阅读说明：本技术 一种充液系统及工程机械 (Liquid filling system and engineering machinery ) 是由 张立彬 李海军 赵华 秦慧卿 王国佐 于 2020-06-30 设计创作，主要内容包括：本发明涉及液压系统技术领域,尤其涉及一种充液系统及工程机械。充液系统包括：工作泵；储能器；充液阀块,包括第一进油口、第二进油口、第一出油口和第二出油口,第一进油口与工作泵的出油口连通,第一出油口同时与储能器的进出油口连通,第一出油口与第二进油口连通；充液阀块的先导油口与储能器的出油口连通,能够使第一进油口与第一出油口通断且第二进油口与第二出油口通断；梭阀；当工作泵为负载敏感泵或齿轮泵时,梭阀与第二出油口连通或断开。由于梭阀能够在不同类型泵使用时,选择性地与第二出油口连通或断开,因此不论是负载敏感泵还是齿轮泵,均可采用该充液系统对储能器进行充液,提高了该充液系统的通用性。(The invention relates to the technical field of hydraulic systems, in particular to a liquid filling system and engineering machinery. The liquid filling system comprises: a working pump; an energy storage device; the liquid filling valve block comprises a first oil inlet, a second oil inlet, a first oil outlet and a second oil outlet, the first oil inlet is communicated with the oil outlet of the working pump, the first oil outlet is simultaneously communicated with the oil inlet and the oil outlet of the energy accumulator, and the first oil outlet is communicated with the second oil inlet; a pilot oil port of the liquid filling valve block is communicated with an oil outlet of the energy accumulator, so that a first oil inlet and a first oil outlet can be connected and disconnected, and a second oil inlet and a second oil outlet can be connected and disconnected; a shuttle valve; and when the working pump is a load-sensitive pump or a gear pump, the shuttle valve is communicated or disconnected with the second oil outlet. The shuttle valve can be selectively communicated or disconnected with the second oil outlet when different types of pumps are used, so that the energy storage device can be charged by the charging system no matter a load-sensitive pump or a gear pump, and the universality of the charging system is improved.)

1. A fluid filling system, comprising:

a working pump (1) communicating with a working valve of a load to provide oil to the load;

an accumulator (2) for storing oil and providing oil for braking or pilot control;

the liquid filling valve block (3) comprises a first oil inlet (31), a second oil inlet (32), a first oil outlet (33) and a second oil outlet (34), the first oil inlet (31) is communicated with the oil outlet of the working pump (1), the first oil outlet (33) is simultaneously communicated with the oil inlet and the oil outlet of the energy accumulator (2), and the first oil outlet (33) is communicated with the second oil inlet (32);

a pilot oil port of the liquid filling valve block (3) is communicated with a liquid outlet of a liquid reservoir (2), and the first oil inlet (31) can be selectively communicated with the first oil outlet (33) and the second oil inlet (32) is communicated with the second oil outlet (34), or the first oil inlet (31) is disconnected with the first oil outlet (33) and the second oil inlet (32) is disconnected with the second oil outlet (34);

a shuttle valve (4);

when the working pump (1) is a load-sensitive pump, two oil inlets of the shuttle valve (4) are respectively communicated with a feedback oil port of the working pump and the second oil outlet (34), and an oil outlet of the shuttle valve (4) is communicated with a feedback oil port of the working pump (1);

when the working pump (1) is a gear pump, the shuttle valve (4) is disconnected with the second oil outlet (34).

2. The filling system according to claim 1, wherein the first oil inlet (31) is communicable with the first oil outlet (33) via a first throttle valve (5).

3. The filling system according to claim 1, wherein the second oil inlet (32) is communicable with the second oil outlet (34) through a second throttle (6).

4. The liquid filled system according to claim 1, wherein the first oil outlet (33) communicates with the accumulator (2) through a first one-way valve (7).

5. The liquid filling system according to claim 3, wherein the second throttle (6) communicates with the second oil outlet (34) through a second one-way valve (8).

6. The filling system according to claim 1, wherein a return spring (35) is provided on the filling valve block (3).

7. The filling system according to claim 6, wherein the pilot port of the filling valve block (3) and the return spring (35) are located on the same side, and the return spring (35) is a tension spring.

8. The filling system according to claim 6, wherein the pilot port of the filling valve block (3) and the return spring (35) are located on both sides of the valve block, and the return spring (35) is a compression spring.

9. The filling system according to claim 1, characterized in that the energy accumulator (2) communicates with a tank (9) via a relief valve.

10. A working machine comprising a charging system according to any one of claims 1-9.

Technical Field

The invention relates to the technical field of hydraulic systems, in particular to a liquid filling system and engineering machinery.

Background

In the existing hydraulic system, a gear pump is mostly adopted to charge an energy accumulator, the set pressure of the energy accumulator is set by a pilot overflow valve, when the pressure of the energy accumulator reaches a set value, the pilot overflow valve is opened, and the oil discharged from the gear pump directly returns to an oil tank for unloading or enters other execution structures. However, the existing liquid filling valve block can only be applied to a hydraulic system with a gear pump, and cannot be directly applied to a load sensitive system.

Therefore, a liquid filling system is needed to solve the above technical problems.

Disclosure of Invention

The invention aims to provide a liquid filling system and engineering machinery, which can be applied to a load sensitive system and a gear pump hydraulic system and have simpler structures.

In order to achieve the purpose, the invention adopts the following technical scheme:

there is provided a charging system comprising:

a working pump in communication with a working valve of a load to provide oil to the load;

the energy accumulator is used for storing oil and providing the oil for braking or pilot control;

the liquid filling valve block comprises a first oil inlet, a second oil inlet, a first oil outlet and a second oil outlet, the first oil inlet is communicated with the oil outlet of the working pump, the first oil outlet is simultaneously communicated with the oil inlet and the oil outlet of the energy accumulator, and the first oil outlet is communicated with the second oil inlet;

a pilot oil port of the liquid filling valve block is communicated with a liquid outlet of a liquid storage device, and the first oil inlet can be selectively communicated with the first oil outlet and the second oil inlet is communicated with the second oil outlet, or the first oil inlet is disconnected from the first oil outlet and the second oil inlet is disconnected from the second oil outlet;

a shuttle valve;

when the working pump is a load sensitive pump, two oil inlets of the shuttle valve are respectively communicated with a feedback oil port of the working pump and the second oil outlet, and an oil outlet of the shuttle valve is communicated with a feedback oil port of the working pump;

and when the working pump is a gear pump, the shuttle valve is disconnected with the second oil outlet.

As a preferable technical solution of the above liquid filling system, the first oil inlet may be communicated with the first oil outlet through a first throttle valve.

As a preferable technical solution of the above liquid filling system, the second oil inlet may be communicated with the second oil outlet through a second throttle valve.

As a preferable technical solution of the above liquid charging system, the first oil outlet is communicated with the accumulator through a first one-way valve.

As a preferable technical solution of the above liquid charging system, the second throttle valve is communicated with the second oil outlet through a second one-way valve.

As a preferable technical solution of the above liquid filling system, the liquid filling valve block is provided with a return spring.

As a preferred technical solution of the above-mentioned liquid filling system, the pilot oil port of the liquid filling valve block and the return spring are located on the same side of the liquid filling valve block, and the return spring is a tension spring.

As a preferred technical scheme of the above liquid filling system, the pilot oil port of the liquid filling valve block and the return spring are located at two sides of the liquid filling valve block, and the return spring is a compression spring.

As a preferable technical scheme of the liquid filling system, the energy accumulator is communicated with the oil tank through an overflow valve.

The invention also provides engineering machinery comprising the liquid charging system.

The invention has the beneficial effects that:

according to the liquid filling system provided by the invention, the shuttle valve can be selectively communicated or disconnected with the second oil outlet when different types of pumps are used, so that the working pump, no matter being a load sensitive pump or a gear pump, can adopt the liquid filling system provided by the invention to fill the energy storage device, and the universality of the liquid filling system is improved. It is not necessary to design different charging systems separately for different types of pumps.

Drawings

Fig. 1 is a schematic structural diagram of a liquid filling system according to an embodiment of the present invention.

In the figure:

1. a working pump; 2. an energy storage device; 3. a liquid filling valve block; 31. a first oil inlet; 32. a second oil inlet; 33. a first oil outlet; 34. a second oil outlet; 35. a return spring; 4. a shuttle valve; 5. a first throttle valve; 6. a second throttle valve; 7. a first check valve; 8. a second one-way valve; 9. and an oil tank.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

As shown in fig. 1, the present embodiment provides a charging system, which has a wide application range and is suitable for charging the energy storage device 2 with a load-sensitive pump and a gear pump. The liquid filling system comprises: the device comprises a working pump 1, an energy accumulator 2, a liquid filling valve block 3 and a shuttle valve 4. The working pump 1 is communicated with a working valve of a load to provide oil for the load, and the energy accumulator 2 is used for storing the oil and providing the oil for braking or pilot control; the liquid filling valve block 3 comprises a first oil inlet 31, a second oil inlet 32, a first oil outlet 33 and a second oil outlet 34, the first oil inlet 31 is communicated with an oil outlet of the working pump 1, the first oil outlet 33 is simultaneously communicated with an oil inlet and an oil outlet of the energy storage device 2 and an oil inlet of the first actuator, and the first oil outlet 33 is communicated with the second oil inlet 32; a pilot oil port of the liquid filling valve block 3 is communicated with an oil outlet of the liquid reservoir 2, and the first oil inlet 31 can be selectively communicated with the first oil outlet 33 and the second oil inlet 32 is communicated with the second oil outlet 34, or the first oil inlet 31 can be disconnected from the first oil outlet 33 and the second oil inlet 32 is disconnected from the second oil outlet 34; when the working pump 1 is a load-sensitive pump, two oil inlets of the shuttle valve 4 are respectively communicated with a feedback oil port of the working pump and a second oil outlet 34, and an oil outlet of the shuttle valve 4 is communicated with a feedback oil port of the working pump 1; when working pump 1 is a gear pump, shuttle valve 4 is communicated with or disconnected from second oil outlet 34.

In the liquid charging system provided in this embodiment, since the shuttle valve 4 can be selectively connected to or disconnected from the second oil outlet 34 when different types of pumps are used, the working pump 1, whether being a load-sensitive pump or a gear pump, can charge the energy storage device 2 by using the liquid charging system provided in this embodiment, thereby improving the versatility of the liquid charging system. It is not necessary to design different charging systems separately for different types of pumps.

Alternatively, in order to ensure the pressure of the oil to be stable and prevent the pressure of the oil entering the accumulator 2 from being too high, the first oil inlet 31 can communicate with the first oil outlet 33 through the first throttle valve 5 in this embodiment.

Optionally, in this embodiment, the second oil inlet 32 can communicate with the second oil outlet 34 through the second throttle 6 to perform the function of throttling and pressure reducing.

Alternatively, in the present embodiment, the first oil outlet 33 communicates with the accumulator 2 through the first check valve 7. The first check valve 7 can prevent oil in the energy accumulator 2 from flowing into the liquid filling valve block 3, and the oil in the energy accumulator 2 is effectively utilized.

Alternatively, in the present embodiment, second throttle 6 communicates with second oil outlet 34 through second check valve 8. Second check valve 8 will prevent backflow of oil from second outlet port 34.

In order to reset the valve core, a return spring 35 is further disposed on the liquid filling valve block 3 in this embodiment, and optionally, when the return spring 35 is a tension spring, the pilot port of the liquid filling valve block 3 and the return spring 35 are located on the same side of the liquid filling valve block 3. When the return spring 35 is a compression spring, the pilot oil port of the liquid filling valve block 3 and the return spring 35 are located on two sides of the liquid filling valve block 3.

In order to prevent the oil pressure of the accumulator from being too high, the accumulator can be communicated with the hydraulic oil tank 9 through an overflow valve, and the opening pressure of the overflow valve is the maximum working pressure of the accumulator.

The working state of the liquid charging system is described by taking the working pump 1 as a load-sensitive pump as an example.

The load sensitive pump is driven by a power source, when an engine or a motor is started, if a load and a brake or pilot control (namely an execution element) do not act, the load sensitive pump is in a low-displacement standby pressure state, pressure oil enters the liquid filling valve block 3 through the first oil inlet 31, at the moment, the valve core is in a left position, the pressure oil reaches the first one-way valve 7 through the first throttle valve 5, meanwhile, the pressure oil reaches the shuttle valve 4 through the second throttle valve 6 and the second one-way valve 8 and the second oil outlet 34 (namely an LS1 oil port), and due to the fact that LS2 has no pressure temporarily, the pressure oil from the second oil outlet 34 is fed back to the load sensitive pump as an LS signal, and the displacement of the pump is increased. The pressurized oil enters the accumulator 2 through the first check valve 7 to charge the accumulator 2.

The set pressure of the accumulator 2 is set by the reset spring 35 on the left side of the valve core, after the accumulator 2 finishes filling, pressure oil enters the right side of the valve core, the valve core is pushed leftwards, at the moment, the valve core works on the right position, and filling is finished. The first oil inlet and the second oil outlet 34 (i.e., the LS1 oil port) are in a closed state, and the displacement and the pressure of the load-sensitive pump are reduced to a standby state.

The accumulator 2 provides an oil source for braking or pilot control through the Psp port, when the internal pressure of the accumulator 2 is reduced to the set value of the reset spring 35, the liquid filling valve block 3 works at the left position to fill liquid, and the operation is repeated, so that the pressure of the accumulator 2 is maintained in a certain range, and a sufficient oil source is provided for the system.

The embodiment provides a construction machine, which comprises a liquid charging system provided in the embodiment. The liquid charging system uses different working pumps 1 and has a simple structure.

In addition, the foregoing is only the preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.