WO2013078817A1

WO2013078817A1 - Engineering machine and flow distributing and converging hydraulic control system thereof

Info

Publication number: WO2013078817A1
Application number: PCT/CN2012/074240
Authority: WO
Inventors: 彭勇; 刘正雷; 易曦
Original assignee: 湖南三一智能控制设备有限公司; 三一汽车起重机械有限公司
Priority date: 2011-11-29
Filing date: 2012-04-18
Publication date: 2013-06-06
Also published as: CN102434519A; CN102434519B

Abstract

Disclosed in the present invention is a flow distributing and converging hydraulic control system for an engineering machine, which comprises: a first oil supplying pipeline and a second oil supplying pipeline communicated or disconnected through a flow distributing and converging valve (4); a first load feedback oil pipeline and a second load feedback oil pipeline respectively connected with a first oil inlet and a second oil inlet of a shuttle valve (2), wherein an oil outlet of the shuttle valve (2) is communicated with the second oil supplying pipeline through a second flow compensation valve (6); and a pressure stop valve (1), wherein the first load feedback oil pipeline is communicated or disconnected with the first oil inlet of the shuttle valve (2) through the pressure stop valve (1). Also disclosed in the present invention is the engineering machine, which comprises a vehicle loading portion adopting the above flow distributing and converging hydraulic control system. When a second working link is started prior to a first working link, the hydraulic control system can avoid the influence such as impact and vibration to the second working link caused by the first working link and so on.

Description

The invention relates to a Chinese patent which is submitted to the Chinese Patent Office on November 29, 2011, the application number is 201110387803.3, and the invention name is "an engineering machinery and its combined hydraulic control system" Priority of the application, the entire contents of which are incorporated herein by reference.

Technical field

The invention relates to the technical field of engineering machinery, in particular to a split flow hydraulic control system for engineering machinery. Furthermore, the invention relates to a construction machine comprising the above-described split flow hydraulic control system.

Background technique

A crane is a commonly used construction machine. Currently, in small and medium-sized cranes, two pumps are usually used to supply oil to the working oil circuit. Please refer to FIG. 1. FIG. 1 is a hydraulic schematic diagram of a split-flow hydraulic control system in the prior art; the lower cylinder introduces the defects existing in the working process of the split-flow hydraulic control system.

In the prior art, as shown in FIG. 1 , the split flow hydraulic control system includes a first oil supply path for supplying oil to the first working unit and a second oil supply path for supplying oil to the second working unit, and further includes a split flow. The valve 4 and the shuttle valve 2; the first oil supply passage and the second oil supply passage are connected or disconnected through the split valve 4; the hydraulic system further includes a first load feedback oil passage, a second load feedback oil passage, and a shuttle valve 2 The first load feedback oil path and the second load feedback oil path are respectively connected to the oil inlet a and the oil inlet b of the shuttle valve 2, and the oil outlet c of the shuttle valve 2 passes through the second flow compensation valve 6 and the second supply The oil passage is connected; the first load feedback oil passage is in communication with the first oil supply passage through the first flow compensation valve 5.

With the split-flow hydraulic control system, when the first working joint is operated separately and the second working joint is operated separately, the split-closing valve 4 can be set to be in the upper working position, and the first hydraulic pump and the second hydraulic pump are respectively the first The working joint and the second working joint are separately supplied with oil; it is also possible to set the splitting and closing valve 4 to be in the lower working position, so that the first hydraulic pump and the second hydraulic pump jointly supply oil for one work.

When the first work combination and the second work combination work are required, the split flow valve 4 is in the upper working position, and the first hydraulic pump and the second hydraulic pump respectively supply oil for the first work connection and the second work connection; Firstly starting the second working connection and restarting the first working connection, because the first load feedback oil path and the second load feedback oil path are simultaneously connected with the oil inlet a and the oil inlet b of the shuttle valve 2, the first load feedback pressure PL1 and the second load feedback pressure PL2 simultaneously act on the spool of the shuttle valve 2 in the opposite direction. The valve core will be shaken and a certain impact will occur, causing the second working link to be interfered by the first working connection, which seriously affects the composite operating performance of the hydraulic system.

In view of this, it is urgent to further optimize the existing split-flow hydraulic control system for the above technical problems, to avoid the impact when the first working joint and the second working joint are combined, and to improve the combined action of the split-flow hydraulic control system. Work stability and reliability.

Summary of the invention

The technical problem to be solved by the present invention is to provide a split-flow hydraulic control system for a construction machine, so as to avoid the impact of the first working connection and the first working connection when the composite operation is started, and the composite action is improved. Work stability and reliability. Another technical problem to be solved by the present invention is to provide a construction machine including the above-described split flow hydraulic control system.

In order to solve the above technical problems, the present invention provides a hydraulic control system for a construction machine, comprising:

a first oil supply passage and a second oil supply passage, which are connected or disconnected by a split valve;

The first load feedback oil path and the second load feedback oil path are respectively connected to the first oil inlet port and the second oil inlet port of the shuttle valve; the oil outlet of the shuttle valve passes through the second flow compensation valve and the Said second oil supply path is connected;

A pressure shut-off valve is also included, the first load feedback oil passage being in communication with or disconnected from the first oil inlet of the shuttle valve through the pressure shut-off valve.

Preferably, the pressure shut-off valve is a two-position three-way reversing valve, and in the first working position, the first load feedback oil passage is in communication with the first oil inlet of the shuttle valve; in the second working position, The first load feedback oil passage is disconnected from the first oil inlet of the shuttle valve.

Preferably, a check valve is further included, and an oil inlet of the one-way valve is connected to the second oil supply passage through the split flow valve, and an oil outlet of the one-way valve and the first oil supply port The road is connected.

Preferably, the one-way valve is a plug-in check valve.

Preferably, the split flow valve is a two-position two-way reversing valve, and in the first working position, the one-way valve oil inlet is in communication with the first oil supply passage; in the second working position, the single The oil inlet to the valve is disconnected from the first oil supply passage.

Preferably, a first flow compensation valve is further included, and the first load feedback oil passage is in communication with the first oil supply passage through the first flow compensation valve.

Preferably, the first flow compensation valve and the second flow compensation valve are both speed regulating valves. The invention provides a split flow hydraulic control system for a construction machine, comprising a pressure shut-off valve, wherein the first load feedback oil passage is connected or disconnected from the first oil inlet of the shuttle valve through a pressure shut-off valve.

With this loop, the size of PLmax determines the magnitude of the working pressure P2 of the second working unit. When the first working joint is operated separately, the second working joint has no action, and the second working combined load feedback pressure PL2 is small, close to OMPa, and at this time, the pressure shut-off valve is adjusted to make the first load feedback oil passage and the shuttle valve first. The oil inlet is connected, and the maximum load feedback pressure PLmax=Pl. At this time, the first oil supply passage and the second oil supply passage can be connected to each other to supply the first working oil supply by providing the split flow valve to communicate with the first oil supply passage and the second oil supply passage.

When the second working combination is separately operated and the first working joint has no action, the split flow valve may be set to open the first oil supply passage and the second oil supply passage, and the first hydraulic pump and the second hydraulic pump are respectively a working union and a second working unit are separately supplied with oil; at the same time, a pressure shut-off valve is provided to disconnect the first load feedback oil passage and the second load feedback oil passage, so that the load from the first oil inlet of the shuttle valve The feedback pressure is small, close to OMpa, at this time, therefore PLmax = P2.

It can be seen from the above working process that when the second working combination is operated alone, its working pressure P2 is only related to its own load feedback pressure PL2, and is independent of the first working load feedback pressure PL1. At this time, the first work linkage work is restarted, and the first load feedback pressure PL1 of the first work link does not affect the work of the second work link. It can be seen that the above-mentioned split-flow hydraulic control system can avoid the impact of impact and vibration caused by the first working joint on the second working joint when the second working joint is started first and then the first working joint is started, and the splitting flow is ensured. The stability and reliability of the hydraulic control system during compound operation.

The present invention also provides a construction machine including a boarding portion; the boarding portion employs a split flow hydraulic control system as described above.

Preferably, the construction machine is specifically a hydraulic crane.

Since the above-described split flow hydraulic control system has the above technical effects, the construction machine including the split flow hydraulic control system should also have the same technical effect, and will not be described herein.

DRAWINGS

1 is a hydraulic schematic diagram of a split flow hydraulic control system in the prior art;

2 is a hydraulic principle diagram of a specific embodiment of a split flow hydraulic system according to the present invention;

3 is a schematic structural view of a split flow hydraulic system provided by the present invention; Figure 4 is a BB arrow view of Figure 3.

The correspondence between the reference numerals in the figure and the part names is:

Pressure shut-off valve 1 ; shuttle valve 2; check valve 3; split valve 4; first flow compensating valve 5; second flow compensating valve 6.

detailed description

The core of the present invention is to provide a split flow hydraulic control system for a construction machine, which can avoid impact and vibration when the first work joint and the second work joint are combined, and improve the combined action of the split flow hydraulic control system. Time stability and reliability. Another core of the present invention is to provide a construction machine including the above-described split flow hydraulic control system.

In order to make those skilled in the art better understand the technical solutions of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

Please refer to FIG. 2 to FIG. 4 . FIG. 2 is a hydraulic schematic diagram of a specific embodiment of a split flow hydraulic system according to the present invention; FIG. 3 is a schematic structural view of a split flow hydraulic system provided by the present invention; The BB is in the view.

In a specific embodiment, as shown in FIG. 2 to FIG. 4, the split flow hydraulic control system provided by the present invention includes a first oil supply passage, a second oil supply passage, a first load feedback oil passage, and a second load. a feedback oil passage; the first oil supply passage and the second oil supply passage are connected or disconnected through the split valve 4; the first load feedback oil passage is connected or disconnected from the first oil inlet a of the shuttle valve 2 through the pressure shutoff valve 1 The second load feedback oil passage is in communication with the second oil inlet port b of the shuttle valve 2, and the oil outlet port c of the shuttle valve 2 is in communication with the second oil supply passage through the second flow rate compensating valve 6.

With this loop, as shown in Figure 2, the magnitude of PLmax determines the magnitude of the working pressure P2 of the second working association. When the first working combination is separately operated, the second working connection has no action, and the second working combined load feedback pressure PL2 is small, close to OMPa, and at this time, the pressure shut-off valve 1 is adjusted to make the first load feedback oil path and the shuttle valve 2 The first oil inlet is connected, and the maximum load feedback pressure PLmax=Pl. At this time, the first oil supply passage and the second oil supply passage can be connected to each other to supply the first working oil supply by connecting the split flow valve 4 to the first oil supply passage and the second oil supply passage.

When the second working unit is operated separately and the first working unit has no action, the split valve 4 can be set to open the first oil supply path and the second oil supply path, so that the first hydraulic pump and the second hydraulic pump are respectively The first working union and the second working coal are separately supplied with oil; at the same time, the pressure shut-off valve 1 is arranged to open the first load feedback oil passage and the second load feedback oil passage, so that the first oil inlet from the shuttle valve 2 Mouth The load feedback pressure is small, close to OMpa, at this time, so PLmax = P2.

Of course, the above specific embodiment does not limit the specific structural form of the pressure shut-off valve 1, nor does it define the specific structural form of the split flow valve 4. Where the pressure shut-off valve 1 is disposed between the first load feedback circuit and the shuttle valve 2, The split-flow hydraulic control system for ensuring that the first load feedback right path and the first oil inlet of the shuttle valve 2 are cut off when the second working unit is separately operated should fall within the protection range of the present invention.

It is also possible to further provide a specific structural form of the above-described pressure shutoff valve 1 and split flow valve 4. In a further aspect, the pressure shut-off valve 1 described above may be specifically a two-position three-way reversing valve. In the first working position, the first load feedback oil passage is in communication with the first oil inlet port a of the shuttle valve 2; in the second working position, the first load feedback oil passage is disconnected from the first oil inlet port a of the shuttle valve 2 . The two-position three-way reversing valve can realize the connection or disconnection of the first load feedback oil passage and the first oil port of the shuttle valve 2 in a single cylinder, thereby avoiding vibration and impact during the compound operation. Of course, the above-described pressure shut-off valve 1 is not limited to the above-mentioned two-position three-way reversing valve, and a two-way two-way reversing valve, a three-position four-way reversing valve, and the like may be used.

In another embodiment, the split flow hydraulic control system may further include a check valve 3, and the oil inlet of the check valve 3 is connected to the second oil supply passage through the split flow valve 4, and the check valve 3 is discharged. The oil port is in communication with the first oil supply passage. With this structure, the one-way flow of the split flow can be realized, further ensuring that the two oil sources of the first work joint and the second work joint are independent of each other, and the working stability of the split flow hydraulic control system is ensured. Further, the check valve 3 may be a plug-in check valve, and the plug-in can realize the installation and disassembly of the check valve 3. However, the one-way valve 3 can also adopt other mounting methods.

In another embodiment, the split valve 4 may be a two-position two-way reversing valve. In the first working position, the check valve 3 inlet port is in communication with the first oil supply passage; in the second working position. , The oil inlet of the check valve 3 is disconnected from the first oil supply passage. Thus, by switching the working position of the two-position two-way switching valve, the splitting or joining of the first oil supply passage and the second oil supply passage can be realized in a single cylinder. Of course, the above-mentioned split valve 4 can also adopt a reversing valve of other configurations, for example, a two-position three-way reversing valve or the like.

In a further aspect, the first load feedback oil passage is in communication with the first oil supply passage through the first flow compensation valve 5. With this configuration, when the first working connection is working, the first load feedback pressure PL1 is fed back to the first oil supply path via the first load feedback oil path and the first flow compensation valve 5, thereby establishing the first working pressure P1. The closed loop connection of the first working connection can be realized, and the working stability and reliability of the split flow hydraulic control system are ensured.

Further, the first flow compensating valve 5 and the second flow compensating valve 6 described above may each be a regulating valve. The speed control valve is a pressure compensated throttle valve that can achieve flow compensation. Of course, the above two flow compensating valves may also employ a flow compensating valve of other configurations such as an overflow throttle valve.

The present invention also provides a construction machine including a boarding portion; the boarding portion can employ a split flow hydraulic control system as described above.

Since the above-described split flow hydraulic control system has the above technical effects, the construction machine including the split flow hydraulic control system should also have corresponding technical effects.

Specifically, the above construction machine may be a hydraulic crane. Of course, the above-mentioned split-flow hydraulic control system is applicable to other construction machinery, such as concrete pump trucks, in addition to hydraulic cranes.

The above is a description of a split flow hydraulic control system and engineering including the same provided by the present invention. The above description of the embodiments is merely for assisting in understanding the method of the present invention and its core idea. It should be noted that those skilled in the art can make various modifications and changes to the present invention without departing from the spirit and scope of the invention.

Claims

Rights request

1. A split-flow hydraulic control system for construction machinery, comprising:

a first oil supply passage and a second oil supply passage, which are connected or disconnected by a split valve (4); a first load feedback oil passage and a second load feedback oil passage, respectively, and the shuttle valve (2) The first oil inlet and the second oil inlet are connected; the oil outlet of the shuttle valve (2) is connected to the second oil supply passage through the second flow compensation valve (6); and the method further includes:

The pressure shut-off valve (1), the first load feedback oil passage is connected or disconnected from the first oil inlet of the shuttle valve (2) through the pressure shut-off valve (1).

2. The split-flow hydraulic control system for a construction machine according to claim 1, wherein the pressure shut-off valve (1) is a two-position three-way reversing valve, and in the first working position, the a load feedback oil passage is connected to the first oil inlet of the shuttle valve (2); in the second working position, the first load feedback oil passage is disconnected from the first oil inlet of the shuttle valve (2) open.

3. The split flow hydraulic control system for a construction machine according to claim 1, further comprising a one-way valve (3), the oil inlet of the one-way valve (3) passing through the split flow The valve (4) is connected to the second oil supply passage, and an oil outlet of the check valve (3) is in communication with the first oil supply passage.

A split flow hydraulic pressure control system for a construction machine according to claim 3, wherein said one-way valve (3) is a plug-in check valve.

The split flow hydraulic control system for a construction machine according to any one of claims 1 to 4, characterized in that the split flow valve (4) is a two-position two-way reversing valve, in the first work Position, the check valve (3) oil inlet is in communication with the first oil supply passage; in the second working position, the oil inlet of the one-way valve (3) is disconnected from the first oil supply passage open.

The split flow hydraulic control system for a construction machine according to any one of claims 1 to 4, further comprising a first flow compensating valve (5), wherein the first load feedback oil passage passes through The first flow compensating valve (5) is in communication with the first oil supply passage.

The split flow hydraulic control system for a construction machine according to claim 6, wherein the first flow compensation valve (5) and the second flow compensation valve (6) are speed control valves .

8. A construction machine comprising a boarding portion; wherein the boarding portion employs a split flow hydraulic control system according to any of claims 1-7. A construction machine according to claim 8, characterized in that it is specifically a hydraulic crane.