Rotary action hydraulic control system, rotary action control method and rotary drilling rig

Abstract

A rotary action hydraulic control system comprises a pump, a main valve, a rotary motor and a rotary cushion valve set, an oil inlet of the pump is connected with an oil tank, an oil outlet of the pump is connected to an oil inlet P of the main valve, and a first working oil port A of the main valve is connected to one oil port of the rotary motor through a first oil way; a second working oil port B of the main valve is connected to the other oil port of the rotary motor through a second oil way; the rotary cushion valve group is arranged on the first oil way and the second oil way and comprises a first cushion valve and a second cushion valve, an oil inlet of the first cushion valve is connected to the first oil way, an oil inlet of the second cushion valve is connected to the second oil way, and an oil outlet of the first cushion valve is connected with an oil outlet of the second cushion valve; the first cushion valve has first opening pressure and second opening pressure, and the second opening pressure is larger than the first opening pressure; the second cushion valve has third opening pressure and fourth opening pressure, and the fourth opening pressure is larger than the third opening pressure. The invention further relates to a rotary action control method and a rotary drilling rig.

Description

Technical Field

[0001] The invention relates to the field of pile foundation construction equipment, and in particular to a rotary motion hydraulic control system, a rotary motion control method and a rotary drilling rig. Background Art

[0002] The rotary action of the rotary drilling rig refers to the rotation of the rotary device of the drilling rig driven by the power device, thereby driving the drill rod equipped with the drill bit to rotate, so that the drill bit can cut soil or rock. Specifically, the working principle of the rotary drilling rig is to provide operating power through its engine system, transmit power to the power head through the hydraulic system, and the power head rotates to drive the drill bit to rotate. At the same time, the pressurization system provides pressure, which is transmitted to the drill bit through the drill rod, so that the drill bit can cut and crush the rock and soil.

[0003] The rotary action of the rotary drilling rig can be achieved by handle control, foot pedal control, remote control, etc., but no matter which control method is used, the power must be transmitted to the power head through the rotary action hydraulic control system to perform the rotary action.

[0004] Figure 1 This is a schematic diagram of an existing rotary action hydraulic control system, such as Figure 1 As shown, the rotary action hydraulic control system includes a pump 1, a main valve 2, a balance valve 3 and a rotary motor 4, and two buffer valves are arranged in the balance valve 3. Among them, the engine drives the pump 1. When the operator presses the rotary unlock button and operates the left rotary, the brake oil enters from the PG port, causing the spring to contract and relieve the brake; at the same time, the pilot oil pushes the valve core of the main valve 2 to the working position, and the oil output by the pump 1 enters the V1 port of the balance valve 3, reaches the C1 port through the one-way valve, reaches the A1 port of the rotary motor 4, and flows back to the C2 port of the balance valve through the oil outlet B1 port of the rotary motor 4. At the same time, another oil line reaches the buffer valve pressure regulating valve on the right side of the balance valve 3 as the pilot oil, so that the opening pressure of the balance valve 3 is only controlled by the spring 3a of the right buffer valve, and the opening pressure is 120bar; when the pressure from the B1 to C2 ports reaches 120bar, the oil circuit is connected, so that the oil output of the rotary motor 4 flows back to the main valve 2 from the balance valve V2 port, and then returns to the oil tank;

[0005] When operating the right swing, the brake oil enters from the PG port to contract the spring and release the brake; at the same time, the pilot oil pushes the valve core of the main valve 2 to the working position, and the oil output by the pump 1 enters the V2 port of the balance valve 3, reaches the C2 port through the one-way valve, reaches the B1 port of the swing motor 4, and flows back to the C1 port of the balance valve 3 through the oil outlet A1 port of the swing motor 4. At the same time, another line of oil reaches the pressure regulating valve of the left buffer valve of the balance valve 3 as the pilot oil, so that the opening pressure of the balance valve 3 is only controlled by the spring 3a of the left buffer valve, and the opening pressure is 120bar; when the pressure from the A1 to C1 ports reaches 120bar, the oil circuit is connected, so that the oil output of the swing motor 4 flows back to the main valve core 2 from the V1 port of the balance valve, and then returns to the oil tank.

[0006] However, in actual applications, when the rotary motion hydraulic control system is started, due to the opening pressure, it needs to reach 120bar so that the return oil circuit of the buffer valve can be opened. The response has a certain lag and is accompanied by jitter, which is not smooth enough. In addition, the braking or buffer pressure of the rotary motion hydraulic control system cannot be adjusted, and it is impossible to meet the needs of multiple working conditions. Summary of the invention

[0007] In view of this, the present invention provides a rotary motion hydraulic control system, a rotary motion control method and a rotary drilling rig, which are used to solve the above-mentioned problems.

[0008] A rotary action hydraulic control system provided by an embodiment of the present invention comprises a pump, a main valve, a rotary motor and a rotary buffer valve group, wherein the oil inlet of the pump is connected to an oil tank, the oil outlet of the pump is connected to an oil inlet P of the main valve, the first working oil port A of the main valve is connected to one of the oil ports of the rotary motor through a first oil circuit, and the second working oil port B of the main valve is connected to another oil port of the rotary motor through a second oil circuit; the rotary buffer valve group is arranged on the first oil circuit and the second oil circuit, the rotary buffer valve group comprises a first buffer valve and a second buffer valve, the oil inlet of the first buffer valve is connected to the first oil circuit, the oil inlet of the second buffer valve is connected to the second oil circuit, and the oil outlet of the first buffer valve is connected to the oil outlet of the second buffer valve; the first buffer valve has a first opening pressure and a second opening pressure, wherein the second opening pressure is greater than the first opening pressure; the second buffer valve has a third opening pressure and a fourth opening pressure, wherein the fourth opening pressure is greater than the third opening pressure.

[0009] Furthermore, it also includes a pilot oil circuit, which includes a pilot oil circuit including a pilot control valve and a pilot pump, the oil inlet of the pilot control valve is connected to the oil tank via the pilot pump, the first working oil port A2 of the pilot control valve is connected to the pilot control end of the first buffer valve through the first pilot oil circuit, and when the first pilot oil circuit is connected, the opening pressure of the first buffer valve is adjusted from the first opening pressure to the second opening pressure; the second working oil port B2 oil circuit of the pilot control valve is connected to the pilot control end of the second buffer valve through the second pilot oil circuit, and when the second pilot oil circuit is connected, the opening pressure of the second buffer valve is adjusted from the third opening pressure to the fourth opening pressure.

[0010] Further, the pilot control valve has a first working position, a second working position and a middle position; when the pilot control valve is in the first working position, the oil inlet P2 of the pilot control valve is connected with the first working oil port A2 of the pilot control valve, and the second working oil port B2 of the pilot control valve is connected with the oil return port T2 of the pilot control valve; when the pilot control valve is in the second working position, the oil inlet P2 of the pilot control valve is connected with the second working oil port B2 of the pilot control valve, and the first working oil port A2 of the pilot control valve is connected with the oil return port T2 of the pilot control valve; when the pilot control valve is in the middle position, the first working oil port A2 and the second working oil port B2 of the pilot control valve are both connected with the oil return port T2 of the pilot control valve; the oil return port T2 of the pilot control valve is connected back to the oil tank.

[0011] Further, the main valve has a first working position, a second working position and a middle position; when the main valve is in the first working position, the oil inlet P of the main valve is connected to the first working oil port A of the main valve, and the second working oil port B of the main valve is connected to the oil return port T of the main valve; when the main valve is in the second working position, the oil inlet P of the main valve is connected to the second working oil port B of the main valve, and the first working oil port A of the main valve is connected to the oil return port T of the main valve; when the main valve is in the middle position, the first working oil port A and the second working oil port B of the main valve are both disconnected from the oil return port T of the main valve; the oil return port T of the main valve is connected back to the oil tank.

[0012] Furthermore, the rotary buffer valve group also includes a first one-way valve and a second one-way valve, the oil outlet of the first one-way valve is connected to the first oil circuit, the oil outlet of the second one-way valve is connected to the second oil circuit, and the oil inlets of the first one-way valve and the second one-way valve are connected to the oil tank through an oil replenishing circuit.

[0013] Furthermore, the rotary motor is provided with a brake.

[0014] The invention also provides a method for controlling a rotary motion, which is controlled by the above-mentioned rotary motion hydraulic control system, wherein the rotary motor has a left rotary motion and a right rotary motion, and the control method comprises:

[0015] When the rotary motor starts to perform a left rotary action, or when the rotary motor needs to increase the rotary torque during the left rotary action, the first oil circuit is controlled to supply oil and the second oil circuit is controlled to return oil, and the opening pressure of the first buffer valve is controlled to be adjusted from the first opening pressure to the second opening pressure; when the rotary motor needs to increase the braking force, the first oil circuit and the second oil circuit are controlled to be disconnected, and the opening pressure of the second buffer valve is controlled to be adjusted from the third opening pressure to the fourth opening pressure;

[0016] When the rotary motor starts to perform the right rotary action, or when the rotary motor needs to increase the rotary torque during the right rotary action, the second oil circuit is controlled to supply oil and the first oil circuit is controlled to return oil, and the opening pressure of the second buffer valve is controlled to be adjusted from the third opening pressure to the fourth opening pressure; when the rotary motor needs to increase the braking force, the first oil circuit and the second oil circuit are controlled to be disconnected, and the opening pressure of the first buffer valve is controlled to be adjusted from the first opening pressure to the second opening pressure.

[0017] Further, when the rotary action hydraulic control system is provided with the pilot oil circuit, when it is necessary to control the opening pressure of the first buffer valve to be adjusted from the first opening pressure to the second opening pressure, the first pilot oil circuit is controlled to be open; when it is necessary to control the opening pressure of the second buffer valve to be adjusted from the third opening pressure to the fourth opening pressure, the second pilot oil circuit is controlled to be open.

[0018] Further, the first opening pressure is equal to the third opening pressure, and the second opening pressure is equal to the fourth opening pressure.

[0019] The invention also provides a rotary drilling rig, comprising the above-mentioned rotary action hydraulic control system.

[0020] In summary, the rotary action hydraulic control system of the present invention includes a pump, a main valve, a rotary motor and a rotary buffer valve group, the oil inlet of the pump is connected to the oil tank, the oil outlet of the pump is connected to the oil inlet P of the main valve, the first working oil port A of the main valve is connected to one of the oil ports of the rotary motor through the first oil circuit, and the second working oil port B of the main valve is connected to the other oil port of the rotary motor through the second oil circuit; the rotary buffer valve group is arranged in the first oil circuit and the second oil circuit, the rotary buffer valve group includes a first buffer valve and a second buffer valve, the oil inlet of the first buffer valve is connected to the first oil circuit, the oil inlet of the second buffer valve is connected to the second oil circuit, and the oil outlet of the first buffer valve is connected to the oil outlet of the second buffer valve; the first buffer valve has a first opening pressure and a second opening pressure, wherein the second opening pressure is greater than the first opening pressure; the second buffer valve has a third opening pressure and a fourth opening pressure, wherein the fourth opening pressure is greater than the third opening pressure. The rotary action hydraulic control system drives the rotary motor to rotate by increasing the hydraulic oil pressure at one end of the oil inlet of the rotary motor, thereby increasing its rotary torque to cope with the situation where the equipment needs a larger rotary torque. By controlling the on-off of the first pilot oil circuit or the second pilot oil circuit, the overflow pressure of the first buffer valve or the second buffer valve is increased or reduced, thereby providing a two-speed rotary driving force for the rotary drilling rig. At the same time, when the rotary action hydraulic control system is just started when the rotary action is executed, whether in a low gear or a high gear, the first buffer valve or the second buffer valve has a higher opening pressure relative to the current load condition. The first buffer valve or the second buffer valve is not opened, and the hydraulic oil directly reaches the rotary motor from the first oil circuit or the second oil circuit, and when it flows out of the rotary motor, it flows directly to the return oil position of the main valve through the second oil circuit or the first oil circuit without passing through any opening device, thereby effectively reducing the dead zone stroke of the handle, starting smoothly and quickly, and improving the micro-motion performance of the rotary action. Furthermore, when the main engine needs to stop rotating, the handle is in the middle position, and the main valve is in the middle closed state. The rotation speed of the rotary motor is slowed down by increasing the hydraulic oil pressure at one end of the oil outlet of the rotary motor. When it is about to stop, the brake oil is controlled to be unloaded. When the brake brakes the rotary motor, if the first buffer valve or the second buffer valve is in the low position (that is, the first buffer valve has the first opening pressure and the second buffer valve has the third opening pressure), the overflow pressure is low, and the pressure from the rotary motor to the second working oil port B or the first working oil port A of the main valve is also low, and the braking is smoother, but the braking time will be increased; if the braking effect is not ideal, the second buffer valve or the first buffer valve can be raised to a high position (that is, the second buffer valve has the fourth opening pressure and the first buffer valve has the second opening pressure) to increase the overflow pressure, thereby increasing the braking force of the rotary motor, reducing the braking time, and stopping more quickly, so that when the main engine performs a rotary brake, the braking force of the rotary motor has two adjustable gears to meet more operating conditions.

[0021] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of an existing rotary action hydraulic control system.

[0023] Figure 2 It is a schematic diagram of a rotary action hydraulic control system according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the present invention is described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0025] Figure 2 This is a schematic diagram of a rotary action hydraulic control system of a preferred embodiment of the present invention, please refer to Figure 2 The rotary motion hydraulic control system provided in this embodiment can be applied to a rotary drilling rig. The rotary motion hydraulic control system includes a pump 10, a main valve 20, a rotary motor 30 and a rotary buffer valve group 40.

[0026] Specifically, the pump 10 is a flow-adjustable hydraulic pump, which is driven by the engine 11 . The oil inlet of the pump 10 is connected to the oil tank 100 , and the oil outlet of the pump 10 is connected to the oil inlet P of the main valve 20 .

[0027] The first working oil port A of the main valve 20 is connected to one oil port of the swing motor 30 through the first oil passage 101 , and the second working oil port B of the main valve 20 is connected to the other oil port of the swing motor 30 through the second oil passage 102 .

[0028] In this embodiment, the main valve 20 is a three-position four-way reversing valve. The main valve 20 has a first working position, a second working position and a middle position. When the main valve 20 is in the first working position, the oil inlet P of the main valve 20 is connected to the first working oil port A of the main valve 20, and the second working oil port B of the main valve 20 is connected to the oil return port T of the main valve 20; when the main valve 20 is in the second working position, the oil inlet P of the main valve 20 is connected to the second working oil port B of the main valve 20, and the first working oil port A of the main valve 20 is connected to the oil return port T of the main valve 20; when the main valve 20 is in the middle position, the first working oil port A and the second working oil port B of the main valve 20 are disconnected from the oil return port T of the main valve 20; the oil return port T of the main valve 20 is connected to the oil tank 100.

[0029] The rotary motor 30 is driven by hydraulic oil of a certain pressure and flow rate to generate continuous torque and rotary motion, thereby converting the input hydraulic oil pressure into mechanical energy of rotational motion, so that the rotary motor 30 of the rotary drilling rig can achieve rotary motion. The hydraulic oil is pumped out by the pump 10 and provided to the rotary motor 30 through the first oil circuit 101 or the second oil circuit 102.

[0030] The rotary buffer valve group 40 is arranged on the first oil circuit 101 and the second oil circuit 102. The rotary buffer valve group 40 includes a first buffer valve 41 and a second buffer valve 42. The oil inlet of the first buffer valve 41 is connected to the first oil circuit 101, the oil inlet of the second buffer valve 42 is connected to the second oil circuit 102, and the oil outlet of the first buffer valve 41 is connected to the oil outlet of the second buffer valve 42. The first buffer valve 41 has two different opening pressures, namely, a first opening pressure and a second opening pressure, wherein the second opening pressure is greater than the first opening pressure, and the hydraulic oil in the first oil circuit 101 can have different pressures by adjusting the first buffer valve 41 to have different opening pressures; the second buffer valve 42 has two different opening pressures, namely, a third opening pressure and a fourth opening pressure, wherein the fourth opening pressure is greater than the third opening pressure, and the hydraulic oil in the second oil circuit 102 can have different pressures by adjusting the second buffer valve 42 to have different opening pressures.

[0031] The first buffer valve 41 and the second buffer valve 42 are both overflow valves with pressure boosters. The opening pressure of the first buffer valve 41 and the second buffer valve 42 can be adjusted by hydraulic oil control, manual adjustment, electromagnetic control adjustment, etc.

[0032] In this embodiment, the first buffer valve 41 is provided with a pilot control end 411, and the second buffer valve 42 is provided with a pilot control end 421. The pilot control ends 411 and 421 both have hydraulically controlled springs. The stiffness and elastic retraction force of the springs are controlled by inputting pilot hydraulic oil, so that the hydraulically controlled springs of the pilot control ends 411 and 421 have a lower opening pressure when the pilot hydraulic oil is not input, and have a higher opening pressure after the pilot hydraulic oil is input. Therefore, the rotary action hydraulic control system also includes a pilot oil circuit 50, the pilot oil circuit 50 includes a pilot control valve 51 and a pilot pump 52, the oil inlet of the pilot control valve 51 is connected to the oil tank 100 via the pilot pump 52, the first working oil port A2 of the pilot control valve 51 is connected to the pilot control end 411 of the first buffer valve 41 through the first pilot oil circuit 53, when the first pilot oil circuit 53 is connected, the opening pressure of the first buffer valve 41 is adjusted from the first opening pressure to the second opening pressure; the second working oil port B2 oil circuit of the pilot control valve 51 is connected to the pilot control end 421 of the second buffer valve 42 through the second pilot oil circuit 54, when the second pilot oil circuit 54 is connected, the opening pressure of the second buffer valve 42 is adjusted from the third opening pressure to the fourth opening pressure.

[0033] Furthermore, the pilot control valve 51 is a three-position four-way electromagnetic reversing valve, and its working position is controlled by controlling the power supply and loss of the electromagnets at both ends. The pilot control valve 51 has a first working position, a second working position and a middle position; when the pilot control valve 51 is in the first working position, the oil inlet P2 of the pilot control valve 51 is connected with the first working oil port A2 of the pilot control valve 51, and the second working oil port B2 of the pilot control valve 51 is connected with the oil return port T2 of the pilot control valve 51; when the pilot control valve 51 is in the second working position, the oil inlet P2 of the pilot control valve 51 is connected with the second working oil port B2 of the pilot control valve 51, and the first working oil port A2 of the pilot control valve 51 is connected with the oil return port T2 of the pilot control valve 51; when the pilot control valve 51 is in the middle position, the first working oil port A2 and the second working oil port B2 of the pilot control valve 51 are both connected with the oil return port T2 of the pilot control valve 51; the oil return port T2 of the pilot control valve 51 is connected to the return oil tank 100.

[0034] Furthermore, the rotary buffer valve group 40 further includes a first one-way valve 43 and a second one-way valve 44, the oil outlet of the first one-way valve 43 is connected to the first oil circuit 101, specifically, the oil circuit between the main valve 20 and the first buffer valve 41. The oil outlet of the second one-way valve 44 is connected to the second oil circuit 102, specifically, the oil circuit between the main valve 20 and the first buffer valve 42. The oil inlets of the first one-way valve 43 and the second one-way valve 44 are connected to the oil tank 100 through the oil replenishment circuit 103. When the hydraulic oil in the first oil circuit 101 and the second oil circuit 102 is insufficient, oil can be replenished through the oil replenishment circuit 103.

[0035] Furthermore, the first buffer valve 41, the second buffer valve 42, the first check valve 43 and the second check valve 44 of the rotary buffer valve group 40 are integrated in a housing, the first oil circuit 101 and the second oil circuit 10 include partial oil circuits arranged in the rotary buffer valve group 40, and the rotary buffer valve group 40 is also provided with a plurality of connecting ports for connecting to the main valve 20, the rotary motor 30 and the pilot control valve 51, such as being connected to the first working oil port A of the main valve 20 through the A1 port, being connected to the second working oil port B of the main valve 20 through the B1 port, being connected to the first working oil port A2 of the pilot control valve 51 through the C2 port, and being connected to the second working oil port B2 of the pilot control valve 51 through the D2 port.

[0036] Furthermore, a brake 31 is provided on the rotary motor 30. The brake 31 is connected with brake oil for controlling the magnitude of the braking force. When the braking force is greater than the rotation torque of the rotary motor 30, the rotary motor 30 will stop rotating. When the rotation needs to be resumed, adjusting the amount of brake oil will reduce the braking force, so that the rotary motor 30 resumes rotation.

[0037] The present invention also relates to a rotary motion control method, which is controlled by the above-mentioned rotary motion hydraulic control system. The rotary motor 30 has a left rotary motion and a right rotary motion. The control method includes:

[0038] When the swing motor 30 starts to perform the left swing action, or when the swing motor 30 needs to increase the swing torque during the left swing action, the first oil circuit 101 is controlled to deliver oil and the second oil circuit 102 is controlled to return oil, and the opening pressure of the first buffer valve 41 is controlled to be adjusted from the first opening pressure to the second opening pressure; when the swing motor 30 needs to increase the braking force, the first oil circuit 101 and the second oil circuit 102 are controlled to be disconnected, and the opening pressure of the second buffer valve 42 is controlled to be adjusted from the third opening pressure to the fourth opening pressure;

[0039] When the rotary motor 30 starts to perform the right rotary action, or when the rotary motor 30 needs to increase the rotary torque during the right rotary action, the second oil circuit 102 is controlled to supply oil and the first oil circuit 101 is controlled to return oil, and the opening pressure of the second buffer valve 42 is controlled to be adjusted from the third opening pressure to the fourth opening pressure; when the rotary motor 30 needs to increase the braking force, the first oil circuit 101 and the second oil circuit 102 are controlled to be disconnected, and the opening pressure of the first buffer valve 41 is controlled to be adjusted from the first opening pressure to the second opening pressure.

[0040] The overflow valve adjusts and controls the pressure of the hydraulic oil at one end of the oil inlet through the pressure of the spring. When the pressure of the hydraulic oil exceeds the pressure of the spring (i.e., the opening pressure), the valve core is lifted by the hydraulic oil, and the hydraulic oil flows out of the oil outlet of the overflow valve. If the pressure of the hydraulic oil is less than or equal to the spring pressure, the valve core moves to the position of sealing the hydraulic oil inlet under the elastic force of the spring.

[0041] In this embodiment, a hydraulic control spring is arranged at the pilot control end 411 of the first buffer valve 41 and the pilot control end 421 of the second buffer valve 42 to control the two different opening pressures. Therefore, when the rotary action hydraulic control system is provided with a pilot oil circuit 50, when it is necessary to control the opening pressure of the first buffer valve 41 to be adjusted from the first opening pressure to the second opening pressure, the first pilot oil circuit 53 is controlled to be opened; when it is necessary to control the opening pressure of the second buffer valve 42 to be adjusted from the third opening pressure to the fourth opening pressure, the second pilot oil circuit 54 is controlled to be opened. Among them, the first opening pressure is the initial opening pressure when the pilot hydraulic oil is not introduced into the pilot control end 411 of the first buffer valve 41. When the first pilot oil circuit 53 is opened, the stiffness and elastic retraction force of the spring at the pilot control end 411 of the first buffer valve 41 are enhanced, and the first buffer valve 41 has the adjusted second opening pressure. Similarly, the third opening pressure is the initial opening pressure when the pilot hydraulic oil is not introduced into the pilot control end 421 of the second buffer valve 42. When the second pilot oil circuit 54 is connected, the stiffness and elastic retraction force of the spring of the pilot control end 421 of the second buffer valve 42 are enhanced, and the second buffer valve 41 has the adjusted fourth opening pressure.

[0042] The rotary action hydraulic control system of this embodiment drives the rotary motor 30 to rotate by increasing the hydraulic oil pressure at one end of the oil inlet of the rotary motor 30, thereby increasing its rotary torque to cope with the situation where the equipment needs a larger rotary torque. By controlling the on-off of the first pilot oil circuit 53 or the second pilot oil circuit 54, the overflow pressure of the first buffer valve 41 or the second buffer valve 42 is increased or decreased, thereby providing a two-speed rotary driving force for the rotary drilling rig. At the same time, when the rotary action hydraulic control system is just started when the rotary action is executed, whether in the low gear or in the high gear, the rotary action hydraulic control system is turned on and off. In the high gear, the first buffer valve 41 or the second buffer valve 42 has a higher opening pressure relative to the current load condition. The first buffer valve 41 or the second buffer valve 42 is not opened, and the hydraulic oil directly reaches the rotary motor 30 from the first oil circuit 101 or the second oil circuit 102, and when it flows out from the rotary motor 30, it directly flows to the return oil position of the main valve 20 through the second oil circuit 102 or the first oil circuit 101 without passing through any opening device, thereby effectively reducing the dead zone stroke of the handle, starting smoothly and quickly, and improving the micro-motion performance of the rotary action. Furthermore, when the main engine needs to be rotated and stopped, the handle is in the middle position, the main valve 20 is in the middle closed state, and the rotation speed of the rotary motor 30 is slowed down by increasing the hydraulic oil pressure at one end of the oil outlet of the rotary motor 30. When it is about to stop, the brake oil is controlled to be unloaded, and the brake 31 brakes the rotary motor 30. At this time, if the first buffer valve 41 or the second buffer valve 42 is in the low position (that is, the first buffer valve 41 has a first opening pressure, and the second buffer valve 42 has a third opening pressure), the overflow pressure is low, and the rotary motor 30 to the second working position of the main valve 20 is The pressure of the oil port B or the first working oil port A is also relatively low, and the braking is smoother, but the braking time will be increased; if the braking effect is not ideal, the second buffer valve 42 or the first buffer valve 41 can be raised to a high position (that is, the second buffer valve 42 has the fourth opening pressure and the first buffer valve 41 has the second opening pressure) to increase the overflow pressure, thereby increasing the braking force of the swing motor 30, reducing the braking time, and stopping more quickly, so that when the main engine performs swing braking, the braking force of the swing motor 30 has two adjustable gears to meet more operating conditions.

[0043] The first opening pressure, the second opening pressure, the third opening pressure and the fourth opening pressure can be set appropriately according to the usage. Further, the first opening pressure is equal to the third opening pressure, and the second opening pressure is equal to the fourth opening pressure. In this embodiment, the second opening pressure and the fourth opening pressure are both 260 bar.

[0044] The specific control process of the rotary action hydraulic control system of the present invention is as follows:

[0045] When the operator operates the equipment to make a left rotation, the brake oil enters the brake 31 by rotating the unlock button to release the brake. The engine 11 drives the pump 10 to output hydraulic oil, which enters the A1 port of the rotary buffer valve group 40 through the valve core of the main valve 20 (moves to the first working position). At the same time, the pilot control valve 51 moves to the left (first working position), so that the hydraulic oil output by the pilot pump 52 enters the C2 port of the rotary buffer valve group 40, and the first buffer valve 41 switches to the high overflow pressure (i.e., the second opening pressure) position. At this time, the overflow pressure is 260bar. The oil circuit of the A1 port of the rotary buffer valve group 40 will not pass through the first buffer valve 41, but directly connect to the rotary motor 30, and flow directly from the oil outlet of the rotary motor 30 to the B1 port of the rotary buffer valve group 40, and then return to the oil tank 100 through the valve core of the main valve 20. When the rotary action is stopped, that is, after the main valve 20 returns to the middle position, the braking speed of the rotary motor 30 can be controlled by controlling whether the pilot control valve 51 moves to the right (the second working position) and whether the second buffer valve 42 is in the high-pressure overflow position.

[0046] When the operator operates the equipment to make a right rotation, the brake oil enters the brake 31 through the rotation unlock button to release the brake; the engine 11 drives the pump 10 to output hydraulic oil, which moves through the valve core of the main valve 20 (moves into the first working position) and enters the B1 port of the rotary buffer valve group 40. At the same time, the pilot control valve 51 moves to the right (the second working position), so that the hydraulic oil output by the pilot pump 52 enters the D2 port of the rotary buffer valve group 40, so that the second buffer valve 42 switches to the high overflow pressure (i.e., the fourth opening pressure) position. At this time, the overflow pressure is 260 bar, and the oil circuit of the B1 port of the rotary buffer valve group 40 does not pass through the second buffer valve 42, but is directly connected to the rotary motor 30, and flows directly from the oil outlet of the rotary motor 30 to the A1 port of the rotary buffer valve group 40, and then returns to the oil tank 100 through the valve core of the main valve 20. When the rotary action is stopped, that is, after the main valve 20 returns to the middle position, the braking speed of the rotary motor 30 can be controlled by controlling whether the pilot control valve 51 moves to the left (first working position) and whether the first buffer valve 41 is in the high-pressure overflow position.

[0047] The present invention also relates to a rotary drilling rig, comprising the above rotary motion hydraulic control system. Other structures of the rotary drilling rig are well known to those skilled in the art and will not be described in detail here.

[0048] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A rotary motion hydraulic control system, comprising a pump (10), a main valve (20), a rotary motor (30) and a rotary buffer valve group (40), characterized in that: The oil inlet of the pump (10) is connected to the oil tank (100), the oil outlet of the pump (10) is connected to the oil inlet P of the main valve (20), the first working oil port A of the main valve (20) is connected to one of the oil ports of the rotary motor (30) through a first oil circuit (101), and the second working oil port B of the main valve (20) is connected to the other oil port of the rotary motor (30) through a second oil circuit (102); the rotary buffer valve group (40) is arranged on the first oil circuit (101) and the second oil circuit (102), and the rotary buffer valve group (40) includes a first buffer valve ( The first buffer valve (41) is a first buffer valve (41) and a second buffer valve (42), wherein the oil inlet of the first buffer valve (41) is connected to the first oil circuit (101), the oil inlet of the second buffer valve (42) is connected to the second oil circuit (102), and the oil outlet of the first buffer valve (41) is connected to the oil outlet of the second buffer valve (42); the first buffer valve (41) has a first opening pressure and a second opening pressure, wherein the second opening pressure is greater than the first opening pressure; the second buffer valve (42) has a third opening pressure and a fourth opening pressure, wherein the fourth opening pressure is greater than the third opening pressure.

2. The rotary motion hydraulic control system according to claim 1, characterized in that: The invention also comprises a pilot oil circuit (50), wherein the pilot oil circuit (50) comprises a pilot control valve (51) and a pilot pump (52), wherein the oil inlet of the pilot control valve (51) is connected to the oil tank (100) via the pilot pump (52), and the first working oil port A2 of the pilot control valve (51) is connected to the pilot control end (411) of the first buffer valve (41) via the first pilot oil circuit (53), and when the first pilot oil circuit (53) is connected, the opening pressure of the first buffer valve (41) is adjusted from the first opening pressure to the second opening pressure; and the second working oil port B2 of the pilot control valve (51) is connected to the pilot control end (421) of the second buffer valve (42) via the second pilot oil circuit (54), and when the second pilot oil circuit (54) is connected, the opening pressure of the second buffer valve (42) is adjusted from the third opening pressure to the fourth opening pressure.

3. The rotary motion hydraulic control system according to claim 2, characterized in that: The pilot control valve (51) has a first working position, a second working position and a neutral position; when the pilot control valve (51) is in the first working position, the oil inlet P2 of the pilot control valve (51) is in communication with the first working oil port A2 of the pilot control valve (51), and the second working oil port B2 of the pilot control valve (51) is in communication with the oil return port T2 of the pilot control valve (51); when the pilot control valve (51) is in the second working position, the oil inlet P2 of the pilot control valve (51) is in communication with the first working oil port A2 of the pilot control valve (51), and the second working oil port B2 of the pilot control valve (51) is in communication with the oil return port T2 of the pilot control valve (51). P2 is connected to the second working oil port B2 of the pilot control valve (51), and the first working oil port A2 of the pilot control valve (51) is connected to the oil return port T2 of the pilot control valve (51); when the pilot control valve (51) is in the middle position, the first working oil port A2 and the second working oil port B2 of the pilot control valve (51) are both connected to the oil return port T2 of the pilot control valve (51); and the oil return port T2 of the pilot control valve (51) is connected back to the oil tank (100).

4. The rotary motion hydraulic control system according to claim 2 or 3, characterized in that: The main valve (20) has a first working position, a second working position and a middle position; when the main valve (20) is in the first working position, the oil inlet P of the main valve (20) is connected to the first working oil port A of the main valve (20), and the second working oil port B of the main valve (20) is connected to the oil return port T of the main valve (20); when the main valve (20) is in the second working position, the oil inlet P of the main valve (20) is connected to the second working oil port B of the main valve (20), and the first working oil port A of the main valve (20) is connected to the oil return port T of the main valve (20); when the main valve (20) is in the middle position, the first working oil port A and the second working oil port B of the main valve (20) are both disconnected from the oil return port T of the main valve (20); the oil return port T of the main valve (20) is connected back to the oil tank (100).

5. The rotary motion hydraulic control system according to claim 1, characterized in that: The rotary buffer valve group (40) also includes a first one-way valve (43) and a second one-way valve (44), wherein the oil outlet of the first one-way valve (43) is connected to the first oil circuit (101), the oil outlet of the second one-way valve (44) is connected to the second oil circuit (102), and the oil inlets of the first one-way valve (43) and the second one-way valve (44) are connected to the oil tank (100) via an oil replenishing circuit (103).

6. The rotary motion hydraulic control system according to claim 1, characterized in that: The rotary motor (30) is provided with a brake (31).

7. A method for controlling a rotation motion, characterized in that: The rotary motor (30) is controlled by the rotary action hydraulic control system according to any one of claims 1 to 6, and has a left rotary action and a right rotary action. The control method comprises: When the rotary motor (30) starts to perform a left rotary action, or when the rotary motor (30) needs to increase the rotary torque during the left rotary action, the first oil circuit (101) is controlled to deliver oil and the second oil circuit (102) is controlled to return oil, and at the same time, the opening pressure of the first buffer valve (41) is controlled to be adjusted from the first opening pressure to the second opening pressure; when the rotary motor (30) needs to increase the braking force, the first oil circuit (101) and the second oil circuit (102) are controlled to be disconnected, and at the same time, the opening pressure of the second buffer valve (42) is controlled to be adjusted from the third opening pressure to the fourth opening pressure; When the rotary motor (30) is started to perform a right rotary action, or when the rotary motor (30) needs to increase the rotary torque during the right rotary action, the second oil circuit (102) is controlled to deliver oil and the first oil circuit (101) is controlled to return oil, and at the same time, the opening pressure of the second buffer valve (42) is controlled to be adjusted from the third opening pressure to the fourth opening pressure; when the rotary motor (30) needs to increase the braking force, the first oil circuit (101) and the second oil circuit (102) are controlled to be disconnected, and at the same time, the opening pressure of the first buffer valve (41) is controlled to be adjusted from the first opening pressure to the second opening pressure.

8. The rotary motion hydraulic control system according to claim 7, characterized in that: When the rotary action hydraulic control system is provided with the pilot oil circuit (50), when it is necessary to control the opening pressure of the first buffer valve (41) to be adjusted from the first opening pressure to the second opening pressure, the first pilot oil circuit (53) is controlled to be open; when it is necessary to control the opening pressure of the second buffer valve (42) to be adjusted from the third opening pressure to the fourth opening pressure, the second pilot oil circuit (54) is controlled to be open.

9. The rotary motion hydraulic control system according to claim 7, characterized in that: The first opening pressure is equal to the third opening pressure, and the second opening pressure is equal to the fourth opening pressure.

10. A rotary drilling rig, characterized in that: Comprising a rotary motion hydraulic control system as described in any one of claims 1 to 6.

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