A hydraulic control circuit for push-pull rotary drive

Abstract

The application discloses a hydraulic control circuit of push-pull rotary drive, comprising: electro-hydraulic reversing valve, hydraulic control check valve, shift fork device, hydraulic reversing valve and actuator; the electro-hydraulic reversing valve is provided with first electro-hydraulic working oil port and second electro-hydraulic working oil port; the hydraulic control check valve comprises: first hydraulic control check valve and second hydraulic control check valve; the shift fork device is internally provided with shift fork assembly, and the shift fork assembly divides the shift fork device into shift fork left cavity and shift fork right cavity; the hydraulic reversing valve is provided with first hydraulic working oil port and second hydraulic working oil port; the control oil port of the hydraulic reversing valve is communicated with the first electro-hydraulic working oil port or the second electro-hydraulic working oil port; the internal cavity of the actuator is provided with moving piston, and the moving piston divides the internal cavity of the actuator into rodless cavity and rod cavity. The hydraulic control circuit can reduce the required torque of rotation and reduce the wear of the matching surface.

Description

Technical Field

[0001] This invention relates to the field of rotary valve drive control technology, and more specifically to a push-pull rotary drive hydraulic control circuit. Background Technology

[0002] Under normal circumstances, when a plug valve is sealing, a force with the large end of the cone pointing towards the small end of the cone needs to be provided in the direction perpendicular to the pipeline to make the sealing mating surface tightly fit with the valve core. When the plug valve rotates, due to the existence of this force, a large frictional torque will be generated. At this time, a large torque is required to drive the plug valve, and the rotation of the valve core can easily cause wear on the sealing mating surface.

[0003] Therefore, developing a hydraulic control circuit for push-pull rotary drive that reduces the torque required for rotation and minimizes wear on mating surfaces is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the present invention provides a hydraulic control circuit for push-pull rotary drive that reduces the torque required for rotation and reduces wear on mating surfaces.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A push-pull rotary drive hydraulic control circuit, comprising:

[0007] An electro-hydraulic directional valve is provided with a first electro-hydraulic working port and a second electro-hydraulic working port; the pressure port and return port of the electro-hydraulic directional valve are respectively connected to the pressure port and return port of an external hydraulic source.

[0008] A hydraulically controlled check valve, comprising: a first hydraulically controlled check valve and a second hydraulically controlled check valve; the inlet of the first hydraulically controlled check valve is connected to the first electro-hydraulic working port; the control port of the first hydraulically controlled check valve is connected to the second electro-hydraulic working port; the control port of the second hydraulically controlled check valve is connected to the first electro-hydraulic working port; and the inlet of the second hydraulically controlled check valve is connected to the second electro-hydraulic working port.

[0009] A shift fork device, wherein a shift fork assembly is provided inside the shift fork device, the shift fork assembly connecting the shift fork device to a left shift fork chamber and a right shift fork chamber respectively; the oil outlet of a first hydraulic check valve is connected to the left shift fork chamber, and the oil outlet of a second hydraulic check valve is connected to the right shift fork chamber.

[0010] A hydraulic directional valve, wherein the pressure port and return port of the hydraulic directional valve are respectively connected to the pressure port and return port of an external hydraulic source; the hydraulic directional valve is provided with a first hydraulic working port and a second hydraulic working port; the control port of the hydraulic directional valve is connected to the first electro-hydraulic working port or the second electro-hydraulic working port.

[0011] An actuating device is provided inside the actuating device, which divides the inner cavity of the actuating device into a rodless cavity and a rod cavity; the first hydraulic working port of the hydraulic directional valve is connected to the rodless cavity, and the second hydraulic working port is connected to the rod cavity.

[0012] The beneficial effects of adopting the above technical solution are that the fork device can output rotational torque to realize the rotation drive of the valve, and the actuation device provides force for valve sealing. The rotation and sealing of the valve are carried out separately, which can reduce the wear of the sealing mating surface and effectively improve the service life of the plug valve.

[0013] Preferably, the shift fork assembly includes: a shift fork piston, a connecting rod, and a shift fork; both ends of the connecting rod are connected to the shift fork piston, the top of the shift fork is rotatably connected to the inner cavity of the shift fork device, the bottom of the shift fork is provided with a sliding groove, a slider is provided on the connecting rod, the slider is placed in the sliding groove and slides in the sliding groove; a rotating shaft is fixed to the top of the shift fork to transmit rotational torque to the outside. Driven by hydraulic oil, the shift fork piston can move left and right, thereby driving the shift fork to rotate and swing, realizing the conversion of the reciprocating motion of the shift fork piston into the rotational motion of the shift fork, and outputting rotational torque to drive the valve to rotate.

[0014] Preferably, the oil outlet of the first hydraulic check valve is connected to a first one-way throttle valve, and the oil outlet of the first one-way throttle valve is connected to the left chamber of the shift fork. Adjusting the opening and closing of the first one-way throttle valve can regulate the pressure required to drive the shift fork device.

[0015] Preferably, the outlet of the second hydraulic check valve is connected to a second one-way throttle valve, and the outlet of the second one-way throttle valve is connected to the right chamber of the shift fork. Adjusting the opening and closing of the second one-way throttle valve allows for regulation of the pressure required to drive the shift fork device.

[0016] Preferably, a shuttle valve is provided between the electro-hydraulic directional valve and the hydraulically controlled directional valve. The first and second electro-hydraulic working ports are respectively connected to the two inlets of the shuttle valve; the outlet of the shuttle valve is connected to the control port of the hydraulically controlled directional valve. The shuttle valve can select the hydraulic oil output from the first and second electro-hydraulic working ports, with the hydraulic oil with higher pressure passing through the shuttle valve.

[0017] Preferably, the movable piston is connected to a piston rod, the piston rod is placed in the rod chamber, and the end of the piston rod away from the movable piston passes through the rod chamber and outputs thrust or pull force to the outside.

[0018] Preferably, when opening or closing the plug valve, the pressure required to drive the output torque of the shift fork device is higher than the pressure required to drive the output pull force of the actuating device. Whether opening or closing the plug valve, the actuating device must first drive the output pull force to separate the sealing mating surface from the valve core before driving the shift fork device to rotate. This effectively reduces wear on the mating surfaces.

[0019] As can be seen from the above technical solution, compared with the prior art, the present invention discloses a push-pull rotary drive hydraulic control circuit, the beneficial effects of which are:

[0020] (1) In this invention, by controlling the shift fork device and the actuating device, the valve rotation can be driven, and the force required for valve sealing can be provided. This not only reduces the driving torque during rotation drive, but also reduces the wear of mating surfaces, thereby improving the operational reliability and sealing life of the equipment.

[0021] (2) The hydraulic control circuit can be remotely controlled, which facilitates the automation of the system. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0023] Figure 1 A schematic diagram of the hydraulic control circuit provided by the present invention.

[0024] 1-Electro-hydraulic directional valve;

[0025] 11-First electro-hydraulic working oil port; 12-Second electro-hydraulic working oil port;

[0026] 2-First hydraulic check valve; 3-Second hydraulic check valve;

[0027] 4-Shift fork device;

[0028] 41-Left chamber of the shift fork; 42-Right chamber of the shift fork; 43-Shift fork piston; 44-Connecting rod; 45-Shift fork; 46-Slide groove; 47-Slider;

[0029] 5-Hydraulic directional valve;

[0030] 51-First hydraulic working port; 52-Second hydraulic working port;

[0031] 6-Actuating device;

[0032] 61-Moving piston; 62-Rodless chamber; 63-Rod chamber; 64-Piston rod;

[0033] 7-First one-way throttle valve; 8-Second one-way throttle valve; 9-Shuttle valve. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] This invention discloses a push-pull rotary drive hydraulic control circuit, comprising:

[0036] The electro-hydraulic directional valve 1 is provided with a first electro-hydraulic working port 11 and a second electro-hydraulic working port 12; the pressure port and return port of the electro-hydraulic directional valve 1 are respectively connected to the pressure port and return port of an external hydraulic source.

[0037] The hydraulically controlled check valve includes: a first hydraulically controlled check valve 2 and a second hydraulically controlled check valve 3; the oil inlet of the first hydraulically controlled check valve 2 is connected to the first electro-hydraulic working oil port 11; the control oil port of the first hydraulically controlled check valve 2 is connected to the second electro-hydraulic working oil port 12; the control oil port of the second hydraulically controlled check valve 3 is connected to the first electro-hydraulic working oil port 11; and the oil inlet of the second hydraulically controlled check valve 3 is connected to the second electro-hydraulic working oil port 12.

[0038] The shift fork device 4 has a shift fork assembly inside, which divides the inside of the shift fork device 4 into a left shift fork chamber 41 and a right shift fork chamber 42; the oil outlet of the first hydraulic check valve 2 is connected to the left shift fork chamber 41, and the oil outlet of the second hydraulic check valve 3 is connected to the right shift fork chamber 42.

[0039] The hydraulic directional valve 5 has a pressure port and a return port that are respectively connected to the pressure port and return port of an external hydraulic source. The hydraulic directional valve 5 is provided with a first hydraulic working port 51 and a second hydraulic working port 52. The control port of the hydraulic directional valve 5 is connected to the first electro-hydraulic working port 11 or the second electro-hydraulic working port 12.

[0040] The actuator 6 contains a movable piston 61, which divides the internal cavity of the actuator 6 into a rodless chamber 62 and a rod chamber 63. The first hydraulic working port 51 of the hydraulic directional valve 5 is connected to the rodless chamber 62, and the second hydraulic working port 52 is connected to the rod chamber 63. Under normal circumstances, the actuator 6 always outputs thrust. When the valve is rotated, regardless of the direction of rotation, the actuator 6 is always in a pulling state. This ensures that the rotational torque is reduced during rotational actuation and also reduces wear on the sealing surfaces.

[0041] To further optimize the above technical solution, the shift fork assembly includes: a shift fork piston 43, a connecting rod 44, and a shift fork 45; the two ends of the connecting rod 44 are respectively connected to the shift fork piston 43, the top of the shift fork 45 is rotatably connected to the inner cavity of the shift fork device 4, the bottom of the shift fork 45 is provided with a sliding groove 46, a slider 47 is provided on the connecting rod 44, the slider 47 is placed in the sliding groove 46 and slides in the sliding groove 46; a rotating shaft is fixed on the top of the shift fork 45 to transmit rotational torque to the outside.

[0042] To further optimize the above technical solution, the oil outlet of the first hydraulic check valve 2 is connected to a first one-way throttle valve 7, and the oil outlet of the first one-way throttle valve 7 is connected to the left chamber 41 of the shift fork. By adjusting the first hydraulic check valve 2 and the second hydraulic check valve 3, a certain back pressure can be generated to adjust the pressure required to drive the shift fork device 4. When the shift fork piston 43 needs to move to the right chamber 42 of the shift fork, the second hydraulic check valve 3 is adjusted; when the shift fork piston 43 needs to move to the left chamber 41 of the shift fork, the first hydraulic check valve 2 is adjusted. Regardless of whether the stop valve needs to rotate clockwise or counterclockwise, it first actuates the actuator 6 to output pulling force.

[0043] To further optimize the above technical solution, a second one-way throttle valve 8 is connected to the oil outlet of the second hydraulic check valve 3, and the oil outlet of the second one-way throttle valve 8 is connected to the right chamber 42 of the shift fork. When the pressure at the oil inlet of the first hydraulic check valve 2 and the second hydraulic check valve 3 is 0, the first hydraulic check valve 2 and the second hydraulic check valve 3 achieve one-way locking. Control oil is introduced into the control oil port of the first hydraulic check valve 2 and the second hydraulic check valve 3 to achieve reverse flow control of the first hydraulic check valve 2 and the second hydraulic check valve 3.

[0044] To further optimize the above technical solution, a shuttle valve 9 is provided between the electro-hydraulic directional valve 1 and the hydraulic directional valve 5. The first electro-hydraulic working port 11 and the second electro-hydraulic working port 12 are respectively connected to the two inlets of the shuttle valve 9; the outlet of the shuttle valve 9 is connected to the control port of the hydraulic directional valve 5.

[0045] To further optimize the above technical solution, a piston rod 64 is connected to the movable piston 61. The piston rod 64 is placed in the rod chamber 63, and the end of the piston rod 64 away from the movable piston 61 passes through the rod chamber 63 and outputs thrust or pull force to the outside. When the actuating device 6 outputs thrust force, it seals the stopcock valve; when the actuating device 6 outputs pull force, it releases the seal on the stopcock valve.

[0046] To further optimize the above technical solution, when opening or closing the plug valve, the pressure required for the drive fork device 4 to output torque is higher than the pressure required for the drive actuator 6 to output tension. The actuator 6 is always in the tension output state during rotary drive.

[0047] Working principle:

[0048] The shift fork device 4 converts reciprocating motion into rotary motion and outputs torque to achieve rotary drive. The actuator outputs thrust and pull force through linear reciprocating motion.

[0049] When the electro-hydraulic directional valve 1 is in the neutral position, the control chambers of the first hydraulic check valve 2 and the second hydraulic check valve 3 drain oil, forming a hydraulic lock, and the shift fork device 4 maintains its current position. At this time, the control chamber of the hydraulic directional valve 5 drains oil through the shuttle valve 9 via the neutral position of the electro-hydraulic directional valve 1. The hydraulic directional valve 5 is in the right position under the action of the spring. At this time, the pressure oil input from the external hydraulic source enters the rodless chamber 62 of the actuator 6, and the rod chamber 63 of the actuator 6 is connected to the return port of the external hydraulic source. The actuator 6 outputs thrust to provide the sealing force required.

[0050] When the electro-hydraulic directional valve is switched to the right position, the pressure oil from the external hydraulic source enters the left shift fork chamber 41 of the shift fork device 4 through the electro-hydraulic directional valve 1, the first hydraulic control check valve 2, and the first 7 one-way throttle valve. The right shift fork chamber 42 of the shift fork device 4 is connected to the return port of the external hydraulic source through the second one-way throttle valve 8, the second hydraulic control check valve 3, and the electro-hydraulic directional valve 1. The shift fork piston 43 moves to the right, and is converted into counterclockwise rotational motion by the shift fork 45 and outputs torque. At this time, the first electro-hydraulic working port 11 and the second electro-hydraulic working port 12 of the electro-hydraulic directional valve 1 are connected to the pressure oil and return oil of the external oil source, respectively, and the hydraulic oil is introduced into the shuttle valve 9. The hydraulic oil in the two working ports is compared in the shuttle valve 9 and outputs the higher pressure oil. This pressure oil enters the control chamber of the hydraulic directional valve 5, pushing the hydraulic directional valve 5 to switch to the left position. The pressure oil input from the external hydraulic source enters the rod chamber 63 of the actuator 6. The rodless chamber 62 of the actuator 6 is connected to the return oil of the external hydraulic source. The actuator 6 outputs a pulling force, and the mating surface is in a disengaged state. By adjusting the second one-way throttle valve 8, a certain back pressure is generated to ensure that the pressure required to drive the shift fork device 4 is higher than the minimum pressure required to drive the actuator 6 to output a pulling force. By adjusting the load of the actuator 6, it is ensured that the pressure required to drive the actuator 6 to output a pulling force is higher than the pressure required to drive the hydraulic directional valve 5 to switch. Through the above design, it can be ensured that the actuator 6 moves first and the shift fork device 4 moves later. When the torque is output, the mating surface has already disengaged, and there is no frictional torque, thereby reducing the required driving torque.

[0051] Similarly, when the electro-hydraulic directional valve 1 is switched to the left position, the shift fork device 4 outputs clockwise rotational motion and torque, and the actuating device 6 acts first, followed by the shift fork device 4.

[0052] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0053] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A push-pull rotary drive hydraulic control circuit, characterized in that, include: An electro-hydraulic directional valve (1) is provided with a first electro-hydraulic working port (11) and a second electro-hydraulic working port (12); the pressure port and return port of the electro-hydraulic directional valve (1) are respectively connected to the pressure port and return port of an external hydraulic source. A hydraulically controlled check valve, comprising: a first hydraulically controlled check valve (2) and a second hydraulically controlled check valve (3); the inlet of the first hydraulically controlled check valve (2) is connected to the first electro-hydraulic working port (11); the control port of the first hydraulically controlled check valve (2) is connected to the second electro-hydraulic working port (12); the control port of the second hydraulically controlled check valve (3) is connected to the first electro-hydraulic working port (11); the inlet of the second hydraulically controlled check valve (3) is connected to the second electro-hydraulic working port (12). The shift fork device (4) is provided with a shift fork assembly inside. The shift fork assembly divides the inside of the shift fork device (4) into a left shift fork chamber (41) and a right shift fork chamber (42). The oil outlet of the first hydraulic check valve (2) is connected to the left shift fork chamber (41), and the oil outlet of the second hydraulic check valve (3) is connected to the right shift fork chamber (42). A hydraulic directional valve (5) is provided, wherein the pressure port and return port of the hydraulic directional valve (5) are respectively connected to the pressure port and return port of an external hydraulic source; the hydraulic directional valve (5) is provided with a first hydraulic working port (51) and a second hydraulic working port (52); the control port of the hydraulic directional valve (5) is connected to the first electro-hydraulic working port (11) or the second electro-hydraulic working port (12); a shuttle valve (9) is provided between the electro-hydraulic directional valve (1) and the hydraulic directional valve (5), wherein the first electro-hydraulic working port (11) and the second electro-hydraulic working port (12) are respectively connected to the two inlets of the shuttle valve (9); the outlet of the shuttle valve (9) is connected to the control port of the hydraulic directional valve (5); The actuator (6) has a movable piston (61) inside, which divides the inner cavity of the actuator (6) into a rodless cavity (62) and a rod cavity (63). The first hydraulic working port (51) of the hydraulic directional valve (5) is connected to the rodless cavity (62), and the second hydraulic working port (52) is connected to the rod cavity (63).

2. The push-pull rotary drive hydraulic control circuit according to claim 1, characterized in that, The shift fork assembly includes: a shift fork piston (43), a connecting rod (44), and a shift fork (45); the two ends of the connecting rod (44) are respectively connected to the shift fork piston (43), the top of the shift fork (45) is rotatably connected to the inner cavity of the shift fork device (4), the bottom of the shift fork (45) is provided with a sliding groove (46), a slider (47) is provided on the connecting rod (44), the slider (47) is placed in the sliding groove (46) and slides in the sliding groove (46); the top of the shift fork (45) is fixed with a rotating shaft to transmit rotational torque to the outside.

3. The push-pull rotary drive hydraulic control circuit according to claim 1, characterized in that, The oil outlet of the first hydraulic check valve (2) is connected to the first one-way throttle valve (7), and the oil outlet of the first one-way throttle valve (7) is connected to the left chamber (41) of the shift fork.

4. The push-pull rotary drive hydraulic control circuit according to claim 3, characterized in that, The oil outlet of the second hydraulic control check valve (3) is connected to a second one-way throttle valve (8), and the oil outlet of the second one-way throttle valve (8) is connected to the right chamber (42) of the shift fork.

5. The push-pull rotary drive hydraulic control circuit according to claim 1, characterized in that, The movable piston (61) is connected to a piston rod (64), which is placed in the rod chamber (63). The end of the piston rod (64) away from the movable piston (61) passes through the rod chamber (63) and outputs thrust or pull force to the outside.

6. The push-pull rotary drive hydraulic control circuit according to claim 5, characterized in that, When the plug valve is opened or closed, the pressure required to drive the output torque of the shift fork device (4) is higher than the pressure required to drive the output pull force of the actuating device (6).

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