Supporting leg hydraulic system and engineering machinery

Abstract

A landing leg hydraulic system comprises a control valve bank, a horizontal oil cylinder, a vertical oil cylinder and a safety valve, and the control valve bank is provided with an oil inlet P, an oil return port T, a first oil port A1, a second oil port B1 and a third oil port A2; the oil inlet P is communicated to a main oil way, and the oil return port T is communicated to an oil return way; the first oil port A1 is communicated to a rod cavity of the horizontal oil cylinder, the second oil port B1 is communicated to a rodless cavity of the horizontal oil cylinder, the third oil port A2 is communicated to a rodless cavity of the vertical oil cylinder through a first oil way, and the fourth oil port B2 is communicated to a rod cavity of the vertical oil cylinder through a second oil way. The two-way hydraulic lock comprises a first hydraulic control one-way valve and a second hydraulic control one-way valve, the first hydraulic control one-way valve is arranged on the first oil way, the second hydraulic control one-way valve is arranged on the second oil way, and an oil inlet of the safety valve is communicated to the oil way between the second hydraulic control one-way valve and the rod cavity of the vertical oil cylinder. The landing leg hydraulic system can improve the safety performance of the whole machine. The invention further relates to engineering machinery with the landing leg hydraulic system.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering machinery, and in particular to an outrigger hydraulic system and an engineering machinery having the outrigger hydraulic system. Background Art

[0002] With the advancement of national production and construction, construction machinery, especially large-scale construction machinery, plays an increasingly important role in national production and life. The safety performance of large-scale construction machinery has always been one of the most important indicators for measuring construction machinery, and the safety performance of the outrigger system, which plays a vital role in the working stability of construction machinery, is particularly important. The main function of the outrigger is to provide a stable and flat support surface, so that the outrigger of the construction machinery can firmly support the entire machinery on various complex terrains and ground. For example: on unstable ground such as soft soil, mud, sand, etc., the outrigger can effectively disperse the pressure of the outrigger on the ground to prevent the machinery from sinking or tilting; on hard ground such as concrete, stone slabs, etc., the outrigger can provide sufficient friction to prevent the machinery from sliding or moving during work. In addition to the basic support function, the outrigger also has the functions of improving construction safety, reducing vehicle damage, and reducing maintenance costs.

[0003] Outriggers can be roughly divided into three categories: fixed outriggers, deployable outriggers and hydraulic outriggers. Hydraulic outriggers use the liquid pressure of hydraulic oil to adjust the height and stabilize mechanical equipment, making the mechanical equipment more stable and precise in different construction scenarios. Therefore, they are widely used in various construction machinery.

[0004] At present, the outrigger hydraulic system of engineering machinery on the market uses high-pressure cylinders as actuators. High-pressure cylinders have the advantages of reliable performance and high energy transfer density. The outrigger system generally includes four outriggers: left front, right front, left and right, and right rear. Each outrigger in the outrigger hydraulic system is equipped with a horizontal cylinder and a vertical cylinder. The function of the horizontal cylinder is to extend and retract the outrigger. After the outrigger is extended, the vertical cylinder is used to support the engineering machinery off the ground for lifting. Because the vertical cylinder has to bear the weight of the engineering machinery and the load during the lifting process, under special working conditions, the vertical cylinder is very likely to have a "cylinder expansion" failure, that is, the rod chamber of the vertical cylinder is too high due to pressure, resulting in cylinder deformation, leakage and other failures. At the same time, the pressure of the hydraulic oil in the pipeline connected to the rodless chamber and the rod chamber of the vertical cylinder also increases accordingly, which will also cause other components in the oil circuit to lose control or be damaged. Similarly, this failure will also occur in the horizontal cylinder, and there are hidden dangers in the safety performance of the outrigger hydraulic system. Summary of the invention

[0005] In view of this, the present invention provides an outrigger hydraulic system and an engineering machinery having the outrigger hydraulic system, which can greatly ensure the safety and reliability of the outrigger hydraulic system, thereby improving the safety performance of the entire machine.

[0006] The outrigger hydraulic system provided by the embodiment of the present invention includes a control valve group, a horizontal oil cylinder, a vertical oil cylinder, a safety valve and a two-way hydraulic lock, the control valve group has an oil inlet P, an oil return port T, a first oil port A1, a second oil port B1, and a third oil port A2; the oil inlet P is connected to the main oil circuit, and the oil return port T is connected to the return oil circuit; the first oil port A1 is connected to the rod chamber of the horizontal oil cylinder, the second oil port B1 is connected to the rodless chamber of the horizontal oil cylinder, the third oil port A2 is connected to the rodless chamber of the vertical oil cylinder through the first oil circuit, and the fourth oil port B2 is connected to the rod chamber of the vertical oil cylinder through the second oil circuit; the two-way hydraulic lock includes a first hydraulically controlled one-way valve and a second hydraulically controlled one-way valve, the first hydraulically controlled one-way valve is arranged on the first oil circuit, the second hydraulically controlled one-way valve is arranged on the second oil circuit, the oil inlet of the safety valve is connected to the oil circuit between the second hydraulically controlled one-way valve and the rod chamber of the vertical oil cylinder, and the oil outlet of the safety valve is connected to the return oil circuit.

[0007] Furthermore, the safety valve is a pressure relief valve.

[0008] Furthermore, it also includes a first pressure sensor and a second pressure sensor, the first pressure sensor is used to monitor the hydraulic oil pressure of the rod chamber of the vertical cylinder, and the second pressure sensor is used to monitor the hydraulic oil pressure of the rodless chamber of the vertical cylinder, and the outrigger hydraulic system stops working when the hydraulic oil pressure of the rod chamber of the vertical cylinder exceeds a first set value and / or the hydraulic oil pressure of the rodless chamber of the vertical cylinder exceeds a second set value.

[0009] Furthermore, the first set value and the second set value are both smaller than the setting value of the safety valve.

[0010] Furthermore, it also includes a third pressure sensor and a fourth pressure sensor, the third pressure sensor is used to monitor the hydraulic oil pressure of the rod chamber of the horizontal cylinder, and the fourth pressure sensor is used to monitor the hydraulic oil pressure of the rodless chamber of the horizontal cylinder; the outrigger hydraulic system stops working when the hydraulic oil pressure of the rod chamber of the horizontal cylinder exceeds a third set value and / or the hydraulic oil pressure of the rodless chamber of the horizontal cylinder exceeds a fourth set value.

[0011] Furthermore, it also includes a PLC controller, and the first pressure sensor, the second pressure sensor, the third pressure sensor and the fourth pressure sensor are all connected to the PLC controller, and the PLC controller is used to receive the hydraulic oil pressure signals monitored by the first pressure sensor, the second pressure sensor, the third pressure sensor and the fourth pressure sensor and control whether the outrigger hydraulic system stops working according to the received hydraulic oil pressure signals.

[0012] Further, the control valve group includes a first control valve and a second control valve, the first oil port A1 and the second oil port B1 of the control valve group are two working oil ports of the first control valve, the third oil port A2 and the fourth oil port B2 of the control valve group are two working oil ports of the second control valve; the oil inlet P of the control valve group is respectively connected to the oil inlet of the first control valve and the oil inlet of the second control valve, and the oil return port T of the control valve group is respectively connected to the oil return port of the first control valve and the oil return port of the second control valve.

[0013] Further, the first control valve has a first working state and a second working state. When the first control valve is in the first working state, the oil inlet P is connected to the second oil port B1, and the first oil port A1 is connected to the oil return port T. When the first control valve is in the second working state, the oil inlet P is connected to the first oil port A1, and the second oil port B1 is connected to the oil return port T. The second control valve has a first working state and a second working state. When the second control valve is in the first working state, the oil inlet P is connected to the fourth oil port B2, and the third oil port A2 is connected to the oil return port T. When the second control valve is in the second working state, the oil inlet P is connected to the third oil port A2, and the fourth oil port B2 is connected to the oil return port T.

[0014] Furthermore, the outrigger hydraulic system also includes a first quick connector and a second quick connector, wherein the first quick connector is arranged on the oil circuit where the oil inlet P of the control valve group is connected to the main oil circuit, and the second quick connector is arranged on the oil circuit where the oil return port T of the control valve group is connected to the return oil circuit.

[0015] The present invention also provides an engineering machine, comprising the above-mentioned outrigger hydraulic system.

[0016] In summary, the outrigger hydraulic system of the present invention controls a valve group, a horizontal oil cylinder, a vertical oil cylinder, a safety valve and a two-way hydraulic lock, and the control valve group has an oil inlet P, an oil return port T, a first oil port A1, a second oil port B1 and a third oil port A2; the oil inlet P is connected to the main oil circuit, and the oil return port T is connected to the return oil circuit; the first oil port A1 is connected to the rod chamber of the horizontal oil cylinder, the second oil port B1 is connected to the rodless chamber of the horizontal oil cylinder, the third oil port A2 is connected to the rodless chamber of the vertical oil cylinder through the first oil circuit, and the fourth oil port B2 is connected to the rod chamber of the vertical oil cylinder through the second oil circuit; the two-way hydraulic lock includes a first hydraulically controlled one-way valve and a second hydraulically controlled one-way valve, the first hydraulically controlled one-way valve is arranged on the first oil circuit, the second hydraulically controlled one-way valve is arranged on the second oil circuit, the oil inlet of the safety valve is connected to the oil circuit between the second hydraulically controlled one-way valve and the rod chamber of the vertical oil cylinder, and the oil outlet of the safety valve is connected to the return oil circuit. By setting a safety valve on the oil circuit connected to the rod chamber of the vertical oil cylinder, the safety valve is integrated on one side of the two-way hydraulic lock and close to one end of the rod chamber of the vertical oil cylinder. When the pressure of the hydraulic oil in the rod chamber of the vertical oil cylinder exceeds the set value of the safety valve, the safety valve releases pressure, effectively avoiding failures such as "cylinder expansion" and "internal leakage" caused by the formation of a booster cylinder effect in the vertical oil cylinder, thereby greatly improving the safety performance of the entire machine.

[0017] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the outrigger hydraulic system of a preferred embodiment of the present invention.

[0019] Figure 2 yes Figure 1 The outrigger pressure signal control strategy of the outrigger hydraulic system when a blockage occurs is shown. DETAILED DESCRIPTION

[0020] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the present invention is described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0021] Figure 1 This is a schematic diagram of the outrigger hydraulic system of a preferred embodiment of the present invention. Figure 1The outrigger hydraulic system of the present invention comprises a control valve group 20, a horizontal oil cylinder 30, a vertical oil cylinder 40 and a safety valve 50. The control valve group 20 has an oil inlet P, an oil return port T, a first oil port A1, a second oil port B1 and a third oil port A2; the oil inlet P is connected to the main oil circuit, and the oil return port T is connected to the oil return circuit; the first oil port A1 is connected to the rod chamber of the horizontal oil cylinder 30, the second oil port B1 is connected to the rodless chamber of the horizontal oil cylinder 30, the third oil port A2 is connected to the rodless chamber of the vertical oil cylinder 40 through the first oil circuit 101, and the fourth oil port B2 is connected to the rod chamber of the vertical oil cylinder 40 through the second oil circuit 102. The two-way hydraulic lock 60 includes a first hydraulically controlled one-way valve 61 and a second hydraulically controlled one-way valve 62. The first hydraulically controlled one-way valve 61 is arranged on the first oil circuit 101, and the second hydraulically controlled one-way valve 62 is arranged on the second oil circuit 102. The oil inlet of the safety valve 50 is connected to the oil circuit between the second hydraulically controlled one-way valve 62 and the rod chamber of the vertical oil cylinder 40, and the oil outlet of the safety valve 50 is connected to the oil circuit or the oil tank. Preferably, the safety valve 50 is a pressure relief valve.

[0022] The main oil circuit provides hydraulic oil to the outrigger hydraulic system for controlling the operation of various components in the outrigger hydraulic system, including the oil tank, main pump, etc. The return oil circuit is used to return the hydraulic oil to the oil tank for reuse. When the outrigger hydraulic system is blocked and the outrigger hydraulic system cannot return oil, high pressure will be formed in the rod chamber of the vertical cylinder 40. The present invention sets a safety valve 50 on the oil circuit connected to the rod chamber of the vertical cylinder 40, and integrates the safety valve 50 on one side of the two-way hydraulic lock 60 and close to one end of the rod chamber of the vertical cylinder 40. When the pressure of the hydraulic oil in the rod chamber of the vertical cylinder 40 exceeds the setting value of the safety valve 50 (that is, the maximum pressure value that the safety valve can withstand), the safety valve 50 releases pressure, which effectively avoids the vertical cylinder 40 from "cylinder expansion" and "internal leakage" due to the formation of a booster cylinder effect, thereby greatly improving the safety performance of the whole machine.

[0023] Furthermore, the outrigger hydraulic system further includes a first pressure sensor 71 and a second pressure sensor 72, wherein the first pressure sensor 71 is used to monitor the hydraulic oil pressure of the rod chamber of the vertical oil cylinder 40, and the second pressure sensor 72 is used to monitor the hydraulic oil pressure of the rodless chamber of the vertical oil cylinder 40. The outrigger hydraulic system stops working when the hydraulic oil pressure of the rod chamber of the vertical oil cylinder 40 exceeds a first set value and / or the hydraulic oil pressure of the rodless chamber of the vertical oil cylinder 40 exceeds a second set value, that is, when the first pressure sensor 71 monitors that the hydraulic oil pressure of the rod chamber of the vertical oil cylinder 40 exceeds the first set value and / or the second pressure sensor 72 monitors that the hydraulic oil pressure of the rodless chamber of the vertical oil cylinder 40 exceeds the second set value, the outrigger hydraulic system stops working, thereby protecting the vertical oil cylinder 40. The first set value and the second set value can be adjusted accordingly according to the type of engineering machinery used by the outrigger hydraulic system, and are not limited here. When the outrigger hydraulic system is provided with the safety valve 50, the first pressure sensor 71 and the second pressure sensor 72 at the same time, the vertical cylinder 40 can be doubly protected to prevent the rod chamber of the vertical cylinder 40 from being damaged due to excessive pressure of the hydraulic oil.

[0024] Further, the first setting value and the second setting value are smaller than the setting value of the safety valve 50 .

[0025] Since the horizontal cylinder 30 will also have the same problem as the vertical cylinder 40, the outrigger hydraulic system also includes a third pressure sensor 73 and a fourth pressure sensor 74. The third pressure sensor 73 is used to monitor the hydraulic oil pressure of the rod chamber of the horizontal cylinder 30, and the fourth pressure sensor 74 is used to monitor the hydraulic oil pressure of the rodless chamber of the horizontal cylinder 30. The outrigger hydraulic system stops working when the hydraulic oil pressure of the rod chamber of the horizontal cylinder 30 exceeds the third set value and / or the hydraulic oil pressure of the rodless chamber of the horizontal cylinder 40 exceeds the fourth set value, that is, when it is monitored that the hydraulic oil pressure of the rod chamber of the horizontal cylinder 30 exceeds the third set value and / or the hydraulic oil pressure of the rodless chamber of the horizontal cylinder 40 exceeds the fourth set value, the outrigger hydraulic system is controlled to stop working. The third set value and the fourth set value can be adjusted accordingly according to the type of engineering machinery used by the outrigger hydraulic system, and are not limited here. A third pressure sensor 73 and a fourth pressure sensor 74 are added to the rod chamber and the rodless chamber of the horizontal cylinder 30. When the horizontal cylinder 30 is working, the pressure values ​​of the hydraulic oil in the rod chamber and the rodless chamber of the horizontal cylinder 30 are monitored simultaneously to protect the horizontal cylinder 30 from damage due to excessive pressure of the hydraulic oil.

[0026] Figure 2 yes Figure 1 For the outrigger pressure signal control strategy of the outrigger hydraulic system shown in FIG. Figure 2The outrigger hydraulic system also includes a PLC controller 80, and the first pressure sensor 71, the second pressure sensor 72, the third pressure sensor 73 and the fourth pressure sensor 74 are all connected to the PLC controller 80. The PLC controller 80 is used to receive the hydraulic oil pressure signals monitored by the first pressure sensor 71, the second pressure sensor 72, the third pressure sensor 73 and the fourth pressure sensor 74 and control whether the outrigger hydraulic system stops working according to the received hydraulic oil pressure signals.

[0027] The prior art only sets a pressure sensor in the rodless chamber of the vertical oil cylinder or in the oil circuit connected to the rodless chamber of the vertical oil cylinder to monitor the pressure of the hydraulic oil. The processing method of the PLC controller is relatively simple. If the pressure sensor fails at the same time when the outrigger hydraulic system is blocked, the control strategy also fails accordingly, which poses a safety hazard. The present invention sets pressure monitoring points in the rodless chamber and rod chamber of the horizontal oil cylinder 30 and the rodless chamber and rod chamber of the vertical oil cylinder 40 at the same time, and the pressure signal of the outrigger hydraulic system is increased to 4 monitoring points. When any pressure signal is abnormal, the outrigger hydraulic system can unload or stop working, thereby greatly improving the safety performance of the whole machine.

[0028] In this embodiment, the control valve group 20 includes a first control valve 21 and a second control valve 22. The first oil port A1 and the second oil port B1 of the control valve group 20 are two working oil ports of the first control valve 21, and the third oil port A2 and the fourth oil port B2 of the control valve group 20 are two working oil ports of the second control valve 22; the oil inlet P of the control valve group 20 is respectively connected to the oil inlet of the first control valve 21 and the oil inlet of the second control valve 22, and the oil return port T of the control valve group 20 is respectively connected to the oil return port of the first control valve 21 and the oil return port of the second control valve 22.

[0029] Further, the first control valve 21 and the second control valve 22. The first control valve 21 has a first working state and a second working state. When the first control valve 21 is in the first working state, the oil inlet P is connected to the second oil port B1, and the first oil port A1 is connected to the oil return port T. When the first control valve 21 is in the second working state, the oil inlet P is connected to the first oil port A1, and the second oil port B1 is connected to the oil return port T; the second control valve 22 has a first working state and a second working state. When the second control valve 22 is in the first working state, the oil inlet P is connected to the fourth oil port B2, and the third oil port A2 is connected to the oil return port T. When the second control valve 22 is in the second working state, the oil inlet P is connected to the third oil port A2, and the fourth oil port B2 is connected to the oil return port T.

[0030] Furthermore, the first control valve 21 and the second control valve 22 are both three-position four-way electromagnetic reversing valves, which can be controlled to be in the corresponding working state by controlling the electromagnets at both ends to be energized. For example, when the left electromagnet of the first control valve 21 is energized, the left position of the first control valve 21 works, and the first control valve 21 is outside the first working state, and when the right electromagnet of the first control valve 21 is energized, the right position of the first control valve 21 works, and the first control valve 21 is outside the second working state.

[0031] Furthermore, the first control valve 21 also includes a third working state. When the first control valve 21 is in the third working state, the oil inlet P, the oil return port T, the first oil port A1 and the second oil port B1 are disconnected from each other. The second control valve 21 also includes a third working state. When the second control valve 22 is in the third working state, the oil inlet P is disconnected, and the third oil port A2 and the fourth oil port B2 are both connected to the oil return port T.

[0032] Due to transportation requirements, construction machinery, especially large-scale construction machinery, outriggers and other parts are widely connected to the main hydraulic system by quick-change joints for convenient transportation. A quick-change joint is a joint that can connect or disconnect the pipeline without tools. The quick-change joint has a male end and a female end. When the male end and the female end are assembled together, the hydraulic pipeline can be connected. The purpose of quickly disconnecting the hydraulic pipeline can be achieved by releasing the male end and the female end. In this embodiment, the outrigger hydraulic system also includes a first quick joint 91 and a second quick joint 92. The first quick joint 91 is arranged on the oil inlet P of the control valve group 20 connected to the oil circuit of the main oil circuit, and the second quick joint 92 is arranged on the oil return port T of the control valve group 20 connected to the oil circuit of the return oil circuit. When the second quick joint 92 is blocked, the hydraulic oil pressure in the second oil circuit 102 and the rod chamber of the vertical oil cylinder 40 will increase rapidly. Of course, the reason for the increase in hydraulic oil pressure is not limited to this. When other components have problems, the oil circuit may also be blocked, resulting in an increase in hydraulic oil pressure.

[0033] The present invention also relates to an engineering machine, comprising the above-mentioned outrigger hydraulic system. Other structures of the engineering machine are well known to those skilled in the art and will not be described in detail here.

[0034] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A hydraulic system for an outrigger, comprising a control valve group (20), a horizontal cylinder (30) and a vertical cylinder (40), characterized in that: The control valve group (20) further comprises a safety valve (50) and a two-way hydraulic lock (60). The control valve group (20) comprises an oil inlet P, an oil return port T, a first oil port A1, a second oil port B1, and a third oil port A2. The oil inlet P is connected to the main oil circuit, and the oil return port T is connected to the oil return circuit. The first oil port A1 is connected to the rod chamber of the horizontal oil cylinder (30), the second oil port B1 is connected to the rodless chamber of the horizontal oil cylinder (30), the third oil port A2 is connected to the rodless chamber of the vertical oil cylinder (40) through the first oil circuit (101), and the fourth oil port B2 is connected to the rodless chamber of the vertical oil cylinder (40) through the second The oil circuit (102) is connected to the rod chamber of the vertical oil cylinder (40); the bidirectional hydraulic lock (60) includes a first hydraulically controlled one-way valve (61) and a second hydraulically controlled one-way valve (62), the first hydraulically controlled one-way valve (61) is arranged on the first oil circuit (101), and the second hydraulically controlled one-way valve (62) is arranged on the second oil circuit (102); the oil inlet of the safety valve (50) is connected to the oil circuit between the second hydraulically controlled one-way valve (62) and the rod chamber of the vertical oil cylinder (40), and the oil outlet of the safety valve (50) is connected to the return oil circuit.

2. The outrigger hydraulic system according to claim 1, characterized in that: The safety valve (50) is a pressure relief valve.

3. The outrigger hydraulic system according to claim 2, characterized in that: It also includes a first pressure sensor (71) and a second pressure sensor (72), wherein the first pressure sensor (71) is used to monitor the hydraulic oil pressure of the rod chamber of the vertical cylinder (40), and the second pressure sensor (72) is used to monitor the hydraulic oil pressure of the rodless chamber of the vertical cylinder (40), and the outrigger hydraulic system stops working when the hydraulic oil pressure of the rod chamber of the vertical cylinder (40) exceeds a first set value and / or the hydraulic oil pressure of the rodless chamber of the vertical cylinder (40) exceeds a second set value.

4. The outrigger hydraulic system according to claim 3, characterized in that: The first set value and the second set value are both smaller than the setting value of the safety valve (50).

5. The outrigger hydraulic system according to claim 3, characterized in that: It also includes a third pressure sensor (73) and a fourth pressure sensor (74), wherein the third pressure sensor (73) is used to monitor the hydraulic oil pressure of the rod chamber of the horizontal cylinder (30), and the fourth pressure sensor (74) is used to monitor the hydraulic oil pressure of the rodless chamber of the horizontal cylinder (30); the outrigger hydraulic system stops working when the hydraulic oil pressure of the rod chamber of the horizontal cylinder (30) exceeds a third set value and / or the hydraulic oil pressure of the rodless chamber of the horizontal cylinder (40) exceeds a fourth set value.

6. The outrigger hydraulic system according to claim 5, characterized in that: It also includes a PLC controller (80), the first pressure sensor (71), the second pressure sensor (72), the third pressure sensor (73) and the fourth pressure sensor (74) are all connected to the PLC controller (80), and the PLC controller (80) is used to receive the hydraulic oil pressure signals monitored by the first pressure sensor (71), the second pressure sensor (72), the third pressure sensor (73) and the fourth pressure sensor (74) and control whether the outrigger hydraulic system stops working according to the received hydraulic oil pressure signals.

7. The outrigger hydraulic system according to claim 1, characterized in that: The control valve group (20) comprises a first control valve (21) and a second control valve (22); the first oil port A1 and the second oil port B1 of the control valve group (20) are two working oil ports of the first control valve (21); the third oil port A2 and the fourth oil port B2 of the control valve group (20) are two working oil ports of the second control valve (22); the oil inlet P of the control valve group (20) is respectively connected to the oil inlet of the first control valve (21) and the oil inlet of the second control valve (22); the oil return port T of the control valve group (20) is respectively connected to the oil return port of the first control valve (21) and the oil return port of the second control valve (22).

8. The outrigger hydraulic system according to claim 7, characterized in that: The first control valve (21) has a first working state and a second working state. When the first control valve (21) is in the first working state, the oil inlet P is connected to the second oil port B1, and the first oil port A1 is connected to the oil return port T. When the first control valve (21) is in the second working state, the oil inlet P is connected to the first oil port A1, and the second oil port B1 is connected to the oil return port T. The second control valve (22) has a first working state and a second working state. When the second control valve (22) is in the first working state, the oil inlet P is connected to the fourth oil port B2, and the third oil port A2 is connected to the oil return port T. When the second control valve (22) is in the second working state, the oil inlet P is connected to the third oil port A2, and the fourth oil port B2 is connected to the oil return port T.

9. The outrigger hydraulic system according to claim 7, characterized in that: The outrigger hydraulic system further comprises a first quick connector (91) and a second quick connector (92), wherein the first quick connector (91) is arranged on an oil circuit connected to an oil inlet P of the control valve group (20) and a main oil circuit, and the second quick connector (92) is arranged on an oil return port T of the control valve group (20) and a return oil circuit connected to the oil return circuit.

10. An engineering machine, characterized in that: The invention comprises the outrigger hydraulic system as claimed in any one of claims 1 to 9.

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