A luffing oil cylinder hydraulic control system for a lightering crane and its control method

Abstract

The present invention discloses a luffing oil cylinder hydraulic control system for a lighter crane and its control method, which relates to the technical field of the crane hydraulic control system. It includes a hydraulic oil output component that outputs the hydraulic oil in the fuel tank to the P port. The P port is connected to a first electromagnetic control valve and a second logic valve. The outlet end of the second logic valve is connected to a first control valve. The other connection port of the first control valve is connected to the small chamber of the oil cylinder, and the first control valve allows the hydraulic oil to flow forward or backward. The large chamber of the oil cylinder is connected to a first logic valve and a fourth electromagnetic control valve, and the other end of the first logic valve is connected back to the fuel tank. The outlet end of the second logic valve is also connected to a second electromagnetic control valve and a third logic valve, and the outlet end of the third logic valve is connected to the large chamber of the oil cylinder. The hydraulic oil enters the small chamber of the oil cylinder from the outlet of the second logic valve through the first control valve, or enters the large chamber of the oil cylinder through the third logic valve. Its structure is simple, achieving the effect of a compact layout of the luffing system.

Description

Technical Field

[0001] The present invention relates to the technical field of the hydraulic control system of a crane, and particularly relates to a luffing cylinder hydraulic control system of a lightering crane and a control method thereof. Background Art

[0002] Lightering cranes are widely used in the dock transfer system, and are responsible for the material handling conditions where, due to the small tonnage of the barge at small docks, it is necessary to transfer the materials of small boats to large ships, or transfer the materials of large ships to small boats.

[0003] Since it is installed and used on the hull deck surface, its installation space is relatively small, and various supporting components of the crane are required to save space as much as possible. Moreover, due to its operating environment, its system is required to be stable and reliable, and the control is simple and effective. Summary of the Invention

[0004] The purpose of the present invention is to provide a luffing cylinder hydraulic control system for a lightering crane, which has a simple structure, changes the control mode of the traditional open system that uses a three-position four-way directional control valve to realize the retraction and extension actions of the cylinder, and has a smaller space size compared with the traditional method, and has good popularization and usability for a compactly arranged luffing system.

[0005] The above technical purpose of the present invention is achieved through the following technical solutions:

[0006] A luffing cylinder hydraulic control system for a lightering crane includes a hydraulic oil output component. The hydraulic oil output component outputs the hydraulic oil in the fuel tank to the P port. The P port is connected to a first electromagnetic control valve and a second logic valve. The first electromagnetic control valve controls the opening and closing of the second logic valve. The outlet end of the second logic valve is connected to a first control valve. The other connection port of the first control valve is connected to the small chamber of the cylinder. The first control valve allows the hydraulic oil to flow forward or backward, entering or leaving the small chamber of the cylinder.

[0007] The large chamber of the cylinder is connected to a first logic valve and a fourth electromagnetic control valve. The fourth electromagnetic control valve controls the opening and closing of the first logic valve. The other end of the first logic valve is connected back to the fuel tank.

[0008] The outlet end of the second logic valve is also connected to a second electromagnetic control valve and a third logic valve. The second electromagnetic control valve controls the opening and closing of the third logic valve. The outlet end of the third logic valve is connected to the large chamber of the cylinder. The hydraulic oil enters the small chamber of the cylinder from the outlet of the second logic valve through the first control valve, or enters the large chamber of the cylinder through the third logic valve.

[0009] Furthermore, the outlet end of the first electromagnetic control valve is connected to the control port end of the second logic valve. The opening and closing of the first electromagnetic control valve control the on-off of the hydraulic oil therein, and complete the opening and closing control of the second logic valve.

[0010] Further, the control port end of the second logic valve is connected to an OR-gate shuttle valve, and the two inlet ends of the OR-gate shuttle valve are respectively connected to the outlet end of the first electromagnetic control valve and the outlet end of the second logic valve.

[0011] Further, the outlet end of the second electromagnetic control valve is connected to the control port end of the third logic valve. The opening and closing of the second electromagnetic control valve control the on-off of the hydraulic oil, thereby completing the opening and closing control of the third logic valve.

[0012] Further, the control port end of the third logic valve is connected to an OR-gate shuttle valve, and the two inlet ends of the OR-gate shuttle valve are respectively connected to the outlet end of the second electromagnetic control valve and the outlet end of the third logic valve.

[0013] Further, the first control valve includes a check valve chamber and a control chamber. The check valve chamber allows the hydraulic oil to enter the small chamber of the oil cylinder from the outlet end of the second logic valve. After the first control valve is energized, it switches to the control chamber, and the control chamber allows the hydraulic oil in the small chamber of the oil cylinder to leave.

[0014] Further, a second control valve is also provided between the large chamber of the oil cylinder and the first logic valve. One end of the second control valve is connected to the large chamber of the oil cylinder, and the other connection port is connected to the first logic valve. The second control valve allows the hydraulic oil to flow forward or backward to enter or leave the large chamber of the oil cylinder.

[0015] Further, it further includes a sixth solenoid valve. One end of the sixth solenoid valve is connected to the large chamber of the oil cylinder, and the other end is connected to the control end of the second control valve. After being energized, it injects the hydraulic oil into the control end of the second control valve to drive the second control valve to switch the valve chamber.

[0016] Further, the second control valve includes a check valve chamber and a control chamber. The check valve chamber allows the hydraulic oil to enter the large chamber of the oil cylinder from the outlet end of the third logic valve. After the sixth solenoid valve is energized, the hydraulic oil enters the control end of the second control valve from the large chamber of the oil cylinder, driving the second control valve to switch to the control chamber, and the control chamber allows the hydraulic oil in the large chamber of the oil cylinder to leave.

[0017] The present application also discloses a control method for the hydraulic control system of the luffing oil cylinder of a lightering crane, including the following steps.

[0018] When the luffing executes a descending action, the hydraulic oil output assembly outputs the hydraulic oil in the fuel tank to the P port. The first electromagnetic control valve is energized and commutated to control the one-way opening of the second logic valve. The hydraulic oil at the P port enters the first control valve through the second logic valve and then enters the small chamber of the oil cylinder to push the piston of the oil cylinder to retract. The fourth electromagnetic control valve is controlled to be energized and commutated to control the opening of the first logic valve, so that the hydraulic oil in the large chamber of the oil cylinder returns to the fuel tank through the first logic valve.

[0019] When the luffing mechanism performs the lifting action, the second logic valve remains open, the second solenoid control valve is energized and commutated to control the one-way opening of the third logic valve. The hydraulic oil at the P port enters the large chamber of the oil cylinder through the second logic valve and the third logic valve. The oil cylinder performs the extending action, and the hydraulic oil in the small chamber is pushed out. The first control valve is commutated to control the reverse flow of the hydraulic oil in the small chamber. Together with the oil coming from the P port in the second logic valve, it converges into the third logic valve and enters the large chamber of the oil cylinder, realizing the rapid extension of the oil cylinder.

[0020] In summary, the present invention has the following beneficial effects:

[0021] It changes the control method of the traditional open system that uses a three-position four-way directional control valve to realize the retraction and extension actions of the oil cylinder. The direction is switched by using a logic unit. At the same time, under the luffing working condition, the self-weight of the load itself is utilized to control the lowering of the oil cylinder. A simple combination of small solenoid valves is adopted during the switching of the boom lifting and lowering, realizing the action switching of the actuator.

[0022] The control method of the hydraulic system of the oil cylinder of this lighter crane has a simple structure and relatively small space dimensions compared with the traditional method, and has good promotion and usability for the compact luffing system; since the components constituting the entire control system are relatively simple, the system control value is more concise and effective than the traditional method, so the market promotion is good. Description of the Drawings

[0023] Figure 1 is the overall structural schematic diagram of a hydraulic control system for the luffing oil cylinder of a lighter crane according to the present invention;

[0024] Figure 2 is Figure 1 the structural schematic diagram of the hydraulic control part in

[0025] Figure 3 is the hydraulic schematic diagram of a hydraulic control system for the luffing oil cylinder of a lighter crane when the luffing mechanism performs the lowering action according to the present invention;

[0026] Figure 4 is the control schematic diagram of a hydraulic control system for the luffing oil cylinder of a lighter crane when the luffing mechanism performs the lowering action according to the present invention;

[0027] Figure 5 is the hydraulic schematic diagram of a hydraulic control system for the luffing oil cylinder of a lighter crane when the luffing mechanism performs the lifting action according to the present invention;

[0028] Figure 6 is the control schematic diagram of a hydraulic control system for the luffing oil cylinder of a lighter crane when the luffing mechanism performs the lifting action according to the present invention. Detailed Embodiment

[0029] The following further describes the specific embodiments of the present invention in conjunction with the accompanying drawings. This embodiment does not constitute a limitation on the present invention. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of this application.

[0030] A luffing cylinder hydraulic control system for a lighter crane, as Figure 1 shown, includes a hydraulic oil output component. The hydraulic oil output component outputs the hydraulic oil in the fuel tank to the P port. In this embodiment, the hydraulic oil output component includes multiple pump components YB01, YB02, YB03, and YB04, which are connected in the fuel tank and are energized to output hydraulic oil to the P port (P1 and P2 ports).

[0031] As Figure 2 shown, the P port is connected to the first electromagnetic control valve BV01 and the second logic valve LJ02. The first electromagnetic control valve BV01 controls the opening and closing of the second logic valve LJ02. The outlet end of the second logic valve LJ02 is connected to the first control valve BL01. The other connection port of the first control valve BL01 is connected to the small chamber of the cylinder. The first control valve BL01 allows the hydraulic oil to flow forward or backward, entering or leaving the small chamber of the cylinder;

[0032] Among them, the outlet end of the first electromagnetic control valve BV01 is connected to the control port end of the second logic valve LJ02. The opening and closing of the first electromagnetic control valve BV01 control the on-off of the hydraulic oil therein, completing the opening and closing control of the second logic valve LJ02;

[0033] The control port end of the second logic valve LJ02 is connected to an OR-type shuttle valve. The two inlet ends of the OR-type shuttle valve are respectively connected to the outlet end of the first electromagnetic control valve BV01 and the outlet end of the second logic valve LJ02, so that the second logic valve LJ02 can only be opened unidirectionally;

[0034] The first control valve BL01 includes a check valve chamber and a control chamber. The check valve chamber allows the hydraulic oil to enter the small chamber of the cylinder from the outlet end of the second logic valve LJ02. After the first control valve BL01 is energized, it switches to the control chamber, and the control chamber allows the hydraulic oil in the small chamber of the cylinder to leave;

[0035] In this embodiment, the large chamber of the cylinder is also connected to the third electromagnetic control valve BV03. The other end of the third electromagnetic control valve BV03 is connected to the hydraulic control end of the first control valve BL01. After the third electromagnetic control valve BV03 is energized and opened, hydraulic oil is introduced to drive the first control valve BL01 to switch to the control chamber.

[0036] As Figure 2As shown in the figure, the large chamber of the oil cylinder is connected to the sixth solenoid valve YB06 and the second control valve BL02. One end of the sixth solenoid valve YB06 is connected to the large chamber of the oil cylinder, and the other end is connected to the control end of the second control valve BL02. When powered on, hydraulic oil is introduced into the control end of the second control valve BL02 to drive the second control valve BL02 to switch the valve chamber.

[0037] Another connection port of the second control valve BL02 is connected to the first logic valve LJ01 and the fourth solenoid control valve BV04. The fourth solenoid control valve BV04 controls the opening and closing of the first logic valve LJ01, and the other end of the first logic valve LJ01 is connected back to the fuel tank.

[0038] So that one end of the second control valve BL02 is connected to the large chamber of the oil cylinder, and the other connection port is connected to the first logic valve LJ01, allowing hydraulic oil to flow forward or backward, entering or leaving the large chamber of the oil cylinder.

[0039] Among them, the second control valve BL02 includes a check valve chamber and a control chamber. The check valve chamber allows hydraulic oil to enter the large chamber of the oil cylinder from the outlet end of the third logic valve LJ03. After the sixth solenoid valve YB06 is powered on, the hydraulic oil enters the control end of the second control valve BL02 from the large chamber of the oil cylinder, driving the second control valve BL02 to switch to the control chamber, and the control chamber allows the hydraulic oil in the large chamber of the oil cylinder to leave.

[0040] As Figure 2 shown, the outlet end of the second logic valve LJ02 is also connected to the second solenoid control valve BL02 and the third logic valve LJ03. The second solenoid control valve BL02 controls the opening and closing of the third logic valve LJ03, and the outlet end of the third logic valve LJ03 is connected to the large chamber of the oil cylinder. Hydraulic oil enters the small chamber of the oil cylinder from the outlet of the second logic valve LJ02 through the first control valve BL01, or enters the large chamber of the oil cylinder through the third logic valve LJ03.

[0041] The outlet end of the second solenoid control valve BL02 is connected to the control port end of the third logic valve LJ03. The opening and closing of the second solenoid control valve BL02 control the on-off of the hydraulic oil therein, completing the opening and closing control of the third logic valve LJ03.

[0042] The control port end of the third logic valve LJ03 is connected to an OR-gate shuttle valve. The two inlet ends of the OR-gate shuttle valve are respectively connected to the outlet end of the second solenoid control valve BL02 and the outlet end of the third logic valve LJ03, so that the third logic valve LJ03 can only be opened unidirectionally.

[0043] This application also discloses a control method for the hydraulic control system of the luffing oil cylinder of a lightering crane, including the following steps.

[0044] As Figure 3 and Figure 4As shown, when the amplitude change is performed to descend, the handle starts to operate, the electric control signal enters the PLC, and the PLC gives a signal to control the hydraulic oil output components YB01, YB02, YB03, and YB04 to output hydraulic oil electrically, and output the hydraulic oil in the oil tank to the P1 and P2 ports;

[0045] like Figure 3 In the direction of the black bold oil circuit, the first electromagnetic control valve BV01 is energized to switch direction, disconnecting the hydraulic oil circuit, so that the second logic valve LJ02 is opened in one direction, and the hydraulic oil at the P1 and P2 ports enters the one-way valve chamber of the first control valve BL01 through the second logic valve LJ02, and then flows into the small chamber of the oil cylinder, pushing the oil cylinder piston back;

[0046] like Figure 3 The direction of the blue bold oil circuit part in the middle, the sixth solenoid valve YB06 and the whole machine operating handle are jointly controlled. When the handle executes the descending command, the sixth solenoid valve YB06 starts to load the current to conduct, and the control oil circuit passes through the second control valve BL02 and enters the control end of the second control valve BL02, driving the second control valve BL02 to switch to the control chamber, and the hydraulic oil in the large chamber of the oil supply cylinder in the control chamber enters the first logic valve LJ01 from the second control valve BL02, and the fourth solenoid control valve BV04 is energized to control the first logic valve LJ01 to conduct, allowing the hydraulic oil to flow back to the oil tank.

[0047] like Figure 5 and Figure 6 As shown, when the amplitude change is performed to rise, the handle starts to operate, the electric control signal enters the PLC, and the PLC gives a signal to control the hydraulic oil output components YB01, YB02, YB03, and YB04 to output hydraulic oil electrically, and output the hydraulic oil in the oil tank to the P1 and P2 ports;

[0048] like Figure 5 In the direction of the black bold oil circuit, the second logic valve LJ02 remains open, the second solenoid control valve BL02 is energized to change direction, and the third logic valve LJ03 is controlled to be one-way open. The sixth solenoid valve YB06 is de-energized and disconnected, and the second control valve BL02 is reset to the one-way valve chamber. The hydraulic oil supplied to the P port passes through the second logic valve LJ02, the third logic valve LJ03, and the second control valve BL02 in sequence into the large chamber of the oil cylinder. The oil cylinder performs the extension action, and the hydraulic oil in the small chamber is pushed out.

[0049] The first control valve BL01 is switched (after the third solenoid control valve BV03 is energized and opened, the hydraulic oil in the large chamber of the cylinder is introduced and the first control valve BL01 is driven to switch to the control chamber), controlling the hydraulic oil in the small chamber to flow out in the opposite direction, and together with the oil from the P port in the second logic valve LJ02, it is merged into the third logic valve LJ03 and enters the large chamber of the cylinder, realizing the rapid ejection of the cylinder.

[0050] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. Those skilled in the art can make various modifications or equivalent replacements to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent replacements should also be regarded as falling within the protection scope of the technical solution of the present invention.

Claims

1. A luffing oil cylinder hydraulic control system for a lightering crane, characterized in that: It includes a hydraulic oil output component which outputs the hydraulic oil in the fuel tank to port P. Port P is connected to a first electromagnetic control valve and a second logic valve. The first electromagnetic control valve controls the opening and closing of the second logic valve. The outlet end of the second logic valve is connected to a first control valve. The other connection port of the first control valve is connected to the small chamber of the oil cylinder. The first control valve allows the hydraulic oil to flow forward or backward, entering or leaving the small chamber of the oil cylinder. The large chamber of the oil cylinder is connected to a third electromagnetic control valve, a sixth solenoid valve, a first logic valve and a fourth electromagnetic control valve. The other end of the third electromagnetic control valve is connected to the hydraulic control end of the first control valve. The fourth electromagnetic control valve controls the opening and closing of the first logic valve. The other end of the first logic valve is connected back to the fuel tank. A second control valve is also provided between the large chamber of the oil cylinder and the first logic valve. One end of the second control valve is connected to the large chamber of the oil cylinder, and the other connection port is connected to the first logic valve. The second control valve allows the hydraulic oil to flow forward or backward, entering or leaving the large chamber of the oil cylinder. One end of the sixth solenoid valve is connected to the large chamber of the oil cylinder, and the other end is connected to the control end of the second control valve. After being energized, it passes the hydraulic oil into the control end of the second control valve to drive the second control valve to switch the valve cavity. The second control valve includes a check valve cavity and a control cavity. The check valve cavity allows the hydraulic oil to enter the large chamber of the oil cylinder from the outlet end of the third logic valve. After the sixth solenoid valve is energized, the hydraulic oil enters the control end of the second control valve from the large chamber of the oil cylinder, driving the second control valve to switch to the control cavity. The control cavity allows the hydraulic oil in the large chamber of the oil cylinder to leave. The outlet end of the second logic valve is also connected to a second electromagnetic control valve and a third logic valve. The second electromagnetic control valve controls the opening and closing of the third logic valve. The outlet end of the third logic valve is connected to the large chamber of the oil cylinder. The hydraulic oil enters the small chamber of the oil cylinder from the outlet of the second logic valve through the first control valve, or enters the large chamber of the oil cylinder through the third logic valve.

2. The hydraulic control system for the luffing cylinder of a lightering crane according to claim 1, wherein: The outlet end of the first electromagnetic control valve is connected to the control port end of the second logic valve. The opening and closing of the first electromagnetic control valve control the on-off of the hydraulic oil therein to complete the opening and closing control of the second logic valve.

3. The hydraulic control system for the luffing cylinder of a lighterage crane according to claim 2, characterized in that: The control port end of the second logic valve is connected to an OR-type shuttle valve. The two inlet ends of the OR-type shuttle valve are respectively connected to the outlet end of the first electromagnetic control valve and the outlet end of the second logic valve.

4. A luffing cylinder hydraulic control system for a lighter crane according to claim 1 or 2, characterized in that: The outlet end of the second electromagnetic control valve is connected to the control port end of the third logic valve. The opening and closing of the second electromagnetic control valve control the on-off of the hydraulic oil therein to complete the opening and closing control of the third logic valve.

5. A luffing cylinder hydraulic control system for a lightering crane according to claim 4, characterized in that: The control port end of the third logic valve is connected to an OR-type shuttle valve. The two inlet ends of the OR-type shuttle valve are respectively connected to the outlet end of the second electromagnetic control valve and the outlet end of the third logic valve.

6. The hydraulic control system for the luffing oil cylinder of a lighterage crane according to claim 1, characterized in that: The first control valve includes a check valve cavity and a control cavity. The check valve cavity allows the hydraulic oil to enter the small chamber of the oil cylinder from the outlet end of the second logic valve. After the first control valve is energized, it switches to the control cavity. The control cavity allows the hydraulic oil in the small chamber of the oil cylinder to leave.

7. A control method for the luffing cylinder hydraulic control system of a lighterage crane as described in claim 1, characterized in that: It includes the following steps When the luffing mechanism performs the lowering action, the hydraulic oil output component outputs the hydraulic oil in the fuel tank to port P. The first electromagnetic control valve is energized and commutated to control the one-way opening of the second logic valve. The hydraulic oil at port P enters the first control valve through the second logic valve and then enters the small chamber of the oil cylinder, pushing the piston of the oil cylinder to retract. The fourth electromagnetic control valve is energized and commutated to control the opening of the first logic valve, allowing the hydraulic oil in the large chamber of the oil cylinder to return to the fuel tank through the first logic valve. When the luffing mechanism performs the raising action, the second logic valve remains open. The second electromagnetic control valve is energized and commutated to control the one-way opening of the third logic valve. The hydraulic oil at port P enters the large chamber of the oil cylinder through the second logic valve and the third logic valve. The oil cylinder performs the extending action, and the hydraulic oil in the small chamber of the oil cylinder is pushed out. The first control valve is commutated to control the reverse flow of the hydraulic oil in the small chamber of the oil cylinder, which together with the oil coming from port P in the second logic valve, converges into the third logic valve and enters the large chamber of the oil cylinder to achieve the rapid extension of the oil cylinder.

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