Closed-loop electro-hydraulic control system of unbalance-load-resistant wide-table hydraulic machine

Abstract

The invention discloses a closed-loop electro-hydraulic control system of an unbalance-load-resistant wide-table-board hydraulic machine, which comprises a group of power systems, two safety protection systems and a pair of piston oil cylinders connected with a sliding block of a press machine, and further comprises a closed-loop electro-hydraulic control system and a pair of magnetic grids. The device is used in cooperation with a sliding block with a press machine, the two piston oil cylinders are installed at the two ends of the sliding block correspondingly, when the press machine is in an unbalance loading state, the left end and the right end of the sliding block are not located on the same horizontal plane, and magnetic grids of the displacement monitoring devices at the left end and the right end of the sliding block send monitored data to a PLC; data monitored by the left magnetic grid and the right magnetic grid are compared through a PLC program to generate control output, the control output is output to the closed-loop electro-hydraulic control system through the A / D conversion module, the closed-loop electro-hydraulic control system controls the pressure of rod cavities of the two piston oil cylinders, closed-loop control is achieved, the operation precision of the sliding block in the pressing process is guaranteed, and therefore the good unbalance loading resisting effect is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical and hydraulic control systems, and more specifically to a closed-loop electro-hydraulic control system for an anti-eccentric load wide-table hydraulic press. Background Art

[0002] In multi-station production and processing, presses often have serious problems with off-center loading, so some anti-off-center loading mechanisms are needed. Traditional anti-off-center loading structures are generally mechanical parallel mechanisms, which can only meet the needs of workplaces with smaller off-center loading, and the forming accuracy of hydraulic presses with this structure is low. With the continuous improvement of the forming quality requirements for automotive cover parts, the original mechanical parallel mechanisms can no longer meet the processing needs.

[0003] Therefore, we proposed a closed-loop electro-hydraulic control system for a wide-table hydraulic press that is resistant to off-center loads to solve the above problems. Summary of the invention

[0004] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load function, so as to solve the problems raised in the above-mentioned background technology.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: a closed-loop electro-hydraulic control system for a wide-table hydraulic press that resists off-center loading, comprising a power system, two safety protection systems and a pair of piston cylinders connected to a press slide, the control system also comprising a closed-loop electro-hydraulic control system and a pair of magnetic grids; a pair of the piston cylinders are respectively connected to a safety protection system, and a pair of the magnetic grids are respectively arranged on the left and right sides of the press slide; the two safety protection systems are respectively connected to the closed-loop electro-hydraulic control system through an oil circuit; the closed-loop electro-hydraulic control system is connected to the power system through an oil circuit.

[0006] The present invention is used in conjunction with a press slider, and two piston cylinders are respectively installed at both ends of the slider. When the press is in an off-center load state, the left and right sides of the slider are not in the same horizontal plane. The magnetic grids of the displacement monitoring devices at the left and right ends of the slider send the monitored data to the PLC. The PLC program compares the data monitored by the left and right magnetic grids to generate a control output, which is then output to a closed-loop electro-hydraulic control system through an A / D conversion module. The closed-loop electro-hydraulic control system controls the pressure of the rod chambers of the two piston cylinders to achieve closed-loop control, thereby ensuring the operating accuracy of the slider during the pressing process, thereby achieving a good anti-off-center load effect.

[0007] In a preferred embodiment, the safety protection system includes a two-position three-way solenoid valve, a first directional valve, a speed regulating valve and an oil return tank; The outlet end of the two-position three-way solenoid valve is connected to the inlet end of the first directional valve of the two safety protection systems through an oil circuit; The outlet end of the first directional valve is connected to the rod chamber of the piston cylinder through an oil circuit.

[0008] In a preferred embodiment, the speed regulating valve is connected to an oil circuit, and the oil circuit is an oil circuit connecting the piston cylinder and the first directional valve; The outlet end of the speed regulating valve is connected to the oil return tank through a pipeline.

[0009] In a preferred embodiment, the closed-loop electro-hydraulic control system includes a two-position two-way solenoid valve, a three-position four-way solenoid valve, and a second directional valve; The second directional valve of the closed-loop electro-hydraulic control system is connected to the power system, and the inlet end of the two-position two-way solenoid valve is connected to the second directional valve through an oil circuit.

[0010] In a preferred embodiment, the three-position four-way solenoid valve is connected in parallel with the two-position two-way solenoid valve.

[0011] In a preferred embodiment, an electric control signal device is provided between the two-position two-way solenoid valve and the three-position four-way solenoid valve.

[0012] In a preferred embodiment, the electric control signal device is connected to the two-position two-way solenoid valve and the three-position four-way solenoid valve respectively.

[0013] In a preferred embodiment, the closed-loop electro-hydraulic control system is connected to the safety protection system through a plurality of oil circuits, and a one-way valve is respectively arranged on the oil circuits.

[0014] In a preferred embodiment, the closed-loop electro-hydraulic control opens a branch oil circuit connected to the power system, and the branch oil circuit is connected to the rodless chamber of the piston cylinder.

[0015] Technical effects and advantages of the present invention: The present invention is used in conjunction with a press slider, and two piston cylinders are respectively installed at both ends of the slider. When the press is in an off-center load state, the left and right sides of the slider are not in the same horizontal plane. The magnetic grids of the displacement monitoring devices at the left and right ends of the slider send the monitored data to the PLC. The PLC program compares the data monitored by the left and right magnetic grids to generate a control output, which is then output to a closed-loop electro-hydraulic control system through an A / D conversion module. The closed-loop electro-hydraulic control system controls the pressure of the rod chambers of the two piston cylinders to achieve closed-loop control, thereby ensuring the operating accuracy of the slider during the pressing process, thereby achieving a good anti-off-center load effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the control system of the present invention. Implementation

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Reference Figure 1 , a closed-loop electro-hydraulic control system for an anti-eccentric load wide-table hydraulic press, including a power system, two safety protection systems and a pair of piston cylinders connected to the slide of the press, and the control system also includes a closed-loop electro-hydraulic control system and a pair of magnetic grids; A pair of piston cylinders are respectively connected with safety protection systems, a pair of magnetic grids are respectively arranged on the left and right sides of the press slide, and the safety protection system includes a two-position three-way solenoid valve, a first directional valve, a speed regulating valve and an oil return groove; the outlet end of the two-position three-way solenoid valve is connected to the inlet end of the first directional valve of the two safety protection systems through an oil circuit; the outlet end of the first directional valve is connected to the rod chamber of the piston cylinder through an oil circuit.

[0019] The speed regulating valve is connected to an oil circuit, and the oil circuit is an oil circuit connecting the piston cylinder and the first directional valve; the outlet end of the speed regulating valve is connected to the oil return tank through a pipeline.

[0020] The safety protection system uses a two-position three-way solenoid valve, a first directional valve and a speed regulating valve to regulate the cylinder pressure when the piston cylinder is subjected to a heavy eccentric load, thus ensuring safe and stable operation. The closed-loop electro-hydraulic control system includes a two-position two-way solenoid valve, a three-position four-way solenoid valve, and a second directional valve; the second directional valve of the closed-loop electro-hydraulic control system is connected to the power system, the inlet end of the two-position two-way solenoid valve is connected to the second directional valve through an oil circuit, and the two safety protection systems are respectively connected to the closed-loop electro-hydraulic control system through oil circuits; the closed-loop electro-hydraulic control system is connected to the power system through the oil circuit, and the closed-loop electro-hydraulic control opens a branch oil circuit connected to the power system, and the branch oil circuit is connected to the rodless chamber of the piston cylinder.

[0021] The data monitored by the magnetic grating of the displacement monitoring device of the present invention is transmitted to the electric control signal device after being formed into an electrical signal through the PIC program module and the A / D conversion module. The electric control signal device transmits the voltage value to the two-position two-way solenoid valve and the three-position four-way solenoid valve. The two valves receive different voltage values ​​respectively, and control the two piston cylinders to act respectively through different working states, thereby achieving the purpose of resisting unbalanced load.

[0022] The three-position four-way solenoid valve is connected in parallel with the two-position two-way solenoid valve, an electric control signal device is provided between the two-position two-way solenoid valve and the three-position four-way solenoid valve, the electric control signal device is respectively connected to the two-position two-way solenoid valve and the three-position four-way solenoid valve, the closed-loop electro-hydraulic control system is connected to the safety protection system through multiple oil circuits, and a one-way valve is respectively provided on the oil circuits.

[0023] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load, comprising a power system, two safety protection systems and a pair of piston cylinders connected to a press slide, characterized in that; The control system also includes a closed-loop electro-hydraulic control system and a pair of magnetic grids; A pair of piston cylinders are respectively connected to a safety protection system, and a pair of magnetic grids are respectively arranged on the left and right sides of the press slide; The two safety protection systems are connected to the closed-loop electro-hydraulic control system through oil circuits respectively; The closed-loop electro-hydraulic control system is connected to the power system via an oil circuit.

2. The closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load as claimed in claim 1 is characterized by: The safety protection system includes a two-position three-way solenoid valve, a first directional valve, a speed regulating valve and an oil return tank; The outlet end of the two-position three-way solenoid valve is connected to the inlet end of the first directional valve of the two safety protection systems through an oil circuit; The outlet end of the first directional valve is connected to the rod chamber of the piston cylinder through an oil circuit.

3. The closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load as claimed in claim 2 is characterized by: The speed regulating valve is connected to the oil circuit, and the oil circuit is the oil circuit connecting the piston cylinder and the first directional valve; The outlet end of the speed regulating valve is connected to the oil return tank through a pipeline.

4. The closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load as claimed in claim 1 is characterized by: The closed-loop electro-hydraulic control system includes a two-position two-way solenoid valve, a three-position four-way solenoid valve, and a second directional valve; The second directional valve of the closed-loop electro-hydraulic control system is connected to the power system, and the inlet end of the two-position two-way solenoid valve is connected to the second directional valve through an oil circuit.

5. The closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load as claimed in claim 4 is characterized by: The three-position four-way solenoid valve is connected in parallel with the two-position two-way solenoid valve.

6. The closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load as claimed in claim 5 is characterized by: An electric control signal device is provided between the two-position two-way solenoid valve and the three-position four-way solenoid valve.

7. The closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load as claimed in claim 6 is characterized by: The electric control signal device is connected to the two-position two-way solenoid valve and the three-position four-way solenoid valve respectively.

8. The closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load as claimed in claim 1 is characterized by: The closed-loop electro-hydraulic control system is connected to the safety protection system through a plurality of oil circuits, and a one-way valve is respectively arranged on the oil circuits.

9. The closed-loop electro-hydraulic control system for a wide-table hydraulic press with an anti-eccentric load as claimed in claim 8, characterized in that: The closed-loop electro-hydraulic control opens a branch oil circuit connected to the power system, and the branch oil circuit is connected to the rodless chamber of the piston cylinder.

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