 1, the oil return chamber is surrounded by steel plates and welded to the top and side plates of the box body. The above prior art has the following disadvantages: When the rodless chamber of the excavator cylinder is oiled, and the rod chamber is returned to the oil, the liquid level in the excavator tank is rapidly lowered. During the lowering process, a certain vacuum is formed in the upper part of the oil returning chamber; due to the action of the pre-pressing air filter 6', there will be a certain positive air pressure in the upper part of the oil suction chamber, the magnitude of which depends on the air filter. Preload the value size. Due to the existence of the positive air pressure, a certain height of oil may remain in the oil return chamber and cannot enter the oil suction chamber. The height can be calculated by the following formula:

H 3⁄4=ΔΡ / (ρ -g). Where ΔΡ ^ is the difference between the upper air pressure of the oil suction chamber and the upper vacuum of the oil return chamber. Due to the above reasons, it is necessary to increase the volume of the oil return chamber and the amount of fuel to compensate for the oil at this height (ie, H _3⁄4 ), and the entire volume of the oil tank of the excavator will be correspondingly increased, resulting in unnecessary waste. SUMMARY OF THE INVENTION An object of the present invention is to provide a hydraulic oil that is not retained in a return oil chamber. Under the condition that the excavator system requires the same flow of hydraulic oil, the hydraulic oil refueling amount and the excavator fuel tank volume can be correspondingly reduced. A fuel tank and an excavator having the fuel tank. The present invention provides an excavator fuel tank, comprising: a fuel tank casing, comprising an oil suction chamber and a return oil chamber; an oil suction filter assembly located in the oil absorption chamber; and an oil return filter assembly located in the oil return chamber; a first pre-pressure type air filter disposed in the fuel tank body and communicating with the oil absorption chamber; the excavator fuel tank further comprising: a pressure balance device disposed on the fuel tank body to balance the oil absorption chamber And the pressure of the return oil chamber. Further, the pressure equalization device includes a balance conduit that communicates with the oil suction chamber and the oil return chamber. Further, two ends of the balance duct are respectively detachably connected to the top of the tank body. Further, the pressure balance device includes a second pre-pressure type air filter disposed in the tank body and in communication with the oil return chamber. Further, the fuel tank body includes: a vertical wall disposed around the oil return filter assembly, welded to a top plate and a side plate of the oil tank case; a horizontal partition plate located at a bottom of the vertical wall, The vertical wall, the top plate and the side plates of the fuel tank body together define the oil return chamber. Further, the pressure equalization device includes a communication hole disposed at a top of the vertical wall. Further, an oil return inlet for hydraulic oil flowing into the oil return chamber is disposed on a side plate of the fuel tank body surrounding the oil return chamber; and the hydraulic oil is disposed on the horizontal partition plate The oil return outlet of the oil return chamber. Further, the fuel tank body includes a vertical partition, the vertical partition partitions the interior of the fuel tank body into a first compartment and a second compartment that communicate with each other, and the oil suction filter assembly is located at the first partition a returning oil outlet for the hydraulic oil to flow out of the oil return chamber is located in the second compartment, and a communication portion connecting the first compartment and the second compartment is higher than the oil return outlet. The present invention also provides an excavator including the aforementioned excavator fuel tank. According to the excavator fuel tank of the present invention, due to the action of the pressure balance device, the pressure difference between the oil suction chamber and the oil return chamber is very small or there is no pressure difference, so that there is substantially no retained hydraulic oil in the oil return chamber. The volume of part of the hydraulic oil can be omitted. Under the condition that the excavator system needs the same flow of hydraulic oil, the hydraulic oil refueling amount and the excavator tank volume can be reduced accordingly, thus reducing the amount of oil consumed and the excavator tank. Consumables, saving production and operating costs. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in FIG. In the drawing: 1 is a schematic structural view of an excavator fuel tank of the prior art; FIG. 2 is a schematic structural view of a first embodiment of an excavator fuel tank according to the present invention; and FIG. 3 is a structure of a second embodiment of an excavator fuel tank according to the present invention. schematic diagram. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. As shown in FIG. 2 to FIG. 3, the excavator fuel tank mainly includes a fuel tank casing 1, a first pre-pressing air filter 2, an oil suction filter assembly 3, a return oil filter assembly 4, and a pressure balance device. The fuel tank body 1 includes an oil suction chamber A and a return oil chamber B, and is separated by a vertical wall 7 and a horizontal partition plate 8 at the bottom of the vertical wall. The vertical wall 7 may be disposed around the oil return filter assembly 4 and welded. The top plate of the case 1 and the steel plate on the side plate. The oil suction filter assembly 3 is located in the oil suction chamber A. The oil return filter assembly 4 is located in the oil return chamber B. The first pre-pressure type air filter 2 is disposed at the top of the tank casing 1 and communicates with the oil suction chamber A. The pressure balance device is disposed on the tank body 1 to balance the pressure of the oil suction chamber A and the oil return chamber B. When the excavator cylinder has no rod chamber and the rod chamber returns to oil, the liquid level in the excavator tank drops rapidly. During the liquid level lowering process, a certain vacuum is formed in the oil return chamber B; due to the action of the first pre-pressure type air filter 2, there is a positive air pressure in the oil suction chamber A, so that a positive and negative pressure difference is generated. At this time, due to the action of the pressure balance device, the pressures of the oil suction chamber A and the oil return chamber B can be maintained substantially equal, according to the formula H _3⁄4 = AP _S / (p ^g), the upper air pressure and the oil return chamber of the suction chamber What is the difference in upper air pressure? ^ Approximate to zero, therefore, H _3⁄4 is also approximately zero, does not appear due to pressure difference eight? ^There is a waste of hydraulic oil caused by the inability of some of the oil in the oil return chamber B to be retained, and the problem of correspondingly expanding the volume of the oil tank of the excavator is also solved. As shown in FIG. 2, in the first embodiment of the present invention, the pressure balance means includes a balance duct 5 that communicates the oil suction chamber A and the oil return chamber B. The balance conduit 5 maintains the pressures in the oil suction chamber A and the oil return chamber B substantially equal, thereby solving the problem of waste of hydraulic oil caused by the inability to utilize a part of the oil in the oil return chamber and the technical problem of expanding the volume of the oil tank of the excavator. Specifically, both ends of the balance duct 5 may be detachably coupled to the top of the tank tank 1, respectively. This arrangement facilitates the installation and disassembly of the balance duct 5 and also facilitates the replacement of the filter element in the return filter cartridge assembly 4. As shown in FIG. 3, in the second embodiment of the present invention, the pressure balance device includes a second pre-pressure type air filter 6, which is disposed at the top of the tank casing 1 and communicates with the oil return chamber B. After the second pre-pressure type air filter 6 is provided, the pressure in the oil return chamber B can be made within the control range as the pressure in the oil suction chamber A. When the excavator cylinder has no rod chamber and the rod chamber returns to oil, the liquid level in the excavator tank drops rapidly, and a certain vacuum is formed in the return chamber B. At this time, the second pre-press type air filter The intake check valve in 6 will open, inhale the outside air, so that The oil suction chamber A and the oil return chamber B are under substantially the same environmental conditions, so that the pressure difference ΔΡ _δ can be reduced, thereby reducing the Η _3⁄4 , thereby achieving the purpose of balancing the pressure of the oil suction chamber and the return oil chamber, and solving the aforementioned Technical problem. As shown in FIGS. 2 and 3, a vertical partition 9 is further provided inside the fuel tank casing 1. An oil return inlet 10 for hydraulic oil entering the oil return chamber B is disposed at an upper portion of the side wall of the oil tank casing 1 forming the oil return chamber B, and a hydraulic oil is discharged from the oil return chamber B on the diaphragm 8 Return to the oil outlet 11. The vertical partition 9 divides the interior of the fuel tank casing 1 into a first compartment in which the oil suction filter assembly 3 is located and a second compartment in which the oil return outlet 11 of the oil return chamber B is located. Moreover, the height of the longitudinal partition 9 is higher than the oil return outlet 11, and specifically, the height of the vertical partition 9 is set to be about one-half of the height of the fuel tank casing 1, so that the first compartment and the second compartment are connected to each other. . The hydraulic oil return oil enters the oil return chamber B through the oil return inlet 10, is filtered by the oil return filter assembly 4, and flows from the oil return outlet 11 into the second compartment. Since the height of the longitudinal partition 9 is higher than the oil return outlet 11, the hydraulic oil flowing out of the oil return outlet 11 does not directly enter the oil suction filter assembly 3, but first enters the second compartment for cooling and precipitation. The hydraulic oil in the upper part of the second compartment flows over the top of the longitudinal partition 9 into the first compartment, and is filtered by the oil suction filter assembly 3 and then discharged from the fuel tank. Of course, the pressure equalization device of the present invention is not limited to the above two types. For example, in an embodiment not shown, the pressure balance device may be disposed on top of the vertical wall 7 separating the oil suction chamber A and the oil return chamber B. One or more connected holes. Providing the communication hole not only balances the pressure in the oil suction chamber A and the oil return chamber B, thereby solving the technical problem of the present invention, and it is not necessary to add any equipment, which is advantageous for further cost saving. The aforementioned excavator fuel tank is suitable for use in various excavators, and is particularly suitable for use in large tonnage excavators. As can be seen from the above description, the above-described embodiments of the present invention achieve the following technical effects: Due to the action of the pressure balance device, the pressure difference between the oil suction chamber and the oil return chamber is very small or there is no pressure difference, so that the oil is returned. There is basically no residual hydraulic oil in the cavity. The volume of this hydraulic oil can be omitted. Under the condition that the excavator system requires the same flow of hydraulic oil, the hydraulic oil refueling amount and the excavator tank volume can be reduced accordingly. As a result, the amount of oil consumed and the consumables of the excavator tank are also reduced, saving production and operating costs. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

1. An excavator fuel tank, comprising:

a fuel tank case (1), comprising an oil suction chamber (A) and a return oil chamber (B); an oil suction filter assembly (3) located in the oil suction chamber (A);

An oil return filter assembly (4) located in the oil return chamber (B);

a first pre-pressure type air filter (2) disposed in the tank body (1) and communicating with the oil suction chamber (A);

The utility model further comprises: the excavator fuel tank further comprising:

A pressure equalizing device is disposed on the tank body (1) to balance the pressure of the oil suction chamber (A) and the oil return chamber (B).

2. The excavator fuel tank according to claim 1, wherein the pressure equalization device comprises a balance conduit (5) communicating the oil suction chamber (A) and the oil return chamber (B).

3. The excavator fuel tank according to claim 2, characterized in that both ends of the balance duct (5) are detachably connected to the top of the tank body (1), respectively.

4. The excavator fuel tank according to claim 1, wherein the pressure equalization device comprises a second pre-pressure type air filter (6) disposed on the fuel tank casing (1) and with the back The oil chamber (B) is connected.

The excavator fuel tank according to claim 1, wherein the fuel tank body (1) comprises: a vertical wall (7) disposed around the oil return filter assembly (4), welded to the a top plate and a side plate of the fuel tank case (1);

a transverse partition (8) at the bottom of the vertical wall (7), together with the vertical wall (7), the top plate and the side plates of the fuel tank casing (1), enclose the oil return chamber (B) .

6. The excavator fuel tank according to claim 5, wherein the pressure equalization device comprises a communication hole provided at a top of the vertical wall (7).

7. The excavator fuel tank according to claim 5, wherein

Providing a return oil inlet (10) for flowing hydraulic oil into the oil return chamber (B) on a side plate of the fuel tank body (1) surrounding the oil return chamber (B); An oil return outlet (11) for hydraulic oil to flow out of the oil return chamber (B) is provided on the diaphragm (8).

The excavator fuel tank according to any one of claims 1 to 7, wherein the fuel tank body

(1) comprising a vertical partition (9), the vertical partition (9) partitioning the interior of the tank body (1) into a first compartment and a second compartment that communicate with each other, the oil suction filter assembly ( 3) in the first compartment, an oil return outlet (11) for hydraulic oil flowing out of the oil return chamber (B) is located in the second compartment, communicating the first compartment and the second The communication portion of the compartment is higher than the oil return outlet (11).

An excavator comprising an excavator fuel tank, characterized in that the excavator fuel tank is the excavator fuel tank according to any one of claims 1 to 8.