CN102744345B - Forging manipulator buffer cylinder hydraulic system - Google Patents

Abstract

The invention discloses a buffer cylinder hydraulic system of a forging manipulator. It includes oil supply port, proportional directional valve, relief valve, check valve, buffer cylinder, pilot relief valve, solenoid directional valve, oil return port, displacement sensor, displacement setting signal, subtractor and PID controller. The invention utilizes the composite multi-chamber structure of the buffer cylinder of the forging manipulator, and integrates the passive buffer system with pilot overflow valve and the active displacement closed-loop control system with proportional directional valve into one buffer cylinder, which can not only realize the The passive buffering function of the clamp has the displacement closed-loop control function required by the buffering system of the forging manipulator, and has the characteristics of simple control and complete functions. The multi-cavity buffering method of the buffer cylinder of the system can provide greater buffering force with the same diameter of the buffer cylinder. In addition, due to fewer proportional control elements, the reliability of the system is higher.

Description

Forging manipulator buffer cylinder hydraulic system

technical field

The invention relates to a buffer cylinder hydraulic system, in particular to a buffer cylinder hydraulic system of a forging manipulator.

Background technique

The special working condition linked with the forging press requires that the tongs of the forging manipulator must have both passive buffering and active control functions in the horizontal direction. Most buffer cylinder hydraulic systems currently exist only have passive buffering functions and cannot realize The active control of the buffer cylinder limits the flexibility of the manipulator clamp in the horizontal direction. After searching the existing technology, it is found that the Chinese invention patent with the application number 200910153528.1 records a "horizontal buffer cylinder hydraulic system for forging manipulator", which realizes passive buffering and active buffering by means of a hydraulic cylinder with multiple chambers and piston rods. control function, but the structure of the buffer cylinder described in this patent is relatively complicated, and the force buffer system and the displacement closed-loop control system are coupled in the same oil circuit.

Contents of the invention

In order to simplify the structure of the buffer cylinder and reduce the coupling characteristics between the two functional oil circuits of the buffer system of the forging manipulator, the purpose of the present invention is to provide a hydraulic system of the buffer cylinder of the forging manipulator, which separates the two functions of passive buffering and active control , respectively controlled by different oil circuits, used to provide buffer force when working in passive working conditions, and used to control the displacement and speed of the buffer cylinder when working in active working conditions.

The technical scheme adopted in the present invention is:

The port P of the proportional directional valve of the present invention is respectively connected with the oil supply port of the oil source and the port P of the electromagnetic directional valve; The cylinder rear cavity is connected; the B port of the proportional directional valve is respectively connected with the inlet of the front cavity relief valve, the outlet of the front cavity check valve, and the front cavity of the buffer cylinder; the T port of the proportional directional valve is respectively connected with the outlet of the pilot relief valve , T port of electromagnetic directional valve, oil return port of oil source, outlet of relief valve in rear chamber, outlet of relief valve in front chamber, inlet of check valve in rear chamber, inlet of check valve in front chamber, rear slide of buffer cylinder The block chamber is connected with the front slider chamber of the buffer cylinder; the middle chamber of the buffer cylinder is connected with the outlet of the oil supply check valve and the inlet of the pilot overflow valve; the A port of the electromagnetic directional valve is connected with the inlet of the oil supply check valve; the displacement The sensor is installed on the buffer cylinder piston rod of the buffer cylinder; the signal output port of the displacement sensor is connected with the signal input port of the displacement controller; the signal output port of the displacement controller is connected with the signal input port of the proportional directional valve.

Described displacement controller comprises the displacement setting signal that operator gives, subtractor and PID controller; Displacement setting signal output signal makes difference with the output signal of displacement sensor at subtractor place; The signal output port of subtractor and The signal input port of the PID controller is connected; the signal output port of the PID controller is connected with the signal input port of the proportional directional valve.

The P port of the proportional directional valve is an oil inlet, the T port is an oil return port, the A port is an oil outlet or an oil return port, and the B port is an oil return port or an oil outlet; the P port of the electromagnetic directional valve is The oil inlet port, the T port is the oil return port, and the A port is the oil outlet or oil return port.

The beneficial effects that the present invention has are:

1) Complete functions, integrating passive buffering and active control functions.

2) The hydraulic oil circuits of the passive buffer function and the active control function are relatively independent, and the control is simple.

3) The cushioning process is provided by the two chambers of the buffer cylinder, the front chamber or the rear chamber, which can provide greater buffering force.

4) In addition to the proportional directional valve, the system has no other proportional control components, and the system has high reliability.

Description of drawings

The accompanying drawing is a schematic diagram of the structure and principle of the buffer cylinder hydraulic system of the forging manipulator.

In the attached drawings: 1. Oil supply port, 2. Proportional directional valve, 3. Rear chamber relief valve, 4. Front chamber relief valve, 5. Rear chamber check valve, 6. Front chamber check valve, 7. Buffer cylinder, 7-1. Buffer cylinder barrel, 7-2. Buffer cylinder piston rod, 7-3. Buffer cylinder rear slider, 7-4. Buffer cylinder front slider, 7-5. Buffer cylinder rear Cavity, 7-6. Rear slider cavity of buffer cylinder, 7-7. Middle cavity of buffer cylinder, 7-8. Front slider cavity of buffer cylinder, 7-9. Front cavity of buffer cylinder, 8. Oil supply check valve, 9. Pilot relief valve, 10. Electromagnetic directional valve, 11. Oil source return port, 12. Displacement sensor, 13. Displacement controller, 14. Displacement setting signal, 15. Subtractor, 16. PID controller .

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and examples of implementation.

As shown in the drawings, the present invention includes a buffer cylinder 7; the P port of the proportional directional valve 2 is connected with the oil supply port 1 and the P port of the electromagnetic directional valve 10 respectively; the A port of the proportional directional valve 2 is connected with the rear chamber overflow The inlet of the flow valve 3, the outlet of the one-way valve 5 in the rear chamber, and the rear chamber 7-5 of the buffer cylinder are connected; the B port of the proportional directional valve 2 is connected with the inlet of the relief valve 4 in the front chamber and the outlet of the one-way valve 6 in the front chamber respectively. , the buffer cylinder front cavity 7-9 connection; the T port of the proportional directional valve 2 is respectively connected with the outlet of the pilot relief valve 9, the T port of the electromagnetic directional valve 10, the oil source return port 11, and the port of the rear cavity relief valve 3 The outlet, the outlet of the front chamber overflow valve 4, the inlet of the rear chamber check valve 5, the inlet of the front chamber check valve 6, the buffer cylinder rear slider chamber 7-6, and the buffer cylinder front slider chamber 7-8 are connected; The middle cavity 7-7 of the buffer cylinder is connected with the outlet of the oil supply check valve 8 and the inlet of the pilot overflow valve 9; the A port of the electromagnetic directional valve 10 is connected with the inlet of the oil supply check valve 8; the displacement sensor 12 is installed on On the buffer cylinder piston rod 7-2 of the buffer cylinder 7; the signal output port of the displacement sensor 12 is connected with the signal input port of the displacement controller 13; the signal output port of the displacement controller 13 is connected with the signal input port of the proportional directional valve 2.

Described displacement controller 13 comprises operator's given displacement setting signal 14, subtractor 15 and PID controller 16; Displacement setting signal 14 output signals make difference with the output signal of displacement sensor 12 at subtractor 15 place; The signal output port of the subtractor 15 is connected with the signal input port of the PID controller 16 ; the signal output port of the PID controller 16 is connected with the signal input port of the proportional directional valve 2 .

The P port of the proportional directional valve 2 is the oil inlet, the T port is the oil return port, the A port is the oil outlet or the oil return port, and the B port is the oil return port or the oil outlet. When the proportional directional valve 2 works When it is in the left position, port A is connected to port P, which is the oil outlet port, and port B is connected to port T, which is the oil return port. When the proportional directional valve 2 is working in the right position, port A is connected to port T, which is the oil return port. Port B is connected to port P and is the oil outlet; port P of the electromagnetic directional valve 10 is the oil inlet, port T is the oil return port, and port A is the oil outlet when the electromagnetic directional valve 10 is powered off. When the power is on, it is the oil return port; the signal input ports of the pilot relief valve 9 and the electromagnetic directional valve 10 are connected with the PLC controller of the manipulator, and the working position and state of the hydraulic valve are controlled by it.

Buffer cylinder 7 is made up of buffer cylinder barrel 7-1, buffer cylinder piston rod 7-2, buffer cylinder rear slider 7-3, buffer cylinder front slider 7-4, wherein buffer cylinder barrel 7-1 is a fixed end , the buffer cylinder piston rod 7-2 is the mobile end, and the relative motion between the two realizes the buffering and displacement control of the buffer cylinder of the forging manipulator; the front slider 7-3 of the buffer cylinder and the rear slider 7-4 of the buffer cylinder can both be used Relative buffer cylinder barrel 7-1 motion. The buffer cylinder cavity includes buffer cylinder rear cavity 7-5, buffer cylinder rear slider cavity 7-6, buffer cylinder middle cavity 7-7, buffer cylinder front slider cavity 7-8, buffer cylinder front cavity 7-9, etc. Two chambers, wherein the rear slider cavity 7-6 of the buffer cylinder and the front slider cavity 7-8 of the buffer cylinder are directly connected to the oil source return port 10; the pistons of the rear cavity 7-5 of the buffer cylinder and the front cavity 7-9 of the buffer cylinder The effective action areas are equal, and for the proportional directional valve 2, the two cavities act as a symmetrical hydraulic cylinder.

The buffer system works in passive buffer mode by default, as shown in the attached figure, at this time, the pilot relief valve 9 and the electromagnetic directional valve 10 are not powered, the output signal of the displacement controller 13 is zero, and the proportional directional valve 2 is in the neutral position , the buffer movement of the buffer cylinder 7 is realized by the pilot relief valve 9 . When the buffer cylinder piston rod 7-2 is under pressure, the oil pressure in the buffer cylinder middle chamber 7-7 and the buffer cylinder rear chamber 7-5 rises, and the oil pressure in the two chambers exceeds the pilot relief valve 9 and the overflow pressure of the relief valve 3 in the rear chamber, the oil overflows through the two relief valves respectively, and the piston rod 7-2 of the buffer cylinder and the front slider 7-4 of the buffer cylinder retreat to realize the thrust compliance of the manipulator. At this time, the buffer cylinder front cavity 7-9 is replenished with hydraulic fluid by the front cavity check valve 6 to prevent the cavity from being sucked empty. Since the buffer cylinder middle chamber 7-7 has a large effective force-bearing area, it provides the main buffer force, and the buffer cylinder rear chamber 7-5 provides the auxiliary buffer force. After the buffer action is completed, the external pressure disappears. At this time, the oil in the oil supply port 1 of the oil source passes through the electromagnetic directional valve 10 to open the oil supply check valve 8, and flows into the buffer cylinder middle chamber 7-7, forcing the buffer cylinder front chamber 7 The oil at -9 flows into the oil source and oil return port 11 through the front chamber overflow valve 4 to realize the reset of the buffer cylinder 7. Similarly, if the buffer cylinder piston rod 7-2 bears too much tension, the piston rod and the buffer cylinder rear slider 7-3 move forward, forcing the oil in the buffer cylinder middle cavity 7-7 and the buffer cylinder front cavity 7-9 to The tension compliance of the buffer cylinder is realized through the relief of the pilot relief valve 9 and the relief valve 4 of the front cavity respectively, and the reset process is similar to the reset process of the pressure buffer.

When the buffer system works in the active control mode, the pilot overflow valve 9 is energized to unload, and the electromagnetic directional valve 10 is energized to change direction. At this time, the oil in the buffer cylinder cavity 7-7 is unloaded, and the hydraulic pressure acting on the buffer cylinder 7 is small, while the oil in the buffer cylinder rear cavity 7-5 and the buffer cylinder front cavity 7-9 flows by displacement Controller 13 and proportional directional valve 2 control.

Claims (1)

1. a forging manipulator cushion dashpot hydraulic system, comprises cushion dashpot (7); It is characterized in that: the P mouth of proportional direction valve (2) is connected with the P mouth of oil sources oil-feed port (1), electromagnetic direction valve (10) respectively; The A mouth of proportional direction valve (2) is connected with entrance, the outlet of back cavity check valve (5), the cushion dashpot back cavity (7-5) of back cavity overflow valve (3) respectively; The B mouth of proportional direction valve (2) is connected with entrance, the outlet of ante-chamber check valve (6), the cushion dashpot ante-chamber (7-9) of ante-chamber overflow valve (4) respectively; The T mouth of proportional direction valve (2) is connected with outlet, the T mouth of electromagnetic direction valve (10), oil sources oil return opening (11), the outlet of back cavity overflow valve (3), the outlet of ante-chamber overflow valve (4), the entrance of back cavity check valve (5), the entrance of ante-chamber check valve (6), cushion dashpot rear slider chamber (7-6), the cushion dashpot front-slider chamber (7-8) of pilot operated compound relief valve (9) respectively; Cushion dashpot lumen (7-7) is connected with the outlet of oil feed non-return valve (8), the entrance of pilot operated compound relief valve (9); The A mouth of electromagnetic direction valve (10) is connected with the entrance of oil feed non-return valve (8); Displacement transducer (12) is arranged on the cushion dashpot piston rod (7-2) of cushion dashpot (7); Displacement transducer (12) signal output is connected with displacement controller (13) signal input; The signal output of displacement controller (13) is connected with the signal input of proportional direction valve (2);

Described displacement controller (13) comprises the given displacement setting signal (14) of operating personnel, subtracter (15) and PID controller (16); It is poor that displacement setting signal (14) output signal is located with the output signal of displacement transducer (12) at subtracter (15); The signal output of subtracter (15) is connected with the signal input of PID controller (16); The signal output of PID controller (16) is connected with the signal input of proportional direction valve (2);

The P mouth of described proportional direction valve (2) is oil-in, and T mouth is oil return opening, and A mouth is oil-out or oil return opening, and B mouth is oil return opening or oil-out; The P mouth of electromagnetic direction valve (10) is oil-in, and T mouth is oil return opening, and A mouth is oil-out or oil return opening.

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