Rotary hydraulic systems and construction machinery

Abstract

The present invention belongs to the technical field of engineering machinery, and specifically relates to a rotary hydraulic system and engineering machinery. The rotary hydraulic system includes: a torque output device for driving a load to rotate; a rotary control valve group connected to the torque output device via an oil circuit; and a priority valve connected to the rotary control valve group via an oil circuit. The priority valve can adjust the oil supply according to the flow demand of the torque output device. Through the technical solution of the present invention, oil can be supplied to the torque output device on a priority basis, and the oil supply can be adjusted according to the demand of the torque output device, thereby improving the accuracy of the oil supply and enabling the torque output device to output torque smoothly during starting and stopping, which is beneficial to improving rotational stability, reducing system heat generation, and reducing energy loss.

Description

Technical Field

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

[0002] Wheeled cranes and other construction machinery typically use a hydraulic system consisting of a fixed displacement pump, a fixed displacement hydraulic motor, a slew control valve group, and an auxiliary control valve group to drive the slewing mechanism. However, existing hydraulic systems suffer from low efficiency and poor oil supply accuracy, leading to severe system heating and energy loss. Furthermore, system pressure overshoot occurs during starting and stopping, significantly impacting the system's oil circuits and causing severe vibration in the slewing mechanism, impacting the normal operation of the construction machinery. Summary of the Invention

[0003] In view of this, in order to solve the problems in the prior art such as poor oil supply accuracy, large energy loss, and severe shaking of the rotary mechanism caused by large impact pressure in the system oil circuit during starting and stopping, the present invention provides a rotary hydraulic system and an engineering machinery.

[0004] The present invention provides a rotary hydraulic system, comprising: a torque output device for driving a load to rotate; a rotary control valve group connected to the torque output device through an oil circuit; and a priority valve connected to the rotary control valve group through an oil circuit, wherein the priority valve can adjust the oil supply according to the flow demand of the torque output device.

[0005] In one possible implementation, the torque output device includes a hydraulic motor; the rotary control valve group is provided with a first oil inlet, a first oil return port, a first connecting port and a second connecting port, the first connecting port is connected to one oil port of the hydraulic motor, and the second connecting port is connected to another oil port of the hydraulic motor; the priority valve is connected to the first oil inlet through an oil supply circuit to supply oil to the rotary control valve group; the priority valve is connected to the oil circuit connected to the first oil return port in the rotary control valve group through the regulating oil circuit.

[0006] In a possible implementation, the priority valve is provided with a second oil inlet, a second oil return port, a third connecting port, a fourth connecting port, a fifth connecting port and a rotary valve; the second oil inlet is used to connect the oil supply device to inlet oil, the third connecting port is communicated with the oil supply oil circuit, the fourth connecting port is used to connect the external hydraulic system, the fifth connecting port is communicated with the regulating oil circuit, the fifth connecting port is connected to the second oil return port through an oil circuit, and a first throttle valve and a first pressure relief valve are provided in the oil circuit connecting the fifth connecting port and the second oil return port, the rotary valve is connected to the oil circuit connecting the fifth connecting port and the first throttle valve through the first throttle hole, and the rotary valve is connected to the oil circuit connecting the rotary valve and the third connecting port through the second throttle hole; wherein, the return The rotary valve is provided with a first position near the first throttle hole, and the rotary valve is provided with a second position near the second throttle hole. The rotary valve can move between the first position and the second position to adjust the flow in the oil supply circuit; wherein, when the rotary valve is in the first position, the second oil inlet is connected to the third connecting port, and the fourth connecting port is closed; when the rotary valve moves from the first position to the second position, the second oil inlet is connected to both the third connecting port and the fourth connecting port, and the oil supply of the third connecting port gradually decreases, and the oil supply of the fourth connecting port gradually increases; when the rotary valve is in the second position, the second oil inlet is connected to both the third connecting port and the fourth connecting port, and the second oil inlet supplies oil to the fourth connecting port preferentially.

[0007] In one possible implementation, the priority valve also includes: a third one-way valve, which is arranged in the oil circuit connecting the fourth connecting port and the rotary valve, and the third one-way valve is unidirectionally conducted from the rotary valve to the fourth connecting port; a second pressure relief valve, which is connected to both ends of the third one-way valve through the oil circuit, and the oil outlet of the second pressure relief valve is connected to the second oil return port.

[0008] In one possible implementation, the slewing control valve group includes: a control valve, which is a three-position reversing valve for controlling the flow direction of the hydraulic oil flowing through the hydraulic motor; a shuttle valve, wherein one oil inlet of the shuttle valve is connected to the oil circuit connected to the first connecting port, and the other oil inlet of the shuttle valve is connected to the oil circuit connected to the second connecting port; a first bypass oil circuit, one end of which is connected to the oil outlet of the shuttle valve, and the other end is connected to the control valve, and the first bypass oil circuit is connected to a second throttle valve and a high-pressure unloading valve; an oil supply circuit, one end of which is connected to the oil circuit connected to the first connecting port, and the other end is connected to the oil circuit connected to the second connecting port, and the oil supply circuit is connected to two first one-way valves arranged in opposite directions; wherein, when the control valve is in the middle position, the first bypass oil circuit is connected to the position between the two first one-way valves in the oil supply circuit; when the control valve is in the left position or the right position, the first bypass oil circuit is connected to the oil circuit connected to the first oil return port.

[0009] In one possible implementation, the control valve is provided with a first valve port, a second valve port, a third valve port, a fourth valve port, a fifth valve port and a sixth valve port, the first valve port is connected to the first oil inlet, the second valve port is connected to the first bypass oil circuit, the third valve port is connected to the first oil return port, the fourth valve port is connected to the first connecting port through the oil circuit, the fifth valve port is connected to the oil replenishment circuit between the two first one-way valves through the oil circuit, and the sixth valve port is connected to the second connecting port through the oil circuit; wherein, the control valve is connected to the control oil circuit for connecting the pilot hydraulic system to control the reversing of the control valve; when the control valve is in the middle position, the second valve port is connected to the fifth valve port; when the control valve is in the left position, the first valve port is unidirectionally connected to the fourth valve port, and the second valve port and the sixth valve port are both throttled and connected to the third valve port; when the control valve is in the right position, the first valve port is unidirectionally connected to the sixth valve port, and the second valve port and the fourth valve port are both throttled and connected to the third valve port.

[0010] In a possible implementation, the rotary control valve group further includes: a second one-way valve, which is provided at the first oil return port, and the second one-way valve is unidirectionally conducted from the control valve to the first oil return port.

[0011] In one possible implementation, the rotary control valve group also includes: a buffer oil circuit, one end of which is connected to the oil circuit connected to the first connection port, and the other end is connected to the oil circuit connected to the second connection port, and two buffer valves arranged opposite to each other are connected to the buffer oil circuit.

[0012] In a feasible implementation, the rotary control valve group also includes a second bypass oil circuit, one end of the second bypass oil circuit is connected to the oil outlet of the shuttle valve, and the other end of the second bypass oil circuit is connected to the first bypass oil circuit between the high-pressure unloading valve and the control valve, and a first reversing valve is provided in the second bypass oil circuit for controlling the conduction or disconnection of the second bypass oil circuit; the priority valve also includes a second reversing valve, the second reversing valve is provided at the fifth connecting port, and the second reversing valve is connected to the second throttle hole through the third bypass oil circuit; the second reversing valve is used to control the communication between the fifth connecting port and the first throttle hole; or the second reversing valve is used to control the communication between the fifth connecting port and the third bypass oil circuit.

[0013] The present invention also provides an engineering machine, comprising: a slewing mechanism; and the slewing hydraulic system of any one of the above items, wherein a torque output device of the slewing hydraulic system is transmission-connected to the slewing mechanism to drive the slewing mechanism to rotate.

[0014] The beneficial effects of the above technical solution of the present invention are embodied in:

[0015] Through the combination of the swing control valve group and the priority valve, oil can be supplied to the torque output device in priority, and the oil supply amount can be adjusted according to the needs of the torque output device, thereby improving the accuracy of oil supply, thereby reducing the impact pressure in the oil circuit during starting and stopping, and enabling the torque output device to output torque smoothly, thereby alleviating the jitter of the swing mechanism.

[0016] In addition, compared with the solution of using a proportional valve to adjust the oil supply in the existing hydraulic system, the oil supply of the rotary hydraulic system of the present invention can always be adapted to the demand of the torque output device, and the accuracy of the oil supply adjustment is higher, which is conducive to reducing system heat and energy loss. While adjusting the oil supply, excess flow can be output to the external hydraulic system, thereby improving the system's working efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a schematic diagram of a rotary hydraulic system provided by one embodiment of the present invention.

[0018] Figure 2 Shown is a schematic diagram of a rotary hydraulic system provided by one embodiment of the present invention.

[0019] Figure 3 Shown is a schematic diagram of a rotary hydraulic system provided by one embodiment of the present invention.

[0020] Figure 4 Shown is a schematic diagram of a control valve of a rotary hydraulic system provided by one embodiment of the present invention.

[0021] Figure 5 Shown is a schematic diagram of a rotary hydraulic system provided by one embodiment of the present invention.

[0022] Figure 6 Shown is a schematic diagram of a rotary hydraulic system provided by one embodiment of the present invention.

[0023] Description of reference numerals:

[0024] 1 Torque output device, 11 Hydraulic motor, 2 Rotary control valve group, 211 First oil inlet, 212 First oil return port, 213 First connection port, 214 Second connection port, 22 Control valve, 221 First valve port, 222 Second valve port, 223 Third valve port, 224 Fourth valve port, 225 Fifth valve port, 226 Sixth valve port, 23 Shuttle valve, 24 First bypass oil circuit, 241 Second throttle valve, 242 High-pressure unloading valve, 25 Oil supply circuit, 251 First check valve, 26 Second bypass oil circuit, 261 First reversing valve , 27 second one-way valve, 28 buffer oil circuit, 281 buffer valve, 29 control oil circuit, 3 priority valve, 311 second oil inlet, 312 second oil return port, 313 third connecting port, 314 fourth connecting port, 315 fifth connecting port, 32 rotary valve, 331 first throttle valve, 332 first pressure relief valve, 333 first throttle hole, 334 second throttle hole, 335 second reversing valve, 336 third one-way valve, 337 second pressure relief valve, 34 third bypass oil circuit, 41 oil supply circuit, 42 regulating oil circuit, 5 rotary mechanism. DETAILED DESCRIPTION

[0025] In the description of the application, the meaning of "multiple" is at least two, for example two, three, etc., unless otherwise clearly and specifically limited. In the embodiments of the present application, all directional indications (such as up, down, left, right, front, back, top, bottom ...) are only used to explain the relative position relationship, motion situation, etc. between each component under a certain specific posture (as shown in the drawings). If this specific posture changes, this directional indication also changes accordingly. In addition, the terms "comprise" and "have" and any deformation thereof are intended to cover non-exclusive inclusion. For example, the process, method, system, product or equipment comprising a series of steps or units is not limited to the steps or units listed, but optionally also includes the steps or units not listed, or optionally also includes other steps or units inherent to these processes, methods, products or equipment.

[0026] In addition, references to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of such phrases in various places in the specification does not necessarily refer to the same embodiment, nor does it necessarily refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0027] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0028] The following embodiments provide a rotary hydraulic system and engineering machinery in the technical solution of the present invention.

[0029] like Figure 1As shown, in one embodiment of the present invention, a rotary hydraulic system is provided, which can be applied to engineering machinery with a rotary mechanism. The rotary hydraulic system includes a torque output device 1, a rotary control valve group 2, and a priority valve 3. The rotary control valve group 2 is connected to the torque output device 1 through an oil circuit, and the priority valve 3 is connected to the rotary control valve group 2 through an oil circuit; the priority valve 3 can be connected to an oil supply device and an oil return device. When the rotary control valve group 2 is in a conducting state, the priority valve 3 can supply oil to the torque output device 1 through the rotary control valve group 2, so that the torque output device 1 works and drives the load (such as the rotary mechanism 5 of the engineering machinery) to rotate. The priority valve 3 can supply the hydraulic oil supplied by the oil supply device to the torque output device 1 in priority. According to the different flow rates required by the torque output device 1, the priority valve 3 can perform corresponding flow adjustment operations to ensure that the oil supply is always adapted to the demand of the torque output device 1, so as to alleviate the heating phenomenon caused by excessive oil supply to the torque output device 1, thereby reducing the impact pressure in the oil circuit during starting and stopping, so that the torque output device 1 can operate smoothly; when the torque output device 1 drives the slewing mechanism 5 of the engineering machinery, it can effectively alleviate the shaking phenomenon of the slewing mechanism 5 during starting and stopping, which is beneficial to improving the operating stability of the slewing mechanism 5.

[0030] In addition, the priority valve 3 can also be connected to an external hydraulic system to divert excess hydraulic oil to the external hydraulic system when supplying oil to the torque output device 1 to drive the external hydraulic system to work, which is beneficial to improving the use efficiency of hydraulic oil and reducing energy consumption loss.

[0031] The rotary hydraulic system in this embodiment, through the combination of the rotary control valve group 2 and the priority valve 3, can effectively improve the oil supply accuracy, reduce the impact pressure in the oil circuit when the load starts and stops, enable the torque output device 1 to output torque smoothly, and when the torque output device 1 drives the rotary mechanism 5, it can effectively alleviate the shaking phenomenon of the rotary mechanism 5.

[0032] Compared with the solution of using proportional valves to adjust the oil supply in existing hydraulic systems, the oil supply of the rotary hydraulic system of the present invention can always be adapted to the demand of the torque output device 1, and the accuracy of the oil supply adjustment is higher, which is conducive to reducing system heat and energy loss. When the priority valve 3 is connected to the external hydraulic system, the excess flow can be output to the external hydraulic system during the process of adjusting the oil supply, thereby improving the system working efficiency.

[0033] In some embodiments of the present invention, Figure 1 and Figure 2As shown, the torque output device 1 specifically includes a hydraulic motor 11, which drives the hydraulic motor 11 to output torque through hydraulic oil, thereby driving the load to rotate. The rotary control valve group 2 is provided with a first oil inlet 211, a first oil return port 212, a first connecting port 213 and a second connecting port 214, and the first connecting port 213 and the second connecting port 214 are respectively connected to the two oil ports of the hydraulic motor 11. Among them, the first connecting port 213 corresponds to Figure 2 The second connection port 214 corresponds to the A port in Figure 2 Port B in the hydraulic motor 11 is connected to port A through an oil circuit, and port B is connected to another oil circuit of the hydraulic motor 11 through an oil circuit. Hydraulic oil can flow in from port A and out from port B, or flow in from port B and out from port A, so as to change the rotation direction of the hydraulic motor 11. An oil supply circuit 41 and an adjusting circuit 42 are provided between the priority valve 3 and the rotary control valve group 2. The priority valve 3 is connected to the first oil inlet 211 of the rotary control valve group 2 through the oil supply circuit 41, and is connected to the oil circuit connected to the first oil return port 212 in the rotary control valve group 2 through the adjusting circuit 42. The priority valve 3 can supply oil to the rotary control valve group 2 through the oil supply circuit 41, and can use the adjusting circuit 42 to introduce a part of the return oil of the rotary control valve group 2 to adjust the oil supply of the priority valve 3 so that the oil supply of the priority valve 3 is adapted to the demand of the hydraulic motor 11.

[0034] It can be understood that devices such as proportional valves commonly used in existing hydraulic systems require manual operation to adjust the oil supply, and the accuracy of the oil supply is difficult to ensure. The rotary hydraulic system in this embodiment can achieve system adaptive adjustment, which is more convenient to adjust and has higher oil supply accuracy.

[0035] In some embodiments of the present invention, Figure 2 As shown, the priority valve 3 is provided with a second oil inlet 311, a second oil return port 312, a third connecting port 313, a fourth connecting port 314 and a fifth connecting port 315, wherein the third connecting port 313 corresponds to Figure 2 The CF port in the fourth connection port 314 corresponds to Figure 2 The fifth connection port 315 corresponds to the EF port in Figure 2 The second oil inlet 311 is used to connect to the oil supply device for oil intake. The CF port is connected to the oil supply oil circuit 41 to supply oil to the swing control valve group 2. The second oil return port 312 is used to connect to the oil return device. The EF port is used to connect to the external hydraulic system to divert excess hydraulic oil to the external hydraulic system. The LS port is connected to the regulating oil circuit 42.

[0036] A rotary valve 32 is provided in the priority valve 3; the LS port is connected to the second oil return port 312 through an oil circuit, and a first throttle valve 331 and a first pressure relief valve 332 are provided in the oil circuit between the LS port and the second oil return port 312; the rotary valve 32 is connected to a first throttle hole 333 and a second throttle hole 334, and the first throttle hole 333 is connected to the oil circuit between the LS port and the first throttle valve 331. Through the throttling effect of the first throttle valve 331, a part of the hydraulic oil in the oil circuit flows to the rotary valve 32 through the first throttle hole 333, so as to transmit a pressure signal to the rotary valve 32; when the pressure in the oil circuit is too high, the hydraulic oil flows to the second oil return port 312 through the first pressure relief valve 332, thereby realizing the recovery of the hydraulic oil and the pressure relief of the oil circuit. The second throttle hole 334 is connected to the oil circuit between the CF port and the rotary valve 32 . A portion of the hydraulic oil flowing to the CF port can flow to the rotary valve 32 through the second throttle hole 334 to transmit a pressure signal to the rotary valve 32 .

[0037] The rotary valve 32 has two operating positions: a first position near the first orifice 333 and a second position near the second orifice 334. The rotary valve 32 is movable between the first and second positions. The initial position of the rotary valve 32 is the first position, with the second oil inlet 311 connected to the CF port and the oil circuit connected to the EF port disconnected. At this point, if the rotary control valve assembly 2 is disconnected, the CF port is closed and no oil is supplied. The pressure in the first orifice 333 is zero, while the pressure in the second orifice 334 is greater than that in the first orifice 333. Under the action of this pressure, the rotary valve 32 moves toward the second position. During this movement, the oil circuit connected to the EF port becomes open, and the oil supply to the EF port gradually increases, while the oil supply to the CF port gradually decreases, allowing the hydraulic oil to flow preferentially to the external hydraulic system. When the rotary valve 32 is in the first position, if the rotary control valve group 2 is turned on, the priority valve 3 supplies oil to the hydraulic motor 11 through the oil supply line 41 and the rotary control valve group 2. A portion of the hydraulic oil flowing to the first return oil port 212 in the rotary control valve group 2 flows to the first throttle hole 333 through the regulating oil line 42. If the pressure of the second throttle hole 334 is greater than the pressure of the first throttle hole 333, it indicates that the supply oil pressure is greater than the return oil pressure. At this time, the rotary valve 32 moves a certain distance from the first position to the second position under the action of pressure, so that the oil circuit connected to the EF port is turned on, so that a portion of the hydraulic oil flowing into the rotary valve 32 through the second oil inlet 311 is diverted to the external hydraulic system through the EF port, and the movement distance of the rotary valve 32 corresponds to the pressure difference at both ends, thereby adaptively adjusting the oil supply according to the demand of the hydraulic motor 11.

[0038] It should be noted that the external hydraulic system may also include one or more hydraulic motors 11 , and the rotary hydraulic system in this embodiment can drive multiple hydraulic motors 11 to work simultaneously, thereby further improving work efficiency.

[0039] In some embodiments of the present invention, Figure 2 As shown, the swing control valve group 2 includes a control valve 22, a shuttle valve 23, a first bypass oil circuit 24, and an oil replenishment circuit 25. The control valve 22 is specifically a three-position reversing valve. By reversing the control valve 22, the swing control valve group 2 is turned on or off, and the flow direction of the hydraulic oil is changed to adjust the rotation direction of the hydraulic motor 11. The shuttle valve 23 is arranged between the two oil circuits connecting ports A and B. One oil inlet of the shuttle valve 23 is connected to the oil circuit connecting port A, and the other oil inlet of the shuttle valve 23 is connected to the oil circuit connecting port B. The oil outlet of the shuttle valve 23 is connected to the first bypass oil circuit 24, and the other end of the first bypass oil circuit 24 is connected to the control valve 22. The first bypass oil circuit 24 is connected to a second throttle valve 241 and a high-pressure unloading valve 242. Similar to shuttle valve 23, one end of the oil supply circuit 25 connects to the oil circuit connected to port A, and the other end connects to the oil circuit connected to port B. Two first check valves 251, arranged opposite each other, are connected to the oil supply circuit 25. Both first check valves 251 are unidirectional. These two first check valves 251 are arranged opposite each other. Specifically, the left first check valve 251 can conduct oil from right to left, while the right first check valve 251 can conduct oil from left to right. Alternatively, hydraulic oil entering the oil supply circuit 25 between the two first check valves 251 can be split into two paths, each passing through the corresponding first check valve 251 to connect to the oil supply circuit 25.

[0040] When the control valve 22 is in the left or right position, the control valve 22 is in a conducting state, and the first bypass oil passage 24 is connected to the oil passage connecting to the first oil return port 212. At this time, the priority valve 3 supplies oil to the hydraulic motor 11 through the swing control valve assembly 2. The hydraulic oil flows through the hydraulic motor 11 and then flows through the control valve 22 to the first oil return port 212. During the hydraulic oil return process, it is throttled in the control valve 22. Part of the throttled hydraulic oil flows through the first oil return port 212 to the oil return device, and part flows to the priority valve 3 through the regulating oil passage 42. When the hydraulic oil flow to the hydraulic motor 11 is large, some of the hydraulic oil can flow through the shuttle valve 23 into the first bypass oil passage 24. After being throttled by the second throttle valve 241, the high-pressure unloading valve 242 is opened, and the hydraulic oil is throttled by the control valve 22 before flowing to the first oil return port 212. The hydraulic oil flow direction is opposite when the control valve 22 is in the left position and when it is in the right position, so that the rotation direction of the hydraulic motor 11 can be controlled by reversing the control valve 22. When the control valve 22 is switched to the middle position, the first bypass oil circuit 24 is connected to the position between the two first one-way valves 251 in the oil supply circuit 25. At this time, the control valve 22 is in the disconnected state. Since the hydraulic motor 11 will continue to rotate for a period of time under the action of inertia, the flow rate of the hydraulic oil between port A and port B will be different, and the flow rate on the return oil side is greater than the flow rate on the supply side. The shuttle valve 23 can allow a part of the hydraulic oil on the return oil side to flow into the first bypass oil circuit 24. After throttling by the second throttle valve 241, the high-pressure unloading valve 242 is opened, and the hydraulic oil in the first bypass oil circuit 24 flows into the supply side through the oil supply circuit, so that the flow rate on the supply side and the return side of the hydraulic motor 11 remains relatively balanced, so as to prevent damage to the hydraulic motor 11 and related oil circuits.

[0041] In some embodiments of the present invention, Figure 3 and Figure 4 As shown, the control valve 22 is specifically a three-position, six-way reversing valve having six valve ports: a first valve port 221, a second valve port 222, a third valve port 223, a fourth valve port 224, a fifth valve port 225, and a sixth valve port 226. The first valve port 221 is connected to the first oil inlet 211, the second valve port 222 is connected to the first bypass oil passage 24, the third valve port 223 is connected to the first oil return port 212, the fourth valve port 224 is connected to port A via an oil passage, the fifth valve port 225 is connected to the oil replenishment passage 25 between the two first check valves 251 via an oil passage, and the sixth valve port 226 is connected to port B via an oil passage.

[0042] The control valve 22 is connected to the control oil circuit 29. The swing control valve assembly 2 is provided with corresponding ports C and D, which are connected to the two ends of the control oil circuit 29, respectively, for connecting to the pilot hydraulic system to drive the control valve 22 to change direction. The connection relationship between the six valve ports of the control valve 22 is different when the control valve 22 is in the left, center, and right positions. Specifically, when the control valve 22 is in the center position, the second valve port 222 is connected to the fifth valve port 225, and the other four valve ports are closed. At this time, the swing control valve assembly 2 is in a disconnected state, and only the first bypass oil circuit 24 is connected to the oil replenishment circuit 25, thereby balancing the flow of hydraulic oil on both sides of the hydraulic motor 11. When the control valve 22 is in the left position, the first valve port 221 is unidirectionally connected to the fourth valve port 224, the second valve port 222 and the sixth valve port 226 are both throttled and connected to the third valve port 223, and the fifth valve port 225 is closed. At this time, the oil supply line 41 normally supplies oil to the swing control valve group 2. The hydraulic oil flows through the first valve port 221 and the fourth valve port 224 of the control valve 22 to port A, and then flows into the hydraulic motor 11, driving the hydraulic motor 11 to output torque. The hydraulic oil then flows through port B to the sixth valve port 226 of the control valve 22. At this time, most of the hydraulic oil flows to the first oil return port 212 after being throttled, and a small amount of hydraulic oil flows to the LS port of the priority valve 3 through the regulating oil line 42 after being throttled, thereby transmitting pressure information to the swing valve 32. When the high-pressure unloading valve 242 is open, the hydraulic oil in the first bypass oil line 24 can also flow into the control valve 22 and, after being throttled, flow to the first oil return port 212. When the control valve 22 is in the right position, the first valve port 221 is unidirectionally connected to the sixth valve port 226 , the second valve port 222 and the fourth valve port 224 are both throttled and connected to the third valve port 223 , and the fifth valve port 225 is closed. At this time, the oil supply line 41 normally supplies oil to the swing control valve assembly 2 . Hydraulic oil flows through the first valve port 221 and the sixth valve port 226 of the control valve 22 to port B, and then into the hydraulic motor 11 , driving the hydraulic motor 11 to output torque. The hydraulic oil then flows through port A to the fourth valve port 224 of the control valve 22 . At this time, most of the hydraulic oil flows to the first oil return port 212 after being throttled. A small amount of hydraulic oil flows through the regulating oil line 42 after being throttled to the LS port of the priority valve 3 to transmit pressure information to the swing valve 32 . When the high-pressure unloading valve 242 is open, the hydraulic oil in the first bypass oil line 24 can also flow into the control valve 22 and, after being throttled, flow to the first oil return port 212 .

[0043] Furthermore, a second one-way valve 27 is provided at the first oil return port 212 of the rotary control valve group 2. The second one-way valve 27 is unidirectionally conducted from the control valve 22 to the first oil return port 212 to prevent the hydraulic oil in the oil return device from flowing into the rotary control valve group 2 after the first oil return port 212 is connected to the oil return device.

[0044] In some embodiments of the present invention, Figure 4 and Figure 5As shown, a buffer oil circuit 28 is also provided in the rotary control valve group 2. Specifically, the buffer oil circuit 28 is arranged between the oil circuit connected to port A and the oil circuit connected to port B. One end of the buffer oil circuit 28 is connected to the oil circuit connected to port A, and the other end of the buffer oil circuit 28 is connected to the oil circuit connected to port B. Two buffer valves 281 are connected to the buffer oil circuit 28, and the two buffer valves 281 are arranged opposite each other. Each buffer valve 281 has a unidirectional conduction function. When the pressure at either end of the buffer oil circuit 28 is higher, the buffer valve 281 on the side with higher pressure is turned on, and the hydraulic oil flows into the buffer oil circuit 28 through the buffer valve 281, and then flows to the other end of the buffer oil circuit 28 through the other buffer valve 281, thereby reducing the pressure difference between the supply side and the return side of the hydraulic motor 11, thereby balancing the pressure on both sides of the hydraulic motor 11.

[0045] For example, when the control valve 22 switches from the left or right position to the neutral position, the oil supply to the hydraulic motor 11 stops. However, the hydraulic motor 11 continues to rotate for a period of time due to inertia, resulting in different pressures on both sides of the hydraulic motor 11, creating a pressure differential. The buffer oil circuit 28 can effectively balance the pressures on both sides of the hydraulic motor 11.

[0046] In some embodiments of the present invention, Figure 5 As shown, the priority valve 3 is also provided with a third one-way valve 336 and a second pressure relief valve 337. Specifically, the third one-way valve 336 is connected to the oil circuit between the rotary valve 32 and the EF port, and the oil outlet of the third one-way valve 336 is connected to the EF port, so that the oil circuit is unidirectionally conducted from the rotary valve 32 to the EF port, so as to prevent the hydraulic oil in the external hydraulic system from flowing into the priority valve 3 when the EF port is connected to the external hydraulic system. The second pressure relief valve 337 is connected to the oil inlet and oil outlet of the third one-way valve 336 through the oil circuit, and the oil outlet of the second pressure relief valve 337 is connected to the second oil return port 312, so that when the pressure of the hydraulic oil flowing to the EF port is too large, the excess hydraulic oil is led to the second oil return port 312 through the second pressure relief valve 337 and discharged into the oil return device to achieve pressure relief. Among them, the second pressure relief valve 337 can be connected to the oil circuit connecting the first pressure relief valve 332 and the second oil return port 312 through the oil circuit, as shown in FIG. Figure 5 In the example in FIG, two second oil return ports 312 may be provided, connected to the first pressure relief valve 332 and the second pressure relief valve 337 respectively.

[0047] In some embodiments of the present invention, Figure 6As shown, the swing control valve assembly 2 also includes a second bypass oil circuit 26. One end of the second bypass oil circuit 26 is connected to the oil outlet of the shuttle valve 23, and the other end of the second bypass oil circuit 26 is connected to the first bypass oil circuit 24 between the high-pressure unloading valve 242 and the control valve 22. A first reversing valve 261 is provided in the second bypass oil circuit 26 to control the flow of the second bypass oil circuit 26. Correspondingly, a second reversing valve 335 is provided at the LS port of the priority valve 3. A third bypass oil circuit 34 is provided between the second reversing valve 335 and the second throttle orifice 334. The second reversing valve 335 can control the flow of the LS port to communicate with the first throttle orifice 333, or to communicate with the second throttle orifice 334 through the third bypass oil circuit 34. The first reversing valve 261 and the second reversing valve 335 may be solenoid reversing valves.

[0048] When the hydraulic motor 11 is operating normally, the first reversing valve 261 is in the open position, and the second reversing valve 335 is switched to connect the LS port to the first orifice 333. When the hydraulic motor 11 switches to the free-swing state, the first reversing valve 261 is switched to the open position, and the second reversing valve 335 is switched to connect the LS port to the third bypass oil passage 34. At this point, the LS port is connected to the second orifice 334 via the third bypass oil passage 34. The pressure at the end of the rotary valve 32 near the first orifice 333 is much lower than the pressure at the end near the second orifice 334. Under the action of pressure, the rotary valve 32 moves to the second position. Hydraulic oil is preferentially supplied to the external hydraulic system through the EF port, and oil supply to the rotary control valve assembly 2 is stopped. The hydraulic motor 11 stops outputting torque and enters the free-swing state, allowing it to freely rotate according to the rotational requirements of the load.

[0049] Further, if Figure 6 As shown, when the hydraulic motor 11 just switches to the free rotation state, due to inertia, the hydraulic motor 11 will continue to rotate for a period of time. At this time, there may be a pressure difference between the two ends of the hydraulic motor 11. The buffer oil circuit 28 can be used to allow part of the hydraulic oil on the higher pressure side to flow into the lower pressure side to balance the pressure on both sides of the hydraulic motor 11 and eliminate the pressure difference, so that the hydraulic motor 11 can achieve free rotation.

[0050] The following is a specific embodiment of the rotary hydraulic system of the present invention:

[0051] like Figure 6 As shown, the rotary hydraulic system includes a torque output device 1 , a rotary control valve group 2 and a priority valve 3 , and can be applied to engineering machinery with a rotary mechanism 5 .

[0052] The torque output device 1 specifically includes a hydraulic motor 11, which is in transmission connection with the rotary mechanism 5 to drive the rotary mechanism 5 to rotate. The rotary control valve group 2 is provided with a first oil inlet 211, a first oil return port 212, a first connecting port 213 and a second connecting port 214, wherein the first connecting port 213 and the second connecting port 214 are respectively connected to the two oil ports of the hydraulic motor 11. The first connecting port corresponds to Figure 6 The second connection port 214 corresponds to the A port in Figure 6 The B port in the oil pump is connected to the oil port of the hydraulic motor 11 through the oil circuit, and the A port is connected to an oil port of the hydraulic motor 11 through the oil circuit, and the B port is connected to the other oil port of the hydraulic motor 11 through the oil circuit.

[0053] The priority valve 3 is provided with a second oil inlet 311, a second oil return port 312, a third connecting port 313, a fourth connecting port 314 and a fifth connecting port 315, wherein the third connecting port 313 corresponds to Figure 6 The CF port in the fourth connection port 314 corresponds to Figure 6 The fifth connection port 315 corresponds to the EF port in Figure 6 The second oil inlet 311 is connected to the oil supply device for oil intake. The CF port is connected to the first oil inlet 211 via the oil supply oil line 41 to supply oil to the swing control valve group 2. The second oil return port 312 is connected to the oil return device. The EF port is used to connect to the external hydraulic system to divert excess hydraulic oil to the external hydraulic system. The LS port is connected to the oil line connected to the first oil return port 212 in the swing control valve group 2 via the regulating oil line 42.

[0054] A rotary valve 32 is provided within the priority valve 3. The LS port is connected to the second oil return port 312 via an oil circuit. The oil circuit between the LS port and the second oil return port 312 is connected to a first throttle valve 331 and a first pressure relief valve 332. The rotary valve 32 is connected to a first throttle hole 333 and a second throttle hole 334. The first throttle hole 333 is connected to the oil circuit between the LS port and the first throttle valve 331. The throttling action of the first throttle valve 331 causes a portion of the hydraulic oil in the oil circuit to flow through the first throttle hole 333 to one end of the rotary valve 32, thereby transmitting a pressure signal to the rotary valve 32. When the pressure in the oil circuit is too high, the first pressure relief valve 332 is opened, allowing the hydraulic oil to flow through the first pressure relief valve 332 to the second oil return port 312, thereby relieving the oil circuit pressure. The second orifice 334 connects to the oil circuit between the CF port and the rotary valve 32. A portion of the hydraulic oil flowing to the CF port can flow through the second orifice 334 to the other end of the rotary valve 32, thereby transmitting a pressure signal to the rotary valve 32. A second reversing valve 335 is also provided at the LS port of the priority valve 3. A third bypass oil circuit 34 is provided between the second reversing valve 335 and the second orifice 334. The second reversing valve 335 can control the communication between the LS port and the first orifice 333, or control the communication between the LS port and the second orifice 334 via the third bypass oil circuit 34.

[0055] The rotary valve 32 has two operating positions: a first position near the first orifice 333 and a second position near the second orifice 334. The rotary valve 32 is movable between the first and second positions. Normally, the second reversing valve 335 is in a state where the LS port is connected to the first orifice 333. The initial position of the rotary valve 32 is the first position, with the second oil inlet 311 connected to the CF port and the oil circuit connected to the EF port disconnected. At this point, if the rotary control valve assembly 2 is disconnected, the CF port is closed and no oil is supplied. The pressure in the first orifice 333 is zero, while the pressure in the second orifice 334 is greater than that in the first orifice 333. When the rotary valve 32 moves toward the second position under pressure, the oil circuit connected to the EF port is open, and the oil supply to the EF port gradually increases, while the oil supply to the CF port gradually decreases, with oil preferentially flowing to the external hydraulic system. When the rotary valve 32 is in the first position, if the rotary control valve group 2 is turned on, the priority valve 3 supplies oil to the hydraulic motor 11 through the oil supply line 41 and the rotary control valve group 2. A portion of the hydraulic oil flowing to the first return oil port 212 in the rotary control valve group 2 flows to the first throttle hole 333 through the regulating oil line 42. If the pressure of the second throttle hole 334 is greater than the pressure of the first throttle hole 333, it indicates that the supply oil pressure is greater than the return oil pressure. At this time, the rotary valve 32 moves a certain distance from the first position to the second position under the action of pressure, so that the oil circuit connected to the EF port is turned on, so that a portion of the hydraulic oil flowing into the rotary valve 32 through the second oil inlet 311 is diverted to the external hydraulic system through the EF port, and the movement distance of the rotary valve 32 corresponds to the pressure difference at both ends, thereby adaptively adjusting the oil supply according to the demand of the hydraulic motor 11.

[0056] The priority valve 3 is also provided with a third one-way valve 336 and a second pressure relief valve 337. Specifically, the third one-way valve 336 is arranged in the oil circuit connecting the rotary valve 32 and the EF port, and the oil outlet of the third one-way valve 336 is connected to the EF port, so that the oil circuit where the third one-way valve 336 is located is unidirectionally conducted from the rotary valve 32 to the EF port, so as to prevent the hydraulic oil in the external hydraulic system from flowing into the priority valve 3 when the EF port is connected to the external hydraulic system. The second pressure relief valve 337 is connected to the oil inlet and oil outlet of the third one-way valve 336 through the oil circuit, and the oil outlet of the second pressure relief valve 337 is connected to the second oil return port 312, so that when the pressure of the hydraulic oil flowing to the EF port is too large, the excess hydraulic oil is led to the second oil return port 312 through the second pressure relief valve 337 and discharged into the oil return device to achieve pressure relief. Among them, the second pressure relief valve 337 can be connected to the second oil return port 312 connected to the first pressure relief valve 332 through the oil circuit, as shown in FIG. Figure 5 In the example, of course, two second oil return ports 312 can also be provided, connected to the first pressure relief valve 332 and the second pressure relief valve 337, respectively. Figure 6 Examples in .

[0057] like Figure 4 and Figure 6 As shown, the swing control valve assembly 2 is internally equipped with a control valve 22, a shuttle valve 23, a first bypass oil circuit 24, a second bypass oil circuit 26, an oil replenishment circuit 25, a buffer oil circuit 28, and a second check valve 27. The control valve 22 is specifically a three-position, six-way directional control valve with six valve ports: a first valve port 221, a second valve port 222, a third valve port 223, a fourth valve port 224, a fifth valve port 225, and a sixth valve port 226. The first valve port 221 is connected to the first oil inlet 211, the third valve port 223 is connected to the first oil return port 212, the fourth valve port 224 is connected to port A via an oil circuit, and the sixth valve port 226 is connected to port B via an oil circuit. The control valve 22 is connected to the control oil circuit 29. The swing control valve assembly 2 is provided with corresponding ports C and D, which communicate with the ends of the control oil circuit 29, respectively, for connecting to the pilot hydraulic system to drive the control valve 22 for reversing direction.

[0058] A shuttle valve 23 is disposed between the two oil circuits connecting ports A and B. One oil inlet of the shuttle valve 23 connects to the oil circuit connecting port A, while the other oil inlet of the shuttle valve 23 connects to the oil circuit connecting port B. The oil outlet of the shuttle valve 23 connects to a first bypass oil circuit 24, the other end of which is connected to a second valve port 222 of the control valve 22. A second throttle valve 241 and a high-pressure unloading valve 242 are connected to the first bypass oil circuit 24. One end of the oil supply circuit 25 connects to the oil circuit connecting port A, while the other end connects to the oil circuit connecting port B. Two first check valves 251, disposed opposite each other, are connected to the oil supply circuit 25. The fifth valve port 225 of the control valve 22 connects to the oil supply circuit 25 between the two first check valves 251 via an oil circuit. The buffer oil circuit 28 is connected in parallel with the oil replenishment circuit 25. One end of the buffer oil circuit 28 is connected to the oil circuit connected to port A, and the other end is connected to the oil circuit connected to port B. Two buffer valves 281, each arranged in opposite directions, are connected to the buffer oil circuit 28, each with a one-way flow function. The second bypass oil circuit 26 is connected in parallel with the first bypass oil circuit 24. One end of the second bypass oil circuit 26 is connected to the oil outlet of the shuttle valve 23, and the other end is connected to the first bypass oil circuit 24 between the high-pressure unloading valve 242 and the control valve 22. A first reversing valve 261 is connected to the second bypass oil circuit 26 to control the flow of the second bypass oil circuit 26. A second one-way valve 27 is located at the first oil return port 212, and the control valve 22 provides one-way flow from the second one-way valve 27 to the first oil return port 212.

[0059] Under normal conditions, the first reversing valve 261 is in the disconnected state. When the control valve 22 is in the left position, the middle position, and the right position, the connection relationship between the six valve ports is different. Specifically, when the control valve 22 is in the left position, the first valve port 221 is unidirectionally conducted to the fourth valve port 224, the second valve port 222 and the sixth valve port 226 are both throttled to the third valve port 223, and the fifth valve port 225 is closed. At this time, the oil supply circuit 41 supplies oil to the rotary control valve group 2 normally, and the hydraulic oil flows to the A port through the first valve port 221 and the fourth valve port 224 of the control valve 22, and then flows into the hydraulic motor 11, driving the hydraulic motor 11 to output torque. Afterwards, the hydraulic oil flows to the sixth valve port 226 of the control valve 22 through the B port. At this time, most of the hydraulic oil flows to the first return oil port 212 after throttling, and a small part of the hydraulic oil flows into the LS port of the priority valve 3 through the regulating oil circuit 42 after throttling to transmit pressure to the rotary valve 32. Information; when the control valve 22 is in the right position, the first valve port 221 is unidirectionally conducted to the sixth valve port 226, the second valve port 222 and the fourth valve port 224 are both throttled and conducted to the third valve port 223, and the fifth valve port 225 is closed. At this time, the oil supply circuit 41 supplies oil to the rotary control valve group 2 normally, and the hydraulic oil flows to the B port through the first valve port 221 and the sixth valve port 226 of the control valve 22, and then flows into the hydraulic motor 11, driving the hydraulic motor 11 to output torque. Afterwards, the hydraulic oil flows to the fourth valve port 224 of the control valve 22 through the A port. At this time, most of the hydraulic oil flows to the first return oil port 212 after throttling, and a small part of the hydraulic oil flows into the LS port of the priority valve 3 through the regulating oil circuit 42 after throttling to transmit pressure information to the rotary valve 32. Among them, when the control valve 22 is in the left position or the right position, if the hydraulic oil flow to the hydraulic motor 11 is large, a part of the hydraulic oil can flow into the first bypass oil circuit 24 through the shuttle valve 23, and after throttling by the second throttle valve 241, the high-pressure unloading valve 242 is opened, and the hydraulic oil flows into the control valve 22 through the second valve port 222, and then flows to the first return oil port 212 after throttling to achieve unloading.

[0060] When the control valve 22 is in the middle position, the second valve port 222 is connected to the fifth valve port 225, and the other four valve ports are closed. At this time, the rotary control valve group 2 is in the disconnected state, and only the first bypass oil circuit 24 is connected to the oil supply circuit 25. Since the hydraulic motor 11 will continue to rotate for a period of time under the action of inertia, the flow rate of the hydraulic oil between port A and port B will be different, and the flow rate on the return oil side is greater than the flow rate on the supply side. The shuttle valve 23 can allow a part of the hydraulic oil on the return oil side to flow into the first bypass oil circuit 24. After throttling by the second throttle valve 241, the high-pressure unloading valve 242 is opened, and the hydraulic oil in the first bypass oil circuit 24 flows into the supply side through the oil supply circuit, so that the flow rate on the supply side and the return oil side of the hydraulic motor 11 remains relatively balanced, so as to balance the flow rate of the hydraulic oil on both sides of the hydraulic motor 11.

[0061] When the hydraulic motor 11 is operating normally, the first reversing valve 261 is in the open position, and the second reversing valve 335 is switched to connect the LS port to the first orifice 333. When the hydraulic motor 11 switches to the free-swing state, the first reversing valve 261 is switched to the open position, and the second reversing valve 335 is switched to connect the LS port to the third bypass oil passage 34. At this point, the LS port is connected to the second orifice 334 via the third bypass oil passage 34. The pressure at the end of the rotary valve 32 near the first orifice 333 is much lower than the pressure at the end near the second orifice 334. Under the action of pressure, the rotary valve 32 moves to the second position. Hydraulic oil is preferentially supplied to the external hydraulic system through the EF port, and oil supply to the swing control valve assembly 2 is stopped. The hydraulic motor 11 stops outputting torque and enters the free-swing state, allowing it to freely swing according to the rotation requirements of the swing mechanism 5.

[0062] Among them, when the hydraulic motor 11 just switches to the free rotation state, due to inertia, the hydraulic motor 11 will continue to rotate for a period of time. At this time, there may be a pressure difference between the two ends of the hydraulic motor 11. The buffer oil circuit 28 can be used to allow part of the hydraulic oil on the higher pressure side to flow into the lower pressure side to balance the pressure on both sides of the hydraulic motor 11 and eliminate the pressure difference, so that the hydraulic motor 11 can achieve free rotation.

[0063] The rotary hydraulic system in this embodiment can simultaneously drive the rotary mechanism 5 and the external hydraulic system. When the hydraulic motor 11 is in operation, it preferentially supplies oil to the hydraulic motor 11 while diverting excess hydraulic oil to the external hydraulic system to drive the external hydraulic system. This reduces heating caused by excessive oil supply to the hydraulic motor 11, thereby improving the efficiency of hydraulic oil use and reducing energy loss. Furthermore, adaptive flow regulation can be implemented based on the load of the rotary mechanism 5, ensuring that the oil supply is always adapted to the load of the rotary mechanism 5. This reduces the impact pressure in the oil circuit during starting and stopping, allowing the hydraulic motor 11 to operate smoothly and effectively alleviating the shaking of the rotary mechanism 5 during starting and stopping, thereby improving the operational stability of the rotary mechanism 5. Furthermore, the rotary hydraulic system in this embodiment can also achieve free rotation of the hydraulic motor 11 to adapt to the rotation requirements of the rotary mechanism 5.

[0064] Compared with the solution of using proportional valves to adjust the oil supply in existing hydraulic systems, the oil supply adjustment accuracy of the rotary hydraulic system of the present invention is higher, which is beneficial to reducing system heat and energy loss, and can output excess flow to the external hydraulic system while adjusting the oil supply, thereby improving the system's working efficiency.

[0065] In one embodiment of the present invention, there is also provided an engineering machine, such as Figure 1As shown, the engineering machinery includes a slewing mechanism 5 and a slewing hydraulic system in any of the above-mentioned embodiments. The torque output device 1 of the slewing hydraulic system is in transmission connection with the slewing mechanism 5 so as to output torque to the slewing mechanism 5 when the slewing hydraulic system is working, thereby driving the slewing mechanism 5 to rotate. Among them, the priority valve 3 and the slewing control valve group 2 in the slewing hydraulic system can preferentially supply oil to the torque output device 1 to preferentially drive the slewing mechanism 5 to rotate, and adjust the oil supply according to the load size of the slewing mechanism 5, so that the oil supply is always adapted to the demand of the torque output device 1, that is, matched with the load size of the slewing mechanism 5, to achieve accurate adjustment of the oil supply, which is conducive to improving work efficiency, reducing system heat generation, and reducing energy loss. In addition, when the priority valve 3 of the slewing hydraulic system is connected to an external hydraulic system, it can also divert excess hydraulic oil to the external hydraulic system, thereby further improving the utilization rate of the hydraulic oil, which is conducive to further improving work efficiency.

[0066] Furthermore, the engineering machinery includes but is not limited to a crane, wherein the crane may specifically be a wheeled crane.

[0067] In addition, the engineering machinery in this embodiment also has all the beneficial effects of the rotary hydraulic system in any of the above embodiments, which will not be described in detail here.

[0068] The basic principles of the present invention have been described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, and effects mentioned in the present invention are merely illustrative and non-limiting, and should not be construed as necessarily possessed by each embodiment of the present invention. Furthermore, the specific details disclosed above are provided for illustrative purposes and to facilitate understanding, and are not intended to be limiting. These details do not necessarily limit the present invention to being implemented using these specific details.

[0069] The block diagrams of the devices, apparatuses, equipment, and systems involved in the present invention are intended only as illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, or configured in any manner. Words such as "include," "comprise," "have," and the like are open-ended words, meaning "including but not limited to," and can be used interchangeably therewith. The words "or" and "and" used herein refer to the words "and / or" and can be used interchangeably therewith, unless the context clearly indicates otherwise. The word "such as" used herein refers to the phrase "such as but not limited to," and can be used interchangeably therewith. It should also be noted that in the apparatus and equipment of the present invention, the various components can be decomposed and / or recombined. These decompositions and / or recombinations should be considered equivalents of the present invention.

[0070] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present invention. Therefore, the present invention is not intended to be limited to the aspects shown herein, but rather to be applied in the widest sense consistent with the principles and novel features of the invention herein. The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A rotary hydraulic system, characterized in that: include: A torque output device (1) for driving a load to rotate; A rotary control valve group (2) is connected to the torque output device (1) through an oil circuit; a priority valve (3) connected to the rotary control valve group (2) through an oil circuit, wherein the priority valve (3) is capable of adjusting the oil supply according to the flow demand of the torque output device (1); The torque output device (1) includes a hydraulic motor (11); The rotary control valve group (2) is provided with a first oil inlet (211), a first oil return port (212), a first connecting port (213) and a second connecting port (214); the first connecting port (213) is communicated with an oil port of the hydraulic motor (11), and the second connecting port (214) is communicated with another oil port of the hydraulic motor (11); The priority valve (3) is connected to the first oil inlet (211) via an oil supply oil circuit (41) to supply oil to the swing control valve group (2); the priority valve (3) is connected to the oil circuit connected to the first oil return port (212) in the swing control valve group (2) via an adjustment oil circuit (42); The priority valve (3) is provided with a second oil inlet (311), a second oil return port (312), a third connecting port (313), a fourth connecting port (314), a fifth connecting port (315) and a rotary valve (32); The second oil inlet (311) is used to connect to the oil supply device for oil intake, the third connection port (313) is communicated with the oil supply oil circuit (41), the fourth connection port (314) is used to connect to an external hydraulic system, the fifth connection port (315) is communicated with the regulating oil circuit (42), the fifth connection port (315) is connected to the second oil return port (312) through an oil circuit, and a first throttle valve (331) and a first pressure relief valve (332) are provided in the oil circuit connecting the fifth connection port (315) and the second oil return port (312), the rotary valve (32) is connected to the oil circuit connecting the fifth connection port (315) and the first throttle valve (331) through a first throttle hole (333), and the rotary valve (32) is connected to the oil circuit connecting the rotary valve (32) and the third connection port (313) through a second throttle hole (334); The rotary valve (32) is provided with a first position near the first throttle hole (333), and a second position near the second throttle hole (334). The rotary valve (32) can move between the first position and the second position to adjust the flow rate in the oil supply circuit (41). When the rotary valve (32) is in the first position, the second oil inlet (311) is connected to the third connecting port (313), and the fourth connecting port (314) is closed. When the rotary valve (32) is in the first position, the second oil inlet (311) is connected to the third connecting port (313), and the fourth connecting port (314) is closed. When the rotary valve (32) moves toward the second position, the second oil inlet (311) is connected with both the third connecting port (313) and the fourth connecting port (314), and the oil supply to the third connecting port (313) gradually decreases, while the oil supply to the fourth connecting port (314) gradually increases; when the rotary valve (32) is in the second position, the second oil inlet (311) is connected with both the third connecting port (313) and the fourth connecting port (314), and the second oil inlet (311) preferentially supplies oil to the fourth connecting port (314).

2. The rotary hydraulic system according to claim 1, characterized in that: The priority valve (3) further comprises: a third one-way valve (336) connected to the oil circuit between the fourth connecting port (314) and the rotary valve (32), and an oil outlet of the third one-way valve (336) is in communication with the fourth connecting port (314); The second pressure relief valve (337) is connected to the oil inlet and oil outlet of the third one-way valve (336) through an oil circuit, and the oil outlet of the second pressure relief valve (337) is connected to the second oil return port (312).

3. The rotary hydraulic system according to claim 1, characterized in that: The rotary control valve group (2) comprises: A control valve (22), the control valve (22) being a three-position reversing valve, for controlling the flow direction of the hydraulic oil flowing through the hydraulic motor (11); a shuttle valve (23), wherein one oil inlet of the shuttle valve (23) is connected to an oil circuit connected to the first connecting port (213), and another oil inlet of the shuttle valve (23) is connected to an oil circuit connected to the second connecting port (214); a first bypass oil circuit (24), one end of which is connected to the oil outlet of the shuttle valve (23) and the other end of which is connected to the control valve (22); a second throttle valve (241) and a high-pressure unloading valve (242) are connected to the first bypass oil circuit (24); an oil supply oil circuit (25), one end of which is connected to the oil circuit connected to the first connecting port (213), and the other end of which is connected to the oil circuit connected to the second connecting port (214); two first one-way valves (251) arranged opposite to each other are connected to the oil supply oil circuit (25); When the control valve (22) is in the middle position, the first bypass oil circuit (24) is connected to the position between the two first one-way valves (251) in the oil supply oil circuit (25); when the control valve (22) is in the left position or the right position, the first bypass oil circuit (24) is connected to the oil circuit connected to the first oil return port (212).

4. The rotary hydraulic system according to claim 3, characterized in that: The control valve (22) is provided with a first valve port (221), a second valve port (222), a third valve port (223), a fourth valve port (224), a fifth valve port (225) and a sixth valve port (226); the first valve port (221) is connected to the first oil inlet port (211); the second valve port (222) is connected to the first bypass oil circuit (24); the third valve port (223) is connected to the first oil return port (212); the fourth valve port (224) is connected to the first connecting port (213) via an oil circuit; the fifth valve port (225) is connected to a position between the two first one-way valves (251) in the oil supply circuit (25) via an oil circuit; and the sixth valve port (226) is connected to the second connecting port (214) via an oil circuit; The control valve (22) is connected to a control oil circuit (29) for connecting to a pilot hydraulic system to control the reversing of the control valve (22); when the control valve (22) is in a neutral position, the second valve port (222) is connected to the fifth valve port (225); when the control valve (22) is in a left position, the first valve port (221) is unidirectionally connected to the fourth valve port (224), and the second valve port (222) and the sixth valve port (226) are both throttled and connected to the third valve port (223); when the control valve (22) is in a right position, the first valve port (221) is unidirectionally connected to the sixth valve port (226), and the second valve port (222) and the fourth valve port (224) are both throttled and connected to the third valve port (223).

5. The rotary hydraulic system according to claim 3, characterized in that: The rotary control valve group (2) further comprises: A second one-way valve (27) is provided at the first oil return port (212), and the second one-way valve (27) is unidirectionally connected from the control valve (22) to the first oil return port (212).

6. The rotary hydraulic system according to claim 3, characterized in that: The rotary control valve group (2) further comprises: The buffer oil circuit (28) has one end connected to the oil circuit connected to the first connection port (213), and the other end connected to the oil circuit connected to the second connection port (214). Two buffer valves (281) arranged opposite to each other are connected to the buffer oil circuit (28).

7. The rotary hydraulic system according to any one of claims 3 to 6, characterized in that: The rotary control valve group (2) further includes a second bypass oil circuit (26), one end of the second bypass oil circuit (26) is connected to the oil outlet of the shuttle valve (23), and the other end of the second bypass oil circuit (26) is connected to the first bypass oil circuit (24) between the high-pressure unloading valve (242) and the control valve (22), and a first reversing valve (261) is provided in the second bypass oil circuit (26) for controlling the conduction or disconnection of the second bypass oil circuit (26); The priority valve (3) further includes a second reversing valve (335), which is arranged at the fifth connecting port (315) and is connected to the second throttle hole (334) via a third bypass oil circuit (34); the second reversing valve (335) is used to control the communication between the fifth connecting port (315) and the first throttle hole (333); or the second reversing valve (335) is used to control the communication between the fifth connecting port (315) and the third bypass oil circuit (34).

8. An engineering machine, characterized in that: include: Rotating mechanism (5); The rotary hydraulic system according to any one of claims 1 to 7, wherein the torque output device (1) of the rotary hydraulic system is transmission-connected to the rotary mechanism (5) to drive the rotary mechanism (5) to rotate.

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