金沙城体育投注⎛⎝weRxx⎠⎞ Hydraulic cylinder synchronous lifting control system with rope displacement sensor

爱博体育app

Website map

contact us

  • Shenzhen easie Electric Co., Ltd
  • Hotline: 137-2888-0902
  • Sales line: 0755-85271862
  • Fax: 0755-27083809
  • Email: zetme.com
  • Address: 5 / F, building 8, Honghai building, Hongxing community, Songgang street, Bao'an District, Shenzhen
  • website: http://cn-opticfiber.com

News Center

Synchronous lifting control system of hydraulic cylinder with rope displacement sensor

Issue date: June 25, 2019 Hits: 115
At present, the box of garbage compressor is lifted and lowered by two hydraulic cylinders. The hydraulic system is only controlled by two groups of three position four-way solenoid valve. This method can not realize synchronous control of lifting hydraulic cylinder, which leads to serious tilt of the box and manual adjustment is required to solve the problem of tilt. In practice, manual adjustment of the lifting hydraulic cylinder stroke to control the inclination of the box body, heavy workload, cumbersome process, and adjustment accuracy depends on visual inspection, large error, easy to cause damage to parts.

summary of the invention

This paper provides a synchronous lifting control system of hydraulic cylinder. The system can make the hydraulic cylinder which is responsible for lifting and descending the garbage compressor box to independently control, work at the same time and do not interfere with each other. In addition, the system can make the movement speed of the hydraulic cylinder not be changed by the load change.

Description of drawings

Fig. 1 is a schematic diagram of the application system structure;
 Synchronous lifting control system of hydraulic cylinder with rope displacement sensor

Fig. 2 is the control flow diagram of the application system.
 Synchronous lifting control system of hydraulic cylinder with rope displacement sensor

Specific implementation mode

In order to further explain the present invention in combination with the technical examples in the field.

As shown in Figure 1, the synchronous lifting control system of the hydraulic cylinder in the application comprises a hydraulic station 1, a valve mounting support 2, a bipolar electromagnetic relief valve 3, and a branch oil circuit A and branch oil circuit B.

Branch oil circuit a is set with left speed regulating valve A-1, left three position four-way solenoid valve A-2 and left hydraulic cylinder A-3 from front to back; branch oil circuit B is set with right speed regulating valve B-1, right three position four-way solenoid valve B-2 and right hydraulic cylinder B-3 from front to back;

Bipolar solenoid relief valve 3, left speed regulating valve A-1, right speed regulating valve B-1, left three position four-way solenoid valve a_ 2. Hydraulic station I consists of hydraulic pump 1-1 and oil return filter 1-2, in which the oil outlet of hydraulic pump 1-1 is connected with bipolar electromagnetic relief valve 3, left speed regulating valve A-1 and right speed regulating valve B-1, and oil return filter 1-2 is connected with bipolar electromagnetic relief valve 3, left three position four-way solenoid valve A-2 and right three position four-way solenoid valve B-2;

There is also an electrical system 4 between the bipolar electromagnetic relief valve 3, the left speed regulating valve A-1 and the right speed regulating valve B-1. The electrical system includes PLC controller 4-1 and the left pull rope set on the side of left hydraulic cylinder A-3 Displacement sensor 4-2. The right pull rope is set on the side of B-3 of right hydraulic cylinder Displacement sensor 4-3, lifting and lowering button 4-4, left and right balance button 4-5, left and right balance indicator light 4-6, real-time balance monitoring device 4-7.

The left speed regulating valve A-1 and the right speed regulating valve B-1 in this application are two-way flow control valves composed of a throttle valve in series with a constant differential pressure reducing valve. The orifice of the throttle valve is a thin-walled small hole, and the length diameter ratio of the orifice is 0.5. At present, only throttle valve is used to control the flow, which is affected by the change of load. That is to say, only using the general throttle valve will cause the hydraulic cylinder with small load to act first and the hydraulic cylinder with large load will act later, and the hydraulic cylinder will not be synchronized. The speed regulating valve used in the application connects the throttle valve and the constant differential pressure reducing valve in series, so that the pressure difference Λ P before and after the throttle valve can be kept constant. Through constant adjustment of the valve core of the constant pressure reducing valve, the pressure difference between the inlet and outlet of the throttle valve is ensured to be constant, and the flow rate remains unchanged. In this way, the flow rate is not affected by the load change, and then the speed of the hydraulic cylinder will not change again. Finally, when the left and right hydraulic cylinders work at the same time, they can control each other independently and do not interfere with each other, so as to ensure the stable lifting and falling of the box body.

As shown in Figures 1 and 2, the operation buttons in the electrical system, namely lifting and lowering buttons 4-4 and box left and right balance buttons 4-5, are responsible for sending execution signals to PLC controller 4-1; The left pulling rope displacement sensor 4-2 and right pulling rope displacement sensor 4-3 are mainly used to measure the expansion and contraction length of left hydraulic cylinder a - 3 and right hydraulic cylinder β - 3 in real time, and convert the expansion length into electrical signal and send it to the PLC controller; the left and right balance buttons 4-5 of the box are mainly used for balance indication and balance operation, and the left and right balance indicator light 4-6 of the box is mainly used for fault alarm indication; The PLC controller 4-1 is mainly used to receive and process the signals of the above operation buttons and pull rope displacement sensors; it controls the lifting and lowering of the left hydraulic cylinder A-3 and the right hydraulic cylinder B-3 by controlling the double machine electromagnetic relief valve 3, the left three position four-way solenoid valve A-2 and the right three position four-way solenoid valve B-2.

The real-time balance detection device 4-7 is responsible for real-time detection of the difference between the left pulling rope displacement sensor 4-2 and the right pulling rope displacement sensor 4-3. When the difference value is greater than or equal to 23mm, the system will stop the action of the hydraulic cylinder, and the lifting and lowering button operation is invalid. The real-time balance detection device 4-7 can judge the sensor state: if any sensor of left pull rope displacement sensor 4-2 and right pull rope displacement sensor 4-3 fails, left hydraulic cylinder A-3 and right hydraulic cylinder B-3 stop moving automatically.

Control process:

1. Lifting cylinder lifting synchronization

Press the lifting button in the lifting and lowering button 4-4, the left electromagnet of bipolar solenoid relief valve 3, left three position four-way solenoid valve A-2 and right three position four-way solenoid valve B-2 are powered on. The high-pressure oil is pumped out through hydraulic pump 1-1, and then enters into the rodless chamber of left hydraulic cylinder A-3 and right hydraulic cylinder B-3 through the left speed regulating valve A-1, right speed regulating valve B-1, left three position four-way electromagnetic valve A-2 and right three position four-way solenoid valve B-2 The low-pressure oil passes through the rod cavity of left hydraulic cylinder A-3 and right hydraulic cylinder B-3, left three position four-way solenoid valve A-2, right three position four-way solenoid valve B-2 and oil return filter 1-2, and finally returns to the hydraulic station, and the lifting cylinder moves upward. By initially adjusting the opening size of left speed regulating valve A-1 and right speed regulating valve B-1, the rising synchronization of left hydraulic cylinder A-3 and right hydraulic cylinder B-3 is automatically ensured. In this process, in order to prevent the failure of the left speed regulating valve A-1 and the right speed regulating valve B-1, the left pull wire sensor 4-2 and the right rope displacement sensor 4-3 measure the expansion length of the left hydraulic cylinder A-3 and the right hydraulic cylinder B-3, and feed the difference back to the PLC controller 4-1. If the difference is less than 23mm, it indicates that the left hydraulic cylinder A-3 and the right hydraulic cylinder B-3 rise synchronously. When the left speed regulating valve A-1 and right speed regulating valve B-1 fail, the difference will be greater than or equal to 23mm, and the left hydraulic cylinder A-3 and right hydraulic cylinder B-3 will stop moving automatically. At this time, the left and right balance indicator light 4-6 of the box is on, indicating that the left hydraulic cylinder A-3 and the right hydraulic cylinder B-3 are not rising synchronously. At this time, it is necessary to safely eliminate the problem of left speed regulating valve A-1 and right speed regulating valve B-1. The box must be raised to a proper position to discharge the garbage, and then return to the ground for maintenance. Press the left and right balance button 4-5 of the box, and PLC controller 4-1 will automatically send a signal to the bipolar electromagnetic relief valve 3. The left electromagnet of the three position four-way solenoid valve corresponding to the slow hydraulic cylinder. The slow hydraulic cylinder continues to extend, and the fast hydraulic cylinder stops moving. When the difference between the real-time measurement of the left pulling rope displacement sensor 4-2 and the right pulling rope displacement sensor 4-3 is 0 mm, the surface left hydraulic cylinder A-3 and right hydraulic cylinder B-3 have been synchronized, the hydraulic cylinder with slow rising speed stops acting, and the left and right balance indicator light 4-6 of the box is off. When the problem of left speed regulating valve A-1 and right speed regulating valve B-1 is eliminated, the lifting cylinder lifting action will be synchronized.

2. Lifting cylinder lowering synchronization

Similar to descent synchronization operation

Online Service
share share
Copyright: Shenzhen easie Electric Co., Ltd. record No Yue ICP Bei No. 19052563 Network security No. 44030602003587 Technical support: Xinghai Internet