A hydraulic excavator auxiliary operation system

Abstract

This invention relates to an auxiliary operating system for a hydraulic excavator, belonging to the field of excavator engineering technology. It includes a first pump, whose outlet is connected to the inlet of a swing valve core via a first oil circuit; a second pump, whose outlet is connected to the inlet of a first boom valve core via a second oil circuit; the first and second working ports of the first boom valve core are respectively connected to the rodless and rod-side chambers of the boom cylinder; a first branch is connected to the first oil circuit, which in turn connects to a second boom valve core; the outlet of the second boom valve core is connected to the oil circuit between the second working port and the rodless chamber of the first boom valve core via a third oil circuit; the third oil circuit is connected to a second branch and a third branch, the second branch connecting to a boom potential energy unloading valve and the third branch connecting to a boom potential energy regeneration valve. The system can coordinately control the swing and boom combined motion of the excavator through the first pump, second pump, second boom valve core, boom potential energy unloading valve, boom potential energy regeneration valve, and boom potential energy regeneration shut-off valve.

Description

Technical Field

[0001] This invention relates to an auxiliary operating system for a hydraulic excavator, belonging to the field of excavator engineering technology. Background Technology

[0002] Excavators frequently perform complex maneuvers. During loading, the most common actions are swinging + boom lifting and swinging + boom lowering. Traditionally, adjusting the loading height of an excavator requires adding a throttle orifice between the boom and swing valves to distribute the flow of water between the boom and swing. However, this throttle orifice results in varying loading heights at different engine speeds. In other words, according to the preset control strategy, the swinging + boom lifting maneuvers are difficult to execute precisely at the same time to meet the operator's actual needs for adjusting the excavator's posture. Simultaneously, when the excavator returns to digging mode after loading, the most common action is boom lowering + swinging. While boom lowering can be accomplished by its own weight, to prevent excessively fast lowering, back pressure is often added to the boom lowering valve to limit the speed. This makes it difficult to recover and utilize the regenerative flow of the boom cylinder during lowering, resulting in energy loss. Furthermore, the swinging + boom lowering maneuvers are also difficult to execute precisely at the same time, leading to poor operational flexibility and applicability. Summary of the Invention

[0003] The purpose of this invention is to provide a hydraulic excavator auxiliary operation system that uses 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 shut-off valve to coordinately control the excavator's slewing and boom composite motion, so as to achieve a more coordinated slewing and boom lifting composite action that meets the operator's actual needs for the excavator's posture.

[0004] To achieve the above objectives, the present invention employs the following technical solution:

[0005] In a first aspect, the present invention provides a hydraulic excavator auxiliary operation system, comprising:

[0006] The first pump, the oil outlet of the first pump is connected to the oil inlet of the rotary valve core through the first oil passage;

[0007] The second pump has its outlet connected to the inlet of the first boom valve core via 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 return oil port of the first boom valve core is connected to the oil tank.

[0008] The first oil line is connected to a first branch line, which is connected to the oil inlet of the second boom valve core. The oil outlet of the second boom valve core is connected via a third oil line to the oil line between the second working oil port of the first boom valve core and the rodless chamber of the boom cylinder.

[0009] Optionally, the third oil line is connected to a second branch and a third branch. The second branch is connected to the inlet of the boom potential energy unloading valve, and the return port of the boom potential energy unloading valve is connected to the oil tank. The third branch is connected to the inlet of the boom potential energy regeneration valve, and the outlet of the boom potential energy regeneration valve is connected to the first oil line downstream of the first branch. The outlet of the boom potential energy regeneration valve is also connected to the inlet of the boom potential energy regeneration shut-off valve, and the outlet of the boom potential energy regeneration shut-off valve is connected to the oil tank. The opening degree of the second boom valve core, the boom potential energy unloading valve, the boom potential energy regeneration valve, and the boom potential energy regeneration shut-off valve can all be controlled by a control valve.

[0010] Optionally, the first boom valve core includes an upward working position and a downward working position;

[0011] When the first boom valve core is in the rising working position, the oil inlet of the first boom valve core is connected to the second working oil port, and the first working oil port of the first boom valve core is connected to the return oil port.

[0012] When the first boom valve core is in the lowered working position, the oil inlet of the first boom valve core is connected to the first working oil port, and the second working oil port of the first boom valve core is connected to the return oil port.

[0013] Optionally, when the first boom valve core is in the raised working position and the second boom valve core is open, 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 lowered working position, the hydraulic oil exiting from the rodless chamber of the boom cylinder can flow to the second branch or the third branch through the third oil circuit.

[0014] Optionally, both the first oil circuit and the first branch circuit are equipped with check valves to form unidirectional flow.

[0015] Optionally, it further includes a third pump, a first control valve, a first directional 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 a control oil circuit; when the second control valve is in the left position, the oil inlet and outlet of the second control valve are connected; when the second control valve is in the right position, the oil inlet and outlet of the second control valve are closed; the second oil port of the first control valve is connected to the control terminal of the first directional valve; the oil inlet of the first control valve can be connected to either the first oil port or the second oil port;

[0016] The inlet and outlet of the first directional valve are respectively connected to the outlet of the second pump and the oil tank; the first directional valve includes a left position and a right position; the right end of the first directional valve serves as the control end; when the first directional valve is in the left position, the inlet and outlet of the first directional valve are disconnected, and when the first directional valve is in the right position, the inlet and outlet of the first directional valve are connected.

[0017] Optionally, the oil outlet of the third pump is also 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.

[0018] Optionally, it also includes a second directional valve, the oil inlet of which is connected to the oil outlet of the first pump, and the oil outlet of which is connected to the oil tank. The second directional valve includes a left position and a right position. When the second directional valve is in the left position, the oil inlet and the oil outlet of the second directional valve are connected. When the second directional valve is in the right position, the oil inlet and the oil outlet of the second directional valve are closed. A ninth solenoid valve is connected to the left end of the second directional valve.

[0019] Optionally, the control terminals of the second boom valve core, boom potential energy unloading valve, boom potential energy regeneration valve, and boom potential energy regeneration shut-off valve are respectively connected to a first solenoid valve, a second solenoid valve, a third solenoid valve, and a fourth solenoid valve; the left and right ends of the rotary valve core are respectively connected to a fifth solenoid valve and a 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 a seventh solenoid valve and an eighth solenoid valve; the oil inlets of the first, second, third, fourth, fifth, sixth, seventh, and eighth solenoid valves are all connected to the control oil circuit.

[0020] Optionally, a first pressure sensor and a second pressure sensor are respectively provided at the oil outlet of the first pump and the second pump.

[0021] Secondly, the present invention provides an excavator that includes the aforementioned hydraulic excavator auxiliary operation.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The auxiliary operation system of the present invention can coordinate the control of the excavator’s slewing and boom composite motion 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 during use, so that the composite action of slewing + boom lifting can more coordinately meet the operator’s actual needs for the excavator’s posture.

[0024] 2. In the combined motion of boom lifting and slewing, this invention can adaptively adjust the flow rates of the first and second pumps according to the actual slewing range and boom height requirements, thereby controlling the slewing speed and boom lifting speed respectively, so that the boom is raised to the expected height at the same time as the slewing is completed. The first pump mainly controls the slewing speed, but while controlling the slewing, 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.

[0025] 3. In addition to regulating the boom flow rate during the combined boom lifting and slewing motions, the third hydraulic circuit of this invention also allows for control during the combined boom lowering and slewing motions. Firstly, the slewing speed and boom speed can still be adjusted by regulating the flow rates of the first and second pumps. Secondly, control can be achieved using the boom potential energy unloading valve, boom potential energy regeneration valve, and boom potential energy regeneration shut-off valve, all connected to the third hydraulic circuit. Specifically, by controlling the boom potential energy regeneration valve and the boom potential energy regeneration shut-off valve, the regenerated flow rate generated by the boom's descent potential energy can be utilized to accelerate the slewing speed. Furthermore, the boom potential energy unloading valve can be used to adjust the back pressure during boom descent, thereby adjusting the boom's descent speed. This multi-mode combined motion regulation aims to meet the operator's needs for flexibility and coordination in combined motions as much as possible. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the hydraulic system in this invention.

[0027] The following valves are labeled in the diagram: 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. Slewing motor; 8. Boom cylinder; 9. Slewing valve core; 10. Boom potential energy unloading valve.

[0028] 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 relief valve; 17. First control valve; 18. First directional valve; 19. Boom potential energy regeneration shut-off valve; 20. Second boom valve core; 21. Second directional valve; 22. First pressure sensor; 23. First pump; 24. Second relief valve; 25. Second pressure sensor; 26. Second pump; 27. Third pump; 28. Ninth solenoid valve. Detailed Implementation

[0029] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more. In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0030] In the prior art known to the inventors of this application, existing hydraulic excavators typically require a combined action of slewing and boom movement. The hydraulic system of an excavator usually has a built-in preset control strategy that ensures the boom reaches a preset height simultaneously with the excavator's slewing, essentially setting a trajectory for the combined action. However, from the operator's perspective, this control strategy lacks flexibility because the required slewing angle and boom height vary in actual use. The combined action under the preset control strategy struggles to meet the operator's desired coordination (i.e., the boom reaches the required height precisely when the required slewing angle is reached), causing inconvenience for the operator.

[0031] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention. Example 1

[0032] Combination Figure 1This 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; a first branch is connected to the first oil circuit, 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. The oil circuit between the rodless chambers; the third oil circuit is connected to 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 of 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, 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 shut-off valve 19, the oil outlet of the boom potential energy regeneration shut-off valve 19 is connected to the oil tank; the opening degree 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 shut-off valve 19 can all be controlled by the control valve.

[0033] The first boom valve core 12 includes a rising working position and a falling working position; when the first boom valve core 12 is in the rising working position, the oil inlet of the first boom valve core 12 is connected to the second working oil port, and the first working oil port of the first boom valve core 12 is connected to the return oil port; when the first boom valve core 12 is in the falling working position, the oil inlet of the first boom valve core 12 is connected to the first working oil port, and the second working oil port of the first boom valve core 12 is connected to the return oil port.

[0034] The following explanation focuses on the combined motion process of boom lifting and excavator rotation, taking into account the oil flow direction.

[0035] When the first boom valve spool 12 is in the raised working position: the hydraulic oil flowing out of the first pump 23 flows back to the oil tank after passing through the first oil circuit, the first branch circuit, the second boom valve spool 20, the third oil circuit, the boom cylinder 8, and the first boom valve spool 12 in sequence; the hydraulic oil flowing out of the second pump 26 flows back to the oil tank after passing through the first boom valve spool 12, the boom cylinder 8, and the first boom valve spool 12 in sequence. The process of the boom cylinder 8 driving the boom to perform lifting and lowering movements 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 flow back to the oil tank after passing through the first oil circuit, the slewing valve spool 9, the slewing motor 7, and the slewing valve spool 9 in sequence.

[0036] Specifically, during operation, the swing motor 7 is supplied with oil only through the first pump 23, therefore the excavator's swing speed is primarily 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 second pump 26 is primarily used. The first pump 23 and the first boom valve core 12 play an auxiliary role. The second pump 26 adjusts accordingly based on the flow rate changes of the first pump 23 to control the boom movement. The third oil circuit, where the first pump 23 supplies oil to the boom cylinder 8, is mainly used for boom descent control.

[0037] Furthermore, in this embodiment, the first pump 23 and the second pump 26 supply oil to the rotary motor 7 and the boom cylinder 8, respectively. The maximum flow rate of the first pump 23 and the second pump 26 is determined by the engine speed. If the engine speed decreases, the maximum flow rate of both the first pump 23 and the second pump 26 will decrease. Therefore, the first pump 23 and the second pump 26 need to output at a high flow rate (which can be understood as more than 80% of the maximum flow rate).

[0038] Specifically, the excavator typically uses power control for the main pumps (first pump 23 and second pump 26), i.e., power = pressure × flow rate. Pressure can be easily identified using a sensor. Flow rate, however, requires an additional flow sensor, which is complex and costly to install. Therefore, when the power is known, the controller converts the pressure into flow rate. For example, if the customer sets the boom lifting height to be higher, the controller will provide a larger flow rate to the main pump (second pump 26) controlling the boom lifting, resulting in a faster boom lifting speed. Conversely, if the customer sets the boom lifting height to be lower, the controller will provide a smaller flow rate to the main pump (second pump 26) controlling the boom lifting, resulting in a slower boom lifting speed. The control principle for increasing and decreasing the swing distance is similar and will not be elaborated upon here.

[0039] Specifically, the oil outlets of the first pump 23 and the second pump 26 are respectively equipped with a first pressure sensor 22 and a second pressure sensor 25 for identifying pressure. 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, during the rotary start-up phase, the rotary pressure is high, and the flow of the first pump controlling the rotary operation is increased accordingly.

[0040] Therefore, in actual operation, the flow patterns of the first pump 23 and the second pump 26 are first adaptively adjusted according to the engine speed. Simultaneously, during the combined action of slewing and boom raising, if the slewing range is smaller (larger) than the preset control strategy's slewing range, the slewing speed can be reduced (increased) by decreasing (increasing) the flow rate of the first pump 23 to achieve adaptive adjustment. If the boom height is smaller (larger) than the preset control strategy's height, the boom speed can be reduced (increased) by decreasing (increasing) the flow rate of the second pump 26 to achieve adaptive adjustment. Through this control strategy, both the slewing range and boom height can be adjusted according to actual needs, with the control objective being that the boom reaches the required height simultaneously with the slewing. This embodiment, based on the auxiliary operation system, can achieve flexible adaptation of the combined slewing and boom raising actions through the flow control of the first pump 23 and the second pump 26, thus meeting the operator's expectations for the coordination of the combined slewing and boom movements.

[0041] Returning to the valve core position adjustment of the first boom valve core 12, when the first boom valve core 12 is in the lowered working position: the hydraulic oil output by the second pump 26 passes through the first boom valve core 12 and reaches the boom cylinder 8. 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. Excess hydraulic oil flows back to the hydraulic oil tank after passing through the first boom valve core 12, thus causing energy waste. Based on this problem, when the first boom valve core 12 is in the lowered working position, this embodiment introduces a boom potential energy unloading valve 10, a boom potential energy regeneration valve 11, and a boom potential energy regeneration cut-off valve 19 to form a boom potential energy cross-loop regeneration oil circuit, a boom potential energy regeneration cut-off oil circuit, and a boom potential energy unloading oil circuit.

[0042] The boom potential energy cross-loop 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 circuit, the boom potential energy regeneration valve 11, the slewing valve core 9, the slewing motor 7, and the slewing valve core 9 in sequence before flowing back to the oil tank, thereby using the regeneration flow to drive the slewing motor 7 to move.

[0043] The boom potential energy regeneration cut-off oil circuit is specifically described as follows: the hydraulic oil flowing out of the rodless chamber of the boom cylinder 8 flows back to the oil tank after passing through the third oil circuit, the third branch circuit, the boom potential energy regeneration valve 11, and the boom potential energy regeneration cut-off valve 19 in sequence, thereby cutting off the oil circuit between the regeneration flow and the rotary valve core 9.

[0044] The boom potential energy unloading oil circuit is specifically as follows: the hydraulic oil flowing out of the rodless chamber of the boom cylinder 8 flows back to the oil tank after passing through the third oil circuit, the second branch circuit, and the boom potential energy unloading valve 10 in sequence.

[0045] Specifically, in this embodiment, through the addition of 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 shut-off valve 19, the regeneration flow generated by the boom potential energy can be utilized by controlling the opening of the boom potential energy regeneration valve 11. Furthermore, the recovered regeneration flow can be used in conjunction with the first pump 23 to control the slewing speed for adaptive adjustment. By controlling the opening of the boom potential energy regeneration shut-off valve 19, the flow rate used to drive the slewing motor 7 within the regeneration flow can be further controlled. By controlling the opening of the boom potential energy unloading valve 10, the back pressure during boom descent can be adjusted to adjust the boom descent speed, thereby coordinating with the second pump 26 to control the boom speed for adaptive adjustment.

[0046] The explanation is based on the combined motion of slewing and boom descent. If the slewing range decreases (increases) compared to the preset control strategy, the combined flow rate of the first pump 23 and the regenerative flow rate to the slewing motor 7 (controlled by the boom potential energy regeneration valve 11 and the boom potential energy regeneration shut-off valve 19) is adaptively reduced (increased) to meet the operator's slewing requirements. If the boom height decreases (increases) compared to the preset control strategy, the boom speed can still be adjusted by reducing (increasing) the flow rate of the second pump 26, or by reducing (increasing) the opening of the boom potential energy unloading valve 10 to increase (decrease) the back pressure during boom descent, thereby achieving adaptive adjustment of the boom speed.

[0047] In summary, the auxiliary operation system provided in this embodiment can adaptively adjust the combined motion of slewing and boom in multiple ways by controlling the flow rate of the first pump 23, the flow rate of the second pump 26, the opening degree of the boom potential energy unloading valve 10, the opening degree of the boom potential energy regeneration valve 11, and the opening degree of the boom potential energy regeneration cut-off valve 19, thereby meeting the driver's needs for the coordination or flexibility of the combined motion.

[0048] In one specific embodiment, both the first oil circuit and the first branch are equipped with check valves to form one-way flow, so as to prevent hydraulic oil backflow.

[0049] In another specific embodiment, the auxiliary operating system further includes a third pump 27, a first control valve 17, a first directional valve 18, and a second control valve 15; the outlet of the third pump 27 is connected to the inlet of the first control valve 17, the first port of the first control valve 17 is connected to the inlet of the second control valve 15, and the 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 inlet and outlet of the second control valve 15 are connected; when the second control valve 15 is in the right position, the inlet and outlet of the second control valve 15 are closed. The second oil port of the first control valve 17 is connected to the control end of the first directional valve 18; the oil inlet of the first control valve 17 can communicate with either the first oil port or the second oil port; the oil inlet and oil outlet of the first directional valve 18 are respectively connected to the oil outlet of the second pump 26 and the oil tank; the first directional valve 18 includes a left position and a right position; the right end of the first directional valve 18 serves as the control end; when the first directional valve 18 is in the left position, the oil inlet and oil outlet of the first directional valve 18 are disconnected, and when the first directional valve 18 is in the right position, the oil inlet and oil outlet of the first directional valve 18 are connected.

[0050] 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 degree of the second boom valve core 20, boom potential energy unloading valve 10, boom potential energy regeneration valve 11 and boom potential energy regeneration shut-off valve 19.

[0051] In addition, when the second pump 26 is not working, the first reversing valve 18 can switch to the right position, so that the oil outlet of the second pump 26 is directly connected to the oil tank, thereby reducing the power of the second pump 26 and achieving energy saving.

[0052] In another specific embodiment, the auxiliary operating system further includes a second directional valve 21. The oil inlet of the second directional valve 21 is connected to the oil outlet of the first pump 23, and the oil outlet of the second directional valve 21 is connected to the oil tank. The second directional valve 21 includes a left position and a right position. When the second directional valve 21 is in the left position, the oil inlet and the oil outlet of the second directional valve 21 are connected. When the second directional valve 21 is in the right position, the oil inlet and the oil outlet of the second directional valve 21 are closed. A ninth solenoid valve 28 is connected to the left end of the second directional valve 21.

[0053] When the first pump 23 is not working, the second reversing valve 21 can switch to the left position, so that the oil outlet of the first pump 23 is directly connected to the oil tank to reduce the power of the first pump 23 and achieve energy saving.

[0054] In one specific embodiment, the control terminals 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 shut-off valve 19 are respectively connected to a first solenoid valve 1, a second solenoid valve 2, a third solenoid valve 3, and a fourth solenoid valve 4; the left and right ends of the rotary valve core 9 are respectively connected to a fifth solenoid valve 5 and a 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 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, the fourth solenoid valve 4, the fifth solenoid valve 5, the sixth solenoid valve 6, the seventh solenoid valve 13, and the eighth solenoid valve 14 are all connected to the control oil circuit. The third pump 27 can provide hydraulic oil to the control oil circuit, so that the first solenoid valve 1, the second solenoid valve 2, the third solenoid valve 3, the fourth solenoid valve 4, the fifth solenoid valve 5, 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 realize the switching or opening control.

[0055] In addition, the oil outlet of the third pump 27 is also connected to a 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

[0056] This embodiment provides an excavator, which includes the hydraulic excavator auxiliary operation system described in Embodiment 1.

[0057] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A hydraulic excavator auxiliary operation system, characterized in that, include: The first pump (23) has its outlet connected to the inlet of the rotary valve core (9) via the first oil circuit; The second pump (26) has its outlet connected to the 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); the return oil port of the first boom valve core (12) is connected to the oil tank. The first oil line is connected to the first branch line, which is connected to the oil inlet of the second boom valve core (20). The oil outlet of the second boom valve core (20) is connected to the oil line between the second working oil port of the first boom valve core (12) and the rodless chamber of the boom cylinder (8) through the third oil line. The third oil line is connected to a second branch, which is connected to the oil inlet of the boom potential energy unloading valve (10), and the oil return port connected to the boom potential energy unloading valve (10) is connected to the oil tank. The third oil line is connected to a third branch, 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 line 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 shut-off valve (19), and the oil outlet of the boom potential energy regeneration shut-off valve (19) is connected to the oil tank. The control terminals of the second boom valve core (20), boom potential energy unloading valve (10), boom potential energy regeneration valve (11), and boom potential energy regeneration shut-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. When the sixth solenoid valve (6) is energized, the rotary valve core (9) is in the left position. The first boom valve core (12) 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 left and right ends 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.

2. The hydraulic excavator auxiliary operation system according to claim 1, characterized in that, The first boom valve core (12) includes an upward working position and a downward working position; When the first boom valve core (12) is in the rising working position, the oil inlet of the first boom valve core (12) is connected to the second working oil port, and the first working oil port of the first boom valve core (12) is connected to the return oil port. When the first boom valve core (12) is in the lowering working position, the oil inlet of the first boom valve core (12) is connected to the first working oil port, and the second working oil port of the first boom valve core (12) is connected to the return oil port.

3. The hydraulic excavator auxiliary operation system according to claim 2, characterized in that, When the first boom valve core (12) is in the rising 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 falling working position, the hydraulic oil exiting from the rodless chamber of the boom cylinder (8) can flow to the second branch or the third branch through the third oil circuit.

4. The hydraulic excavator auxiliary operation system according to claim 1, characterized in that, Both the first oil circuit and the first branch circuit are equipped with check valves to form unidirectional flow.

5. The hydraulic excavator auxiliary operation system according to claim 1, characterized in that, It also includes a third pump (27), a first control valve (17), a first directional 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.

6. The hydraulic excavator auxiliary operation system according to claim 5, characterized in that, When the second control valve (15) is in the left position, the oil inlet and 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 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 directional valve (18). The oil inlet of the first control valve (17) can be connected to the first oil port or the second oil port.

7. The hydraulic excavator auxiliary operation system according to claim 6, characterized in that, The inlet and outlet of the first directional valve (18) are respectively connected to the outlet of the second pump (26) and the oil tank; the first directional valve (18) includes a left position and a right position; the right end of the first directional valve (18) serves as the control end; when the first directional valve (18) is in the left position, the inlet and outlet of the first directional valve (18) are disconnected, and when the first directional valve (18) is in the right position, the inlet and outlet of the first directional valve (18) are connected.

8. The hydraulic excavator auxiliary operation system according to claim 5, characterized in that, The oil outlet of the third pump (27) is also connected to the 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).

9. The hydraulic excavator auxiliary operation system according to claim 5, characterized in that, It also includes a second directional valve (21), the oil inlet of the second directional valve (21) is connected to the oil outlet of the first pump (23), the oil outlet of the second directional valve (21) is connected to the oil tank, the second directional valve (21) includes a left position and a right position; when the second directional valve (21) is in the left position, the oil inlet and the oil outlet of the second directional valve (21) are connected, and when the second directional valve (21) is in the right position, the oil inlet and the oil outlet of the second directional valve (21) are cut off; the left end of the second directional valve (21) is connected to a ninth solenoid valve (28).

10. The hydraulic excavator auxiliary operation system according to claim 1, characterized in that, The first pump (23) and the second pump (26) are respectively equipped with a first pressure sensor (22) and a second pressure sensor (25) at their oil outlets.

11. An excavator, characterized in that, Includes the hydraulic excavator auxiliary operation system as described in any one of claims 1-10.

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