Hydraulic system with all execution parts decoupled and excavator

Abstract

The invention relates to the technical field of excavators, and particularly discloses a hydraulic system with all execution parts decoupled and an excavator, the hydraulic system with all execution parts decoupled comprises an oil supplementing pump, a first movable arm oil pump, a movable arm balance valve, a first bucket rod oil pump, a bucket rod balance valve, a first bucket oil pump and a bucket balance valve, the first movable arm oil pump and two cavities of the movable arm oil cylinder form a movable arm hydraulic loop, the first bucket rod oil pump and two cavities of the bucket rod oil cylinder form a bucket rod hydraulic loop, the first bucket oil pump and two cavities of the bucket oil cylinder form a bucket hydraulic loop, and the movable arm balance valve is used for communicating a pipeline on the side, with small pressure, in the movable arm hydraulic loop with an oil supplementing oil way. The bucket rod balance valve is used for communicating a pipeline on the side with small pressure in the bucket rod hydraulic loop with the oil supplementing oil way to balance the oil temperature of the bucket rod hydraulic loop, and the bucket balance valve is used for communicating a pipeline on the side with small pressure in the bucket hydraulic loop with the oil supplementing oil way to balance the oil temperature of the bucket hydraulic loop.

Description

Technical Field

[0001] The present invention relates to the technical field of excavators, and in particular to a hydraulic system and an excavator with completely decoupled actuators. Background Art

[0002] The main movements of the hydraulic excavator include the movement of the whole machine (left movement, right movement), platform rotation, and the movement of the boom, dipper arm and bucket of the working device. The main movement performance of the hydraulic excavator includes excavation performance, loading performance, leveling performance, etc., which requires a good coordination relationship between the various movements, that is, controllability.

[0003] In the prior art, such as the previous patent with application number CN202410833273.8, a networked electro-hydraulic drive system is disclosed, which supplies oil to all actuators through independent oil sources to achieve complete decoupling of each circuit, eliminating the energy waste caused by load coupling when multiple actuators of the excavator perform compound actions, and can improve operability. However, the open pumps used in each circuit control the movement speed and direction of the oil cylinder through a multi-way reversing valve, which will cause a large impact on the system action. The negative load energy is completely lost by the heat generated by the multi-way valve interception, and energy recovery cannot be achieved, resulting in low operating efficiency of the hydraulic system.

[0004] In this regard, the prior art also provides a closed hydraulic system, which connects the rod chamber and the rodless chamber of the oil cylinder through an oil pump to realize the flow of oil in the two chambers. At the same time, an accumulator is also configured to compensate for the flow difference between the rod chamber and the rodless chamber and recover part of the energy. However, the accumulator will overflow at high pressure when the maximum pressure is reached, which will cause power loss; in addition, the high-pressure overflow will generate a lot of heat and affect the thermal balance of the system. In order to avoid excessive oil temperature in the system, additional temperature monitoring is required. When the temperature is abnormal, the hot oil in the system will overflow to the oil tank through the low-pressure overflow valve, and the oil in the oil tank will be replenished into the system, which will affect the normal operation of the oil cylinder. Summary of the invention

[0005] The object of the present invention is to provide a hydraulic system and an excavator with all actuators decoupled, so as to decouple each actuator to improve operability and optimize the thermal balance of the system.

[0006] On the one hand, the present invention provides a hydraulic system with fully decoupled actuators, the hydraulic system with fully decoupled actuators comprising a boom cylinder, an arm cylinder and a bucket cylinder, the boom cylinder comprising a boom rod chamber and a boom rodless chamber with variable volumes, the arm cylinder comprising an arm rod chamber and an arm rodless chamber with variable volumes, the bucket cylinder comprising a bucket rod chamber and a bucket rodless chamber with variable volumes, the hydraulic system with fully decoupled actuators further comprising:

[0007] An oil replenishment pump, one end of which is connected to the oil tank and the other end is connected to the oil replenishment circuit;

[0008] A first boom oil pump, one end of which is connected to a first boom oil circuit, and the other end of which is connected to a second boom oil circuit, wherein the first boom oil circuit is connected to the boom rodless cavity, and the second boom oil circuit is connected to the boom rod cavity;

[0009] a boom balancing valve configured to connect the one with lower oil pressure between the first boom oil circuit and the second boom oil circuit to the oil replenishment oil circuit;

[0010] A first boom oil pump, one end of which is connected to a first boom oil circuit, and the other end of which is connected to a second boom oil circuit, wherein the first boom oil circuit is connected to the boom-less chamber, and the second boom oil circuit is connected to the boom-with-rod chamber;

[0011] A boom balancing valve is configured to connect the one with lower oil pressure between the first boom oil circuit and the second boom oil circuit to the oil replenishment oil circuit;

[0012] A first bucket oil pump, one end of which is connected to a first bucket oil circuit, and the other end of which is connected to a second bucket oil circuit, wherein the first bucket oil circuit is connected to the bucket rodless cavity, and the second bucket oil circuit is connected to the bucket rod cavity;

[0013] The bucket balancing valve is configured to connect one of the first bucket oil passage and the second bucket oil passage having a lower oil pressure to the oil replenishment passage.

[0014] As a preferred technical solution of the hydraulic system with all actuators decoupled, the hydraulic system with all actuators decoupled further includes:

[0015] A second boom oil pump has one end connected to the oil replenishment circuit and the other end connected to the third boom oil circuit, and the third boom oil circuit is connected to the first boom oil circuit.

[0016] As a preferred technical solution for a hydraulic system in which the actuators are completely decoupled, the hydraulic system in which the actuators are completely decoupled further comprises a boom holding valve and a boom pilot valve, the boom holding valve having a first pump side interface and a first cylinder side interface, the boom holding valve being connected in series to the first boom oil circuit via the first pump side interface and the first cylinder side interface, and the first cylinder side interface being close to the boom rodless chamber relative to the first pump side interface, the boom holding valve having a first open state and a first closed state, when the boom holding valve is in the first open state, the first pump side interface and the first cylinder side interface are connected, and when the boom holding valve is in the first closed state, the first pump side interface and the first cylinder side interface are disconnected;

[0017] When the boom holding valve is in the first closed state, the oil pressure at the first pump side interface exceeds the first set value of the oil pressure at the first cylinder side interface, which can cause the boom holding valve to switch to the first open state, or the boom pilot valve controls the boom holding valve to switch to the first open state.

[0018] As an optimal technical solution for the hydraulic system with all decoupled actuators, the hydraulic system with all decoupled actuators also includes a boom control valve arranged in the first boom oil circuit, the boom control valve is arranged in the first boom oil circuit, and the boom control valve is located between the connection between the third boom oil circuit and the first boom oil circuit and the first boom oil pump, and the boom control valve is used to open or close the first boom oil circuit.

[0019] As a preferred technical solution of the hydraulic system with all actuators decoupled, the hydraulic system with all actuators decoupled further includes:

[0020] A second boom oil pump has one end connected to the oil replenishment circuit and the other end connected to a third boom oil circuit, and the third boom oil circuit is connected to the first boom oil circuit.

[0021] As a preferred technical solution for a hydraulic system in which the actuators are completely decoupled, the hydraulic system in which the actuators are completely decoupled further comprises a first boom holding valve and a first boom pilot valve, the first boom holding valve having a second pump side interface and a second cylinder side interface, the first boom holding valve being connected in series to the first boom oil circuit via the second pump side interface and the second cylinder side interface, and the second cylinder side interface being closer to the boom rodless chamber relative to the second pump side interface, the first boom holding valve having a second open state and a second closed state, when the first boom holding valve is in the second open state, the second pump side interface and the second cylinder side interface are connected, and when the first boom holding valve is in the second closed state, the second pump side interface and the second cylinder side interface are disconnected;

[0022] When the first boom holding valve is in the second closed state, the oil pressure at the second pump side interface exceeds the second set value of the oil pressure at the second cylinder side interface, which can cause the first boom holding valve to switch to the second open state, or the first boom pilot valve controls the first boom holding valve to switch to the second open state.

[0023] As a preferred technical solution of the hydraulic system with all actuators decoupled, the hydraulic system with all actuators decoupled further includes:

[0024] a second boom holding valve and a second boom pilot valve, the second boom holding valve having a third pump side interface and a third cylinder side interface, the second boom holding valve being connected in series to the second boom oil circuit via the third pump side interface and the third cylinder side interface, and the third cylinder side interface having a rod cavity close to the boom relative to the third pump side interface, the second boom holding valve having a third open state and a third closed state, when the second boom holding valve is in the third open state, the third pump side interface and the third cylinder side interface are connected, and when the second boom holding valve is in the third closed state, the third pump side interface and the third cylinder side interface are disconnected;

[0025] When the second boom holding valve is in the third closed state, the oil pressure at the third pump side interface exceeds the third set value of the oil pressure at the third cylinder side interface, so that the second boom holding valve switches to the third open state, or the second boom pilot valve controls the second boom holding valve to switch to the third open state.

[0026] As a preferred technical solution of the hydraulic system with fully decoupled actuators, the hydraulic system with fully decoupled actuators further includes a boom control valve, the boom control valve is arranged in the first boom oil circuit, and the boom control valve is located between the connection between the third boom oil circuit and the first boom oil circuit and the first boom oil pump, and the boom control valve is used to open or close the first boom oil circuit;

[0027] The arm control valve is configured to open the first arm oil circuit when the first arm pilot valve controls the first arm holding valve to switch to the second open state, or when the second arm pilot valve controls the second arm holding valve to switch to the third open state.

[0028] As a preferred technical solution for the hydraulic system with all decoupled actuators, the hydraulic system with all decoupled actuators also includes a boom regeneration valve, which is configured to connect the first boom oil circuit and the second boom oil circuit, or to disconnect the first boom oil circuit and the second boom oil circuit.

[0029] As a preferred technical solution of the hydraulic system with all actuators decoupled, the hydraulic system with all actuators decoupled further includes:

[0030] A second bucket oil pump has one end connected to the oil replenishment circuit and the other end connected to a third bucket oil circuit, and the third bucket oil circuit is connected to the first bucket oil circuit.

[0031] As a preferred technical solution for a hydraulic system in which the actuators are completely decoupled, the hydraulic system in which the actuators are completely decoupled further comprises a first bucket holding valve and a first bucket pilot valve, the first bucket holding valve having a fourth pump side interface and a fourth cylinder side interface, the first bucket holding valve being connected in series to the first bucket oil circuit via the fourth pump side interface and the fourth cylinder side interface, and the fourth cylinder side interface being close to the bucket rodless chamber relative to the fourth pump side interface, the first bucket holding valve having a fourth open state and a fourth closed state, when the first bucket holding valve is in the fourth open state, the fourth pump side interface and the fourth cylinder side interface are connected, and when the first bucket holding valve is in the fourth closed state, the fourth pump side interface and the fourth cylinder side interface are disconnected;

[0032] When the first bucket holding valve is in the fourth closed state, the oil pressure at the fourth pump side interface exceeds the fourth set value of the oil pressure at the fourth cylinder side interface, which can cause the first bucket holding valve to switch to the fourth open state, or the first bucket pilot valve controls the first bucket holding valve to switch to the fourth open state.

[0033] As a preferred technical solution of the hydraulic system with fully decoupled actuators, the hydraulic system with fully decoupled actuators further comprises a second bucket holding valve and a second bucket pilot valve, the second bucket holding valve having a fifth pump side interface and a fifth cylinder side interface, the second bucket holding valve being connected in series to the second bucket oil circuit via the fifth pump side interface and the fifth cylinder side interface, and the fifth cylinder side interface having a rod cavity close to the bucket relative to the fifth pump side interface, the second bucket holding valve having a fifth open state and a fifth closed state, when the second bucket holding valve is in the fifth open state, the fifth pump side interface and the fifth cylinder side interface are connected, and when the second bucket holding valve is in the fifth closed state, the fifth pump side interface and the fifth cylinder side interface are disconnected;

[0034] When the second bucket holding valve is in the fifth closed state, the oil pressure at the fifth pump side interface exceeds the fifth set value of the oil pressure at the fifth cylinder side interface, so that the second bucket holding valve switches to the fifth open state, or the second bucket pilot valve controls the second bucket holding valve to switch to the fifth open state.

[0035] As a preferred technical solution of the hydraulic system with fully decoupled actuators, the hydraulic system with fully decoupled actuators further includes a bucket control valve, which is arranged in the first bucket oil circuit, and the bucket control valve is located between the connection between the third bucket oil circuit and the first bucket oil circuit and the first bucket oil pump, and the bucket control valve is used to open or close the first bucket oil circuit;

[0036] The bucket control valve is configured to open the first bucket oil passage when the first bucket pilot valve controls the first bucket holding valve to switch to the fourth open state or when the second bucket pilot valve controls the second bucket holding valve to switch to the fifth open state.

[0037] As a preferred technical solution for the hydraulic system with all decoupled actuators, the hydraulic system with all decoupled actuators also includes a bucket regeneration valve, and the bucket regeneration valve is configured to connect the first bucket oil circuit and the second bucket oil circuit, or to disconnect the first bucket oil circuit and the second bucket oil circuit.

[0038] The hydraulic system with all actuators decoupled provided by the present invention has at least the following beneficial effects:

[0039] The hydraulic system in which the actuator is completely decoupled includes an oil replenishment pump, a first boom oil pump, a boom balancing valve, a first dipper arm oil pump, a dipper arm balancing valve, a first bucket oil pump and a bucket balancing valve. One end of the oil replenishment pump is connected to the oil tank, and the other end is connected to the oil replenishment circuit; the first boom oil pump forms a boom hydraulic circuit with the two chambers of the boom cylinder through the first boom oil circuit and the second boom oil circuit, and the boom balancing valve is configured to connect the one with the smaller oil pressure in the first boom oil circuit and the second boom oil circuit to the oil replenishment circuit, so that the hot oil in the boom hydraulic circuit is replaced with the low-temperature oil in the oil replenishment circuit, ensuring that the boom cylinder can work normally; the first dipper arm oil pump forms a dipper arm hydraulic circuit with the two chambers of the dipper arm cylinder through the first dipper arm oil circuit and the second dipper arm oil circuit, and the dipper arm balancing valve is configured to connect The one with smaller oil pressure in the first boom oil circuit and the second boom oil circuit is connected to the oil replenishing circuit, so that the hot oil in the boom hydraulic circuit is replaced by the low-temperature oil in the oil replenishing circuit, ensuring that the boom cylinder can work normally; the first bucket oil pump forms a bucket hydraulic circuit with the two chambers of the bucket cylinder through the first bucket oil circuit and the second bucket oil circuit, and the bucket balancing valve is configured to connect the one with smaller oil pressure in the first bucket oil circuit and the second bucket oil circuit to the oil replenishing circuit, so that the hot oil in the bucket hydraulic circuit is replaced by the low-temperature oil in the oil replenishing circuit, ensuring that the bucket cylinder can work normally.

[0040] On the other hand, the present invention provides an excavator, which includes a hydraulic system in which the actuators in any of the above-mentioned schemes are completely decoupled, and the excavator also includes an excavator body, a boom articulated to the excavator body, a dipper arm articulated to the boom, and a bucket articulated to the dipper arm, the boom cylinder body of the boom cylinder is articulated to the excavator body, the boom piston rod of the boom cylinder is articulated to the boom, the dipper arm cylinder body of the dipper arm cylinder is articulated to the boom, the dipper arm piston rod of the dipper arm cylinder is articulated to the dipper arm, the bucket cylinder body of the bucket cylinder is articulated to the dipper arm, and the bucket piston rod of the bucket cylinder is articulated to the bucket.

[0041] As a preferred technical solution for the excavator, the excavator further includes a drive system, which is an extended-range drive system, a pure electric drive system or a hybrid drive system.

[0042] The excavator provided by the present invention has at least the following beneficial effects:

[0043] The excavator includes a hydraulic system with all the above-mentioned actuators decoupled, which can achieve full decoupling of the boom cylinder, bucket cylinder and stick cylinder, enhance operability, and effectively improve the thermal balance of the boom hydraulic circuit, stick hydraulic circuit and bucket hydraulic circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic diagram of a first partial structure of a hydraulic system in which all actuators are decoupled in an embodiment of the present invention;

[0045] Figure 2 It is a second partial structural schematic diagram of a hydraulic system in which all actuators are decoupled in an embodiment of the present invention;

[0046] Figure 3 It is a third partial structural schematic diagram of the hydraulic system in which all actuators are decoupled in an embodiment of the present invention;

[0047] Figure 4 It is a fourth partial structural diagram of a hydraulic system in which all actuators are decoupled according to an embodiment of the present invention;

[0048] Figure 5 A fifth partial structural diagram of a hydraulic system in which all actuators are decoupled according to an embodiment of the present invention;

[0049] Figure 6 It is a sixth partial structural diagram of a hydraulic system in which all actuators are decoupled according to an embodiment of the present invention;

[0050] Figure 7 It is a seventh partial structural schematic diagram of a hydraulic system in which all actuators are decoupled according to an embodiment of the present invention;

[0051] Figure 8 It is an eighth partial structural schematic diagram of a hydraulic system in which all actuators are decoupled according to an embodiment of the present invention;

[0052] Fig. 9 This is a ninth partial structural diagram of a hydraulic system in which all actuators are decoupled in an embodiment of the present invention.

[0053] In the figure:

[0054] 1. Boom cylinder; 101. Boom rod chamber; 102. Boom rodless chamber;

[0055] 2. Arm cylinder; 201, arm with rod cavity; 202, arm without rod cavity;

[0056] 3. Bucket cylinder; 301. Bucket with rod chamber; 302. Bucket without rod chamber;

[0057] 4. Oil supply pump; 5. Oil tank; 6. Oil supply circuit; 7. Oil supply overflow valve;

[0058] 8. First boom oil pump; 9. Boom balance valve; 10. First boom oil circuit; 11. Second boom oil circuit; 12. Second boom oil pump; 13. Third boom oil circuit; 14. Boom holding valve; 15. Boom pilot valve; 16. First solenoid switch valve; 17. Boom control valve; 18. Second solenoid switch valve; 19. First oil replenishment check valve; 20. Second oil replenishment check valve; 21. First overflow valve; 22. Second overflow valve;

[0059] 23. First arm oil pump; 24. Arm balancing valve; 25. First arm oil circuit; 26. Second arm oil circuit; 27. Second arm oil pump; 28. Third arm oil circuit; 29. ​​First arm holding valve; 30. First arm pilot valve; 31. Third solenoid switch valve; 32. Second arm holding valve; 33. Second arm pilot valve; 34. Fourth solenoid switch valve; 35. Arm control valve; 36. Third oil replenishment check valve; 37. Fourth oil replenishment check valve; 38. Third overflow valve; 39. Fourth overflow valve; 40. Arm regeneration valve; 41. Regeneration control valve;

[0060] 42. First bucket oil pump; 43. Bucket balancing valve; 44. First bucket oil circuit; 45. Second bucket oil circuit; 46. Second bucket oil pump; 47. Third bucket oil circuit; 48. First bucket holding valve; 49. First bucket pilot valve; 50. Fifth solenoid switch valve; 51. Second bucket holding valve; 52. Second bucket pilot valve; 53. Sixth solenoid switch valve; 54. Bucket control valve; 55. Fifth oil replenishment check valve; 56. Sixth oil replenishment check valve; 57. Fifth overflow valve; 58. Sixth overflow valve; 59. Bucket regeneration valve;

[0061] 60. First motor; 61. Second motor; 62. Third motor; 63. Battery; 64. First internal combustion engine; 65. First generator; 66. Second internal combustion engine; 67. Second generator; 68. Rotary motor; 69. Left travel motor; 70. Right travel motor; 71. Oil replenishment motor. DETAILED DESCRIPTION

[0062] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. 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.

[0063] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions, and the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0064] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0065] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0066] In the prior art, the hydraulic system with completely decoupled actuators supplies oil to all actuators through independent oil sources, thereby achieving complete decoupling of each circuit and eliminating energy waste caused by load coupling when multiple actuators of the excavator perform compound actions. In addition, the rod chamber and rodless chamber of the oil cylinder can be connected by an oil pump to achieve the flow of oil in the two chambers, and an accumulator is configured to compensate for the flow difference between the rod chamber and the rodless chamber and recover part of the energy, thereby achieving complete decoupling of the oil cylinder. However, in this system, the accumulator will overflow at high pressure when the maximum pressure is reached, which will cause power loss. In addition, the high-pressure overflow will generate a lot of heat and affect the thermal balance of the system. In order to avoid excessive oil temperature in the system, additional temperature monitoring is required. When the temperature is abnormal, the hot oil in the system needs to overflow to the oil tank through a low-pressure overflow valve, and the oil in the oil tank is replenished into the system, affecting the normal operation of the oil cylinder.

[0067] In this regard, the present embodiment provides a hydraulic system with fully decoupled actuators to solve the above-mentioned problem. The hydraulic system with fully decoupled actuators can be integrated into an excavator.

[0068] like Figures 1 to 6 As shown, the hydraulic system with all the actuators decoupled includes a boom cylinder 1 , a bucket cylinder 3 and an arm cylinder 2 .

[0069] Please refer to Figure 1 and Figure 2 The boom cylinder 1 includes a boom rod chamber 101 and a boom rodless chamber 102 with variable volumes. The boom cylinder 1 also includes a boom piston rod and a boom cylinder body. The boom piston rod divides the inner cavity of the boom cylinder body into the boom rod chamber 101 and the boom rodless chamber 102. The boom piston rod passes through the boom rod chamber 101 so that the cross-sectional area of ​​the boom rod chamber 101 is smaller than the cross-sectional area of ​​the boom rodless chamber 102. The boom piston rod can move in the boom cylinder body, and when the boom piston rod moves, the volumes of the boom rod chamber 101 and the boom rodless chamber 102 increase and decrease. In this embodiment, the boom cylinder body is hinged to the body of the excavator, the boom piston rod is hinged to the boom, and the number of the boom cylinders 1 is specifically two.

[0070] Please refer to Figure 3 and Figure 4The arm oil cylinder 2 includes an arm rod chamber 201 and an arm rodless chamber 202 with variable volumes. The arm oil cylinder 2 also includes an arm piston rod and an arm cylinder body. The arm piston rod divides the inner cavity of the arm cylinder body into the arm rod chamber 201 and the arm rodless chamber 202. The arm piston rod passes through the arm rod chamber 201 so that the cross-sectional area of ​​the arm rod chamber 201 is smaller than the cross-sectional area of ​​the arm rodless chamber 202. The arm piston rod can move in the arm cylinder body, and when the arm piston rod moves, the volumes of the arm rod chamber 201 and the arm rodless chamber 202 increase and decrease. In this embodiment, the arm cylinder body is hinged to the boom, the arm piston rod is hinged to the arm, and the number of the arm oil cylinder 2 is specifically one.

[0071] Please refer to Figure 5 and Figure 6 The bucket oil cylinder 3 includes a bucket rod chamber 301 and a bucket rodless chamber 302 with variable volumes. The bucket oil cylinder 3 also includes a bucket piston rod and a bucket cylinder body. The bucket piston rod divides the inner cavity of the bucket cylinder body into the bucket rod chamber 301 and the bucket rodless chamber 302. The bucket piston rod passes through the bucket rod chamber 301 so that the cross-sectional area of ​​the bucket rod chamber 301 is smaller than the cross-sectional area of ​​the bucket rodless chamber 302. The bucket piston rod can move in the bucket cylinder body, and when the bucket piston rod moves, the volumes of the bucket rod chamber 301 and the bucket rodless chamber 302 increase and decrease. In this embodiment, the bucket cylinder body is hinged to the boom, the bucket piston rod is hinged to the bucket, and the number of bucket oil cylinders 3 is specifically one.

[0072] Please refer to Figures 1 to 6 The hydraulic system with all decoupled actuators further includes an oil replenishment pump 4. One end of the oil replenishment pump 4 is connected to the oil tank 5, and the other end is connected to the oil replenishment oil circuit 6. The oil replenishment pump 4 can pump the oil in the oil tank 5 to the oil replenishment oil circuit 6, and the oil replenishment oil circuit 6 can supply oil to other oil circuits.

[0073] Optionally, the hydraulic system with all actuators decoupled further includes an oil replenishment overflow valve 7 connected to the oil replenishment oil circuit 6 , and the oil replenishment overflow valve 7 is used to overflow the oil in the oil replenishment oil circuit 6 that exceeds a set pressure to the oil tank 5 .

[0074] Optionally, the hydraulic system with all actuators decoupled further includes an oil replenishment motor 71, which is in transmission connection with the oil replenishment pump 4, and is used to drive the oil replenishment pump 4 to rotate. In this embodiment, the oil replenishment pump 4 is specifically an open pump.

[0075] Optionally, see Figure 1 and Figure 2The hydraulic system with all actuators decoupled also includes a first boom oil pump 8 and a boom balance valve 9. Among them, one end of the first boom oil pump 8 is connected to the first boom oil circuit 10, and the other end of the first boom oil pump 8 is connected to the second boom oil circuit 11. The first boom oil circuit 10 is connected to the boom rodless chamber 102, and the second boom oil circuit 11 is connected to the boom rod chamber 101; the first boom oil pump 8 forms a boom hydraulic circuit with two chambers of the boom cylinder 1 through the first boom oil circuit 10 and the second boom oil circuit 11. The boom balance valve 9 is configured to connect the one with smaller oil pressure in the first boom oil circuit 10 and the second boom oil circuit 11 to the oil replenishment circuit 6. Since the cross-sectional areas of the boom rod chamber 101 and the boom rodless chamber 102 are different, there is a flow difference. When the first boom oil pump 8 drives the oil to flow between the boom rod chamber 101 and the boom rodless chamber 102, the flow difference can be balanced by the boom balance valve 9, and the oil temperature in the oil replenishing circuit 6 is relatively low, and the hot oil in the boom hydraulic circuit can be replaced with the low-temperature oil in the oil replenishing circuit, which can ensure the normal oil temperature in the boom hydraulic circuit, and then ensure the normal operation of the boom cylinder 1. Compared with the existing technology, there is no need to configure temperature monitoring, and the cost can be effectively reduced.

[0076] In this embodiment, the first boom oil pump 8 adopts a closed pump. The first boom oil pump 8 can rotate forward and reverse. Compared with an open pump, it can significantly reduce the energy loss of the system. The first boom oil pump 8 supplies oil to the boom cylinder 1 so that the boom oil pump can be decoupled, thereby improving the controllability of the boom oil circuit.

[0077] Optionally, the hydraulic system with all actuators decoupled further includes a second boom oil pump 12, one end of the second boom oil pump 12 is connected to the oil replenishment circuit 6, the other end of the second boom oil pump 12 is connected to the third boom oil circuit 13, and the third boom oil circuit 13 is connected to the first boom oil circuit 10. The second boom oil pump 12 is only used to supply oil to the boom rodless chamber 102 or drain oil at the same time as the first boom oil pump 8, so as to further balance the flow difference between the boom rod chamber 101 and the boom rodless chamber 102.

[0078] In this embodiment, the second boom oil pump 12 can also rotate forward and reverse, and the second boom oil pump 12 adopts a closed pump. Specifically, both the first boom oil pump 8 and the second boom oil pump 12 can adopt a quantitative pump.

[0079] It should be noted that the movement direction of the boom piston rod and the direction of the load force applied to the boom piston rod jointly determine the oil pressure in the boom rodless chamber 102 and the boom rod chamber 101. When the direction of the load force is consistent with the movement direction of the boom piston rod, the load force is a negative load. When the direction of the load force is opposite to the movement direction of the boom piston rod, the load force is a positive load.

[0080] In this embodiment, the boom piston rod can move relative to the boom cylinder body and have a first extended position and a first retracted position. When the boom piston rod moves to the first extended position, the boom piston rod gradually extends to the outside, and the first boom oil pump 8 rotates forward and pumps the oil in the boom rod chamber 101 into the boom rodless chamber 102. However, due to the flow difference between the boom rod chamber 101 and the boom rodless chamber 102, it is also necessary to use the second boom oil pump 12 to simultaneously pump the oil in the oil replenishment circuit 6 into the boom rodless chamber 102 to compensate for the flow difference. At this time, the second boom oil pump 12 also rotates forward. If the boom piston rod is under positive load at this time, the oil pressure in the boom rod chamber 101 is lower than the oil pressure in the boom rodless chamber 102, then the boom balancing valve 9 connects the second boom oil circuit 11 and the oil replenishing circuit 6. If the boom piston rod is under negative load at this time, the oil pressure in the boom rod chamber 101 is higher than the oil pressure in the boom rodless chamber 102, then the boom balancing valve 9 connects the first boom oil circuit 10 and the oil replenishing circuit 6.

[0081] When the boom piston rod moves to the first retracted position, the boom piston rod gradually retracts inward, the first boom oil pump 8 rotates in the opposite direction, and pumps a part of the oil in the boom rodless chamber 102 into the boom rod chamber 101. At the same time, the second boom oil pump 12 rotates in the opposite direction, and the second boom oil pump 12 pumps another part of the oil in the boom rodless chamber 102 to the oil replenishing circuit 6. If the boom piston rod is subjected to a positive load at this time, the oil pressure in the boom rod chamber 101 is greater than the oil pressure in the boom rodless chamber 102, then the boom balance valve 9 connects the first boom oil circuit 10 and the oil replenishing circuit 6. If the boom piston rod is subjected to a negative load at this time, the oil pressure in the boom rod chamber 101 is less than the oil pressure in the boom rodless chamber 102, then the boom balance valve 9 connects the second boom oil circuit 11 and the oil replenishing circuit 6.

[0082] Specifically, in this embodiment, the boom balance valve 9 includes a P1 interface, an A 11 Interface and A 12 Interface, where P1 interface is connected to oil replenishment line 6, A 11 The interface is connected to the first boom oil circuit 10, A 12 The boom balance valve 9 has a first left position and a first right position. When the boom balance valve 9 is in the first left position, the boom balance valve 9 makes the P1 interface and A interface communicate with each other. 12 The interface is connected and A 11 The interface is disconnected, so that the oil supply oil circuit 6 is connected to the second boom oil circuit 11, and the first boom oil circuit 10 is disconnected; when the boom balance valve 9 is in the first right position, the boom balance valve 9 makes the P1 interface and A 11 The interface is connected and A 12The interface is disconnected, so that the oil supply oil circuit 6 is connected to the first boom oil circuit 10, and the second boom oil circuit 11 is disconnected. Preferably, the boom balance valve 9 also has a first middle position. When the boom balance valve 9 is in the first middle position, the P1 interface is disconnected, A 11 The interface is disconnected and A 12 The interface is disconnected, thereby disconnecting the oil replenishment circuit 6 from the first boom oil circuit 10 and the second boom oil circuit 11 at the same time.

[0083] In the present embodiment, the boom balancing valve 9 is specifically a hydraulically controlled valve, and the boom balancing valve 9 has a hydraulic control end A1 and a hydraulic control end A2. The hydraulic control end A1 is connected to the first boom oil circuit 10, and the hydraulic control end A2 is connected to the second boom oil circuit 11. The hydraulic control end A1 and the hydraulic control end A2 are respectively located on both sides of the valve core of the boom balancing valve 9, and the oil of the hydraulic control end A1 and the hydraulic control end A2 directly acts on the valve core of the boom balancing valve 9. The force of the oil of the hydraulic control end A1 acting on the valve core of the boom balancing valve 9 and the force of the oil of the hydraulic control end A2 acting on the valve core of the boom balancing valve 9 are compared to determine the stop position of the valve core of the boom balancing valve 9. Specifically, when the oil pressure of the hydraulic control end A1 is greater than the oil pressure of the hydraulic control end A2, the boom balance valve 9 is located in the first left position; when the oil pressure of the hydraulic control end A1 is less than the oil pressure of the hydraulic control end A2, the boom balance valve 9 is located in the first right position; when the oil pressure of the hydraulic control end A1 is equal to the oil pressure of the hydraulic control end A2, the boom balance valve 9 is located in the first middle position. In other embodiments, the boom balance valve 9 can also be an electrically controlled valve.

[0084] Optionally, the hydraulic system in which all actuators are decoupled also includes a boom holding valve 14 and a boom pilot valve 15, the boom holding valve 14 having a first pump side interface and a first cylinder side interface, the boom holding valve 14 being connected in series to the first boom oil circuit 10 via the first pump side interface and the first cylinder side interface, and the first cylinder side interface being close to the boom rodless chamber 102 relative to the first pump side interface, the boom holding valve 14 having a first open state and a first closed state, when the boom holding valve 14 is in the first open state, the first pump side interface and the first cylinder side interface are connected, and when the boom holding valve 14 is in the first closed state, the first pump side interface and the first cylinder side interface are disconnected; when the boom holding valve 14 is in the first closed state, when the oil pressure at the first pump side interface exceeds the first set value of the oil pressure at the first cylinder side interface, the boom holding valve 14 can be switched to the first open state, or the boom holding valve 14 can be switched to the first open state by controlling the boom pilot valve 15. Among them, by setting the boom holding valve 14, when it disconnects the first boom oil circuit 10, the oil pressure in the boom rodless chamber 102 can be kept stable, thereby ensuring that the position of the boom piston rod can remain stable.

[0085] Among them, the boom holding valve 14 includes a one-way valve housing and a one-way valve core, and the first pump side interface and the first cylinder side interface are arranged in the one-way valve housing; the one-way valve core slides in the one-way valve housing, and the one-way valve core divides the inner cavity of the one-way valve housing into a spring cavity and a working cavity. The one-way valve core can slide relative to the one-way valve housing so that the boom holding valve 14 has a first open state and a first closed state. When the boom holding valve 14 is in the first closed state, the one-way valve core can further divide the working cavity into a first cavity and a second cavity that are not connected to each other, wherein the first pump side interface is always connected to the first cavity, and the first cylinder side interface is always connected to the second cavity. Since the first cavity and the second cavity are separated at this time, the first boom oil circuit 10 is disconnected; when the boom holding valve 14 is in the first open state, the first cavity and the second cavity are connected, and the first boom oil circuit 10 is connected at this time. A one-way valve spring is provided in the spring chamber. The one-way valve spring is located in the spring chamber and two ends of the one-way valve spring are respectively abutted against the one-way valve core and the one-way valve housing. The one-way valve housing has a first control interface and a second control interface. The first control interface is always connected to the first chamber, and the second control interface is always connected to the spring chamber. The one-way valve spring and the hydraulic oil in the spring chamber give the one-way valve core a force F1 to move to a closed position, and the hydraulic oil in the working chamber gives the one-way valve core a force F2 to move to an open position. The position of the one-way valve core is determined by comparing the sizes of F1 and F2, thereby determining the state of the boom holding valve 14.

[0086] In this embodiment, the boom pilot valve 15 is a two-position three-way valve, and the boom pilot valve 15 can make the first control interface and the second control interface communicate, so that the boom holding valve 14 is in the first open state. Specifically, when the boom pilot valve 15 makes the first control interface and the second control interface communicate, the oil pressure in the first chamber and the spring chamber is equal, but the oil in the first chamber and the one-way valve core have an action area smaller than the oil in the spring chamber and the one-way valve core, and the one-way valve spring in the spring chamber also gives the one-way valve core an action force, which can make the one-way valve core move to a position that separates the first chamber and the second chamber, so that the boom holding valve 14 is in the first open state. The boom pilot valve 15 can also make the second control interface and the oil tank 5 communicate, and at this time, the position of the one-way valve core is determined by comparing the sizes of F1 and F2, and then the state of the boom holding valve 14 is determined. Among them, when F1 is less than F2, the one-way valve spring is compressed, which can make the one-way valve core move to the open position, so that the first boom oil circuit 10 is opened.

[0087] Among them, the boom pilot valve 15 is specifically a hydraulically controlled reversing valve, and the working position of the boom pilot valve 15 can be controlled by the on-off of the signal oil source of the hydraulically controlled reversing valve, so that the first control interface and the second control interface can be connected, or the second control interface and the oil tank 5 are connected and the first control interface is disconnected. In other embodiments, the boom pilot valve 15 can also be replaced by an electrically controlled reversing valve. Specifically, in this embodiment, the first control valve also includes a first electromagnetic switch valve 16 for controlling the on-off of the oil circuit of the hydraulic control end of the boom pilot valve 15, so the on-off of the signal oil source of the boom pilot valve 15 can be controlled by the first electromagnetic switch valve 16 to realize the switching control of the working position of the boom pilot valve 15.

[0088] Optionally, the hydraulic system in which the actuators are completely decoupled also includes a boom control valve 17 disposed in the first boom oil circuit 10. The boom control valve 17 is located between the connection between the third boom oil circuit 13 and the first boom oil circuit 10 and the first boom oil pump 8. The boom control valve 17 is used to open or close the first boom oil circuit 10. When the boom control valve 17 disconnects the first boom oil circuit 10, it can block the first boom oil pump 8 from supplying oil to the boom rodless chamber 102, and can prevent the oil in the boom rodless chamber 102 from flowing to the first boom oil pump 8, further ensuring the stability of the position of the boom piston rod. Specifically, the boom control valve 17 has a second left position, a second middle position, and a second right position. When the boom control valve 17 is in the second left position and the second right position, the first boom oil circuit 10 is conducted. When the boom control valve 17 is in the second middle position, the first boom oil circuit 10 is disconnected.

[0089] The boom control valve 17 includes a hydraulic control end B1 and a hydraulic control end B2. The first solenoid switch valve 16 is also used to control the on-off of the oil circuit of the hydraulic control end B1. The hydraulic system with all decoupled actuators also includes a second solenoid switch valve 18. The second solenoid switch valve 18 is also used to control the on-off of the oil circuit of the hydraulic control end B2. The hydraulic control end B1 and the hydraulic control end B2 are respectively located on both sides of the valve core of the boom control valve 17, and the oil of the hydraulic control end B1 and the hydraulic control end B2 directly acts on the valve core of the boom control valve 17. The force of the oil of the hydraulic control end B1 acting on the valve core of the boom control valve 17 is compared with the force of the oil of the hydraulic control end B2 acting on the valve core of the boom control valve 17 to determine the stop position of the valve core of the boom control valve 17. With such arrangement, the first electromagnetic switch valve 16 controls the boom control valve 17 and the boom holding valve 14 simultaneously. When the boom holding valve 14 is in the first open state, the boom control valve 17 simultaneously opens the first boom oil circuit 10, so that the boom hydraulic circuit is conductive.

[0090] Optionally, the hydraulic system in which the actuators are completely decoupled also includes a first oil replenishment check valve 19 and a second oil replenishment check valve 20, the first oil replenishment check valve 19 being connected between the oil replenishment circuit 6 and the boom rodless chamber 102, and the first oil replenishment check valve 19 only allows oil to flow from the oil replenishment circuit 6 to the boom rodless chamber 102, specifically, the first oil replenishment check valve 19 is connected between the oil replenishment circuit 6 and the first boom oil circuit 10; the second oil replenishment check valve 20 is connected between the oil replenishment circuit 6 and the boom rod chamber 101, and the second oil replenishment check valve 20 only allows oil to flow from the oil replenishment circuit 6 to the boom rod chamber 101, specifically, the second oil replenishment check valve 20 is connected between the oil replenishment circuit 6 and the second boom oil circuit 11. By providing the first oil replenishment check valve 19, when the oil pressure in the boom rodless chamber 102 is low, the boom rodless chamber 102 can be replenished with oil through the oil replenishment oil circuit 6; by providing the second oil replenishment check valve 20, when the oil pressure in the boom rod chamber 101 is low, the boom rod chamber 101 can be replenished with oil through the oil replenishment oil circuit 6 to further balance the flow difference between the boom rod chamber 101 and the boom rodless chamber 102. Specifically, the connection between the first oil replenishment check valve 19 and the first boom oil circuit 10 is located between the boom holding valve 14 and the boom cylinder 1.

[0091] Optionally, the hydraulic system with all actuators decoupled further includes a first relief valve 21 and a second relief valve 22, wherein the first relief valve 21 is connected between the oil replenishment circuit 6 and the first boom oil circuit 10, and the first relief valve 21 only allows oil to overflow from the boom rodless chamber 102 through the first boom oil circuit 10 to the oil replenishment circuit 6, specifically, the connection between the first relief valve 21 and the first boom oil circuit 10 is located between the boom holding valve 14 and the boom cylinder 1; the second relief valve 22 is connected between the oil replenishment circuit 6 and the second boom oil circuit 11, and the second relief valve 22 only allows oil to overflow from the boom rod chamber 101 through the second boom oil circuit 11 to the oil replenishment circuit 6. By providing the first relief valve 21 and the second relief valve 22, it is possible to effectively avoid excessive oil pressure in the boom rod chamber 101 and the boom rodless chamber 102.

[0092] Please refer to Figure 3 and Figure 4The hydraulic system with all actuators decoupled also includes a first boom oil pump 23 and a boom balancing valve 24. One end of the first boom oil pump 23 is connected to the first boom oil circuit 25, and the other end of the first boom oil pump 23 is connected to the second boom oil circuit 26. The first boom oil circuit 25 is connected to the boom rodless chamber 202, and the second boom oil circuit 26 is connected to the boom rod chamber 201. The first boom oil pump 23 forms a boom hydraulic circuit with the two chambers of the boom cylinder 2 through the first boom oil circuit 25 and the second boom oil circuit 26. The boom balancing valve 24 is configured to connect the one with smaller oil pressure in the first boom oil circuit 25 and the second boom oil circuit 26 to the oil replenishment circuit 6. Since the cross-sectional areas of the boom rod chamber 201 and the boom rodless chamber 202 are different, there is a flow difference. When the first boom oil pump 23 drives the oil to flow between the boom rod chamber 201 and the boom rodless chamber 202, the flow difference can be balanced by the boom balance valve 24, and the oil temperature in the oil replenishing circuit 6 is relatively low, and the hot oil in the boom hydraulic circuit can be replaced with the low-temperature oil in the oil replenishing circuit, which can ensure the normal oil temperature in the boom hydraulic circuit and further ensure the normal operation of the boom cylinder 2. Compared with the existing technology, there is no need to configure temperature monitoring, and the cost can be effectively reduced.

[0093] In this embodiment, the first boom oil pump 23 adopts a closed pump. The first boom oil pump 23 can rotate forward and reverse. Compared with an open pump, it can significantly reduce the energy loss of the system. The first boom oil pump 23 supplies oil to the boom cylinder 2 so that the boom oil pump can be decoupled, thereby improving the controllability of the boom oil circuit.

[0094] Optionally, the hydraulic system with all actuators decoupled further includes a second arm oil pump 27, one end of which is connected to the oil replenishment circuit 6, and the other end of which is connected to the third arm oil circuit 28, which is connected to the first arm oil circuit 25. The second arm oil pump 27 is only used to supply oil to the arm rodless chamber 202 or drain oil at the same time as the first arm oil pump 23, so as to further balance the flow difference between the arm rod chamber 201 and the arm rodless chamber 202.

[0095] In this embodiment, the second arm oil pump 27 can also rotate forward and reverse, and the second arm oil pump 27 adopts a closed pump. Specifically, the first arm oil pump 23 and the second arm oil pump 27 can both adopt a quantitative pump.

[0096] In this embodiment, the boom piston rod can move relative to the boom cylinder body and have a second extended position and a second retracted position. When the boom piston rod moves to the second extended position, the boom piston rod gradually extends to the outside, and the first boom oil pump 23 rotates forward and pumps the oil in the boom rod chamber 201 into the boom rodless chamber 202. However, due to the flow difference between the boom rod chamber 201 and the boom rodless chamber 202, it is also necessary to use the second boom oil pump 27 to simultaneously pump the oil in the oil replenishment circuit 6 into the boom rodless chamber 202 to compensate for the flow difference. At this time, the second boom oil pump 27 also rotates forward. If the boom piston rod is under positive load at this time, and the oil pressure in the boom rod chamber 201 is lower than the oil pressure in the boom rodless chamber 202, then the boom balance valve 24 connects the second boom oil circuit 26 and the oil replenishing circuit 6. If the boom piston rod is under negative load at this time, and the oil pressure in the boom rod chamber 201 is higher than the oil pressure in the boom rodless chamber 202, then the boom balance valve 24 connects the first boom oil circuit 25 and the oil replenishing circuit 6.

[0097] When the boom piston rod moves to the second retracted position, the boom piston rod gradually retracts inward, the first boom oil pump 23 rotates in the opposite direction, and pumps a portion of the oil in the boom rodless chamber 202 into the boom rod chamber 201. At the same time, the second boom oil pump 27 rotates in the opposite direction, and the second boom oil pump 27 pumps another portion of the oil in the boom rodless chamber 202 into the oil replenishment circuit 6. If the boom piston rod is subjected to a positive load at this time, the oil pressure in the boom rod chamber 201 is greater than the oil pressure in the boom rodless chamber 202, then the boom balance valve 24 connects the first boom oil circuit 25 and the oil replenishment circuit 6. If the boom piston rod is subjected to a negative load at this time, the oil pressure in the boom rod chamber 201 is less than the oil pressure in the boom rodless chamber 202, then the boom balance valve 24 connects the second boom oil circuit 26 and the oil replenishment circuit 6.

[0098] Specifically, in this embodiment, the arm balance valve 24 includes a P2 interface, an A 21 Interface and A 22 Interface, where P2 interface is connected to oil replenishment line 6, A 21 The interface is connected to the first boom oil circuit 25, A 22 The boom balance valve 24 has a third left position and a third right position. When the boom balance valve 24 is in the third left position, the boom balance valve 24 makes the P2 interface and A communicate. 22 The interface is connected and A 21 The interface is disconnected, so that the oil supply oil circuit 6 is connected to the second bucket oil circuit 26, and the first bucket oil circuit 25 is disconnected; when the bucket balance valve 24 is in the third right position, the bucket balance valve 24 makes the P2 interface and A 21 The interface is connected and A 22The interface is disconnected, so that the oil supply oil circuit 6 is connected to the first boom oil circuit 25, and the second boom oil circuit 26 is disconnected. Preferably, the boom balance valve 24 also has a third middle position. When the boom balance valve 24 is in the third middle position, the P2 interface is disconnected, A 21 The interface is disconnected and A 22 The interface is disconnected, so that the oil replenishment circuit 6 is disconnected from the first boom oil circuit 25 and the second boom oil circuit 26 at the same time.

[0099] In the present embodiment, the boom balancing valve 24 is specifically a hydraulically controlled valve, and the boom balancing valve 24 has a hydraulic control end C1 and a hydraulic control end C2. The hydraulic control end C1 is connected to the first boom oil circuit 25, and the hydraulic control end C2 is connected to the second boom oil circuit 26. The hydraulic control end C1 and the hydraulic control end C2 are respectively located on both sides of the valve core of the boom balancing valve 24, and the oil of the hydraulic control end C1 and the hydraulic control end C2 directly acts on the valve core of the boom balancing valve 24. The force of the oil of the hydraulic control end C1 acting on the valve core of the boom balancing valve 24 and the force of the oil of the hydraulic control end C2 acting on the valve core of the boom balancing valve 24 are compared to determine the stop position of the valve core of the boom balancing valve 24. Specifically, when the oil pressure of the hydraulic control end C1 is greater than the oil pressure of the hydraulic control end C2, the arm balance valve 24 is located in the third left position; when the oil pressure of the hydraulic control end C1 is less than the oil pressure of the hydraulic control end C2, the arm balance valve 24 is located in the third right position; when the oil pressure of the hydraulic control end C1 is equal to the oil pressure of the hydraulic control end C2, the arm balance valve 24 is located in the third middle position. In other embodiments, the arm balance valve 24 can also be an electrically controlled valve.

[0100] The hydraulic system in which the actuators are completely decoupled also includes a first boom holding valve 29 and a first boom pilot valve 30. The first boom holding valve 29 has a second pump side interface and a second cylinder side interface. The first boom holding valve 29 is connected in series to the first boom oil circuit 25 through the second pump side interface and the second cylinder side interface, and the second cylinder side interface is close to the boom rodless chamber 202 relative to the second pump side interface. The first boom holding valve 29 has a second open state and a second closed state. When the first boom holding valve 29 is in the second open state, the second pump side interface and the second cylinder side interface are connected. When the first boom holding valve 29 is in the second closed state, the second pump side interface and the second cylinder side interface are disconnected. When the first boom holding valve 29 is in the second closed state, when the oil pressure at the second pump side interface exceeds the second set value of the oil pressure at the second cylinder side interface, the first boom holding valve 29 can be switched to the second open state, or the first boom holding valve 29 can be controlled to switch to the second open state by the first boom pilot valve 30. By setting the first boom holding valve 29, when the first boom holding valve 29 is closed, the position of the boom piston rod can be stabilized, thereby maintaining the boom position stable; when the first boom holding valve 29 is in the second closed state, if it is necessary to supply oil to the boom rodless chamber 202, when the oil pressure of the second pump side interface exceeds the second set value of the oil pressure of the second cylinder side interface, under the action of the oil pressure difference, the first boom holding valve 29 can be switched to the second open state by itself without affecting the oil supply; if the oil pressure of the second pump side interface does not exceed the second set value of the oil pressure of the second cylinder side interface, the first boom holding valve 29 can be controlled to switch to the second open state by the first boom pilot valve 30; when the first boom holding valve 29 is in the second closed state, if it is necessary to discharge the oil in the boom rodless chamber 202, the first boom holding valve 29 can be controlled to switch to the second open state by the first boom pilot valve 30.

[0101] Optionally, the hydraulic system in which the actuators are completely decoupled also includes a second boom holding valve 32 and a second boom pilot valve 33, the second boom holding valve 32 having a third pump side interface and a third cylinder side interface, the second boom holding valve 32 being connected in series to the second boom oil circuit 26 via the third pump side interface and the third cylinder side interface, and the third cylinder side interface is close to the boom with a rod chamber 201 relative to the third pump side interface, the second boom holding valve 32 having a third open state and a third closed state, when the second boom holding valve 32 is in the third open state, the third pump side interface and the third cylinder side interface are connected, when the second boom holding valve 32 is in the third closed state, the third pump side interface and the third cylinder side interface are disconnected; when the second boom holding valve 32 is in the third closed state: when the oil pressure at the third pump side interface exceeds the third set value of the oil pressure at the third cylinder side interface, the second boom holding valve 32 can be switched to the third open state, or the second boom pilot valve 33 can be used to control the second boom holding valve 32 to switch to the third open state. By setting the second boom holding valve 32, when the second boom holding valve 32 is closed, the position of the boom piston rod can be stabilized, thereby maintaining the boom position stable; when the second boom holding valve 32 is in the third closed state, if it is necessary to supply oil to the boom rod chamber 201, when the oil pressure of the third pump side interface exceeds the third set value of the oil pressure of the third cylinder side interface, under the action of the oil pressure difference, the second boom holding valve 32 can be switched to the third open state by itself without affecting the oil supply; if the oil pressure of the third pump side interface does not exceed the third set value of the oil pressure of the third cylinder side interface, the second boom holding valve 32 can be controlled to switch to the third open state by the second boom pilot valve 33; when the second boom holding valve 32 is in the third closed state, if it is necessary to discharge the oil in the boom rod chamber 201, the second boom pilot valve 33 can be used to control the second boom holding valve 32 to switch to the third open state.

[0102] Specifically, the structure of the first boom holding valve 29 and the structure of the second boom holding valve 32 are the same as the structure of the first boom holding valve 14, and will not be repeated here. The structure of the first boom pilot valve 30 and the structure of the second boom pilot valve 33 are the same as the structure of the first boom pilot valve 15, and will not be repeated here. The hydraulic system with all decoupled actuators also includes a third electromagnetic switch valve 31 for controlling the on-off of the oil circuit of the hydraulic control end of the first boom pilot valve 30, and the on-off of the signal oil source of the first boom pilot valve 30 can be controlled by the third electromagnetic switch valve 31 to achieve switching control of the working position of the first boom pilot valve 30. The hydraulic system with all decoupled actuators also includes a fourth electromagnetic switch valve 34 for controlling the on-off of the oil circuit of the hydraulic control end of the second boom pilot valve 33, and the on-off of the signal oil source of the second boom pilot valve 33 can be controlled by the fourth electromagnetic switch valve 34 to achieve switching control of the working position of the second boom pilot valve 33.

[0103] Optionally, the hydraulic system in which all actuators are decoupled also includes a boom control valve 35, which is arranged in the first boom oil circuit 25, and the boom control valve 35 is located between the first boom holding valve 29 and the first boom oil pump 23, and the boom control valve 35 is used to open or close the first boom oil circuit 25; the boom control valve 35 is configured to open the first boom oil circuit 25 when the first boom pilot valve 30 controls the first boom holding valve 29 to switch to the second open state, or when the second boom pilot valve 33 controls the second boom holding valve 32 to switch to the third open state. It is understandable that when the boom piston rod of the boom cylinder 2 is extended and retracted, the oil in the two chambers of the boom cylinder 2 needs to flow in and out, and the first boom holding valve 29 and the second boom holding valve 32 must be in the open state at the same time. One of the boom holding valves can be opened by the differential pressure between the pump side interface and the cylinder side interface being greater than the set value, and the other needs to be opened by the boom pilot valve control, so that the boom control valve 35 is opened synchronously. When the position of the boom piston rod needs to remain unchanged, the first boom holding valve 29 and the second boom holding valve 32 are both kept closed. At this time, the boom control valve 35 disconnects the first boom oil circuit 25, which can further improve the stability of the boom piston rod position.

[0104] Specifically, in this embodiment, the arm control valve 35 is also a hydraulically controlled valve, and the valve core of the arm control valve 35 can move in the valve housing of the arm control valve 35 to have a fourth left position, a fourth middle position, and a fourth right position. When the arm control valve 35 is located at the fourth left position and the fourth right position, the arm control valve 35 connects the first arm oil circuit 25, and when the arm control valve 35 is located at the fourth middle position, the arm control valve 35 disconnects the first arm oil circuit 25.

[0105] The boom control valve 35 includes a hydraulic control end D1 and a hydraulic control end D2. The third electromagnetic switch valve 31 is also used to control the on-off of the oil circuit of the hydraulic control end D1. The fourth electromagnetic switch valve 34 is also used to control the on-off of the oil circuit of the hydraulic control end D2. The hydraulic control end D1 and the hydraulic control end D2 are respectively located on both sides of the valve core of the boom control valve 35, and the oil of the hydraulic control end D1 and the hydraulic control end D2 directly acts on the valve core of the boom control valve 35. The force of the oil of the hydraulic control end D1 acting on the valve core of the boom control valve 35 and the force of the oil of the hydraulic control end D2 acting on the valve core of the boom control valve 35 are compared to determine the stop position of the valve core of the boom control valve 35.

[0106] Optionally, the hydraulic system with all actuators decoupled also includes a third oil replenishment check valve 36 and a fourth oil replenishment check valve 37, the third oil replenishment check valve 36 is connected between the oil replenishment circuit 6 and the boom rodless chamber 202, and the third oil replenishment check valve 36 only allows oil to flow from the oil replenishment circuit 6 to the boom rodless chamber 202, specifically, the third oil replenishment check valve 36 is connected between the oil replenishment circuit 6 and the first boom oil circuit 25; the fourth oil replenishment check valve 37 is connected between the oil replenishment circuit 6 and the boom rod chamber 201, and the fourth oil replenishment check valve 37 only allows oil to flow from the oil replenishment circuit 6 to the boom rod chamber 201, specifically, the fourth oil replenishment check valve 37 is connected between the oil replenishment circuit 6 and the second boom oil circuit 26. By setting the third oil replenishment check valve 36, when the oil pressure in the arm rodless chamber 202 is low, the oil can be replenished to the arm rodless chamber 202 through the oil replenishment oil circuit 6; by setting the fourth oil replenishment check valve 37, when the oil pressure in the arm rod chamber 201 is low, the oil can be replenished to the arm rod chamber 201 through the oil replenishment oil circuit 6 to further balance the flow difference between the arm rod chamber 201 and the arm rodless chamber 202. Specifically, the connection between the third oil replenishment check valve 36 and the first arm oil circuit 25 is located between the arm holding valve and the arm cylinder 2.

[0107] Optionally, the hydraulic system in which the actuators are completely decoupled also includes a third overflow valve 38 and a fourth overflow valve 39, the third overflow valve 38 is connected between the oil replenishment circuit 6 and the first boom oil circuit 25, and the third overflow valve 38 only allows oil to overflow from the boom rodless chamber 202 through the first boom oil circuit 25 to the oil replenishment circuit 6. Specifically, the connection between the third overflow valve 38 and the first boom oil circuit 25 is located between the boom holding valve and the boom cylinder 2; the fourth overflow valve 39 is connected between the oil replenishment circuit 6 and the second boom oil circuit 26, and the fourth overflow valve 39 only allows oil to overflow from the boom rod chamber 201 through the second boom oil circuit 26 to the oil replenishment circuit 6. By setting the third overflow valve 38 and the fourth overflow valve 39, excessive oil pressure in the boom rod chamber 201 and the boom rodless chamber 202 can be effectively avoided.

[0108] Optionally, the hydraulic system with all actuators decoupled further includes a boom regeneration valve 40, which is configured to connect the first boom oil circuit 25 and the second boom oil circuit 26, or disconnect the first boom oil circuit 25 and the second boom oil circuit 26. Specifically, the connection between the boom regeneration valve 40 and the first boom oil circuit 25 is located between the boom control valve 35 and the first boom holding valve 29. When the boom regeneration valve 40 is opened, the oil can flow directly between the boom rodless chamber 202 and the boom rod chamber 201, and flow from the side with high pressure to the side with low pressure, so that the boom piston rod can move quickly.

[0109] Optionally, the boom regeneration valve 40 is a two-position two-way hydraulically controlled valve, and the hydraulic system in which all actuators are decoupled further includes a regeneration control valve 41 , which is used to control the connection and disconnection of a signal oil circuit of the boom regeneration valve 40 .

[0110] Please refer to Figure 5 and Figure 6 The hydraulic system with all decoupled actuators also includes a first bucket oil pump 42 and a bucket balance valve 43. One end of the first bucket oil pump 42 is connected to the first bucket oil circuit 44, and the other end of the first bucket oil pump 42 is connected to the second bucket oil circuit 45. The first bucket oil circuit 44 is connected to the bucket rodless chamber 302, and the second bucket oil circuit 45 is connected to the bucket rod chamber 301. The first bucket oil pump 42 forms a bucket hydraulic circuit with two chambers of the bucket cylinder 3 through the first bucket oil circuit 44 and the second bucket oil circuit 45. The bucket balance valve 43 is configured to connect the one with smaller oil pressure in the first bucket oil circuit 44 and the second bucket oil circuit 45 to the oil replenishment circuit 6. Since the cross-sectional areas of the bucket rod chamber 301 and the bucket rodless chamber 302 are different, there is a flow difference. When the first bucket oil pump 42 drives the oil to flow between the bucket rod chamber 301 and the bucket rodless chamber 302, the flow difference can be balanced by the bucket balance valve 43, and the oil temperature in the oil replenishing circuit 6 is relatively low, and the hot oil in the bucket hydraulic circuit can be replaced with the low-temperature oil in the oil replenishing circuit, which can ensure the normal oil temperature in the bucket hydraulic circuit, and then ensure the normal operation of the bucket cylinder 3. Compared with the existing technology, there is no need to configure temperature monitoring, and it can also effectively reduce costs.

[0111] In this embodiment, the first bucket oil pump 42 adopts a closed pump. The first bucket oil pump 42 can rotate forward and reverse. Compared with an open pump, it can significantly reduce the energy loss of the system. The bucket oil cylinder 3 is supplied with oil by the first bucket oil pump 42, so that the bucket oil pump can be decoupled, thereby improving the controllability of the bucket oil circuit.

[0112] Optionally, the hydraulic system with all actuators decoupled further includes a second bucket oil pump 46, one end of which is connected to the oil replenishment circuit 6, and the other end of which is connected to the third bucket oil circuit 47, which is connected to the first bucket oil circuit 44. The second bucket oil pump 46 is only used to supply oil to the bucket rodless chamber 302 or drain oil at the same time as the first bucket oil pump 42, so as to further balance the flow difference between the bucket rod chamber 301 and the bucket rodless chamber 302.

[0113] In this embodiment, the second bucket oil pump 46 can also rotate forward and reverse, and the second bucket oil pump 46 adopts a closed pump. Specifically, both the first bucket oil pump 42 and the second bucket oil pump 46 can adopt a quantitative pump.

[0114] In this embodiment, the bucket piston rod can move relative to the bucket cylinder body and have a third extended position and a third retracted position. When the bucket piston rod moves to the third extended position, the bucket piston rod gradually extends to the outside, and the first bucket oil pump 42 rotates forward and pumps the oil in the bucket rod chamber 301 into the bucket rodless chamber 302. However, due to the flow difference between the bucket rod chamber 301 and the bucket rodless chamber 302, it is also necessary to use the second bucket oil pump 46 to simultaneously pump the oil in the oil replenishment circuit 6 into the bucket rodless chamber 302 to compensate for the flow difference. At this time, the second bucket oil pump 46 also rotates forward. If the bucket piston rod is subjected to a positive load at this time, and the oil pressure in the bucket rod chamber 301 is less than the oil pressure in the bucket rodless chamber 302, the bucket balance valve 43 connects the second bucket oil circuit 45 and the oil replenishing circuit 6. If the bucket piston rod is subjected to a negative load at this time, and the oil pressure in the bucket rod chamber 301 is greater than the oil pressure in the bucket rodless chamber 302, the bucket balance valve 43 connects the first bucket oil circuit 44 and the oil replenishing circuit 6.

[0115] When the bucket piston rod moves to the third retracted position, the bucket piston rod gradually retracts inward, the first bucket oil pump 42 rotates in the opposite direction, and pumps a part of the oil in the bucket rodless chamber 302 into the bucket rod chamber 301. At the same time, the second bucket oil pump 46 rotates in the opposite direction, and the second bucket oil pump 46 pumps another part of the oil in the bucket rodless chamber 302 to the oil replenishing circuit 6. If the bucket piston rod is subjected to a positive load at this time, the oil pressure in the bucket rod chamber 301 is greater than the oil pressure in the bucket rodless chamber 302, then the bucket balance valve 43 connects the first bucket oil circuit 44 and the oil replenishing circuit 6. If the bucket piston rod is subjected to a negative load at this time, the oil pressure in the bucket rod chamber 301 is less than the oil pressure in the bucket rodless chamber 302, then the bucket balance valve 43 connects the second bucket oil circuit 45 and the oil replenishing circuit 6.

[0116] Specifically, in this embodiment, the bucket balance valve 43 includes a P3 interface, an A 31 Interface and A 32 Interface, among which, the P3 interface is connected to the oil replenishment line 6, A 31 The interface is connected to the first bucket oil circuit 44, A 32 The bucket balance valve 43 has a fourth left position and a fourth right position. When the bucket balance valve 43 is in the fourth left position, the bucket balance valve 43 makes the P3 interface and A communicate with each other. 32 The interface is connected and A 31 The interface is disconnected, so that the oil supply oil circuit 6 is connected to the second bucket oil circuit 45, and the first bucket oil circuit 44 is disconnected; when the bucket balance valve 43 is in the fourth right position, the bucket balance valve 43 makes the P3 interface and A 31 The interface is connected and A 32The interface is disconnected, so that the oil supply oil circuit 6 is connected to the first bucket oil circuit 44, and the second bucket oil circuit 45 is disconnected. Preferably, the bucket balance valve 43 also has a fourth middle position. When the bucket balance valve 43 is in the fourth middle position, the P3 interface is disconnected, A 31 The interface is disconnected and A 32 The interface is disconnected, thereby disconnecting the oil replenishment circuit 6 from the first bucket oil circuit 44 and the second bucket oil circuit 45 at the same time.

[0117] In the present embodiment, the bucket balancing valve 43 is specifically a hydraulically controlled valve, and the bucket balancing valve 43 has a hydraulic control end E1 and a hydraulic control end E2. The hydraulic control end E1 is connected to the first bucket oil circuit 44, and the hydraulic control end E2 is connected to the second bucket oil circuit 45. The hydraulic control end E1 and the hydraulic control end E2 are respectively located on both sides of the valve core of the bucket balancing valve 43, and the oil of the hydraulic control end E1 and the hydraulic control end E2 directly acts on the valve core of the bucket balancing valve 43. The force of the oil of the hydraulic control end E1 acting on the valve core of the bucket balancing valve 43 and the force of the oil of the hydraulic control end E2 acting on the valve core of the bucket balancing valve 43 are compared to determine the stop position of the valve core of the bucket balancing valve 43. Specifically, when the oil pressure of the hydraulic control end E1 is greater than the oil pressure of the hydraulic control end E2, the bucket balance valve 43 is located in the fourth left position; when the oil pressure of the hydraulic control end E1 is less than the oil pressure of the hydraulic control end E2, the bucket balance valve 43 is located in the fourth right position; when the oil pressure of the hydraulic control end E1 is equal to the oil pressure of the hydraulic control end E2, the bucket balance valve 43 is located in the fourth middle position. In other embodiments, the bucket balance valve 43 can also be an electrically controlled valve.

[0118] The hydraulic system in which all actuators are decoupled also includes a first bucket holding valve 48 and a first bucket pilot valve 49. The first bucket holding valve 48 has a fourth pump side interface and a fourth cylinder side interface. The first bucket holding valve 48 is connected in series to the first bucket oil circuit 44 through the fourth pump side interface and the fourth cylinder side interface, and the fourth cylinder side interface is close to the dipper rodless chamber 202 relative to the fourth pump side interface. The first bucket holding valve 48 has a fourth open state and a fourth closed state. When the first bucket holding valve 48 is in the fourth open state, the fourth pump side interface and the fourth cylinder side interface are connected. When the first bucket holding valve 48 is in the fourth closed state, the fourth pump side interface and the fourth cylinder side interface are disconnected. When the first bucket holding valve 48 is in the fourth closed state, when the oil pressure at the fourth pump side interface exceeds the fourth set value of the oil pressure at the fourth cylinder side interface, the first bucket holding valve 48 is switched to the fourth open state, or the first bucket pilot valve 49 is used to control the first bucket holding valve 48 to switch to the fourth open state. By setting the first bucket holding valve 48, when the first bucket holding valve 48 is closed, the position of the bucket piston rod can be stabilized, thereby maintaining the bucket position stable; when the first bucket holding valve 48 is in the fourth closed state, if it is necessary to supply oil to the dipper rodless chamber 202, when the oil pressure of the fourth pump side interface exceeds the fourth set value of the oil pressure of the fourth cylinder side interface, under the action of the oil pressure difference, the first bucket holding valve 48 can be switched to the fourth open state by itself without affecting the oil supply; if the oil pressure of the fourth pump side interface does not exceed the fourth set value of the oil pressure of the fourth cylinder side interface, the first bucket pilot valve 49 can be used to control the first bucket holding valve 48 to switch to the fourth open state; when the first bucket holding valve 48 is in the fourth closed state, if it is necessary to discharge the oil in the dipper rodless chamber 202, the first bucket pilot valve 49 can be used to control the first bucket holding valve 48 to switch to the fourth open state.

[0119] Optionally, the hydraulic system in which the actuators are completely decoupled also includes a second bucket holding valve 51 and a second bucket pilot valve 52, the second bucket holding valve 51 having a fifth pump side interface and a fifth cylinder side interface, the second bucket holding valve 51 being connected in series to the second bucket oil circuit 45 via the fifth pump side interface and the fifth cylinder side interface, and the fifth cylinder side interface having a rod chamber 201 close to the dipper rod relative to the fifth pump side interface, the second bucket holding valve 51 having a fifth open state and a fifth closed state, when the second bucket holding valve 51 is in the fifth open state, the fifth pump side interface and the fifth cylinder side interface are connected, when the second bucket holding valve 51 is in the fifth closed state, the fifth pump side interface and the fifth cylinder side interface are disconnected; when the second bucket holding valve 51 is in the fifth closed state, when the oil pressure at the fifth pump side interface exceeds the fifth set value of the oil pressure at the fifth cylinder side interface, the second bucket holding valve 51 can be switched to the fifth open state, or the second bucket pilot valve 52 can be used to control the second bucket holding valve 51 to switch to the fifth open state. By setting the second bucket holding valve 51, when the second bucket holding valve 51 is closed, the position of the bucket piston rod can be stabilized, thereby maintaining the bucket position stable; when the second bucket holding valve 51 is in the fifth closed state, if it is necessary to supply oil to the dipper rod chamber 201, when the oil pressure of the fifth pump side interface exceeds the fifth set value of the oil pressure of the fifth cylinder side interface, under the action of the oil pressure, the second bucket holding valve 51 can be switched to the fifth open state by itself without affecting the oil supply; if the oil pressure of the fifth pump side interface does not exceed the fifth set value of the oil pressure of the fifth cylinder side interface, the second bucket holding valve 51 can be controlled to switch to the fifth open state by the second bucket pilot valve 52; when the second bucket holding valve 51 is in the fifth closed state, if it is necessary to discharge the oil in the dipper rod chamber 201, the second bucket holding valve 51 can be controlled to switch to the fifth open state by the second bucket pilot valve 52.

[0120] Specifically, the structures of the first bucket holding valve 48 and the second bucket holding valve 51 are the same as those of the first boom holding valve 14, and will not be described in detail here. The structures of the first bucket pilot valve 49 and the second bucket pilot valve 52 are the same as those of the first boom pilot valve 15, and will not be described in detail here. The hydraulic system with all decoupled actuators also includes a fifth electromagnetic switch valve 50 for controlling the on-off of the oil circuit of the hydraulic control end of the first bucket pilot valve 49, and the on-off of the signal oil source of the first bucket pilot valve 49 can be controlled by the fifth electromagnetic switch valve 50 to achieve the switching control of the working position of the first bucket pilot valve 49. The hydraulic system with all decoupled actuators also includes a sixth electromagnetic switch valve 53 for controlling the on-off of the oil circuit of the hydraulic control end of the second bucket pilot valve 52, and the on-off of the signal oil source of the second bucket pilot valve 52 can be controlled by the sixth electromagnetic switch valve 53 to achieve the switching control of the working position of the second bucket pilot valve 52.

[0121] Optionally, the hydraulic system in which the actuators are completely decoupled also includes a bucket control valve 54, which is arranged in the first bucket oil circuit 44, and the bucket control valve 54 is located between the first bucket holding valve 48 and the first bucket oil pump 42, and the bucket control valve 54 is used to open or close the first bucket oil circuit 44; the bucket control valve 54 is configured to open the first bucket oil circuit 44 when the first bucket pilot valve 49 controls the first bucket holding valve 48 to switch to the second open state, or when the second bucket pilot valve 52 controls the second bucket holding valve 51 to switch to the third open state. It is understandable that when the boom piston rod of the boom cylinder 2 is extended and retracted, the oil in the two chambers of the boom cylinder 2 needs to flow in and out, and the first bucket holding valve 48 and the second bucket holding valve 51 must be in the open state at the same time. One of the bucket holding valves can be opened by the differential pressure between the pump side interface and the cylinder side interface being greater than the set value, and the other needs to be opened by the bucket pilot valve control, thereby making the bucket control valve 54 open synchronously. When the position of the boom piston rod needs to remain unchanged, the first bucket holding valve 48 and the second bucket holding valve 51 are both kept closed. At this time, the bucket control valve 54 disconnects the first bucket oil circuit 44, which can further improve the stability of the boom piston rod position.

[0122] Specifically, in this embodiment, the bucket control valve 54 is also a hydraulically controlled valve, and the valve core of the bucket control valve 54 can move in the valve housing of the bucket control valve 54 to have a fourth left position, a fourth middle position, and a fourth right position. When the bucket control valve 54 is located at the fourth left position and the fourth right position, the bucket control valve 54 connects the first bucket oil circuit 44, and when the bucket control valve 54 is located at the fourth middle position, the bucket control valve 54 disconnects the first bucket oil circuit 44.

[0123] The bucket control valve 54 includes a hydraulic control end G1 and a hydraulic control end G2. The fifth electromagnetic switch valve 50 is also used to control the on-off of the oil circuit of the hydraulic control end G1. The sixth electromagnetic switch valve 53 is also used to control the on-off of the oil circuit of the hydraulic control end G2. The hydraulic control end G1 and the hydraulic control end G2 are respectively located on both sides of the valve core of the bucket control valve 54, and the oil of the hydraulic control end G1 and the hydraulic control end G2 directly acts on the valve core of the bucket control valve 54. The force of the oil of the hydraulic control end G1 acting on the valve core of the bucket control valve 54 and the force of the oil of the hydraulic control end G2 acting on the valve core of the bucket control valve 54 are compared to determine the stop position of the valve core of the bucket control valve 54.

[0124] Optionally, the hydraulic system in which the actuators are completely decoupled also includes a fifth oil replenishment check valve 55 and a sixth oil replenishment check valve 56, the fifth oil replenishment check valve 55 is connected between the oil replenishment circuit 6 and the bucket rodless chamber 302, and the fifth oil replenishment check valve 55 only allows oil to flow from the oil replenishment circuit 6 to the bucket rodless chamber 302, specifically, the fifth oil replenishment check valve 55 is connected between the oil replenishment circuit 6 and the first bucket oil circuit 44; the sixth oil replenishment check valve 56 is connected between the oil replenishment circuit 6 and the bucket rod chamber 301, and the sixth oil replenishment check valve 56 only allows oil to flow from the oil replenishment circuit 6 to the bucket rod chamber 301, specifically, the sixth oil replenishment check valve 56 is connected between the oil replenishment circuit 6 and the second bucket oil circuit 45. By providing the fifth oil replenishment check valve 55, when the oil pressure in the bucket rodless chamber 302 is low, the oil can be replenished to the bucket rodless chamber 302 through the oil replenishment oil circuit 6; by providing the sixth oil replenishment check valve 56, when the oil pressure in the bucket rod chamber 301 is low, the oil can be replenished to the bucket rod chamber 301 through the oil replenishment oil circuit 6, so as to further balance the flow difference between the bucket rod chamber 301 and the bucket rodless chamber 302. Specifically, the connection between the fifth oil replenishment check valve 55 and the first bucket oil circuit 44 is located between the bucket holding valve and the bucket cylinder 3.

[0125] Optionally, the hydraulic system in which the actuators are completely decoupled also includes a fifth overflow valve 57 and a sixth overflow valve 58. The fifth overflow valve 57 is connected between the oil replenishment circuit 6 and the first bucket oil circuit 44, and the fifth overflow valve 57 only allows oil to overflow from the bucket rodless chamber 302 through the first bucket oil circuit 44 to the oil replenishment circuit 6. Specifically, the connection between the fifth overflow valve 57 and the first bucket oil circuit 44 is located between the bucket holding valve and the bucket cylinder 3; the sixth overflow valve 58 is connected between the oil replenishment circuit 6 and the second bucket oil circuit 45, and the sixth overflow valve 58 only allows oil to overflow from the bucket rod chamber 301 through the second bucket oil circuit 45 to the oil replenishment circuit 6. By setting the fifth overflow valve 57 and the sixth overflow valve 58, excessive oil pressure in the bucket rod chamber 301 and the bucket rodless chamber 302 can be effectively avoided.

[0126] Optionally, the hydraulic system with all actuators decoupled further includes a bucket regeneration valve 59, which is configured to connect the first bucket oil circuit 44 and the second bucket oil circuit 45, or disconnect the first bucket oil circuit 44 and the second bucket oil circuit 45. Specifically, the connection between the bucket regeneration valve 59 and the first bucket oil circuit 44 is located between the bucket control valve 54 and the first bucket holding valve 48. When the bucket regeneration valve 59 is opened, the oil can flow directly between the bucket rodless chamber 302 and the bucket rod chamber 301, and flow from the side with high pressure to the side with low pressure, so that the bucket piston rod can move quickly.

[0127] The present invention also provides an excavator, which includes the above-mentioned boom decoupling hydraulic system, the excavator also includes an excavator body, a boom hinged to the excavator body, a boom hinged to the boom, and a bucket hinged to the boom, the boom cylinder body of the boom cylinder 1 is hinged to the excavator body, the boom piston rod of the boom cylinder 1 is hinged to the boom, the boom cylinder body of the boom cylinder 2 is hinged to the boom, the boom piston rod of the boom cylinder 2 is hinged to the boom, the bucket cylinder body of the bucket cylinder 3 is hinged to the boom, and the bucket piston rod of the bucket cylinder 3 is hinged to the bucket. The excavator can realize boom decoupling and optimize the thermal balance arm of the boom decoupling hydraulic system.

[0128] Optionally, the excavator also includes a drive system, which is an extended-range drive system, a pure electric drive system or a hybrid drive system.

[0129] Please refer to Figure 7 When the drive system is a pure electric drive system, the drive system includes a first motor 60, a second motor 61, a third motor 62 and a battery 63. Among them, the first motor 60 can rotate forward and reverse, and the first motor 60 is respectively connected to the first boom oil pump 8 and the second boom oil pump 12, and the first motor 60 can simultaneously drive the first boom oil pump 8 and the second boom oil pump 12 to rotate; the second motor 61 is respectively connected to the first dipper arm oil pump 23 and the second dipper arm oil pump 27, and the second motor 61 can simultaneously drive the first dipper arm oil pump 23 and the second dipper arm oil pump 27 to rotate; the third motor 62 is respectively connected to the first bucket oil pump 42 and the second bucket oil pump 46, and the third motor 62 can simultaneously drive the first bucket oil pump 42 and the second bucket oil pump 46 to rotate. The use of a pure electric drive system can effectively reduce the complexity of system control, improve system controllability, and improve system efficiency.

[0130] In this embodiment, the rotation speed of the first motor 60 is controlled to control the extension and retraction speed of the boom piston rod of the boom cylinder 1. Moreover, when the boom piston rod is retracted, the boom is lowered by its own weight, and the first boom oil pump 8 and / or the second boom oil pump 12 drives the first motor 60 to reverse, which can generate electricity and store it in the battery 63, thereby realizing the recycling of system energy.

[0131] Please refer to Figure 8When the driving system is an extended-range driving system, the driving system includes a first motor 60 , a second motor 61 , a third motor 62 , a battery 63 , a first internal combustion engine 64 and a first generator 65 . Among them, the first motor 60 can rotate forward and reverse, and the first motor 60 is respectively connected to the first boom oil pump 8 and the second boom oil pump 12, and the first motor 60 can simultaneously drive the first boom oil pump 8 and the second boom oil pump 12 to rotate; the second motor 61 is respectively connected to the first bucket oil pump 23 and the second bucket oil pump 27, and the second motor 61 can simultaneously drive the first bucket oil pump 23 and the second bucket oil pump 27 to rotate; the third motor 62 is respectively connected to the first bucket oil pump 42 and the second bucket oil pump 46, and the third motor 62 can simultaneously drive the first bucket oil pump 42 and the second bucket oil pump 46 to rotate, and the battery 63 is respectively electrically connected to the first motor 60, the second motor 61, the third motor 62 and the oil replenishment motor 71; the first internal combustion engine 64 is connected to the first generator 65 and is used to drive the first generator 65 to rotate, and the first generator 65 is electrically connected to the battery 63. The use of the extended-range drive system can avoid the problem of relying solely on the battery 63 for power supply, and the whole machine needs to be limited by the maximum storage capacity of the battery 63.

[0132] Please refer to Fig. 9 When the drive system is a hybrid drive system, the drive system includes a first motor 60, a second internal combustion engine 66, a fuel replenishment motor 71, a second generator 67 and a battery 63. The first motor 60 can rotate forward and reverse, and the first motor 60 is simultaneously connected to the first boom oil pump 8 and the second boom oil pump 12, and the first motor 60 can simultaneously drive the first boom oil pump 8 and the second boom oil pump 12 to rotate; the second internal combustion engine 66 is respectively connected to the first arm oil pump 23, the second arm oil pump 27, the first bucket oil pump 42, the second bucket oil pump 46 and the second generator 67, and the second internal combustion engine 66 is used to drive the first arm oil pump 23, the second arm oil pump 27, the first bucket oil pump 42 and the second bucket oil pump 46 to rotate simultaneously, and drive the second generator 67 to generate electricity; the fuel replenishment motor 71 is connected to the fuel replenishment pump 4, and the fuel replenishment motor 71 is used to drive the fuel replenishment pump 4 to rotate; the battery 63 is respectively electrically connected to the first motor 60, the fuel replenishment motor 71 and the second generator 67. Compared with a pure electric drive system, the hybrid drive system does not need to be limited by the maximum storage capacity of the battery 63; compared with an extended-range drive system, the number of motors can be effectively reduced.

[0133] Optionally, the drive system further includes a slewing motor 68, a left travel motor 69 and a right travel motor 70. The slewing motor 68 is used to drive the slewing mechanism of the excavator, and the left travel motor 69 and the right travel motor 70 are used to drive the left travel mechanism and the right travel mechanism of the excavator, respectively. Such an arrangement can decouple the slewing operation, the left travel control operation and the right travel control operation of the excavator. Among them, the battery 63 also supplies power to the slewing motor 68, the left travel motor 69 and the right travel motor 70, respectively.

[0134] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A hydraulic system with fully decoupled actuators, comprising a boom cylinder (1), an arm cylinder (2) and a bucket cylinder (3), wherein the boom cylinder (1) comprises a boom rod chamber (101) and a boom rodless chamber (102) with variable volumes, the arm cylinder (2) comprises an arm rod chamber (201) and an arm rodless chamber (202) with variable volumes, and the bucket cylinder (3) comprises a bucket rod chamber (301) and a bucket rodless chamber (302) with variable volumes, characterized in that: The hydraulic system in which all actuators are decoupled further comprises: An oil replenishment pump (4), one end of which is connected to the oil tank (5) and the other end of which is connected to the oil replenishment circuit (6); A first boom oil pump (8), one end of which is connected to a first boom oil circuit (10) and the other end of which is connected to a second boom oil circuit (11), wherein the first boom oil circuit (10) is connected to the boom rodless chamber (102), and the second boom oil circuit (11) is connected to the boom rod chamber (101); A boom balancing valve (9) is configured to connect the one with a smaller oil pressure between the first boom oil circuit (10) and the second boom oil circuit (11) to the oil replenishment circuit (6); A first boom oil pump (23), one end of which is connected to a first boom oil circuit (25) and the other end of which is connected to a second boom oil circuit (26), wherein the first boom oil circuit (25) is connected to the boom non-rod chamber (202) and the second boom oil circuit (26) is connected to the boom rod chamber (201); The boom balancing valve (24) is configured to connect the one with the lower oil pressure between the first boom oil circuit (25) and the second boom oil circuit (26) to the oil replenishment circuit (6); A first bucket oil pump (42), one end of which is connected to a first bucket oil circuit (44) and the other end of which is connected to a second bucket oil circuit (45), wherein the first bucket oil circuit (44) is connected to the bucket rodless chamber (302) and the second bucket oil circuit (45) is connected to the bucket rod chamber (301); The bucket balancing valve (43) is configured to connect the one with the smaller oil pressure between the first bucket oil circuit (44) and the second bucket oil circuit (45) to the oil replenishment circuit (6).

2. The hydraulic system with fully decoupled actuators according to claim 1, characterized in that: The hydraulic system in which all actuators are decoupled further comprises: A second boom oil pump (12) has one end connected to the oil replenishment circuit (6) and the other end connected to a third boom oil circuit (13); the third boom oil circuit (13) is connected to the first boom oil circuit (10).

3. The hydraulic system with fully decoupled actuators according to claim 2, characterized in that: The hydraulic system in which all actuators are decoupled further comprises a boom holding valve (14) and a boom pilot valve (15), wherein the boom holding valve (14) has a first pump side interface and a first cylinder side interface, wherein the boom holding valve (14) is connected in series to the first boom oil circuit (10) via the first pump side interface and the first cylinder side interface, and the first cylinder side interface is closer to the boom rodless chamber (102) relative to the first pump side interface, and the boom holding valve (14) has a first open state and a first closed state, wherein when the boom holding valve (14) is in the first open state, the first pump side interface and the first cylinder side interface are connected, and when the boom holding valve (14) is in the first closed state, the first pump side interface and the first cylinder side interface are disconnected; When the boom holding valve (14) is in the first closed state, the oil pressure at the first pump side interface exceeds the first set value of the oil pressure at the first cylinder side interface, so that the boom holding valve (14) can be switched to the first open state, or the boom pilot valve (15) controls the boom holding valve (14) to switch to the first open state.

4. The hydraulic system with fully decoupled actuators according to claim 2, characterized in that: The hydraulic system in which all actuators are decoupled further comprises a boom control valve (17) arranged in the first boom oil circuit (10); the boom control valve (17) is arranged in the first boom oil circuit (10), and the boom control valve (17) is located between the connection between the third boom oil circuit (13) and the first boom oil circuit (10) and the first boom oil pump (8); the boom control valve (17) is used to open or close the first boom oil circuit (10).

5. The hydraulic system with fully decoupled actuators according to claim 1, characterized in that: The hydraulic system in which all actuators are decoupled further comprises: A second boom oil pump (27) has one end connected to the oil replenishment circuit (6) and the other end connected to a third boom oil circuit (28), and the third boom oil circuit (28) is connected to the first boom oil circuit (25).

6. The hydraulic system with fully decoupled actuators according to claim 5, characterized in that: The hydraulic system in which the actuator is completely decoupled further comprises a first boom holding valve (29) and a first boom pilot valve (30), wherein the first boom holding valve (29) has a second pump side interface and a second cylinder side interface, the first boom holding valve (29) is connected in series to the first boom oil circuit (25) via the second pump side interface and the second cylinder side interface, and the second cylinder side interface is closer to the boom rodless chamber (202) relative to the second pump side interface, the first boom holding valve (29) has a second open state and a second closed state, when the first boom holding valve (29) is in the second open state, the second pump side interface and the second cylinder side interface are connected, and when the first boom holding valve (29) is in the second closed state, the second pump side interface and the second cylinder side interface are disconnected; When the first boom holding valve (29) is in the second closed state, the oil pressure at the second pump side interface exceeds the second set value of the oil pressure at the second cylinder side interface, so that the first boom holding valve (29) can be switched to the second open state, or the first boom pilot valve (30) controls the first boom holding valve (29) to switch to the second open state.

7. The hydraulic system with fully decoupled actuators according to claim 6, characterized in that: The hydraulic system in which all actuators are decoupled further comprises: a second boom holding valve (32) and a second boom pilot valve (33), wherein the second boom holding valve (32) has a third pump side interface and a third cylinder side interface, the second boom holding valve (32) is connected in series to the second boom oil circuit (26) via the third pump side interface and the third cylinder side interface, and the third cylinder side interface is provided with a rod chamber (201) near the boom relative to the third pump side interface, the second boom holding valve (32) has a third open state and a third closed state, when the second boom holding valve (32) is in the third open state, the third pump side interface and the third cylinder side interface are connected, and when the second boom holding valve (32) is in the third closed state, the third pump side interface and the third cylinder side interface are disconnected; When the second boom holding valve (32) is in the third closed state, the oil pressure at the third pump side interface exceeds the third set value of the oil pressure at the third cylinder side interface, so that the second boom holding valve (32) switches to the third open state, or the second boom pilot valve (33) controls the second boom holding valve (32) to switch to the third open state.

8. The hydraulic system with fully decoupled actuators according to claim 7, characterized in that: The hydraulic system in which all actuators are decoupled further comprises an arm control valve (35), wherein the arm control valve (35) is arranged in the first arm oil circuit (25), and the arm control valve (35) is located between the connection point between the third arm oil circuit (28) and the first arm oil circuit (25) and the first arm oil pump (23), and the arm control valve (35) is used to open or close the first arm oil circuit (25); The boom control valve (35) is configured to open the first boom oil circuit (25) when the first boom pilot valve (30) controls the first boom holding valve (29) to switch to the second open state, or when the second boom pilot valve (33) controls the second boom holding valve (32) to switch to the third open state.

9. The hydraulic system with fully decoupled actuators according to any one of claims 5 to 8, characterized in that: The hydraulic system in which all actuators are decoupled further comprises a boom regeneration valve (40), wherein the boom regeneration valve (40) is configured to connect the first boom oil circuit (25) and the second boom oil circuit (26), or to disconnect the first boom oil circuit (25) and the second boom oil circuit (26).

10. The hydraulic system with fully decoupled actuators according to claim 1, characterized in that: The hydraulic system in which all actuators are decoupled further comprises: A second bucket oil pump (46) has one end connected to the oil replenishment circuit (6) and the other end connected to a third bucket oil circuit (47), and the third bucket oil circuit (47) is connected to the first bucket oil circuit (44).

11. The hydraulic system with fully decoupled actuators according to claim 10, characterized in that: The hydraulic system in which the actuator is completely decoupled also includes a first bucket holding valve (48) and a first bucket pilot valve (49), the first bucket holding valve (48) having a fourth pump side interface and a fourth cylinder side interface, the first bucket holding valve (48) being connected in series to the first bucket oil circuit (44) via the fourth pump side interface and the fourth cylinder side interface, and the fourth cylinder side interface being closer to the bucket rodless chamber (302) relative to the fourth pump side interface, the first bucket holding valve (48) having a fourth open state and a fourth closed state, when the first bucket holding valve (48) is in the fourth open state, the fourth pump side interface and the fourth cylinder side interface are connected, and when the first bucket holding valve (48) is in the fourth closed state, the fourth pump side interface and the fourth cylinder side interface are disconnected; When the first bucket holding valve (48) is in the fourth closed state, the oil pressure at the fourth pump side interface exceeds the fourth set value of the oil pressure at the fourth cylinder side interface, so that the first bucket holding valve (48) can be switched to the fourth open state, or the first bucket pilot valve (49) controls the first bucket holding valve (48) to switch to the fourth open state.

12. The hydraulic system with fully decoupled actuators according to claim 11, characterized in that: The hydraulic system in which the actuator is completely decoupled further comprises a second bucket holding valve (51) and a second bucket pilot valve (52), wherein the second bucket holding valve (51) has a fifth pump side interface and a fifth cylinder side interface, the second bucket holding valve (51) is connected in series to the second bucket oil circuit (45) via the fifth pump side interface and the fifth cylinder side interface, and the fifth cylinder side interface is close to the bucket rod cavity (301) relative to the fifth pump side interface, the second bucket holding valve (51) has a fifth open state and a fifth closed state, when the second bucket holding valve (51) is in the fifth open state, the fifth pump side interface and the fifth cylinder side interface are connected, and when the second bucket holding valve (51) is in the fifth closed state, the fifth pump side interface and the fifth cylinder side interface are disconnected; When the second bucket holding valve (51) is in the fifth closed state, the oil pressure at the fifth pump side interface exceeds the fifth set value of the oil pressure at the fifth cylinder side interface, so that the second bucket holding valve (51) switches to the fifth open state, or the second bucket pilot valve (52) controls the second bucket holding valve (51) to switch to the fifth open state.

13. The hydraulic system with fully decoupled actuators according to claim 12, characterized in that: The hydraulic system with all actuators decoupled further comprises a bucket control valve (54), the bucket control valve (54) being arranged in the first bucket oil circuit (44), and the bucket control valve (54) being located between a connection point between the third bucket oil circuit (47) and the first bucket oil circuit (44) and the first bucket oil pump (42), the bucket control valve (54) being used to open or close the first bucket oil circuit (44); The bucket control valve (54) is configured to open the first bucket oil circuit (44) when the first bucket pilot valve (49) controls the first bucket holding valve (48) to switch to the fourth open state, or when the second bucket pilot valve (52) controls the second bucket holding valve (51) to switch to the fifth open state.

14. The hydraulic system with fully decoupled actuators according to any one of claims 10 to 13, characterized in that: The hydraulic system in which all actuators are decoupled further comprises a bucket regeneration valve (59), wherein the bucket regeneration valve (59) is configured to connect the first bucket oil circuit (44) and the second bucket oil circuit (45) to each other, or to disconnect the first bucket oil circuit (44) and the second bucket oil circuit (45) from each other.

15. An excavator, characterized in that: A hydraulic system comprising a completely decoupled actuator as described in any one of claims 1 to 14, wherein the excavator further comprises an excavator body, a boom hinged to the excavator body, a dipper arm hinged to the boom, and a bucket hinged to the dipper arm, the boom cylinder body of the boom cylinder (1) being hinged to the excavator body, the boom piston rod of the boom cylinder (1) being hinged to the boom, the dipper arm cylinder body of the dipper arm cylinder (2) being hinged to the boom, the dipper arm piston rod of the dipper arm cylinder (2) being hinged to the dipper arm, the bucket cylinder body of the bucket cylinder (3) being hinged to the dipper arm, and the bucket piston rod of the bucket cylinder (3) being hinged to the bucket.

16. The excavator according to claim 15, characterized in that: The excavator also includes a drive system, which is an extended-range drive system, a pure electric drive system or a hybrid drive system.

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