阅读说明：本技术 一种旋压机模具液压压下控制系统 (Hydraulic pressing control system for spinning machine die ) 是由 赵春江 宁圆盛 王蕊 白峭峰 龙涛 于 2020-04-30 设计创作，主要内容包括：本发明公开一种旋压机模具液压压下控制系统。该系统主要由油箱1、控制电机2、轴向柱塞泵3、电液伺服阀7、非对称液压缸13、旋轮14、控制器17,以及位置传感器15和压力传感器12等部分组成,来实现钢管16的变薄旋压。启动控制电机2带动轴向柱塞泵3转动,分别通过压力传感器12和位置传感器15采集非对称液压缸13两腔的压力信号和活塞杆的位置信号,反馈到系统控制器17中,使系统构成压力控制为内环控制,位置控制为外环控制的双闭环控制系统,通过调节电液伺服阀7的阀芯位移控制流入非对称液压缸13无杆腔的流量来改变液压缸13的压下量,从而改变安装于液压缸13活塞杆上旋轮14的压下量,实现对所旋压的钢管16的壁厚控制。该方法能够明显提高旋压机的控制精度,降低外负载扰动对液压系统稳定性的影响。(The invention discloses a hydraulic pressing control system for a spinning machine die. The system mainly comprises an oil tank 1, a control motor 2, an axial plunger pump 3, an electro-hydraulic servo valve 7, an asymmetric hydraulic cylinder 13, a spinning wheel 14, a controller 17, a position sensor 15, a pressure sensor 12 and the like, and thinning spinning of a steel pipe 16 is realized. The control motor 2 is started to drive the axial plunger pump 3 to rotate, pressure signals of two cavities of the asymmetric hydraulic cylinder 13 and position signals of a piston rod are acquired through the pressure sensor 12 and the position sensor 15 respectively and fed back to the system controller 17, so that the system forms a double closed loop control system with pressure control as inner loop control and position control as outer loop control, the amount of pressing down of the hydraulic cylinder 13 is changed by adjusting the valve core displacement of the electro-hydraulic servo valve 7 to control the flow rate flowing into the rodless cavity of the asymmetric hydraulic cylinder 13, the amount of pressing down of a spinning wheel 14 arranged on the piston rod of the hydraulic cylinder 13 is changed, and the wall thickness control of a spun steel pipe 16 is realized. The method can obviously improve the control precision of the spinning machine and reduce the influence of external load disturbance on the stability of the hydraulic system.)

1. A hydraulic pressure pressing control system for a spinning machine die comprises an oil tank 1, a control motor 2, an axial plunger pump 3, overflow valves 4, 10.1, 10.2, 11.1, 11.2, hydraulic control one-way valves 5, 8.1, 8.2, 8.3, 8.4, two-position three-way reversing valves 6, 9.1, 9.2, electro-hydraulic servo valves 7.1, 7.2, pressure sensors 12.1, 12.2, 12.3, 12.4, asymmetric hydraulic cylinders 13.1, 13.2, spinning wheels 14.1, 14.2, displacement sensors 15.1, 15.2, a steel pipe 16 and a controller 17; the two-position three-way reversing valve 6 is arranged on the manifold block and used for controlling the starting and stopping of the whole system; the overflow valve 4 is arranged on the integrated block to perform overload protection on the system; the action of the spinning machine for pressing down the hydraulic cylinders 13.1 and 13.2 is realized by adjusting the displacement of valve cores of the electro-hydraulic servo valves 7.1 and 7.2 through a controller 17, and the overflow valves 10.1, 10.2, 11.1 and 11.2 are all arranged on the integrated block and used for adjusting and stabilizing the inlet and outlet pressures of the asymmetric hydraulic cylinders 13.1 and 13.2; the hydraulic control one-way valves 5, 8.1, 8.2, 8.3 and 8.4 are also arranged on the manifold block and used for locking the hydraulic cylinders 13.1 and 13.2, so that misoperation of the hydraulic cylinders 13.1 and 13.2 caused by leakage is prevented; the two-position three-way reversing valves 9.1 and 9.2 are arranged on the manifold block and used for switching the working conditions of the system; displacement sensors 15.1 and 15.2 are mounted on piston rods of the hydraulic cylinders 13.1 and 13.2, pressure sensors 12.1, 12.2, 12.3 and 12.4 are mounted on connecting oil paths of the cavities and are respectively used for acquiring position signals of the piston rods and working pressure signals of the two cavities of the hydraulic cylinder during system operation; the rotary wheels 14.1 and 14.2 are fixed on piston rods of the asymmetric hydraulic cylinders 13.1 and 13.2 through hinges; the working principle of the hydraulic system of the spinning machine is as follows:

a) after the control motor 2 and the axial plunger pump 3 are started, the two-position three-way valve 6 is switched to the right position; when the controller 17 controls the electro-hydraulic servo valve 7.1 to be switched to the left position 7.2 to be switched to the right position, pressure oil of the pump 3 enters rodless cavities of the asymmetric hydraulic cylinders (13.1 and 13.2) through the hydraulic control one-way valve 5, the electro-hydraulic servo valves (7.1 and 7.2) and the hydraulic control one-way valves (8.1 and 8.4), oil in the rod cavities flows back to an oil tank through the two-position three-way reversing valves (9.1 and 9.2), the hydraulic control one-way valves (8.2 and 8.3) and the electro-hydraulic servo valves (7.1 and 7.2), and the asymmetric hydraulic cylinders (13.1 and 13.2) fast forward;

b) when the rotary wheels (14.1, 14.2) contact the steel pipe 16, system positions and pressure signals acquired by the displacement sensors (15.1, 15.2) and the pressure sensors (12.1, 12.2, 12.3, 12.4) are fed back to the controller 17, the two-position three-way reversing valve 9.1 is controlled to be switched to the right position and the 9.2 is controlled to be switched to the left position by the controller 17, oil in rod cavities of the asymmetric hydraulic cylinders (13.1, 13.2) flows back to an oil tank through the two-position three-way reversing valves (9.1, 9.2) and overflow valves (10.1, 10.2), and the working conditions of the asymmetric hydraulic cylinders (13.1, 13.2) are changed from fast forward to work forward;

c) according to signals collected by displacement sensors (15.1, 15.2) and pressure sensors (12.1, 12.2, 12.3, 12.4), when the piston rod is detected to move to a target position, the controller 17 controls electro-hydraulic servo valves (7.1, 7.2) to be switched to a neutral position, and the asymmetric hydraulic cylinders (13.1, 13.2) are stopped; after the spinning is finished, the electro-hydraulic servo valve 7.1 is switched to the right position, the electro-hydraulic servo valve 7.2 is switched to the left position, the two-position three-way reversing valve 9.1 is switched to the left position, the electro-hydraulic servo valve 9.2 is switched to the right position, the pressure oil of the pump 3 enters the rod cavities of the asymmetric hydraulic cylinders (13.1, 13.2) through the hydraulic control one-way valve 5, the electro-hydraulic servo valves (7.1, 7.2), the hydraulic control one-way valves (8.2, 8.3) and the two-position three-way reversing valves (9.1, 9.2), the oil in the rod-free cavity is discharged to the oil tank through the hydraulic control one-way valves (8.1, 8.4) and the electro-hydraulic servo valves (7.1, 7.2), and the asymmetric hydraulic cylinders (13.1, 13; when the cylinder is returned to the end point, the electro-hydraulic servo valves (7.1 and 7.2) are switched to the middle position by the controller 17 according to signals collected by the displacement sensor 15 and the pressure sensor 12, the two-position three-way reversing valve 6 is switched to the left position, and the working cycle of the asymmetric hydraulic cylinders (13.1 and 13.2) is ended.

Technical Field

The invention relates to the field of high-precision electro-hydraulic servo control systems, in particular to a hydraulic pressing control system for a spinning machine die.

Background

The spinning machine belongs to metal plastic forming machinery, and due to the characteristics of the powerful spinning technology, the spinning machine is widely applied to aerospace, weaponry and other military and civil industries. At present, the feed driving mode of the spinning machine mainly has two modes: servo motor + ball and electric liquid servo. The first mode is only used for small and medium-sized spinning machines, and the precision of spinning products is low. The other mode is a main mode of the current large-scale high-precision powerful spinning feed driving, can meet the requirement of large selection pressure and has good shock resistance. Feeding systems of a large vertical numerical control powerful spinning machine SY-100L and VL-16 CNC and a horizontal powerful spinning machine SY-6 CNC and SY 3D-400 CNC which are independently researched and developed in China are all controlled by electro-hydraulic control. The numerical control powerful spinning machines produced by some famous spinning machine manufacturers abroad also adopt an electro-hydraulic feed driving system. Therefore, the development of the electro-hydraulic control system becomes a key problem and has important practical significance for realizing high-performance powerful spinning processing of large-sized parts.

The invention provides a hydraulic pressing control system of a spinning machine die based on a spinning machine electro-hydraulic system control method, and aims to improve the position control precision of a pressing hydraulic cylinder of the spinning machine die and reduce the influence of external load disturbance on the stability of a system.

Disclosure of Invention

The invention provides a hydraulic pressing control system for a spinning machine die, which aims to improve the position control precision of the hydraulic pressing control system for the spinning machine die.

The invention is realized by the following technical scheme: referring to fig. 1 and 2, the hydraulic control system of the spinning machine includes an oil tank 1, a control motor 2, an axial plunger pump 3, an overflow valve 4, 10.1, 10.2, 11.1, 11.2, a hydraulic control check valve 5, 8.1, 8.2, 8.3, 8.4, a two-position three-way directional valve 6, 9.1, 9.2, an electro-hydraulic servo valve 7.1, 7.2, a pressure sensor 12.1, 12.2, 12.3, 12.4, an asymmetric hydraulic cylinder 13.1, 13.2, a spinning wheel 14.1, 14.2, a displacement sensor 15.1, 15.2, a steel pipe 16, and a controller 17; wherein, the two-position three-way reversing valve 6 is arranged on the manifold block and used for controlling the start and stop of the whole system; the overflow valve 4 is arranged on the integrated block to carry out overload protection on the system; the action of the spinning machine for pressing down the hydraulic cylinders 13.1 and 13.2 is realized by adjusting the valve core displacement of the electro-hydraulic servo valves 7.1 and 7.2 by the controller 17, and the overflow valves 10.1, 10.2, 11.1 and 11.2 are all arranged on the integrated block and used for adjusting and stabilizing the inlet and outlet pressure of the asymmetric hydraulic cylinders 13.1 and 13.2; the hydraulic control one-way valves 5, 8.1, 8.2, 8.3 and 8.4 are also arranged on the manifold block and used for locking the hydraulic cylinders 13.1 and 13.2, so that the hydraulic cylinders 13.1 and 13.2 are prevented from being mistakenly operated due to leakage; two-position three-way reversing valves 9.1 and 9.2 are arranged on the manifold block and used for switching the working conditions of the system; displacement sensors 15.1 and 15.2 are arranged on piston rods of the hydraulic cylinders 13.1 and 13.2, pressure sensors 12.1, 12.2, 12.3 and 12.4 are arranged on connecting oil paths of the cavities and are respectively used for acquiring displacement signals of the piston rods and working pressure signals of the two cavities of the hydraulic cylinders when the system works; the rotary wheels 14.1 and 14.2 are fixed on the piston rods of the asymmetric hydraulic cylinders 13.1 and 13.2 through hinges; the specific working method is as follows:

a) after the control motor 2 and the axial plunger pump 3 are started, the two-position three-way valve 6 is switched to the right position. When the controller 17 controls the electro-hydraulic servo valve 7.1 to be switched to the left position 7.2 to be switched to the right position, pressure oil of the pump 3 enters the rodless cavities of the asymmetric hydraulic cylinders (13.1 and 13.2) through the hydraulic control one-way valve 5, the electro-hydraulic servo valves (7.1 and 7.2) and the hydraulic control one-way valves (8.1 and 8.4), and oil in the rod cavities flows back to an oil tank through the two-position three-way reversing valves (9.1 and 9.2), the hydraulic control one-way valves (8.2 and 8.3) and the electro-hydraulic servo valves (7.1 and 7.2). The actual displacement signals x of the piston rods of the asymmetric hydraulic cylinders (13.1, 13.2) are acquired through displacement sensors (15.1, 15.2), fed back to the controller 17, compared with a given displacement signal us, output to electro-hydraulic servo valves (7.1, 7.2) through the controller, and the actions of the asymmetric hydraulic cylinders (13.1, 13.2) are controlled through adjusting the valve core displacement of the electro-hydraulic servo valves (7.1, 7.2), so that position closed-loop control is formed. Pressure signals P1 and P2 on oil paths of oil inlets and oil outlets of the asymmetric hydraulic cylinders (13.1 and 13.2) are acquired through pressure sensors (12.1, 12.2, 12.3 and 12.4), are fed back to a pressure-position conversion model, are converted into signal data which can be added or subtracted with displacement signals, are compared with a given displacement signal us, are output to electro-hydraulic servo valves (7.1 and 7.2) through a controller 17, and the actions of the asymmetric hydraulic cylinders (13.1 and 13.2) are controlled by adjusting the valve core displacement of the electro-hydraulic servo valves (7.1 and 7.2), so that pressure closed-loop control is formed. Finally, the position and the pressure of the hydraulic pressing control system of the spinning machine die are respectively controlled by two closed loops to realize fast forwarding of the system;

b) when the rotary wheels (14.1, 14.2) contact the steel pipe 16, the actual displacement signals x of the piston rods of the asymmetric hydraulic cylinders (13.1, 13.2) are collected through the displacement sensors (15.1, 15.2), the pressure signals P1 and P2 on oil passages of oil inlets and oil outlets of the asymmetric hydraulic cylinders (13.1, 13.2) are collected through the pressure sensors (12.1, 12.2, 12.3, 12.4) and fed back to the pressure-position conversion model, converting into signal data which can be added or subtracted with the displacement signal, comparing the collected signal with the given displacement signal us and outputting to the controller 17, the two-position three-way reversing valve 9.1 is switched to the right position and the two-position three-way reversing valve 9.2 is switched to the left position through the controller 17, oil in rod cavities of the asymmetric hydraulic cylinders (13.1 and 13.2) flows back to an oil tank through the two-position three-way reversing valves (9.1 and 9.2) and overflow valves (10.1 and 10.2), so that the position and the pressure of a hydraulic pressing control system of a spinning machine die are respectively switched from fast feeding to working feeding under the action of two closed-loop controls;

c) according to signals collected by the displacement sensors (15.1, 15.2) and the pressure sensors (12.1, 12.2, 12.3, 12.4), when the piston rod is detected to move to a target position, the controller 17 controls the electro-hydraulic servo valves (7.1, 7.2) to be switched to a neutral position, and the asymmetric hydraulic cylinders (13.1, 13.2) are stopped. After the spinning is finished, the electro-hydraulic servo valve 7.1 is switched to the right position, the electro-hydraulic servo valve 7.2 is switched to the left position, the two-position three-way reversing valve 9.1 is switched to the left position, the electro-hydraulic servo valve 9.2 is switched to the right position, the pressure oil of the pump 3 enters the rod cavities of the asymmetric hydraulic cylinders (13.1, 13.2) through the hydraulic control one-way valve 5, the electro-hydraulic servo valves (7.1, 7.2), the hydraulic control one-way valves (8.2, 8.3) and the two-position three-way reversing valves (9.1, 9.2), the oil without the rod cavities is discharged to the oil tank through the hydraulic control one-way valves (8.1, 8.4) and the electro-hydraulic servo valves (7.1, 7.2), and the asymmetric hydraulic cylinders (13.1, 13.2. When the cylinder is returned to the end point, the electro-hydraulic servo valves (7.1 and 7.2) are switched to the middle position by the controller 17 according to signals collected by the displacement sensor 15 and the pressure sensor 12, the two-position three-way reversing valve 6 is switched to the left position, and the working cycle of the asymmetric hydraulic cylinders (13.1 and 13.2) is ended.

Drawings

Fig. 1 is a schematic diagram of the hydraulic pressing system of the spinning machine of the present invention.

Fig. 2 is a control block diagram of the hydraulic depressing system of the spinning machine.

In the figure: the hydraulic control system comprises an oil tank 1, a control motor 2, an axial plunger pump 3, overflow valves 4, 10.1, 10.2, 11.1 and 11.2, hydraulic control one-way valves 5, 8.1, 8.2, 8.3 and 8.4, two-position three-way reversing valves 6, 9.1 and 9.2, electro-hydraulic servo valves 7.1 and 7.2, pressure sensors 12.1, 12.2, 12.3 and 12.4, asymmetric hydraulic cylinders 13.1 and 13.2, rotary wheels 14.1 and 14.2, displacement sensors 15.1 and 15.2, a steel pipe 16 and a controller 17.

Detailed Description

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

As shown in fig. 1 and 2, after the control motor 2 and the axial plunger pump 3 are started, the two-position three-way valve 6 is switched to the right position. When the controller 17 controls the electro-hydraulic servo valve 7.1 to be switched to the left position 7.2 to be switched to the right position, pressure oil of the pump 3 enters the rodless cavities of the asymmetric hydraulic cylinders (13.1 and 13.2) through the hydraulic control one-way valve 5, the electro-hydraulic servo valves (7.1 and 7.2) and the hydraulic control one-way valves (8.1 and 8.4), and oil in the rod cavities flows back to an oil tank through the two-position three-way reversing valves (9.1 and 9.2), the hydraulic control one-way valves (8.2 and 8.3) and the electro-hydraulic servo valves (7.1 and 7.2). The actual displacement signals x of the piston rods of the asymmetric hydraulic cylinders (13.1, 13.2) are acquired through displacement sensors (15.1, 15.2), fed back to the controller 17, compared with a given displacement signal us, output to electro-hydraulic servo valves (7.1, 7.2) through the controller, and the actions of the asymmetric hydraulic cylinders (13.1, 13.2) are controlled through adjusting the valve core displacement of the electro-hydraulic servo valves (7.1, 7.2), so that position closed-loop control is formed. Pressure signals P1 and P2 on oil paths of oil inlets and oil outlets of the asymmetric hydraulic cylinders (13.1 and 13.2) are acquired through pressure sensors (12.1, 12.2, 12.3 and 12.4), are fed back to a pressure-position conversion model, are converted into signal data which can be added or subtracted with displacement signals, are compared with a given displacement signal us, are output to electro-hydraulic servo valves (7.1 and 7.2) through a controller 17, and the actions of the asymmetric hydraulic cylinders (13.1 and 13.2) are controlled by adjusting the valve core displacement of the electro-hydraulic servo valves (7.1 and 7.2), so that pressure closed-loop control is formed. And finally, the position and the pressure of the hydraulic pressing control system of the spinning machine die are respectively controlled by two closed loops to realize the fast forwarding of the system. When the rotary wheels (14.1, 14.2) contact the steel pipe 16, the actual displacement signals x of the piston rods of the asymmetric hydraulic cylinders (13.1, 13.2) are collected through the displacement sensors (15.1, 15.2), the pressure signals P1 and P2 on oil passages of oil inlets and oil outlets of the asymmetric hydraulic cylinders (13.1, 13.2) are collected through the pressure sensors (12.1, 12.2, 12.3, 12.4) and fed back to the pressure-position conversion model, converting into signal data which can be added or subtracted with the displacement signal, comparing the collected signal with the given displacement signal us and outputting to the controller 17, the two-position three-way reversing valve 9.1 is switched to the right position and the two-position three-way reversing valve 9.2 is switched to the left position through the controller 17, oil in rod cavities of the asymmetric hydraulic cylinders (13.1 and 13.2) flows back to an oil tank through the two-position three-way reversing valves (9.1 and 9.2) and overflow valves (10.1 and 10.2), and the position and the pressure of a hydraulic pressing control system of a spinning machine die are respectively switched from fast feeding to working feeding under the action of two closed-loop controls. According to signals collected by the displacement sensors (15.1, 15.2) and the pressure sensors (12.1, 12.2, 12.3, 12.4), when the piston rod is detected to move to a target position, the controller 17 controls the electro-hydraulic servo valves (7.1, 7.2) to be switched to a neutral position, and the asymmetric hydraulic cylinders (13.1, 13.2) are stopped. After the spinning is finished, the electro-hydraulic servo valve 7.1 is switched to the right position, the electro-hydraulic servo valve 7.2 is switched to the left position, the two-position three-way reversing valve 9.1 is switched to the left position, the electro-hydraulic servo valve 9.2 is switched to the right position, the pressure oil of the pump 3 enters the rod cavities of the asymmetric hydraulic cylinders (13.1, 13.2) through the hydraulic control one-way valve 5, the electro-hydraulic servo valves (7.1, 7.2), the hydraulic control one-way valves (8.2, 8.3) and the two-position three-way reversing valves (9.1, 9.2), the oil without the rod cavities is discharged to the oil tank through the hydraulic control one-way valves (8.1, 8.4) and the electro-hydraulic servo valves (7.1, 7.2), and the asymmetric hydraulic cylinders (13.1, 13.2. When the cylinder is returned to the end point, the electro-hydraulic servo valves (7.1 and 7.2) are switched to the middle position by the controller 17 according to signals collected by the displacement sensor 15 and the pressure sensor 12, the two-position three-way reversing valve 6 is switched to the left position, and the working cycle of the asymmetric hydraulic cylinders (13.1 and 13.2) is ended.