A valve-controlled ram-type steering gear for inland waterway vessels

Abstract

A valve-controlled plunger rudder for inland river ships, which comprises a first oil cylinder, a second oil cylinder, a third oil cylinder, a fourth oil cylinder, a first control valve block and a second control valve block; the first oil cylinder is connected with the second oil cylinder, the third oil cylinder is connected with the fourth oil cylinder, the third oil cylinder is communicated with a first oil tank, and the fourth oil cylinder is communicated with a second oil tank; a first hydraulic assembly is installed on the side of the first oil tank, the first hydraulic assembly is connected with the first control valve block, a second hydraulic pump is installed on the side of the second oil tank, and the second hydraulic pump is connected with the second control valve block; a first stop valve on the first oil cylinder is connected with the first control valve block, a third stop valve on the third oil cylinder is connected with the first control valve block, a second stop valve on the second oil cylinder is connected with the first control valve block, and a fourth stop valve on the fourth oil cylinder is connected with the first control valve block; the double-plunger multi-cylinder can meet the power demand of the inland river ships.

Description

Technical Field

[0001] This invention relates to an improvement of plunger-type steering technology, belonging to the field of steering gears, and particularly to a valve-controlled plunger-type steering gear suitable for inland waterway vessels. Background Technology

[0002] The steering system is a crucial piece of equipment for ensuring the safe navigation of a ship, used to maintain or change its course. As a core component of the steering system, the rudder gear is subject to stringent reliability requirements from the International Maritime Organization and major classification societies. The plunger-type rudder gear is a steering mechanism with excellent torque characteristics, converting the linear motion of the plunger into the rotational motion of the rudder stick via the rudder handle. Its simple structure, convenient maintenance, and suitability for large-scale applications have made it highly popular among users.

[0003] Existing valve-controlled electro-hydraulic piston steering gears generally adopt a dual-pump station redundant architecture. Each pump station consists of an electric motor, a fixed displacement pump and a valve control unit, which works with the steering mechanism to realize the steering function. Under normal working conditions, a single pump station supplies oil independently.

[0004] Under normal operating conditions, a single hydraulic pump station is used for independent oil supply. The directional delivery and return circulation of pressurized oil are completed by controlling the reversing regulation of the control valve group, which drives the steering mechanism to achieve bidirectional steering control. When the system experiences oil leakage, the automatic isolation diagnostic logic is triggered by the graded liquid level alarm. The faulty unit is located by isolating the pump station one by one. After confirming the fault, it automatically switches to the standby pump station for independent operation, ensuring that the steering gear can continue to work normally even in the case of a single pump station failure. However, under the current conventional operating mode of one pump station in use and one in standby, the output torque of the single plunger double-acting cylinder cannot meet the power requirements of inland waterway vessels.

[0005] Chinese patent application CN201821500988.8, filed on September 14, 2018, discloses a plunger-type steering gear with a closed-loop hydraulic system. The gear includes a base, with a steering gear assembly on the left side of the base. This assembly includes a motor, a plunger pump, and a closed-loop hydraulic system. The closed-loop hydraulic system includes an oil tank, two cylinders, a valve block, and closed-loop hydraulic lines. The oil tank and one of the cylinders are located on the upper left side of the base, while the motor, plunger pump, valve block, and the other cylinder are located on the lower left side of the base. The output shaft of the motor is connected to the plunger pump via a coupling. The closed-loop hydraulic lines include an inlet pipe connecting the oil tank and the two cylinders, and an outlet pipe. This solution uses a closed-loop hydraulic system, a custom-designed hydraulic pump, and auxiliary systems. During steering maneuvers, the hydraulic oil is exchanged within the system, reducing energy consumption to some extent and achieving energy-saving effects. However, this solution still does not solve the problem that a single-plunger double-acting cylinder cannot meet the power requirements of inland waterway vessels.

[0006] The information disclosed in this background section is intended only to enhance the understanding of the overall background of this patent application and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0007] The purpose of this invention is to overcome the problem that the existing single-plunger double-acting cylinder cannot meet the power requirements of inland waterway vessels, and to provide a valve-controlled plunger steering gear suitable for inland waterway vessels that can meet the power requirements of inland waterway vessels with a double-plunger multi-cylinder design.

[0008] To achieve the above objectives, the technical solution of the present invention is: a valve-controlled plunger steering gear suitable for inland waterway vessels, wherein the valve-controlled plunger steering gear suitable for inland waterway vessels includes a first cylinder, a second cylinder, a third cylinder, a fourth cylinder, a first control valve block, and a second control valve block;

[0009] The first hydraulic cylinder is connected to the second hydraulic cylinder through the first plunger assembly, the third hydraulic cylinder is connected to the fourth hydraulic cylinder through the second plunger assembly, the third hydraulic cylinder is connected to the first oil tank, and the fourth hydraulic cylinder is connected to the second oil tank.

[0010] A first hydraulic assembly is installed on the side of the first oil tank and is connected to a first control valve block. A second hydraulic pump is installed on the side of the second oil tank and is connected to a second control valve block.

[0011] The first shut-off valve on the first cylinder is connected to the first control valve block, the third shut-off valve on the third cylinder is connected to the first control valve block, the second shut-off valve on the second cylinder is connected to the first control valve block, and the fourth shut-off valve on the fourth cylinder is connected to the first control valve block.

[0012] The first control valve block includes a first pilot valve, a first switching valve, and a first isolation valve; the second control valve block includes a second isolation valve.

[0013] The oil outlet of the first oil tank is connected to the oil inlet of the first hydraulic pump in the first hydraulic assembly, the oil outlet of the first hydraulic pump is connected to the oil inlet of the first pilot valve, the oil outlet of the first pilot valve is connected to the oil inlet of the first switching valve, and the oil outlet of the first switching valve is connected to the oil inlet of the second oil cylinder.

[0014] The oil outlet of the first switching valve is connected to the oil inlet of the first isolation valve, the oil outlet of the first isolation valve is connected to the oil inlet of the second isolation valve, the oil outlet of the second isolation valve is connected to the oil inlet of the third cylinder via port D, the oil outlet of the first cylinder is connected to the oil inlet of the first switching valve via port A, the oil outlet of the first switching valve is connected to the oil inlet of the first hydraulic pump, and the oil outlet of the first hydraulic pump is connected to the oil inlet of the first oil tank.

[0015] The oil outlet of the fourth cylinder is connected to the oil inlet of the second isolation valve via port C. The oil inlet of the second isolation valve is connected to the oil inlet of the first isolation valve. The oil outlet of the first isolation valve is connected to the oil inlet of the first switching valve.

[0016] The first and third cylinders are connected by a first connecting seat, and the second and fourth cylinders are connected by a second connecting seat.

[0017] A rudder assembly is provided between the first plunger assembly and the second plunger assembly.

[0018] The first and third hydraulic cylinders are arranged symmetrically with the second and fourth hydraulic cylinders and the rudder assembly.

[0019] A first guide rod is installed between the first and second hydraulic cylinders, above the first plunger assembly;

[0020] A second guide rod is installed between the third and fourth cylinders, located below the second plunger assembly.

[0021] A first high-pressure flange is provided at the connection between the first shut-off valve and the first oil cylinder, a second high-pressure flange is provided at the connection between the second shut-off valve and the second oil cylinder, a third high-pressure flange is provided at the connection between the third shut-off valve and the third oil cylinder, and a fourth high-pressure flange is provided at the connection between the fourth shut-off valve and the fourth oil cylinder.

[0022] A first hydraulic assembly is installed on the side of the first oil tank. The first hydraulic assembly is connected to a first control valve block inside the first oil tank through a first internal outfitting pipeline. A second hydraulic pump is installed on the side of the second oil tank. The second hydraulic pump is connected to a second control valve block inside the second oil tank through a second internal outfitting pipeline.

[0023] The first hydraulic assembly also includes a first motor, which is connected to a first hydraulic pump.

[0024] The first control valve block also includes a first safety valve, which is disposed between the oil circuit of the first switching valve and the first isolation valve.

[0025] The control valve block includes a second pilot valve, a second switching valve, and a second safety valve;

[0026] The oil outlet of the second oil tank is connected to the oil inlet of the second hydraulic pump in the second hydraulic assembly. The oil outlet of the second hydraulic pump is connected to the oil inlet of the second pilot valve. The oil outlet of the second pilot valve is connected to the oil inlet of the second switching valve. The oil outlet of the second switching valve is connected to the oil inlet of the first oil cylinder.

[0027] The oil outlet of the second switching valve is connected to the oil inlet of the second isolation valve, the oil outlet of the second isolation valve is connected to the oil inlet of the first isolation valve, the oil outlet of the first isolation valve is connected to the oil inlet of the fourth cylinder via port C, the oil outlet of the second cylinder is connected to the oil inlet of the second switching valve via port B, the oil outlet of the second switching valve is connected to the oil inlet of the second hydraulic pump, and the oil outlet of the second hydraulic pump is connected to the oil inlet of the second oil tank.

[0028] The oil outlet of the third cylinder is connected to the oil inlet of the first isolation valve via port D. The oil outlet of the first isolation valve is connected to the oil inlet of the second isolation valve. The oil outlet of the second isolation valve is connected to the oil inlet of the second switching valve.

[0029] The second safety valve is located between the oil lines of the second switching valve and the second isolation valve.

[0030] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0031] 1. In a valve-controlled plunger-type steering gear suitable for inland waterway vessels, the first cylinder is connected to the second cylinder, the third cylinder is connected to the fourth cylinder, the third cylinder is connected to the first oil tank, and the fourth cylinder is connected to the second oil tank. A first hydraulic assembly is installed on the side of the first oil tank and connected to the first control valve block. A second hydraulic pump is installed on the side of the second oil tank and connected to the second control valve block. A first shut-off valve on the first cylinder is connected to the first control valve block, a third shut-off valve on the third cylinder is connected to the first control valve block, a second shut-off valve on the second cylinder is connected to the first control valve block, and a fourth shut-off valve on the fourth cylinder is connected to the first control valve block. In application, a first motor drives the first hydraulic pump to draw oil from the first oil tank and pressurize it, sending it to the first pilot valve of the first control valve block to establish system oil pressure. Under normal operating conditions, the first isolation valve and the second isolation valve remain open. When the right rudder is executed, the first pilot valve controls the first switch. When the valve is switched to the right position, the high-pressure oil is divided into two paths: one path directly supplies the second cylinder, pushing the first plunger assembly to deflect the lower half of the rudder assembly; the other path supplies the third cylinder via the first and second isolation valves, pushing the second plunger assembly to deflect the upper half of the rudder assembly synchronously. The low-pressure oil from the first and fourth cylinders on the return side flows into the first switching valve through the corresponding passages, and finally returns to the first oil tank, forming a closed loop of synchronous dual-plunger drive. When the left rudder is executed, the first pilot valve controls the first switching valve to switch to the left position, and the oil supply and return paths are reversed, thus achieving reverse steering. When a fault is detected in the third cylinder, fourth cylinder, or second plunger assembly, the first isolation valve reverses and cuts off the oil supply and return paths on both sides, and the second isolation valve opens simultaneously. The actuator on the faulty side is completely disconnected from the main system, and only the first cylinder, second cylinder, and first plunger assembly continue to operate, preserving basic steering capability, preventing fault propagation, and achieving redundant protection.

[0032] Firstly, the single-plunger dual-cylinder structure is upgraded to a four-cylinder dual-plunger symmetrical architecture. The single pump station, through the integrated oil circuit of pilot valve, switching valve, and series isolation valve, enables a single hydraulic pump station to supply oil to two sets of cylinders simultaneously. The high-pressure oil output from the single pump station is divided into two paths after passing through the first switching valve. One path directly supplies oil to the second cylinder on the same side to drive the first plunger assembly to move. The other path passes through the first isolation valve and the second isolation valve in series to supply oil to the third cylinder on the opposite side to drive the second plunger assembly to move synchronously. This enables the single pump station to drive two sets of cylinders to move synchronously when working, and simultaneously supply oil to the cylinders on both sides to drive the dual plungers to push the rudder synchronously. Under the existing space, without increasing the cylinder diameter, without increasing the overall installation volume, and while maintaining the dual pump station one-in-one-out operation mode, the torque requirements for steering of inland waterway vessels are met.

[0033] Secondly, a dual-pump station symmetrical redundancy design is adopted. The hydraulic drive system of the steering gear maintains the original two sets of pump stations for oil supply, and is adjusted to four cylinders with double plunger action. The flow is collected by a combination of electromagnetic pilot valves and switching valves. A single pump station can independently drive all four cylinders to complete bidirectional steering. If one pump station fails, the other can seamlessly take over all functions. With the single-sided actuator isolation mode, in the event of a failure, a single-sided cylinder group can be retained to maintain basic steering capability, forming a dual redundancy protection for the power end and the actuator end.

[0034] Thirdly, during normal operation, one set of pump stations supplies oil while another set is on standby, and they can be freely combined. When entering or leaving a port or in a narrow waterway, both sets of pump stations can supply oil simultaneously to increase the steering speed.

[0035] Fourthly, by arranging the first and second isolation valves in series, the supply and return of oil in the cross-side oil circuit can be controlled simultaneously, achieving complete isolation of the single-side cylinder and plunger actuator. Compared with the traditional multi-valve group pump station isolation scheme, the number of isolation valves used is greatly reduced, the overall oil circuit layout is simplified, the system failure points and manufacturing costs are reduced, and the fault isolation range is extended from the pump station end to the actuator end. In case of actuator end failures such as cylinder leakage and plunger jamming, the fault branch can be cut off to prevent the fault from spreading and improve the system's fault tolerance.

[0036] Therefore, the dual-plunger multi-cylinder design of this invention can meet the power requirements of inland waterway vessels.

[0037] 2. In this invention, a valve-controlled plunger-type steering gear suitable for inland waterway vessels comprises a first hydraulic cylinder connected to a second hydraulic cylinder via a first plunger assembly, and a third hydraulic cylinder connected to a fourth hydraulic cylinder via a second plunger assembly. A rudder handle assembly is disposed between the two sets of plungers. The four hydraulic cylinders and the rudder handle assembly are arranged in a centrally symmetrical manner, constructing a mechanical transmission system with dual-plunger symmetrical drive, providing a structural basis for torque superposition. The centrally symmetrical layout ensures that the rudder handle is subjected to completely balanced forces, with no radial off-center load during deflection, effectively avoiding jamming and uneven wear problems, and improving the smoothness of rudder turning and the accuracy of rudder angle control. Therefore, this invention provides balanced forces and stable accuracy.

[0038] 3. In the valve-controlled plunger-type steering gear of this invention, applicable to inland waterway vessels, the guide rod provides auxiliary guiding support for the reciprocating motion of the plunger, counteracting the radial load generated by the reaction force of the rudder handle, constraining the linear motion trajectory of the plunger, reducing the wear and tear between the plunger and the inner wall of the cylinder and the seals, extending the service life of the seals, and further ensuring the smoothness of the plunger's movement. Therefore, this invention has a long service life and stable operation. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of the present invention.

[0040] Figure 2 This is a schematic diagram of the oil flow path in this invention.

[0041] Figure 3 This is a schematic diagram of the structure of the first control valve block in this invention.

[0042] Figure 4 This is a schematic diagram of the structure of the second control valve block in this invention.

[0043] In the diagram: 1st cylinder, 2nd cylinder, 3rd cylinder, 4th cylinder, 5th plunger assembly, 6th plunger assembly, 7th rudder assembly, 8th oil tank, 9th oil tank, 10th internal outfitting pipeline, 11th internal outfitting pipeline, 12th high-pressure flange, 13th guide rod, 14th guide rod, 15th connecting seat, 16th connecting seat, 17th hydraulic assembly, 171st motor, 172nd hydraulic pump, 18th hydraulic pump, 19th control valve block, 191st pilot valve, 192nd switching valve, 193rd safety valve, 194th isolation valve, 20th control valve block, 201st pilot valve, 202nd switching valve, 203rd safety valve, 204th isolation valve, 21st shut-off valve, 22nd shut-off valve, 23rd shut-off valve, 24th shut-off valve, 25th high-pressure flange, 26th high-pressure flange, 27th high-pressure flange. Detailed Implementation

[0044] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] See Figures 1 to 4 A valve-controlled plunger steering gear suitable for inland waterway vessels, the valve-controlled plunger steering gear suitable for inland waterway vessels includes a first cylinder 1, a second cylinder 2, a third cylinder 3, a fourth cylinder 4, a first control valve block 19 and a second control valve block 20;

[0046] The first hydraulic cylinder 1 is connected to the second hydraulic cylinder 2 through the first plunger assembly 5, the third hydraulic cylinder 3 is connected to the fourth hydraulic cylinder 4 through the second plunger assembly 6, the third hydraulic cylinder 3 is connected to the first oil tank 8, and the fourth hydraulic cylinder 4 is connected to the second oil tank 9.

[0047] A first hydraulic assembly 17 is installed on the side of the first oil tank 8, and the first hydraulic assembly 17 is connected to the first control valve block 19. A second hydraulic pump 18 is installed on the side of the second oil tank 9, and the second hydraulic pump 18 is connected to the second control valve block 20.

[0048] The first shut-off valve 21 on the first cylinder 1 is connected to the first control valve block 19, the third shut-off valve 23 on the third cylinder 3 is connected to the first control valve block 19, the second shut-off valve 22 on the second cylinder 2 is connected to the first control valve block 19, and the fourth shut-off valve 24 on the fourth cylinder 4 is connected to the first control valve block 19.

[0049] The first control valve block 19 includes a first pilot valve 191, a first switching valve 192 and a first isolation valve 194, and the second control valve block 20 includes a second isolation valve 204;

[0050] The oil outlet of the first oil tank 8 is connected to the oil inlet of the first hydraulic pump 172 in the first hydraulic assembly 17. The oil outlet of the first hydraulic pump 172 is connected to the oil inlet of the first pilot valve 191. The oil outlet of the first pilot valve 191 is connected to the oil inlet of the first switching valve 192. The oil outlet of the first switching valve 192 is connected to the oil inlet of the second oil cylinder 2.

[0051] The oil outlet of the first switching valve 192 is connected to the oil inlet of the first isolation valve 194. The oil outlet of the first isolation valve 194 is connected to the oil inlet of the second isolation valve 204. The oil outlet of the second isolation valve 204 is connected to the oil inlet of the third cylinder 3 via port D. The oil outlet of the first cylinder 1 is connected to the oil inlet of the first switching valve 192 via port A. The oil outlet of the first switching valve 192 is connected to the oil inlet of the first hydraulic pump 172. The oil outlet of the first hydraulic pump 172 is connected to the oil inlet of the first oil tank 8.

[0052] The oil outlet of the fourth oil cylinder 4 is connected to the oil inlet of the second isolation valve 204 via port C. The oil inlet of the second isolation valve 204 is connected to the oil inlet of the first isolation valve 194. The oil outlet of the first isolation valve 194 is connected to the oil inlet of the first switching valve 194.

[0053] The first hydraulic cylinder 1 and the third hydraulic cylinder 3 are connected by a first connecting seat 15, and the second hydraulic cylinder 2 and the fourth hydraulic cylinder 4 are connected by a second connecting seat 16.

[0054] A rudder assembly 7 is provided between the first plunger assembly 5 and the second plunger assembly 6.

[0055] The first hydraulic cylinder 1, the third hydraulic cylinder 3, the second hydraulic cylinder 2, the fourth hydraulic cylinder 4, and the rudder assembly 7 are arranged symmetrically around the center.

[0056] A first guide rod 13 is installed between the first hydraulic cylinder 1 and the second hydraulic cylinder 2, above the first plunger assembly 5;

[0057] A second guide rod 14 is installed between the third cylinder 3 and the fourth cylinder 4, located below the second plunger assembly 6.

[0058] A first high-pressure flange 25 is provided at the connection between the first shut-off valve 21 and the first oil cylinder 1; a second high-pressure flange 26 is provided at the connection between the second shut-off valve 22 and the second oil cylinder 2; a third high-pressure flange 27 is provided at the connection between the third shut-off valve 23 and the third oil cylinder 3; and a fourth high-pressure flange 12 is provided at the connection between the fourth shut-off valve 24 and the fourth oil cylinder 4.

[0059] A first hydraulic assembly 17 is installed on the side of the first oil tank 8. The first hydraulic assembly 17 is connected to the first control valve block 19 inside the first oil tank 8 through the first internal outfitting pipeline 10. A second hydraulic pump 18 is installed on the side of the second oil tank 9. The second hydraulic pump 18 is connected to the second control valve block 20 inside the second oil tank 9 through the second internal outfitting pipeline 11.

[0060] The first hydraulic assembly 17 also includes a first motor 171, which is connected to a first hydraulic pump 172.

[0061] The first control valve block 19 further includes a first safety valve 193, which is disposed between the oil circuit of the first switching valve 192 and the first isolation valve 194.

[0062] The control valve block 20 includes a second pilot valve 201, a second switching valve 202 and a second safety valve 203;

[0063] The oil outlet of the second oil tank 9 is connected to the oil inlet of the second hydraulic pump 182 in the second hydraulic assembly 18. The oil outlet of the second hydraulic pump 182 is connected to the oil inlet of the second pilot valve 201. The oil outlet of the second pilot valve 201 is connected to the oil inlet of the second switching valve 202. The oil outlet of the second switching valve 202 is connected to the oil inlet of the first oil cylinder 1.

[0064] The oil outlet of the second switching valve 202 is connected to the oil inlet of the second isolation valve 204. The oil outlet of the second isolation valve 204 is connected to the oil inlet of the first isolation valve 194. The oil outlet of the first isolation valve 194 is connected to the oil inlet of the fourth cylinder 4 via port C. The oil outlet of the second cylinder 2 is connected to the oil inlet of the second switching valve 202 via port B. The oil outlet of the second switching valve 202 is connected to the oil inlet of the second hydraulic pump 182. The oil outlet of the second hydraulic pump 182 is connected to the oil inlet of the second oil tank 9.

[0065] The oil outlet of the third oil cylinder 3 is connected to the oil inlet of the first isolation valve 194 via port D. The oil outlet of the first isolation valve 194 is connected to the oil inlet of the second isolation valve 204. The oil outlet of the second isolation valve 204 is connected to the oil inlet of the second switching valve 202.

[0066] The second safety valve 203 is disposed between the oil circuit of the second switching valve 202 and the second isolation valve 204.

[0067] The supplementary technical features of this design are as follows:

[0068] The first motor 171 is powered on and drives the first hydraulic pump 172 to work, drawing hydraulic oil from the first oil tank 8 through the oil suction port; the hydraulic oil is transported to the first control valve block 19 through the first internal outfitting pipeline 10, and first enters the first pilot valve 191.

[0069] When the right rudder command is executed, the first pilot valve 191 is energized and reversed to the left position. The pilot pressure oil pushes the first switching valve 192 to switch to the right position to work, establishing the main pressure oil circuit, which is divided into two circuits.

[0070] First oil circuit: Drives the second oil cylinder 2. The oil outlet of the first switching valve 192 flows into the second oil cylinder 2 through the second high-pressure flange 26, the second shut-off valve 22, and port B, pushing the second oil cylinder plunger to move to the right.

[0071] The second oil circuit drives the third oil cylinder 3. The oil outlet of the first switching valve 192 flows into the third oil cylinder 3 through the first isolation valve 194, the second isolation valve 204, the third high-pressure flange 27, and the third shut-off valve 23, pushing the third oil cylinder plunger to move to the right synchronously.

[0072] Two high-pressure oil lines simultaneously drive two sets of plungers to move in the same direction, and the roller pulls the rudder handle assembly 7 to deflect clockwise, completing the right rudder action; the first safety valve 193 in the oil circuit stabilizes the pressure in real time and overflows to protect the hydraulic system in case of overload; the low-pressure oil inside the first cylinder 1 flows back to the right-side return oil chamber of the first switching valve 192 through port A, the first high-pressure flange 25, the first shut-off valve 21; the low-pressure oil inside the fourth cylinder 4 flows into the return oil chamber of the first switching valve 192 through port C, the fourth high-pressure flange 12, the fourth shut-off valve 24, the second isolation valve 204, and the first isolation valve 194; after the two return oil lines merge, they are sent to the return oil port of the first hydraulic pump 172 through the return oil section of the first internal outfitting pipeline 10, and finally flow back to the first oil tank 8, completing the closed-loop circulation of hydraulic oil;

[0073] When a left rudder command is sent, the first pilot valve 191 is energized in the right position, which pushes the first switching valve 192 to the left position to switch the direction. The oil supply and return lines are completely reversed from the right rudder, and the hydraulic oil pushes the plunger in the reverse direction. The rudder handle rotates counterclockwise to achieve left rudder. In the isolation mode, the left rudder isolation logic is the same as that of the right rudder.

[0074] Example 1:

[0075] A valve-controlled plunger steering gear suitable for inland waterway vessels, the valve-controlled plunger steering gear suitable for inland waterway vessels includes a first cylinder 1, a second cylinder 2, a third cylinder 3, a fourth cylinder 4, a first control valve block 19 and a second control valve block 20;

[0076] The first hydraulic cylinder 1 is connected to the second hydraulic cylinder 2 through the first plunger assembly 5, the third hydraulic cylinder 3 is connected to the fourth hydraulic cylinder 4 through the second plunger assembly 6, the third hydraulic cylinder 3 is connected to the first oil tank 8, and the fourth hydraulic cylinder 4 is connected to the second oil tank 9.

[0077] A first hydraulic assembly 17 is installed on the side of the first oil tank 8, and the first hydraulic assembly 17 is connected to the first control valve block 19. A second hydraulic pump 18 is installed on the side of the second oil tank 9, and the second hydraulic pump 18 is connected to the second control valve block 20.

[0078] The first shut-off valve 21 on the first cylinder 1 is connected to the first control valve block 19, the third shut-off valve 23 on the third cylinder 3 is connected to the first control valve block 19, the second shut-off valve 22 on the second cylinder 2 is connected to the first control valve block 19, and the fourth shut-off valve 24 on the fourth cylinder 4 is connected to the first control valve block 19.

[0079] The first control valve block 19 includes a first pilot valve 191, a first switching valve 192 and a first isolation valve 194, and the second control valve block 20 includes a second pilot valve 201, a second switching valve 202 and a second isolation valve 204.

[0080] The oil outlet of the first oil tank 8 is connected to the oil inlet of the first hydraulic pump 172 in the first hydraulic assembly 17. The oil outlet of the first hydraulic pump 172 is connected to the oil inlet of the first pilot valve 191. The oil outlet of the first pilot valve 191 is connected to the oil inlet of the first switching valve 192. The oil outlet of the first switching valve 192 is connected to the oil inlet of the second oil cylinder 2.

[0081] The oil outlet of the first switching valve 192 is connected to the oil inlet of the first isolation valve 194. The oil outlet of the first isolation valve 194 is connected to the oil inlet of the second isolation valve 204. The oil outlet of the second isolation valve 204 is connected to the oil inlet of the third cylinder 3 via port D. The oil outlet of the first cylinder 1 is connected to the oil inlet of the first switching valve 192 via port A. The oil outlet of the first switching valve 192 is connected to the oil inlet of the first hydraulic pump 172. The oil outlet of the first hydraulic pump 172 is connected to the oil inlet of the first oil tank 8.

[0082] The oil outlet of the fourth oil cylinder 4 is connected to the oil inlet of the second isolation valve 204 via port C. The oil inlet of the second isolation valve 204 is connected to the oil inlet of the first isolation valve 194. The oil outlet of the first isolation valve 194 is connected to the oil inlet of the first switching valve 194.

[0083] In application: The first motor 171 drives the first hydraulic pump 172 to operate, drawing hydraulic oil from the first oil tank 8. After pressurization, the hydraulic oil is output to the oil inlet of the first pilot valve 191 of the first control valve block 19 to establish the system's basic oil pressure. The first switching valve 192 switches to the right position, and the main oil supply and return oil circuits are officially connected. Under normal operating conditions, both the first isolation valve 194 and the second isolation valve 204 remain open. The high-pressure oil is divided into two paths through the oil outlet of the first switching valve 192 to synchronously drive the two plunger assemblies to ensure that the steering wheel assembly 7 is subjected to balanced force. The first path directly delivers hydraulic oil to the first control valve block 19. The oil enters from port B through the second shut-off valve 22 and the second high-pressure flange 26, pushing the first plunger assembly 5 to move in a specific direction and causing the lower half of the rudder assembly 7 to deflect. The second path passes through the first isolation valve 194 and the second isolation valve 204 in sequence, and is delivered to the oil inlet of the third cylinder 3. It enters from port D through the third shut-off valve 23 and the third high-pressure flange 27, pushing the second plunger assembly 6 to move in the same direction and causing the upper half of the rudder assembly 7 to deflect synchronously. The low-pressure return oil from both cylinders merges and returns to the oil tank to form a complete hydraulic cycle.

[0084] Low-pressure oil in the first cylinder 1 is output from port A, flows back to the return side of the first switching valve 192 via the first high-pressure flange 25 and the first shut-off valve 21. The second path is low-pressure oil in the fourth cylinder 4 output from port C, flows into the second isolation valve 204 via the fourth high-pressure flange 12 and the fourth shut-off valve 24, and then merges into the return side of the first switching valve 192 via the first isolation valve 194. After the two return oil paths merge, they flow back to the first oil tank 8 via the return end of the first hydraulic pump 172. Under this condition, the first cylinder 1, the second cylinder 2, the third cylinder 3, the fourth cylinder 4, the first plunger assembly 5, and the second plunger assembly 6 synchronously drive the rudder assembly 7 to deflect. When the left rudder command is executed, the first pilot valve 191 is energized in the right position, pushing the first switching valve 192 to switch to the left position. The oil supply and return oil paths are completely reversed. The plunger moves in the opposite direction and the rudder assembly 7 deflects in the opposite direction to achieve the left rudder action.

[0085] When the system detects a fault in the third cylinder 3, the fourth cylinder 4, or the second plunger assembly 6, it automatically triggers isolation protection. The first hydraulic assembly 17 continues to operate, retaining only the driving capability of one cylinder to prevent the fault from escalating. At this time, the first hydraulic pump 172 continuously supplies oil, the first pilot valve 191 and the first switching valve 192 maintain the working state corresponding to the right rudder, and the main oil circuit pressure is stable. After receiving the isolation signal, the first isolation valve 194 reverses direction, cutting off its own oil supply branch to the second isolation valve 204 and blocking the return oil passage on the faulty side. The second isolation valve 204 then disconnects from the main oil circuit. The actuators containing the third cylinder 3 and the fourth cylinder 4 are completely disconnected from the main hydraulic system, and high-pressure oil is only delivered to the second cylinder 2 through the first switching valve 192. Only the first hydraulic cylinder 1, the second hydraulic cylinder 2, and the first plunger assembly 5 are driven to work to output basic steering power. On the return oil side, only the low-pressure oil of the first hydraulic cylinder 1 flows back from port A to the first switching valve 192, and finally returns to the first oil tank 8 to form a single-sided closed loop. Under this condition, the faulty side mechanism is completely stopped to avoid jamming, leakage and other faults affecting the operation of the whole machine. At the same time, the minimum steering ability is maintained by relying on the single-sided cylinder to ensure the basic maneuvering requirements of the ship and realize fault redundancy operation. The second control valve block 20, which is composed of the second oil tank 9, the second hydraulic pump 18 and the second control valve block 20, is completely symmetrical with the structure of the first hydraulic assembly 17. As a redundant backup, it can be on standby during normal navigation, or it can work synchronously with the first hydraulic assembly 17 to improve the overall output power.

[0086] Example 2:

[0087] Example 2 is basically the same as Example 1, except that:

[0088] The first hydraulic cylinder 1 is connected to the second hydraulic cylinder 2 via the first plunger assembly 5, and the third hydraulic cylinder 3 is connected to the fourth hydraulic cylinder 4 via the second plunger assembly 6. The first hydraulic cylinder 1 and the third hydraulic cylinder 3 are connected via the first connecting seat 15, and the second hydraulic cylinder 2 and the fourth hydraulic cylinder 4 are connected via the second connecting seat 16. A rudder assembly 7 is provided between the first plunger assembly 5 and the second plunger assembly 6. The first hydraulic cylinder 1, the third hydraulic cylinder 3, the second hydraulic cylinder 2, the fourth hydraulic cylinder 4, and the rudder assembly 7 are centrally symmetrically arranged. A first guide rod 13 is installed above the first plunger assembly 5 between the first hydraulic cylinder 1 and the second hydraulic cylinder 2. A second guide rod 14 is installed below the second plunger assembly 6 between the third hydraulic cylinder 3 and the fourth hydraulic cylinder 4.

[0089] In application: Guide rods are provided between cylinders on the same side: first cylinder 1 and second cylinder 2 are provided with first guide rod 13, and third cylinder 3 and fourth cylinder 4 are provided with second guide rod 14 to constrain the linear movement of the plunger and prevent eccentric loading and jamming; cylinders on opposite sides are fixed by connecting seats. First cylinder 1 and third cylinder 3 are connected by first connecting seat 15, and second cylinder 2 and fourth cylinder 4 are connected by second connecting seat 16. All cylinders are uniformly fixed on a common base.

[0090] Example 3:

[0091] Example 3 is basically the same as Example 1, except that:

[0092] A first high-pressure flange 25 is provided at the connection between the first shut-off valve 21 and the first oil cylinder 1; a second high-pressure flange 26 is provided at the connection between the second shut-off valve 22 and the second oil cylinder 2; a third high-pressure flange 27 is provided at the connection between the third shut-off valve 23 and the third oil cylinder 3; and a fourth high-pressure flange 12 is provided at the connection between the fourth shut-off valve 24 and the fourth oil cylinder 4.

[0093] When in use: The piston-type steering gear operates with high oil pressure in the cylinder, and the reciprocating motion of the piston generates continuous pressure impact and mechanical vibration, which effectively avoids oil leakage and loosening of joints under high pressure, and ensures the sealing reliability of the four-cylinder oil circuit under long-term heavy load reciprocating load, which is suitable for the continuous operation requirements of ship steering gear.

[0094] The high-pressure flange, combined with the front-end shut-off valve, forms an independent oil circuit isolation unit: when a single cylinder fails, the cylinder seals are replaced, or the internal plunger structure is repaired, the corresponding shut-off valve can be closed first to cut off the oil circuit of that cylinder, and then the flange can be disassembled to separate the cylinder from the external pipeline. There is no need to drain the hydraulic oil from the entire tank, nor is it necessary to disassemble the entire set of external outfitting pipelines, which greatly shortens the maintenance time, reduces the maintenance workload and oil loss, and meets the convenience requirements of on-site operation and maintenance of ship equipment.

[0095] Example 4:

[0096] Example 4 is basically the same as Example 1, except that:

[0097] A first hydraulic assembly 17 is mounted on the side of the first oil tank 8. The first hydraulic assembly 17 is connected to a first control valve block 19 inside the first oil tank 8 via a first internal outfitting pipeline 10. A second hydraulic pump 18 is mounted on the side of the second oil tank 9. The second hydraulic pump 18 is connected to a second control valve block 20 inside the second oil tank 9 via a second internal outfitting pipeline 11. The first hydraulic assembly 17 also includes a first motor 171, which is connected to a first hydraulic pump 172. Valve block 19 further includes a first safety valve 193, which is disposed between the oil circuits of the first switching valve 192 and the first isolation valve 194; the control valve block 20 includes a second pilot valve 201, a second switching valve 202, and a second safety valve 203; the oil outlet of the second oil tank 9 is connected to the oil inlet of the second hydraulic pump 182 in the second hydraulic assembly 18, the oil outlet of the second hydraulic pump 182 is connected to the oil inlet of the second pilot valve 201, and the oil outlet of the second pilot valve 201 is connected to the oil outlet of the second hydraulic pump 182 in the second hydraulic assembly 18. The inlet of the switching valve 202 is connected, and the outlet of the second switching valve 202 is connected to the inlet of the first cylinder 1; the outlet of the second switching valve 202 is connected to the inlet of the second isolation valve 204, and the outlet of the second isolation valve 204 is connected to the inlet of the first isolation valve 194. The outlet of the first isolation valve 194 is connected to the inlet of the fourth cylinder 4 via port C, and the outlet of the second cylinder 2 is connected to the inlet of the second switching valve 202 via port B. The oil end is connected to the oil inlet of the second hydraulic pump 182, and the oil outlet of the second hydraulic pump 182 is connected to the oil inlet of the second oil tank 9; the oil outlet of the third cylinder 3 is connected to the oil inlet of the first isolation valve 194 via port D, the oil outlet of the first isolation valve 194 is connected to the oil inlet of the second isolation valve 204, and the oil outlet of the second isolation valve 204 is connected to the oil inlet of the second switching valve 202; the second safety valve 203 is located between the oil circuits of the second switching valve 202 and the second isolation valve 204.

[0098] In application: The first safety valve 193 and the second safety valve 203 are respectively installed between the switching valve and the isolation valve of the two pump stations. When the pipeline pressure exceeds the set threshold, the safety valve automatically overflows to relieve pressure and prevent high-pressure damage to the cylinder, pipeline and valve block. The high-pressure flange at the end of each cylinder is equipped with a shut-off valve, which can shut off the oil circuit of a single cylinder individually, which is convenient for maintenance and disassembly.

[0099] The above description is only a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. Any equivalent modifications or changes made by those skilled in the art based on the content disclosed in the present invention should be included within the scope of protection set forth in the claims.

Claims

1. A valve-controlled plunger-type steering gear suitable for inland waterway vessels, characterized in that: The valve-controlled plunger steering gear applicable to inland waterway vessels includes a first cylinder (1), a second cylinder (2), a third cylinder (3), a fourth cylinder (4), a first control valve block (19), and a second control valve block (20). The first cylinder (1) is connected to the second cylinder (2) through the first plunger assembly (5), the third cylinder (3) is connected to the fourth cylinder (4) through the second plunger assembly (6), the third cylinder (3) is connected to the first oil tank (8), and the fourth cylinder (4) is connected to the second oil tank (9); The first hydraulic assembly (17) is installed on the side of the first oil tank (8), and the first hydraulic assembly (17) is connected to the first control valve block (19). The second hydraulic pump (18) is installed on the side of the second oil tank (9), and the second hydraulic pump (18) is connected to the second control valve block (20). The first shut-off valve (21) on the first cylinder (1) is connected to the first control valve block (19), the third shut-off valve (23) on the third cylinder (3) is connected to the first control valve block (19), the second shut-off valve (22) on the second cylinder (2) is connected to the first control valve block (19), and the fourth shut-off valve (24) on the fourth cylinder (4) is connected to the first control valve block (19). The first control valve block (19) includes a first pilot valve (191), a first switching valve (192) and a first isolation valve (194), and the second control valve block (20) includes a second isolation valve (204). The oil outlet of the first oil tank (8) is connected to the oil inlet of the first hydraulic pump (172) in the first hydraulic assembly (17), the oil outlet of the first hydraulic pump (172) is connected to the oil inlet of the first pilot valve (191), the oil outlet of the first pilot valve (191) is connected to the oil inlet of the first switching valve (192), and the oil outlet of the first switching valve (192) is connected to the oil inlet of the second oil cylinder (2). The oil outlet of the first switching valve (192) is connected to the oil inlet of the first isolation valve (194), the oil outlet of the first isolation valve (194) is connected to the oil inlet of the second isolation valve (204), the oil outlet of the second isolation valve (204) is connected to the oil inlet of the third cylinder (3) via port D, the oil outlet of the first cylinder (1) is connected to the oil inlet of the first switching valve (192) via port A, the oil outlet of the first switching valve (192) is connected to the oil inlet of the first hydraulic pump (172), and the oil outlet of the first hydraulic pump (172) is connected to the oil inlet of the first oil tank (8). The oil outlet of the fourth oil cylinder (4) is connected to the oil inlet of the second isolation valve (204) via port C. The oil inlet of the second isolation valve (204) is connected to the oil inlet of the first isolation valve (194). The oil outlet of the first isolation valve (194) is connected to the oil inlet of the first switching valve (192).

2. The valve-controlled plunger steering gear for inland waterway vessels according to claim 1, characterized in that: The first cylinder (1) and the third cylinder (3) are connected by a first connecting seat (15), and the second cylinder (2) and the fourth cylinder (4) are connected by a second connecting seat (16).

3. A valve-controlled plunger-type steering gear suitable for inland waterway vessels according to claim 2, characterized in that: A rudder assembly (7) is provided between the first plunger assembly (5) and the second plunger assembly (6).

4. A valve-controlled plunger-type steering gear suitable for inland waterway vessels according to claim 3, characterized in that: The first hydraulic cylinder (1), the third hydraulic cylinder (3), the second hydraulic cylinder (2), the fourth hydraulic cylinder (4), and the rudder assembly (7) are arranged symmetrically around the center.

5. A valve-controlled plunger-type steering gear suitable for inland waterway vessels according to claim 2, characterized in that: A first guide rod (13) is installed between the first oil cylinder (1) and the second oil cylinder (2) above the first plunger assembly (5); A second guide rod (14) is installed between the third cylinder (3) and the fourth cylinder (4) below the second plunger assembly (6).

6. A valve-controlled plunger-type steering gear suitable for inland waterway vessels according to claim 5, characterized in that: A first high-pressure flange (25) is provided at the connection between the first shut-off valve (21) and the first oil cylinder (1), a second high-pressure flange (26) is provided at the connection between the second shut-off valve (22) and the second oil cylinder (2), a third high-pressure flange (27) is provided at the connection between the third shut-off valve (23) and the third oil cylinder (3), and a fourth high-pressure flange (28) is provided at the connection between the fourth shut-off valve (24) and the fourth oil cylinder (4).

7. A valve-controlled plunger-type steering gear suitable for inland waterway vessels according to claim 1, characterized in that: The first hydraulic assembly (17) is installed on the side of the first oil tank (8). The first hydraulic assembly (17) is connected to the first control valve block (19) inside the first oil tank (8) through the first internal outfitting pipeline (10). The second hydraulic pump (18) is installed on the side of the second oil tank (9). The second hydraulic pump (18) is connected to the second control valve block (20) inside the second oil tank (9) through the second internal outfitting pipeline (11).

8. A valve-controlled plunger-type steering gear suitable for inland waterway vessels according to claim 1, characterized in that: The first hydraulic assembly (17) also includes a first motor (171), which is connected to a first hydraulic pump (172).

9. A valve-controlled plunger-type steering gear suitable for inland waterway vessels according to claim 1, characterized in that: The first control valve block (19) also includes a first safety valve (193), which is located between the oil circuit of the first switching valve (192) and the first isolation valve (194).

10. A valve-controlled plunger-type steering gear suitable for inland waterway vessels according to claim 9, characterized in that: The control valve block (20) includes a second pilot valve (201), a second switching valve (202) and a second safety valve (203). The oil outlet of the second oil tank (9) is connected to the oil inlet of the second hydraulic pump (182) in the second hydraulic assembly (18). The oil outlet of the second hydraulic pump (182) is connected to the oil inlet of the second pilot valve (201). The oil outlet of the second pilot valve (201) is connected to the oil inlet of the second switching valve (202). The oil outlet of the second switching valve (202) is connected to the oil inlet of the first oil cylinder (1). The oil outlet of the second switching valve (202) is connected to the oil inlet of the second isolation valve (204), the oil outlet of the second isolation valve (204) is connected to the oil inlet of the first isolation valve (194), the oil outlet of the first isolation valve (194) is connected to the oil inlet of the fourth oil cylinder (4) via port C, the oil outlet of the second oil cylinder (2) is connected to the oil inlet of the second switching valve (202) via port B, the oil outlet of the second switching valve (202) is connected to the oil inlet of the second hydraulic pump (182), and the oil outlet of the second hydraulic pump (182) is connected to the oil inlet of the second oil tank (9). The oil outlet of the third cylinder (3) is connected to the oil inlet of the first isolation valve (194) via port D. The oil outlet of the first isolation valve (194) is connected to the oil inlet of the second isolation valve (204). The oil outlet of the second isolation valve (204) is connected to the oil inlet of the second switching valve (202). The second safety valve (203) is located between the oil circuit of the second switching valve (202) and the second isolation valve (204).

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