Auxiliary operation system of hydraulic excavator

Abstract

The invention relates to an auxiliary operation system of a hydraulic excavator, which belongs to the technical field of excavator engineering and comprises a first pump, an oil outlet of which is connected with an oil inlet of a rotary valve core through a first oil path; an oil outlet of the second pump is connected with an oil inlet of the first movable arm valve element through a second oil way; a first working oil port and a second working oil port of the first movable arm valve element are connected with a rodless cavity and a rod cavity of the movable arm oil cylinder respectively. The first oil way is connected with a first branch, the first branch is connected with a second movable arm valve element, and an oil outlet of the second movable arm valve element is connected to an oil way between a second working oil port of the first movable arm valve element and the rodless cavity through a third oil way; the third oil way is connected with a second branch and a third branch, the second branch is connected with a movable arm potential energy unloading valve, and the third branch is connected with a movable arm potential energy regeneration valve. The first pump, the second pump, the second movable arm valve element, the movable arm potential energy unloading valve, the movable arm potential energy regeneration valve and the movable arm potential energy regeneration stop valve can cooperatively control rotation and movable arm composite motion of the excavator.

Description

Technical Field

[0001] The invention relates to a hydraulic excavator auxiliary operation system and belongs to the technical field of excavator engineering. Background Art

[0002] Excavators often complete compound actions. When loading, the most common action is the compound action of slewing + boom lifting, slewing + boom lowering. When adjusting the loading height of a traditional excavator, it is necessary to add a throttle hole in the middle of the oil circuit of the boom valve core and the slewing valve core to achieve the distribution of the boom flow and the slewing flow. However, with this throttle hole, the boom loading height will become different at different engine speeds, or according to the preset control strategy, the compound movement of slewing + boom lifting is difficult to be in place at the same time to meet the actual needs of the operator for adjusting the excavator posture. At the same time, when the excavator returns to the excavation state after loading the car, the most common action is the compound action of boom lowering + slewing, and the boom lowering can be completed by its own weight. In order to prevent the boom from descending too fast, it is often necessary to increase the back pressure of the boom lowering valve core to limit the speed. When the boom is lowered, the regeneration flow of the boom cylinder is difficult to be recycled, resulting in energy loss. At the same time, the compound movement of slewing + boom lowering is also difficult to be in place at the same time, and the flexibility and applicability of the operation are poor. Summary of the invention

[0003] The object of the present invention is to provide a hydraulic excavator auxiliary operation system, which coordinates the control of the excavator's rotation + boom compound motion through a first pump, a second pump, a second boom valve core, a boom potential energy unloading valve, a boom potential energy regeneration valve, and a boom potential energy regeneration cut-off valve, so as to achieve the purpose that the compound action of rotation + boom lifting can more coordinately meet the operator's actual needs for the excavator posture.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions to achieve: In a first aspect, the present invention provides a hydraulic excavator auxiliary operation system, comprising: a first pump, wherein an oil outlet of the first pump is connected to an oil inlet of the rotary valve core through a first oil circuit; a second pump, wherein the oil outlet of the second pump is connected to the oil inlet of the first boom valve core through a second oil circuit; the first working oil port and the second working oil port of the first boom valve core are respectively connected to the rodless chamber and the rod chamber of the boom cylinder; the oil return port of the first boom valve core is connected to the oil tank; The first oil circuit is connected to a first branch, the first branch is connected to the oil inlet of the second boom valve core, and the oil outlet of the second boom valve core is connected to the oil circuit between the second working oil port of the first boom valve core and the rodless chamber of the boom oil cylinder through a third oil circuit. Optionally, the third oil circuit is connected with a second branch and a third branch, the second branch is connected to the oil inlet of the boom potential energy unloading valve, the oil return port of the boom potential energy unloading valve is connected to the oil tank, the third branch is connected to the oil inlet of the boom potential energy regeneration valve, and the oil outlet of the boom potential energy regeneration valve is connected to the first oil circuit downstream of the first branch; the oil outlet of the boom potential energy regeneration valve is also connected to the oil inlet of the boom potential energy regeneration cut-off valve, and the oil outlet of the boom potential energy regeneration cut-off valve is connected to the oil tank; the opening of the second boom valve core, boom potential energy unloading valve, boom potential energy regeneration valve and boom potential energy regeneration cut-off valve can all be controlled by a control valve.

[0005] Optionally, the first boom valve core includes an ascending working position and a descending working position; When the first boom valve core is in the ascending working position, the oil inlet of the first boom valve core is connected with the second working oil port, and the first working oil port of the first boom valve core is connected with the oil return port; When the first boom valve core is in the descending working position, the oil inlet of the first boom valve core is communicated with the first working oil port, and the second working oil port of the first boom valve core is communicated with the oil return port.

[0006] Optionally, when the first boom valve core is in the rising working position and the second boom valve core is connected, the hydraulic oil output by the first pump can supply oil to the rodless chamber of the boom cylinder through the second boom valve core and the third oil circuit; when the first boom valve core is in the falling working position, the hydraulic oil withdrawn from the rodless chamber of the boom cylinder can flow to the second branch or the third branch through the third oil circuit.

[0007] Optionally, both the first oil circuit and the first branch circuit are provided with a one-way valve to form a one-way flow.

[0008] Optionally, it further comprises a third pump, a first control valve, a first reversing valve and a second control valve; the oil outlet of the third pump is connected to the oil inlet of the first control valve, the first oil port of the first control valve is connected to the oil inlet of the second control valve, and the oil outlet of the second control valve is connected to the control oil circuit; when the second control valve is in the left position, the oil inlet and the oil outlet of the second control valve are connected, and when the second control valve is in the right position, the oil inlet and the oil outlet of the second control valve are cut off; the second oil port of the first control valve is connected to the control end of the first reversing valve; the oil inlet of the first control valve can be connected to the first oil port or the second oil port; The oil inlet and oil outlet of the first reversing valve are respectively connected to the oil outlet of the second pump and the oil tank; the first reversing valve includes a left position and a right position; the right end of the first reversing valve serves as a control end; when the first reversing valve is in the left position, the oil inlet and oil outlet of the first reversing valve are disconnected, and when the first reversing valve is in the right position, the oil inlet and oil outlet of the first reversing valve are connected.

[0009] Optionally, the oil outlet of the third pump is further connected to a first overflow valve, and the oil outlets of the first pump and the second pump are connected to the same second overflow valve.

[0010] Optionally, it also includes a second reversing valve, the oil inlet of the second reversing valve is connected to the oil outlet of the first pump, the oil outlet of the second reversing valve is connected to the oil tank, and the second reversing valve includes a left position and a right position; when the second reversing valve is in the left position, the oil inlet and the oil outlet of the second reversing valve are connected, and when the second reversing valve is in the right position, the oil inlet and the oil outlet of the second reversing valve are cut off; the left end of the second reversing valve is connected to a ninth solenoid valve.

[0011] Optionally, the control ends of the second boom valve core, the boom potential energy unloading valve, the boom potential energy regeneration valve, and the boom potential energy regeneration cut-off valve are respectively connected to the first solenoid valve, the second solenoid valve, the third solenoid valve, and the fourth solenoid valve; the left and right ends of the rotary valve core are respectively connected to the fifth solenoid valve and the sixth solenoid valve, when the fifth solenoid valve is energized, the rotary valve core is in the left position, and when the sixth solenoid valve is energized, the rotary valve core is in the right position; by switching the position of the rotary valve core, the rotation direction of the rotary motor connected to the rotary valve core can be changed; the left and right ends of the first boom valve core are respectively connected to the seventh solenoid valve and the eighth solenoid valve; the oil inlets of the first solenoid valve, the second solenoid valve, the third solenoid valve and the fourth solenoid valve, the fifth solenoid valve and the sixth solenoid valve, the seventh solenoid valve and the eighth solenoid valve are all connected to the control oil circuit.

[0012] Optionally, a first pressure sensor and a second pressure sensor are respectively provided at the oil outlets of the first pump and the second pump.

[0013] In a second aspect, the present invention provides an excavator, which includes the hydraulic excavator auxiliary operation.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. During use, the auxiliary operation system of the present invention can coordinately control the rotation and boom compound motion of the excavator through the first pump, the second pump, the second boom valve core, the boom potential energy unloading valve, the boom potential energy regeneration valve, and the boom potential energy regeneration cut-off valve, so that the compound action of rotation + boom lifting can more coordinately meet the operator's actual needs for the excavator posture.

[0015] 2. When the boom is lifted and rotated in a combined motion, the present invention can adjust the flow rates of the first pump and the second pump according to the actual rotation range and boom height requirements, thereby being able to control the rotation speed and the boom lifting speed respectively, so that the boom is lifted to the expected height while rotating into place. Among them, the first pump mainly controls the rotation speed. However, while controlling the rotation, the first pump can also affect the boom flow rate through the second boom valve core and the third oil circuit, so as to achieve multi-mode adjustment of the boom speed.

[0016] 3. The third oil circuit of the present invention not only plays a role in regulating the boom flow rate during the composite movement of boom raising and rotating; during the composite movement of boom lowering and rotating, the rotation speed and boom speed can still be adjusted by adjusting the flow rates of the first pump and the second pump in terms of control; at the same time, the boom potential energy unloading valve, boom potential energy regeneration valve, and boom potential energy regeneration cut-off valve connected to the third oil circuit can also be used for control. Specifically, by controlling the boom potential energy regeneration valve and the boom potential energy regeneration cut-off valve to utilize the regenerated flow rate brought by the boom lowering potential energy to speed up the rotation speed, the boom lowering speed can also be adjusted by adjusting the boom potential energy unloading valve to adjust the back pressure of the boom lowering, thereby realizing multi-mode composite movement regulation, thereby satisfying the operator's flexibility and coordination requirements for composite movements as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the hydraulic system in the present invention.

[0018] Numbers in the figure: 1, first solenoid valve; 2, second solenoid valve; 3, third solenoid valve; 4, fourth solenoid valve; 5, fifth solenoid valve; 6, sixth solenoid valve; 7, swing motor; 8, boom oil cylinder; 9, swing valve core; 10, boom potential energy unloading valve; 11. Boom potential energy regeneration valve; 12. First boom valve core; 13. Seventh solenoid valve; 14. Eighth solenoid valve; 15. Second control valve; 16. First overflow valve; 17. First control valve; 18. First reversing valve; 19. Boom potential energy regeneration cut-off valve; 20. Second boom valve core; 21. Second reversing valve; 22. First pressure sensor; 23. First pump; 24. Second overflow valve; 25. Second pressure sensor; 26. Second pump; 27. Third pump; 28. Ninth solenoid valve. DETAILED DESCRIPTION

[0019] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions 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", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. 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 by specific circumstances.

[0020] Among the prior art known to the inventors of the present application, existing hydraulic excavators usually need to perform a compound action of rotation and boom. Usually, a preset control strategy is built into the hydraulic system of the excavator, and the control strategy can enable the boom to reach a preset height while the excavator completes the rotation, which is equivalent to presetting a stroke trajectory of a compound action. However, from the operator's perspective, the flexibility of this control strategy is poor, because the required rotation angle and the required boom height are variable during actual use. The compound action under the preset control strategy is difficult to meet the coordination expected by the operator (that is, when the required rotation angle is in place, the boom also reaches the required height), which brings inconvenience to the operator.

[0021] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention. Example 1

[0022] Combination Figure 1The present embodiment provides a hydraulic excavator auxiliary operation system, which includes a first pump 23 and a second pump 26; the oil outlet of the first pump 23 is connected to the oil inlet of the rotary valve core 9 through a first oil circuit; the oil outlet of the second pump 26 is connected to the oil inlet of the first boom valve core 12 through a second oil circuit; the first working oil port and the second working oil port of the first boom valve core 12 are respectively connected to the rodless chamber and the rod chamber of the boom cylinder 8; the oil return port of the first boom valve core 12 is connected to the oil tank; the first oil circuit is connected with a first branch, the first branch is connected to the oil inlet of the second boom valve core 20, and the oil outlet of the second boom valve core 20 is connected to the second working oil port of the first boom valve core 12 and the boom cylinder 8 through a third oil circuit. On the oil circuit between the rodless chambers; the third oil circuit is connected with the second branch and the third branch, the second branch is connected to the oil inlet of the boom potential energy unloading valve 10, the oil return port connected to the boom potential energy unloading valve 10 is connected to the oil tank, the third branch is connected to the oil inlet of the boom potential energy regeneration valve 11, and the oil outlet of the boom potential energy regeneration valve 11 is connected to the first oil circuit downstream of the first branch; the oil outlet of the boom potential energy regeneration valve 11 is also connected to the oil inlet of the boom potential energy regeneration cut-off valve 19, and the oil outlet of the boom potential energy regeneration cut-off valve 19 is connected to the oil tank; the opening of the second boom valve core 20, the boom potential energy unloading valve 10, the boom potential energy regeneration valve 11, and the boom potential energy regeneration cut-off valve 19 can all be controlled by the control valve.

[0023] The first boom valve core 12 includes an ascending working position and a descending working position; when the first boom valve core 12 is in the ascending working position, the oil inlet of the first boom valve core 12 is connected with the second working oil port, and the first working oil port of the first boom valve core 12 is connected with the oil return port; when the first boom valve core 12 is in the descending working position, the oil inlet of the first boom valve core 12 is connected with the first working oil port, and the second working oil port of the first boom valve core 12 is connected with the oil return port.

[0024] The following describes the combined motion process of boom lifting and excavator rotation in combination with the oil flow direction.

[0025] When the first boom valve core 12 is in the rising working position: the hydraulic oil flowing out of the first pump 23 passes through the first oil circuit, the first branch circuit, the second boom valve core 20, the third oil circuit, the boom cylinder 8, the first boom valve core 12 in sequence and then flows back to the oil tank, and the hydraulic oil flowing out of the second pump 26 passes through the first boom valve core 12, the boom cylinder 8, the first boom valve core 12 in sequence and then flows back to the oil tank. The process of the boom cylinder 8 driving the boom to do the lifting movement is a well-known process in the art and will not be described in detail here; the hydraulic oil flowing out of the first pump 23 will also pass through the first oil circuit, the rotary valve core 9, the rotary motor 7, the rotary valve core 9 in sequence and then flow back to the oil tank.

[0026] Specifically, in the working process of the above oil circuit, the swing motor 7 is only supplied with oil through the first pump 23, so the swing speed of the excavator is mainly controlled by the first pump 23. Both the first pump 23 and the second pump 26 can supply oil to the boom cylinder 8, but in actual operation, the boom cylinder 8 is mainly supplied with oil through the second pump 26, and the first pump 23 and the first boom valve core 12 can play an auxiliary role. The second pump 26 will make corresponding adjustments according to the flow change of the first pump 23 to control the boom movement. The third oil circuit for the first pump 23 to supply oil to the boom cylinder 8 is mainly used for control when the boom is lowered.

[0027] Furthermore, in this embodiment, the first pump 23 and the second pump 26 are mainly used to supply oil to the swing motor 7 and the boom cylinder 8 respectively, and the maximum flow of the first pump 23 and the second pump 26 is determined by the engine speed. If the engine speed decreases, the maximum flow of the first pump 23 and the second pump 26 will decrease, so the first pump 23 and the second pump 26 need to use a large flow state (which can be understood as more than 80% of the maximum flow) for output.

[0028] Specifically, the excavator generally controls the main pump (the first pump 23 and the second pump 26) by power, that is, power = pressure × flow rate, because the pressure can be identified only by the sensor, which is simple and easy. The flow rate requires the addition of a flow sensor, which is complicated to assemble and costly. Therefore, when the power is known, the controller will convert it into flow rate through pressure identification. For example: if the customer sets the lifting height of the boom to be higher, the controller will give the main pump (the second pump 26) that controls the lifting of the boom a larger flow rate, so that the lifting speed of the boom will be faster; if the customer sets the lifting height of the boom to be lower, the controller will give the main pump (the second pump 26) that controls the lifting of the boom a smaller flow rate, so that the lifting speed of the boom will be slower; the control principle of increasing and decreasing the rotation distance is similar, so I will not elaborate on it here.

[0029] Specifically, the first pump 23 and the second pump 26 are respectively provided with a first pressure sensor 22 and a second pressure sensor 25 for identifying pressure at the oil outlets. The pressure signals identified by the first pressure sensor 22 and the second pressure sensor 25 are used to distribute the flow of the first pump 23 and the second pump 26. For example, in the rotation start-up stage, the rotation pressure is large, and the flow of the first pump controlling the rotation is increased accordingly.

[0030] Therefore, in the actual operation process, the flow mode of the first pump 23 and the second pump 26 is firstly adaptively adjusted according to the engine speed. At the same time, when performing the compound action of rotation and boom lifting, if the rotation range is reduced (increased) compared with the rotation range of the preset control strategy, the rotation speed can be reduced (increased) by reducing (increasing) the flow of the first pump 23 to achieve adaptive adjustment. If the boom height is reduced (increased) compared with the height of the preset control strategy, the boom speed can be reduced (increased) by reducing (increasing) the flow of the second pump 26 to achieve adaptive adjustment. Through such a control strategy, the rotation range and the boom height can be adjusted according to actual needs, and the control goal is that the boom reaches the required height at the same time as the rotation is in place. This embodiment is based on the auxiliary operation system can realize the flexible adaptation of the compound action of rotation and boom lifting through the flow control of the first pump 23 and the second pump 26, so as to meet the operator's expectations for the coordination of the compound movement of rotation and boom.

[0031] Back to the adjustment of the valve core position of the first boom valve core 12, when the first boom valve core 12 is in the descending working position: the hydraulic oil output by the second pump 26 passes through the first boom valve core 12 in turn to reach the boom cylinder 8, and the hydraulic oil in the rod chamber of the boom cylinder 8 will be regenerated to or flow to the rodless chamber of the boom cylinder 8, and the excess hydraulic oil flows back to the hydraulic oil tank after passing through the first boom valve core 12, thereby causing energy waste. Based on this problem, when the first boom valve core 12 is in the descending working position, this embodiment can form a boom potential energy cross-circuit regeneration oil circuit, a boom potential energy regeneration cut-off oil circuit and a boom potential energy unloading oil circuit by introducing a boom potential energy unloading valve 10, a boom potential energy regeneration valve 11 and a boom potential energy regeneration cut-off valve 19.

[0032] The boom potential energy cross-circuit regeneration oil circuit is specifically as follows: the hydraulic oil flowing out of the rodless chamber of the boom cylinder 8 passes through the third oil circuit, the third branch, the boom potential energy regeneration valve 11, the rotary valve core 9, the rotary motor 7, and the rotary valve core 9 in sequence and then flows back to the oil tank, thereby utilizing the regenerated flow to drive the rotary motor 7 to move.

[0033] The boom potential energy regeneration cut-off oil circuit is specifically as follows: the hydraulic oil flowing out of the rodless chamber of the boom cylinder 8 passes through the third oil circuit, the third branch, the boom potential energy regeneration valve 11, and the boom potential energy regeneration cut-off valve 19 in sequence and then flows back to the oil tank, thereby cutting off the oil circuit between the regeneration flow and the rotary valve core 9.

[0034] The boom potential energy unloading oil circuit is specifically as follows: the hydraulic oil flowing out of the rodless cavity of the boom cylinder 8 passes through the third oil circuit, the second branch circuit, the boom potential energy unloading valve 10 in sequence and then flows back to the oil tank.

[0035] Specifically, the present embodiment, by adding a third oil circuit and a boom potential energy unloading valve 10, a boom potential energy regeneration valve 11, and a boom potential energy regeneration cut-off valve 19, can utilize the regeneration flow brought by the boom potential energy by controlling the opening of the boom potential energy regeneration valve 11, and can also coordinate with the first pump 23 to control the rotation speed using the recovered regeneration flow to achieve adaptive adjustment; by controlling the opening of the boom potential energy regeneration cut-off valve 19, the flow rate of the regeneration flow used to drive the rotation motor 7 can be further controlled; by controlling the opening of the boom potential energy unloading valve 10, the back pressure of the boom descent can be adjusted to adjust the boom descent speed, thereby coordinating with the second pump 26 to control the boom speed to achieve adaptive adjustment.

[0036] In conjunction with the compound motion of swinging and boom lowering, if the swing range is reduced (increased) compared to the preset control strategy, the total flow of the first pump 23 and the regeneration flow to the swing motor 7 (controlled by the boom potential energy regeneration valve 11 and the boom potential energy regeneration cut-off valve 19) is adaptively reduced (increased) to meet the operator's swing requirements. If the boom height is reduced (increased) compared to the preset control strategy, the boom speed can still be adjusted by controlling the flow of the second pump 26 to be reduced (increased), or the back pressure of the boom lowering can be increased (reduced) by reducing (increasing) the opening of the boom potential energy unloading valve 10, thereby achieving adaptive adjustment of the boom speed.

[0037] In general, the auxiliary operation system provided based on this embodiment can adaptively adjust the combined motion of rotation and boom in multiple ways by controlling the flow of the first pump 23, the flow of the second pump 26, the opening of the boom potential energy unloading valve 10, the opening of the boom potential energy regeneration valve 11, and the opening of the boom potential energy regeneration cut-off valve 19, thereby meeting the driver's needs for coordination or flexibility of the combined motion.

[0038] In a specific embodiment, both the first oil circuit and the first branch circuit are provided with a one-way valve to form a one-way flow to prevent the hydraulic oil from flowing back.

[0039] In another specific embodiment, the auxiliary operation system further includes a third pump 27, a first control valve 17, a first reversing valve 18 and a second control valve 15; the oil outlet of the third pump 27 is connected to the oil inlet of the first control valve 17, the first oil port of the first control valve 17 is connected to the oil inlet of the second control valve 15, and the oil outlet of the second control valve 15 is connected to the control oil circuit; when the second control valve 15 is in the left position, the oil inlet and the oil outlet of the second control valve 15 are connected, and when the second control valve 15 is in the right position, the oil inlet and the oil outlet of the second control valve 15 are cut off; The second oil port of the first control valve 17 is connected to the control end of the first reversing valve 18; the oil inlet of the first control valve 17 can be communicated with the first oil port or the second oil port; the oil inlet and oil outlet of the first reversing valve 18 are respectively connected to the oil outlet of the second pump 26 and the oil tank; the first reversing valve 18 includes a left position and a right position; the right end of the first reversing valve 18 serves as the control end; when the first reversing valve 18 is in the left position, the oil inlet and oil outlet of the first reversing valve 18 are disconnected, and when the first reversing valve 18 is in the right position, the oil inlet and oil outlet of the first reversing valve 18 are connected.

[0040] The third pump 27 mainly supplies oil to the control oil circuit through the first control valve 17 and the second control valve 15 to control the opening of the second boom valve core 20, the boom potential energy unloading valve 10, the boom potential energy regeneration valve 11, and the boom potential energy regeneration cut-off valve 19.

[0041] In addition, when the second pump 26 is not working, the first reversing valve 18 can be switched to the right position, so that the oil outlet of the second pump 26 is directly connected to the oil tank, so as to reduce the power of the second pump 26 and achieve energy saving.

[0042] In another specific embodiment, the auxiliary operation system also includes a second reversing valve 21, the oil inlet of the second reversing valve 21 is connected to the oil outlet of the first pump 23, the oil outlet of the second reversing valve 21 is connected to the oil tank, and the second reversing valve 21 includes a left position and a right position; when the second reversing valve 21 is in the left position, the oil inlet and the oil outlet of the second reversing valve 21 are connected, and when the second reversing valve 21 is in the right position, the oil inlet and the oil outlet of the second reversing valve 21 are cut off; the left end of the second reversing valve 21 is connected to a ninth solenoid valve 28.

[0043] When the first pump 23 is not working, the second reversing valve 21 can be switched to the left position, so that the oil outlet of the first pump 23 is directly connected to the mailbox to reduce the power of the first pump 23 and achieve energy saving.

[0044] In a specific embodiment, the control ends of the second boom valve core 20, the boom potential energy unloading valve 10, the boom potential energy regeneration valve 11, and the boom potential energy regeneration cut-off valve 19 are respectively connected to the first solenoid valve 1, the second solenoid valve 2, the third solenoid valve 3, and the fourth solenoid valve 4; the left and right ends of the rotary valve core 9 are respectively connected to the fifth solenoid valve 5 and the sixth solenoid valve 6, when the fifth solenoid valve 5 is energized, the rotary valve core 9 is in the left position, and when the sixth solenoid valve 6 is energized, the rotary valve core 9 is in the right position; by switching the position of the rotary valve core 9, the rotation direction of the rotary motor 7 connected to the rotary valve core 9 can be changed; the first boom valve The left and right ends of the core 12 are respectively connected to the seventh solenoid valve 13 and the eighth solenoid valve 14; the oil inlets of the first solenoid valve 1, the second solenoid valve 2, the third solenoid valve 3 and the fourth solenoid valve 4, the fifth solenoid valve 5 and the sixth solenoid valve 6, the seventh solenoid valve 13 and the eighth solenoid valve 14 are all connected to the control oil circuit, and the third pump 27 can provide hydraulic oil for the control oil circuit, so that the first solenoid valve 1, the second solenoid valve 2, the third solenoid valve 3 and the fourth solenoid valve 4, the fifth solenoid valve 5 and the sixth solenoid valve 6, the seventh solenoid valve 13 and the eighth solenoid valve 14 can output hydraulic oil to the corresponding control end to achieve shifting or opening control.

[0045] In addition, the oil outlet of the third pump 27 is also connected to the first overflow valve 16 to protect the oil circuit when the oil pressure is too high; the oil outlets of the first pump 23 and the second pump 26 are connected to the same second overflow valve 24 to protect the oil circuit when the oil pressure is too high. Example 2

[0046] This embodiment provides an excavator, which includes the hydraulic excavator auxiliary operation system described in Example 1.

[0047] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A hydraulic excavator auxiliary operation system, characterized in that: include: A first pump (23), the oil outlet of the first pump (23) being connected to the oil inlet of the rotary valve core (9) via a first oil circuit; a second pump (26), wherein the oil outlet of the second pump (26) is connected to the oil inlet of the first boom valve core (12) via a second oil circuit; the first working oil port and the second working oil port of the first boom valve core (12) are respectively connected to the rodless chamber and the rod chamber of the boom cylinder (8); and the oil return port of the first boom valve core (12) is connected to the oil tank; The first oil circuit is connected to a first branch circuit, the first branch circuit is connected to the oil inlet of the second boom valve core (20), and the oil outlet of the second boom valve core (20) is connected to the oil circuit between the second working oil port of the first boom valve core (12) and the rodless chamber of the boom cylinder (8) through a third oil circuit.

2. The hydraulic excavator auxiliary operation system according to claim 1, characterized in that: The third oil circuit is connected to a second branch, the second branch is connected to an oil inlet of a boom potential energy unloading valve (10), and the oil return port connected to the boom potential energy unloading valve (10) is connected to an oil tank.

3. The hydraulic excavator auxiliary operation system according to claim 1 or 2, characterized in that: The third oil circuit is connected to a third branch, the third branch is connected to an oil inlet of a boom potential energy regeneration valve (11), and the oil outlet of the boom potential energy regeneration valve (11) is connected to the first oil circuit downstream of the first branch.

4. The hydraulic excavator auxiliary operation system according to claim 3, characterized in that: The oil outlet of the boom potential energy regeneration valve (11) is also connected to the oil inlet of the boom potential energy regeneration cut-off valve (19), and the oil outlet of the boom potential energy regeneration cut-off valve (19) is connected to the oil tank.

5. The hydraulic excavator auxiliary operation system according to claim 1, characterized in that: The first boom valve core (12) comprises an ascending working position and a descending working position; When the first boom valve core (12) is in the ascending working position, the oil inlet of the first boom valve core (12) is communicated with the second working oil port, and the first working oil port of the first boom valve core (12) is communicated with the oil return port; When the first boom valve core (12) is in a descending working position, the oil inlet of the first boom valve core (12) is communicated with the first working oil port, and the second working oil port of the first boom valve core (12) is communicated with the oil return port.

6. The hydraulic excavator auxiliary operation system according to claim 5, characterized in that: When the first boom valve core (12) is in the ascending working position and the second boom valve core (20) is turned on, the hydraulic oil output by the first pump (23) can supply oil to the rodless chamber of the boom cylinder (8) through the second boom valve core (20) and the third oil circuit; when the first boom valve core (12) is in the descending working position, the hydraulic oil withdrawn from the rodless chamber of the boom cylinder (8) can flow to the second branch or the third branch through the third oil circuit.

7. The hydraulic excavator auxiliary operation system according to claim 1, characterized in that: The first oil circuit and the first branch circuit are both provided with a one-way valve to form a one-way flow.

8. The hydraulic excavator auxiliary operation system according to claim 1, characterized in that: It also comprises a third pump (27), a first control valve (17), a first reversing valve (18) and a second control valve (15); the oil outlet of the third pump (27) is connected to the oil inlet of the first control valve (17), the first oil port of the first control valve (17) is connected to the oil inlet of the second control valve (15), and the oil outlet of the second control valve (15) is connected to the control oil circuit.

9. The hydraulic excavator auxiliary operation system according to claim 8, characterized in that: When the second control valve (15) is in the left position, the oil inlet and the oil outlet of the second control valve (15) are connected; when the second control valve (15) is in the right position, the oil inlet and the oil outlet of the second control valve (15) are blocked; the second oil port of the first control valve (17) is connected to the control end of the first reversing valve (18); the oil inlet of the first control valve (17) can be connected to the first oil port or the second oil port.

10. The hydraulic excavator auxiliary operation system according to claim 9, characterized in that: The oil inlet and the oil outlet of the first reversing valve (18) are respectively connected to the oil outlet of the second pump (26) and the oil tank; the first reversing valve (18) comprises a left position and a right position; the right end of the first reversing valve (18) serves as a control end; when the first reversing valve (18) is in the left position, the oil inlet and the oil outlet of the first reversing valve (18) are disconnected; when the first reversing valve (18) is in the right position, the oil inlet and the oil outlet of the first reversing valve (18) are connected.

11. The hydraulic excavator auxiliary operation system according to claim 8, characterized in that: The oil outlet of the third pump (27) is also connected to a first overflow valve (16), and the oil outlets of the first pump (23) and the second pump (26) are connected to the same second overflow valve (24).

12. The hydraulic excavator auxiliary operation system according to claim 8, characterized in that: The invention also comprises a second reversing valve (21), wherein the oil inlet of the second reversing valve (21) is connected to the oil outlet of the first pump (23), and the oil outlet of the second reversing valve (21) is connected to the oil tank. The second reversing valve (21) comprises a left position and a right position. When the second reversing valve (21) is in the left position, the oil inlet and the oil outlet of the second reversing valve (21) are connected. When the second reversing valve (21) is in the right position, the oil inlet and the oil outlet of the second reversing valve (21) are blocked. The left end of the second reversing valve (21) is connected to a ninth solenoid valve (28).

13. The hydraulic excavator auxiliary operation system according to claim 12, characterized in that: The control ends of the second boom valve core (20), the boom potential energy unloading valve (10), the boom potential energy regeneration valve (11), and the boom potential energy regeneration cut-off valve (19) are respectively connected to the first solenoid valve (1), the second solenoid valve (2), the third solenoid valve (3), and the fourth solenoid valve (4); the left end and the right end of the rotary valve core (9) are respectively connected to the fifth solenoid valve (5) and the sixth solenoid valve (6); when the fifth solenoid valve (5) is energized, the rotary valve core (9) is in the left position; when the sixth solenoid valve (6) is energized, the rotary valve core (9) is in the left position. The invention is in the right position; by switching the position of the rotary valve core (9), the rotary direction of the rotary motor (7) connected to the rotary valve core (9) can be changed; the left end and the right end of the first boom valve core (12) are respectively connected to the seventh solenoid valve (13) and the eighth solenoid valve (14); the oil inlets of the first solenoid valve (1), the second solenoid valve (2), the third solenoid valve (3) and the fourth solenoid valve (4), the fifth solenoid valve (5) and the sixth solenoid valve (6), the seventh solenoid valve (13) and the eighth solenoid valve (14) are all connected to the control oil circuit.

14. The hydraulic excavator auxiliary operation system according to claim 1, characterized in that: A first pressure sensor (22) and a second pressure sensor (25) are respectively provided at the oil outlets of the first pump (23) and the second pump (26).

15. An excavator, characterized in that: It comprises the hydraulic excavator auxiliary operation system as described in any one of claims 1-14.

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