Multi-cylinder synchronous hydraulic jacking system of tower crane

Abstract

The utility model discloses a tower crane multi-cylinder synchronous hydraulic jacking system which is composed of a plurality of pump stations and a main oil cylinder, each pump station is composed of a variable frequency motor and a main oil pump, the power input end of each main oil pump is connected with the corresponding variable frequency motor, the oil outlet end of each main oil pump is connected with a first one-way valve, and the rear portion of each first one-way valve is divided into four oil ways. The first branch is connected with a first overflow valve and used for limiting system pressure, the second branch is connected with a first pressure gauge and used for displaying the system pressure, and the third branch is connected with a stop valve and used for being connected with a public node for emergency use. In the jacking process, speed adjustment is continuous, stable and impact-free, opening and closing of the balance valve are not caused in the adjusting process, shaking and abnormal sound are avoided, if a certain oil pump or motor in the system breaks down, the power input can be closed, then all the stop valves are opened, oil ways are communicated, automatic or manual operation is utilized, and the working efficiency is greatly improved. The return or jacking process of the oil cylinder is achieved, and the safety and reliability of the system are greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic jacking, in particular to a multi-cylinder synchronous hydraulic jacking system of a tower crane. Background Art

[0002] With economic development, the number of large tower cranes is increasing. The lifting capacity of single-cylinder jacking systems is increasingly unable to meet market demand. Currently, most multi-cylinder jacking systems (two-cylinder and four-cylinder) still use a manual synchronization method, which is unreliable and prone to accidents. Intelligent synchronous jacking systems are subject to under-adjustment, over-adjustment, and frequent adjustments, causing a straight-line ascent to take on an S-shaped form after frequent adjustments. Furthermore, abnormal noises and pressure shocks can occur during the adjustment process. This intelligent hydraulic synchronous jacking system has been developed to improve the safety of large tower cranes during jacking and dismantling operations. Utility Model Content

[0003] In order to solve the problem that most of the existing multi-cylinder jacking systems still use a manual synchronization method with low reliability and prone to accidents, the utility model provides a multi-cylinder synchronous hydraulic jacking system for a tower crane.

[0004] To achieve the above objectives, the present invention provides the following technical solutions:

[0005] A multi-cylinder synchronous hydraulic jacking system for a tower crane consists of multiple pump stations and a main oil cylinder, and the pump station consists of a variable frequency motor and a main oil pump, the power input end of the main oil pump is connected to the variable frequency motor, and the oil outlet end is connected to a first one-way valve, which is divided into four branch oil circuits after the first one-way valve, branch one is connected to a first overflow valve for limiting system pressure, branch two is connected to a first pressure gauge for displaying system pressure, branch three is connected to a stop valve for connecting to a public node for emergency use, branch four is connected to the P port of the electromagnetic manual reversing valve, the A port of the electromagnetic manual reversing valve is connected to the large chamber of the main oil cylinder through a balancing valve, the B port of the electromagnetic manual reversing valve is connected to the small chamber of the main oil cylinder through a second one-way valve, and overflow valves are connected to both ends of the second one-way valve; a displacement sensor is connected to the main oil cylinder for real-time monitoring of the displacement difference of the main oil cylinder.

[0006] Preferably, the pump station is provided with an oil suction filter, an oil return filter and an air filter for filtering impurities in the hydraulic oil.

[0007] Preferably, the master cylinder is connected to a safety valve to prevent cylinder expansion, and is also connected to a pressure sensor for real-time monitoring of the pressure of the master cylinder.

[0008] Preferably, the pump station is also connected to a thermal management system, which is composed of a heat exchange pump, a first motor, a second pressure gauge, a fourth overflow valve and a heat exchanger connected in sequence to ensure the temperature of the hydraulic oil.

[0009] Preferably, it also includes an auxiliary oil cylinder system connected to the pump station, which is composed of an auxiliary pump, a second motor, a fifth overflow valve, a third pressure gauge, a reversing valve, a one-way throttle valve and an auxiliary oil cylinder connected in sequence.

[0010] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention improves the initial zeroing operation to uniformly pre-press multiple master oil cylinders, ensuring that the initial load is basically consistent. The lifting process has a safe operating curve of soft start, high-speed operation, and soft positioning. Through feedback from the displacement sensor, the PLC controller continuously fine-tunes the oil intake of the oil cylinder after calculation. The multiple cylinders are precisely and synchronously lifted, and the synchronization error is less than 5mm. The speed adjustment during the lifting process is continuous, stable, and impact-free. The adjustment process will not cause the balance valve to open and close, and there is no jitter or abnormal noise. In addition, if a certain oil pump or motor in the system fails, the power input of this line can be turned off, and then all the stop valves can be opened to realize the common oil circuit. The oil cylinder can be returned to its original position or lifted by automatic or manual operation, greatly improving the safety and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the principle of using two-cylinder synchronous hydraulic jacking in Example 1 of the present utility model;

[0012] Figure 2 This is a schematic diagram of the principle of four-cylinder synchronous hydraulic jacking in Example 2 of the present utility model.

[0013] In the figure: 1. Oil suction filter, 2. Frequency conversion motor, 3. Main oil pump, 4. First one-way valve, 5. First relief valve, 6. Stop valve, 7. Solenoid manual reversing valve, 8. Second relief valve, 9. Second one-way valve, 10. Pressure sensor, 11. Displacement sensor, 12. Balancing valve, 13. Main oil cylinder, 14. Third relief valve, 15. First pressure gauge, 16. Return oil filter, 17. Air filter, 18. Heat exchanger pump, 19. First motor, 20. Second pressure gauge, 21. Fourth relief valve, 22. Heat exchanger, 23. Auxiliary pump, 24. Second motor, 25. Fifth relief valve, 26. Third pressure gauge, 27. Reversing valve, 28. One-way throttle valve, 29. Auxiliary oil cylinder. DETAILED DESCRIPTION

[0014] In the description of the present invention, it should be understood that the terms "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside", "vertical", "horizontal", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0015] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Example

[0016] like Figure 1 As shown, the synchronous hydraulic jacking system consists of two pumping stations and a main oil cylinder 13, and the pumping station consists of a variable frequency motor 2 and a main oil pump 3. The power input end of the main oil pump 3 is connected to the variable frequency motor 2, and the oil outlet end is connected to a first one-way valve 4. The first one-way valve 4 is divided into four branch oil circuits. Branch one is connected to a first overflow valve 5 for limiting the system pressure, branch two is connected to a first pressure gauge 15 for displaying the system pressure, branch three is connected to a stop valve 6 for connecting to a public node for emergency use, branch four is connected to the P port of the electromagnetic manual reversing valve 7, and the A port of the electromagnetic manual reversing valve 7 is connected to the large chamber of the main oil cylinder 13 through a balancing valve 12. The B port of the electromagnetic manual reversing valve 7 is connected to the small chamber of the main oil cylinder 13 through a second one-way valve 9, and overflow valves are connected to both ends of the second one-way valve 9; a displacement sensor 11 is connected to the main oil cylinder 13 for real-time monitoring of the displacement difference of the main oil cylinder 13.

[0017] The hydraulic components in the present invention are all connected to the PLC controller, which is connected to a touch screen and other electronic control components. When the multi-cylinder synchronous hydraulic jacking system is working normally, the shut-off valves 6 of all branch systems are shut off to ensure that each branch system is not connected to each other and operates independently. Input the cylinder diameter, rod diameter, rated pressure of the main oil cylinder 13, the displacement of the main oil pump 3, the rated speed of the frequency conversion motor 2 and other parameters on the touch screen, and the system will be initialized. After the initialization calculation, the maximum jacking speed, minimum jacking speed and other parameter values will be displayed on the touch screen. The operator enters the specific value of the jacking number. After calculation, the system stores the frequency value and writes it on the touch screen, and drives the frequency converter to work. During operation, the displacement signal of the extension or retraction of the main oil cylinder 13 and its difference will be calculated in real time. If it exceeds the warning range setting value, the PLC controller will reset the frequency converter parameters after calculation and adjust the speed of each main oil cylinder 13, thereby achieving synchronous control and speed control. To reduce the number of PLC controller adjustments, the touch screen displays the displacement difference and manual fine-tuning boxes for each variable frequency motor 2 input frequency. The operator can manually fine-tune the variable frequency motor 2 frequency based on the observed trend of these different values, effectively reducing the number of PLC controller adjustments and improving system stability. If a pump or motor in the system fails, the power input of that channel can be shut off and all shutoff valves can be opened to achieve a common oil circuit. The cylinder can then be automatically or manually operated to return or raise the cylinder, greatly improving the safety and reliability of the system. Example

[0018] like Figure 2 As shown, the synchronous hydraulic jacking system consists of four pump stations and a main oil cylinder 13.

[0019] Preferably, an oil suction filter 1, an oil return filter 16 and an air filter 17 are provided in the pump station for filtering impurities in the hydraulic oil.

[0020] Preferably, the master cylinder 13 is connected to a safety valve to prevent cylinder expansion, and is also connected to a pressure sensor 10 for monitoring the pressure of the master cylinder 13 in real time.

[0021] Preferably, the pump station is also connected to a thermal management system, which is composed of a heat exchange pump 18, a first motor 19, a second pressure gauge 20, a fourth overflow valve 21 and a heat exchanger 22 connected in sequence to ensure the temperature of the hydraulic oil.

[0022] Preferably, an auxiliary oil cylinder system connected to the pump station is also included. The auxiliary oil cylinder system is composed of an auxiliary pump 23, a second motor 24, a fifth overflow valve 25, a third pressure gauge 26, a reversing valve 27, a one-way throttle valve 28 and an auxiliary oil cylinder 29 connected in sequence to further improve safety.

[0023] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-cylinder synchronous hydraulic jacking system for a tower crane, characterized by: It is composed of multiple pump stations and main oil cylinders, and the pump station is composed of a variable frequency motor and a main oil pump. The power input end of the main oil pump is connected to the variable frequency motor, and the oil outlet end is connected to a first one-way valve. The first one-way valve is divided into four oil branches. Branch one is connected to a first overflow valve for limiting the system pressure, branch two is connected to a first pressure gauge for displaying the system pressure, branch three is connected to a stop valve for connecting to a public node for emergency use, branch four is connected to the P port of the electromagnetic manual reversing valve, and the A port of the electromagnetic manual reversing valve is connected to the large cavity of the main oil cylinder through a balancing valve, and the B port of the electromagnetic manual reversing valve is connected to the small cavity of the main oil cylinder through a second one-way valve, and overflow valves are connected to both ends of the second one-way valve; a displacement sensor is connected to the main oil cylinder for real-time monitoring of the displacement difference of the main oil cylinder.

2. The multi-cylinder synchronous hydraulic jacking system for a tower crane according to claim 1, characterized in that: The pump station is provided with an oil suction filter, an oil return filter and an air filter for filtering impurities in the hydraulic oil.

3. The multi-cylinder synchronous hydraulic jacking system for a tower crane according to claim 1, characterized in that: The master oil cylinder is connected to a safety valve to prevent the cylinder from expanding, and is also connected to a pressure sensor for real-time monitoring of the pressure of the master oil cylinder.

4. The multi-cylinder synchronous hydraulic jacking system for a tower crane according to claim 1, characterized in that: The pump station is also connected to a thermal management system, which is composed of a heat exchange pump, a first motor, a second pressure gauge, a fourth overflow valve and a heat exchanger connected in sequence to ensure the temperature of the hydraulic oil.

5. The multi-cylinder synchronous hydraulic jacking system for a tower crane according to claim 1, characterized in that: It also includes an auxiliary oil cylinder system connected to the pump station, which is composed of an auxiliary pump, a second motor, a fifth overflow valve, a third pressure gauge, a reversing valve, a one-way throttle valve and an auxiliary oil cylinder connected in sequence.

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