Throttling speed regulation hydraulic system

Abstract

The invention relates to the technical field of hydraulic regulation, and discloses a throttling speed regulation hydraulic system which is characterized in that the hydraulic flow is controlled through a speed regulation valve, and the controlled hydraulic flow flows to a first balance valve and a second balance valve through a first three-position four-way electromagnetic valve and a second three-position four-way electromagnetic valve respectively; and forward and reverse rotation of the walking hydraulic motors on the corresponding sides can be controlled through the first three-position four-way electromagnetic valve and the second three-position four-way electromagnetic valve, so that synchronism and control precision of the hydraulic walking motors are guaranteed, and system stability is improved.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic regulation, and in particular to a throttling speed regulating hydraulic system. Background Art

[0002] By designing the hydraulic system of a special lifting equipment vehicle, it is necessary to be able to effectively transmit the power of the motor to each operating component. This mainly includes being able to control the travel hydraulic motor at different speeds, being able to achieve straight and turning travel of the crawler chassis, being able to control the extension and retraction of the outrigger lifting hydraulic cylinder, and being able to control the speed of the slewing mechanism output motor under load.

[0003] According to the operating conditions of the special lifting equipment vehicle and the design requirements, the hydraulic system needs to adopt an open system. The current hydraulic system is difficult to ensure the synchronization and control accuracy of the hydraulic travel motor during the throttling speed regulation process, which easily leads to system instability. Summary of the invention

[0004] In view of this, the present invention provides a throttling speed regulation hydraulic system, which solves the technical problem that the current hydraulic system is difficult to ensure the synchronization and control accuracy of the hydraulic travel motor during the throttling speed regulation process, which easily leads to system instability.

[0005] The present invention provides a throttling speed regulating hydraulic system, comprising: a first oil tank, a first hydraulic pump, a first speed regulating valve, a first travel hydraulic motor, a second travel hydraulic motor, a first three-position four-way solenoid valve, a second three-position four-way solenoid valve, a first check valve, a second check valve, a first balancing valve and a second balancing valve;

[0006] The first oil tank is in communication with the first hydraulic pump;

[0007] The first hydraulic pump is in communication with the first speed regulating valve;

[0008] The first speed regulating valve is respectively connected to the first three-position four-way solenoid valve, the second three-position four-way solenoid valve, the first one-way valve and the second one-way valve;

[0009] The first three-position four-way solenoid valve is connected to the first balancing valve;

[0010] The first balance valve is connected to the first end of the first travel hydraulic motor;

[0011] The first one-way valve is connected to the second end of the first travel hydraulic motor;

[0012] The second three-position four-way solenoid valve is connected to the second balancing valve;

[0013] The second balance valve is connected to the first end of the second travel hydraulic motor;

[0014] The second one-way valve is connected to the second end of the first travel hydraulic motor.

[0015] Preferably, the system further comprises: a first filter connected to a pipeline between the first oil tank and the first hydraulic pump.

[0016] Preferably, a first electromagnetic overflow valve is further provided between the first hydraulic pump and the first speed regulating valve.

[0017] Preferably, the first one-way valve is connected to the first travel hydraulic motor through two paths, wherein the two paths are respectively connected to a third one-way valve and a fourth one-way valve;

[0018] The second one-way valve is connected to the second travel hydraulic motor through two paths, wherein the two paths are respectively connected to a fifth one-way valve and a sixth one-way valve.

[0019] Preferably, the system further comprises: a second oil tank, wherein the second oil tank is respectively connected to the first three-position four-way solenoid valve and the second three-position four-way solenoid valve.

[0020] Preferably, the system further comprises: a third three-position four-way solenoid valve, a fourth three-position four-way solenoid valve, a first hydraulically controlled lifting leg unit and a second hydraulically controlled lifting leg unit;

[0021] The first hydraulic pump is connected to the third three-position four-way solenoid valve and the fourth three-position four-way solenoid valve respectively;

[0022] The third three-position four-way solenoid valve is connected to the first hydraulically controlled lifting leg unit;

[0023] The fourth three-position four-way solenoid valve is connected to the second hydraulically controlled lifting leg unit.

[0024] Preferably, a second electromagnetic overflow valve is provided on the pipeline between the first hydraulic pump and the third three-position four-way solenoid valve and the fourth three-position four-way solenoid valve.

[0025] Preferably, the first hydraulically controlled lifting leg unit and the second hydraulically controlled lifting leg unit each comprise two sets of parallel hydraulically controlled leg modules;

[0026] The hydraulically controlled outrigger module comprises a hydraulically controlled one-way valve and an outrigger lifting hydraulic cylinder, and the hydraulically controlled one-way valve is connected to the outrigger lifting hydraulic cylinder.

[0027] Preferably, the third three-position four-way solenoid valve and the fourth three-position four-way solenoid valve are connected to a third oil tank and a fourth oil tank respectively.

[0028] Preferably, the system further comprises: a fifth oil tank, a second filter, a second hydraulic pump, a two-position four-way solenoid valve, a second speed regulating valve and a rotary mechanism hydraulic motor;

[0029] The fifth oil tank is in communication with the second filter;

[0030] The second filter is in communication with the second hydraulic pump;

[0031] The second hydraulic pump is connected to the two-position four-way solenoid valve;

[0032] The two-position four-way solenoid valve is connected to the second speed regulating valve;

[0033] The second speed regulating valve is connected to the first end of the rotary mechanism hydraulic motor, and the second end of the rotary mechanism hydraulic motor is connected to the two-position four-way solenoid valve;

[0034] A third electromagnetic overflow valve is also provided on the pipeline between the second filter and the second hydraulic pump.

[0035] It can be seen from the above technical solutions that the present invention has the following advantages:

[0036] The throttling speed-regulating hydraulic system provided in the embodiment of the present application controls the hydraulic flow through a speed-regulating valve, and the controlled hydraulic flow flows to the first balancing valve and the second balancing valve through the first three-position four-way solenoid valve and the second three-position four-way solenoid valve respectively, and the forward and reverse rotation of the travel hydraulic motor on the corresponding side can be controlled through the first three-position four-way solenoid valve and the second three-position four-way solenoid valve, thereby ensuring the synchronization and control accuracy of the hydraulic travel motor and improving the stability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 A schematic structural diagram of a throttling speed regulating hydraulic system provided by an embodiment of the present invention;

[0038] Figure 2 A schematic diagram of the hydraulic control structure of the slewing mechanism provided in an embodiment of the present invention;

[0039] Figure 3 The simulation result of no-load straight-line forward movement provided by the embodiment of the present invention;

[0040] Figure 4 The simulation result of the eccentric load straight-line forward movement provided by the embodiment of the present invention;

[0041] Figure 5 The leg lifting simulation result provided by the embodiment of the present invention;

[0042] Figure 6 The simulation results of the counterclockwise rotation of the boom rotation mechanism provided in the embodiment of the present invention. DETAILED DESCRIPTION

[0043] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] The throttling speed regulating hydraulic system provided in the embodiment of the present application can be applied to operating mechanical equipment such as a lifting equipment vehicle, and the lifting equipment vehicle includes two walking devices, two lifting legs and a slewing mechanism.

[0045] like Figure 1 As shown, a throttling speed regulating hydraulic system provided in an embodiment of the present application includes: a first oil tank 11, a first hydraulic pump 21, a first speed regulating valve 31, a first travel hydraulic motor 61, a second travel hydraulic motor 62, a first three-position four-way solenoid valve 41, a second three-position four-way solenoid valve 42, a first one-way valve 71, a second one-way valve 72, a first balancing valve 51 and a second balancing valve 52;

[0046] The first oil tank 11 is connected to the first hydraulic pump 21;

[0047] The first hydraulic pump 21 is connected to the first speed regulating valve 31;

[0048] The first speed regulating valve 31 is respectively connected to the first three-position four-way solenoid valve 41, the second three-position four-way solenoid valve 42, the first one-way valve 71 and the second one-way valve 72;

[0049] The first three-position four-way solenoid valve 41 is connected to the first balancing valve 51;

[0050] The first balance valve 51 is connected to the first end of the first travel hydraulic motor 61;

[0051] The first one-way valve 71 is connected to the second end of the first travel hydraulic motor 61;

[0052] The second three-position four-way solenoid valve 42 is connected to the second balancing valve 52;

[0053] The second balance valve 52 is connected to the first end of the second travel hydraulic motor 62;

[0054] The second one-way valve 72 is connected to the second end of the first travel hydraulic motor 61 .

[0055] It is understandable that the speed of the travel hydraulic motor is related to the oil flow provided by the hydraulic system. If the motor speed needs to be reduced, the purpose can be achieved by reducing the oil flow of the hydraulic system. Conversely, increasing the oil flow can increase the motor speed.

[0056] Among them, the first three-position four-way solenoid valve 41, the first balancing valve 51 and the first travel hydraulic motor 61 constitute the driving component of the travel hydraulic motor driven by the first travel hydraulic motor 61, and the second three-position four-way solenoid valve 42, the second balancing valve 52 and the second travel hydraulic motor 62 constitute the driving component of the travel hydraulic motor driven by the second travel hydraulic motor 62. The structures of the two driving components are symmetrically arranged to ensure that the flow rate is relatively balanced and stable.

[0057] In practical applications, the speed control valve is a valve that can control flow and pressure. By adjusting the opening of the speed control valve, the flow and pressure of the hydraulic system can be changed to achieve speed regulation. The flow cross-sectional area of ​​the first speed control valve 31 can be adjusted by selecting a suitable flow value according to actual needs, thereby changing the flux area to adjust the flow until the set flow value is reached. At the same time, during the adjustment process, it is necessary to continuously monitor the changes in system pressure or flow and make adjustments in time. In the three-position four-way solenoid valve, the T port is connected to the oil tank, the oil outlet of the speed control valve 8 is connected to the P port of the three-position four-way solenoid valve 1, and the A port and the B port are connected to the balancing valve. By using the balancing valve, the chassis is guaranteed to have good stability when driving on a slope.

[0058] It should be noted that the working principle of this system is:

[0059] The hydraulic flow is controlled by the first speed regulating valve 31, and the controlled hydraulic flow flows to the first balancing valve 51 and the second balancing valve 52 through the first three-position four-way solenoid valve 41 and the second three-position four-way solenoid valve 42 respectively. Among them, the first three-position four-way solenoid valve 41 and the second three-position four-way solenoid valve 42 can control the forward and reverse rotation of the travel hydraulic motor on the corresponding side, thereby realizing the forward, backward, steering and other working states of the crawler chassis. The balancing valve can make the chassis have good stability when traveling on slopes.

[0060] It should be noted that the throttling speed-regulating hydraulic system provided in the embodiment of the present application controls the hydraulic flow through a speed regulating valve, and the controlled hydraulic flow flows through the first three-position four-way solenoid valve 41 and the second three-position four-way solenoid valve 42 to the first balancing valve 51 and the second balancing valve 52 respectively, and the first three-position four-way solenoid valve 41 and the second three-position four-way solenoid valve 42 can control the forward and reverse rotation of the travel hydraulic motor on the corresponding side, thereby ensuring the synchronization and control accuracy of the hydraulic travel motor and improving the system stability.

[0061] In some embodiments, the system further includes a first filter 81, which is connected to a pipeline between the first oil tank 11 and the first hydraulic pump 21, so as to filter the oil in the oil tank to ensure the safety of the system.

[0062] In some embodiments, in order to ensure the safety of the system, a first electromagnetic overflow valve 33 is further provided between the first hydraulic pump 21 and the first speed regulating valve 31, so as to protect the hydraulic system from overload damage by controlling the flow and pressure of the system, while also controlling the speed stability and accuracy of the system.

[0063] In some embodiments, the first one-way valve 71 is connected to the first travel hydraulic motor 61 through two paths, wherein the two paths are respectively connected to a third one-way valve 73 and a fourth one-way valve 74;

[0064] The second one-way valve 72 is connected to the second travel hydraulic motor 62 through two paths, wherein the two paths are respectively connected to a fifth one-way valve and a sixth one-way valve.

[0065] It can be understood that the forward and reverse rotation of the travel hydraulic motor on the corresponding side is controlled by controlling the three-position four-way solenoid valve through the two-way one-way valve externally connected to the travel hydraulic motor.

[0066] In some embodiments, the system further includes: a second oil tank 12, and the second oil tank 12 is connected to the first three-position four-way solenoid valve 41 and the second three-position four-way solenoid valve 42 respectively.

[0067] It is understandable that when the oil flow controlled by the speed control valve is insufficient to support actual demand, the second oil tank can be used in conjunction with the three-position four-way solenoid valve to achieve drive control of the travel hydraulic motor.

[0068] like Figure 1 As shown, the system also controls the lifting of the hydraulically controlled lifting legs, wherein the system further comprises: a third three-position four-way solenoid valve 43, a fourth three-position four-way solenoid valve 44, a first hydraulically controlled lifting leg unit and a second hydraulically controlled lifting leg unit;

[0069] The first hydraulic pump 21 is connected to the third three-position four-way solenoid valve 43 and the fourth three-position four-way solenoid valve 44 respectively;

[0070] The third three-position four-way solenoid valve 43 is connected to the first hydraulically controlled lifting leg unit;

[0071] The fourth three-position four-way solenoid valve 44 is connected to the second hydraulically controlled lifting leg unit.

[0072] In some embodiments, a second electromagnetic relief valve 34 is provided on the pipelines between the first hydraulic pump 21 and the third three-position four-way electromagnetic valve 43 and the fourth three-position four-way electromagnetic valve 44 .

[0073] The first hydraulically controlled lifting leg unit and the second hydraulically controlled lifting leg unit each include two sets of parallel hydraulically controlled leg modules;

[0074] The hydraulically controlled outrigger module includes a hydraulically controlled one-way valve 91 and an outrigger lifting hydraulic cylinder 92 , and the hydraulically controlled one-way valve 91 and the outrigger lifting hydraulic cylinder 92 are connected.

[0075] The third three-position four-way solenoid valve 43 and the fourth three-position four-way solenoid valve 44 are connected to the third oil tank 13 and the fourth oil tank 14 respectively.

[0076] It should be noted that the oil outlet of the first hydraulic pump 21 is connected to the P port of the three-position four-way solenoid valve, and the T port of the three-position four-way solenoid valve is connected to the oil tank. The extension and retraction of the outrigger lifting hydraulic cylinder is adjusted by controlling the three-position four-way solenoid valve. The hydraulically controlled one-way valve is connected to the oil circuit of the lower chamber of the hydraulic cylinder to prevent the piston and slider of the hydraulic cylinder and other active parts from sliding down due to leakage of the slide valve. When the reversing valve is in the middle position, the two hydraulically controlled one-way valves are closed, tightly sealing the oil in the two chambers of the hydraulic cylinder so that the piston cannot move due to external force. When the piston of the hydraulic cylinder retreats, the pressure oil is controlled to open the hydraulically controlled one-way valve, and the oil in the right chamber can be discharged smoothly. The first hydraulic pump 21, the three-position four-way solenoid valve, the lifting hydraulic cylinder and the hydraulically controlled one-way valve constitute the outrigger lifting system. By controlling the three-position four-way solenoid valve, the hydraulic oil can flow into or out of the hydraulic cylinder, thereby controlling the lifting of the outrigger.

[0077] In some embodiments, Figure 2 The hydraulic control structure of the slewing mechanism shown in the embodiment of the present application also controls the slewing mechanism. Specifically, the system further includes: a fifth oil tank 15, a second filter 82, a second hydraulic pump 22, a two-position four-way solenoid valve 45, a second speed regulating valve 32 and a slewing mechanism hydraulic motor 63;

[0078] The fifth oil tank 15 is in communication with the second filter 82;

[0079] The second filter 82 is in communication with the second hydraulic pump 22;

[0080] The second hydraulic pump 22 is connected to a two-position four-way solenoid valve 45;

[0081] The two-position four-way solenoid valve 45 is connected to the second speed regulating valve 32;

[0082] The second speed regulating valve 32 is connected to a first end of the rotary mechanism hydraulic motor 63, and a second end of the rotary mechanism hydraulic motor 63 is connected to a two-position four-way solenoid valve 45;

[0083] A third electromagnetic relief valve 35 is further provided on the pipeline between the second filter 82 and the second hydraulic pump 22 .

[0084] It should be noted that the second hydraulic pump 22, the two-position four-way solenoid valve 45, the second speed control valve 32 and the slewing mechanism hydraulic motor 63 constitute a power output system. The two-position four-way solenoid valve 45 can control the switch of the power output system, and the second speed control valve 32 can adjust the speed of the slewing mechanism hydraulic motor 63.

[0085] In order to prove the control effectiveness of the throttling speed regulation hydraulic system provided in the embodiment of the present application, the embodiment of the present application also models the throttling speed regulation hydraulic system provided in the embodiment of the present application based on the AMESim software, and uses the AMESim simulation software to model the hydraulic system and establish mathematical models of various hydraulic components.

[0086] According to the hydraulic system schematic diagram of the special lifting equipment vehicle, the corresponding component model is called from the AMESim software model library to establish a hydraulic system simulation model.

[0087] The commonly used HM46 hydraulic oil is used in the hydraulic simulation system, and the displacement of the hydraulic pump is 100 mL / r. The displacement of the travel hydraulic motor is 100 mL / r. The displacement of the power output hydraulic motor is 195 mL / r. The relief valve set pressure is 12 MPa and 24 MPa respectively. The telescopic displacement of the hydraulic cylinder is set to 0.3m. The hydraulic pipeline adopts the system default mode. The rated speed of the motor is 2000 r / min.

[0088] Analysis of straight-line walking conditions: When the electric crawler chassis is traveling without load, the forces between the crawlers on both sides and the ground are consistent. According to the analysis of crawler chassis walking dynamics in Section 2, it can be calculated that the torque borne by the left and right crawler motors is 50N·m. The chassis moves forward in a straight line from 2 to 18 seconds. The simulation results are shown in Figure 2. Figure 3 As shown in the figure, the simulation results show that the speeds of the crawler motors on the left and right sides are consistent and the synchronization is good.

[0089] When the crawler chassis is in operation or on the road, the center position of the chassis changes due to different ground resistance or loading heavy objects. In order to explore the linear motion of the chassis under uneven load or different road resistance, the torque of the left and right motors is set to 50 N·m and 80 N·m respectively, and the forward simulation analysis of the chassis is carried out. The simulation results are shown in Figure 2. Figure 4 As shown in the simulation curve, when the torques of the hydraulic motors on both sides are different, the hydraulic motor with smaller torque will have a higher speed, and the absolute value of the speed difference is 4.6% of the average speed. The motors on both sides are not greatly affected by the torque change, and the linearity of the crawler chassis during walking operation is relatively stable.

[0090] Analysis of leg lifting working conditions:

[0091] Under the outrigger lifting condition, a thrust of 5000 N is applied to the piston rod of the hydraulic cylinder along the rod direction. 0-20s is set as the straight-line forward stage of the special hoisting equipment, the outrigger lifting mechanism remains unchanged, 20-34s is set as the outrigger extension stage, and 34-40s is set as the outrigger retraction stage. From the simulation results Figure 5 It can be seen that the speed of the outrigger is stable during the lifting stage, and there is no vibration when the piston rod moves to the dead point. The synchronization of the piston rods of the hydraulic cylinders on both sides is good, which meets the requirements of the outrigger lifting.

[0092] Outrigger lifting

[0093] Analysis of boom swing working condition: Under the boom swing working condition, considering the main working load swing resistance torque M borne by the swing mechanism SW , which is composed as follows:

[0094] M SW =M f +M s +M w +M p +M Q

[0095] Where M f M is the friction resistance torque of the slewing bearing device; s M is the rotation resistance torque caused by the tilt of the rotary platform; w is the resistance moment caused by wind pressure; M p M is the rotation resistance torque caused by the rotation start; Q It is the rotational resistance torque caused by the sway of the load.

[0096] Therefore, considering the influence of the rotation resistance torque, a torque of 6000 N·m is applied to the reducer along the axial direction during the simulation. The boom rotation mechanism is kept unchanged from 0 to 2s, and 2 to 18s is set as the counterclockwise rotation stage of the boom rotation mechanism. Figure 6 It can be seen that the speed of the boom slewing mechanism is stable during the counterclockwise slewing stage.

[0097] Through AMEsim simulation analysis, it can be seen that the simulation results of the system provided in the embodiment of the present application can meet the design requirements, that is, the driving scheme of the hydraulic system can be determined.

[0098] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a system or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0099] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A throttling speed regulating hydraulic system, characterized in that: include: A first oil tank, a first hydraulic pump, a first speed regulating valve, a first travel hydraulic motor, a second travel hydraulic motor, a first three-position four-way solenoid valve, a second three-position four-way solenoid valve, a first check valve, a second check valve, a first balancing valve, and a second balancing valve; The first oil tank is in communication with the first hydraulic pump; The first hydraulic pump is in communication with the first speed regulating valve; The first speed regulating valve is respectively connected to the first three-position four-way solenoid valve, the second three-position four-way solenoid valve, the first one-way valve and the second one-way valve; The first three-position four-way solenoid valve is connected to the first balancing valve; The first balance valve is connected to the first end of the first travel hydraulic motor; The first one-way valve is connected to the second end of the first travel hydraulic motor; The second three-position four-way solenoid valve is connected to the second balancing valve; The second balance valve is connected to the first end of the second travel hydraulic motor; The second one-way valve is connected to the second end of the first travel hydraulic motor.

2. The throttling speed regulating hydraulic system according to claim 1, characterized in that: Also includes: A first filter is connected to a pipeline between the first oil tank and the first hydraulic pump.

3. The throttling speed regulating hydraulic system according to claim 1, characterized in that: A first electromagnetic overflow valve is also provided between the first hydraulic pump and the first speed regulating valve.

4. The throttling speed regulating hydraulic system according to claim 1, characterized in that: The first one-way valve is connected to the first travel hydraulic motor through two paths, wherein the two paths are respectively connected to a third one-way valve and a fourth one-way valve; The second one-way valve is connected to the second travel hydraulic motor through two paths, wherein the two paths are respectively connected to a fifth one-way valve and a sixth one-way valve.

5. The throttling speed regulating hydraulic system according to claim 1, characterized in that: Also includes: A second oil tank, wherein the second oil tank is connected to the first three-position four-way solenoid valve and the second three-position four-way solenoid valve respectively.

6. The throttling speed regulating hydraulic system according to claim 1, characterized in that: Also includes: a third three-position four-way solenoid valve, a fourth three-position four-way solenoid valve, a first hydraulically controlled lifting leg unit, and a second hydraulically controlled lifting leg unit; The first hydraulic pump is connected to the third three-position four-way solenoid valve and the fourth three-position four-way solenoid valve respectively; The third three-position four-way solenoid valve is connected to the first hydraulically controlled lifting leg unit; The fourth three-position four-way solenoid valve is connected to the second hydraulically controlled lifting leg unit.

7. The throttling speed regulating hydraulic system according to claim 6, characterized in that: A second electromagnetic overflow valve is provided on the pipelines between the first hydraulic pump and the third three-position four-way electromagnetic valve and the fourth three-position four-way electromagnetic valve.

8. The throttling speed regulating hydraulic system according to claim 6, characterized in that: The first hydraulically controlled lifting leg unit and the second hydraulically controlled lifting leg unit each comprise two sets of parallel hydraulically controlled leg modules; The hydraulically controlled outrigger module comprises a hydraulically controlled one-way valve and an outrigger lifting hydraulic cylinder, and the hydraulically controlled one-way valve is connected to the outrigger lifting hydraulic cylinder.

9. The throttling speed regulating hydraulic system according to claim 6, characterized in that: The third three-position four-way solenoid valve and the fourth three-position four-way solenoid valve are connected to the third oil tank and the fourth oil tank respectively.

10. The throttling speed regulating hydraulic system according to claim 1, characterized in that: Also includes: a fifth oil tank, a second filter, a second hydraulic pump, a two-position four-way solenoid valve, a second speed regulating valve and a rotary mechanism hydraulic motor; The fifth oil tank is in communication with the second filter; The second filter is in communication with the second hydraulic pump; The second hydraulic pump is connected to the two-position four-way solenoid valve; The two-position four-way solenoid valve is connected to the second speed regulating valve; The second speed regulating valve is connected to the first end of the rotary mechanism hydraulic motor, and the second end of the rotary mechanism hydraulic motor is connected to the two-position four-way solenoid valve; A third electromagnetic overflow valve is also provided on the pipeline between the second filter and the second hydraulic pump.

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