1、 Product Introduction of Electro Hydraulic Servo Two Channel Air Spring Test Stand

The development of this series of testing machines draws on the experience of internationally renowned electro-hydraulic servo dynamic testing machine companies, adopting the development concept of "modularization, modularity, and standardization". The servo controller is a fully digital two channel servo controller, and key supporting components are selected from well-known brands of similar products both domestically and internationally. The stability and reliability of the system have been greatly improved, and the key units and components of the system are manufactured using advanced international technology. The overall performance of the entire testing system is comparable to the product technology level of internationally renowned dynamic testing machine companies. This testing machine is mainly used for axial dynamic and static stiffness testing and fatigue life testing of automotive air springs, as well as axial torsional dynamic and static stiffness testing and fatigue life testing.

2、 Product description of electro-hydraulic servo two channel air spring test bench

1Host: The host is a double column (electroplated) frame structure with servo linear actuators mounted on top.

1.1The crossbeam adopts a hydraulic lifting, hydraulic clamping, and elastic release structure to ensure the stability and reliability of the test, while ensuring that the crossbeam remains locked and stationary in non test states.

1.2The shape of the crossbeam has a three-dimensional sense and is beautiful and elegant.

1.3The crossbeam lifting oil cylinder adopts products from the American sole proprietorship Yurenas, with a beautiful appearance and reliable quality.

1.4The outer surface of the double column is treated with electroplated hard chromium to further enhance its aesthetic appearance and improve its corrosion resistance.

1.5The crossbeam motion (lifting, clamping) drive module is made of domestically produced zero leakage hydraulic components, and the directional valve is manually operated to ensure high reliability during fatigue testing.

1.6The clamping oil cylinder adopts a modular design, and the sealing element adopts imported products from Parker Corporation in the United States to ensure the long-term reliable operation of the testing machine.

1.7Servo linear actuator mounted, built-in in the United StatesSchaevitz SensorscompanyLVDTDisplacement sensor, externally equipped with aerospace Xiangfan aerospace servo valve, with an accuracy not exceeding3uA servo module consisting of a domestically produced Wenzhou Liming (imported from Germany's Hedec technology) precision oil filter and an inlet and outlet oil accumulator with pulse suppression and energy storage functions (Sino British joint venture Fenghua Orel).

1.8The servo valve adopts a high response two-stage servo valve specially designed for the experimental machine of Aerospace Xiangfan Aerospace CompanyHY150-63（7MpaDown flow37L/min，-3dBfrequency response50Hz），satisfy25Hz/±2mmRequirements for amplitude frequency characteristics.

1.9The servo linear actuator designed with modularity, standardization, and modularization has the characteristics of low damping, high response, high lifespan, and large clearance design. The design concept andMTScompanySeries 244 Linear ActuatorsCompletely equivalent.

1.10The sealing components of the servo linear actuator are all imported high-speed sealing components specifically designed for German servo actuators.

1.11The support of the servo linear actuator piston rod breaks the traditional design, adopts non-metallic support and large clearance design, and has the characteristics of high-speed non sintering self-lubricating.

1.12The amplitude limit position of the servo linear actuator is designed with a hydraulic buffer zone to avoid damage caused by uncontrolled operation.

1.13The frequency response of the servo linear actuator is not less than100Hz.

1.14Install load sensors from the American company Shiquan Tianjin.

1.15The front of the host is designed with crossbeam movement and emergency stop operation buttons for easy operation by testers.

2 thatTest systemMainly composed of a host (with one installed on top)20kNServo linear actuator), one500NmThe servo pendulum actuator is installed on the main machine worktable, one unit70L/minIt consists of a constant pressure servo pump station, a two channel oil separation module, a fully digital two channel coordinated loading servo controller, related test software, and other accessories. The control principle block diagram of multi-channel system is shown in the figure1As shown in the diagram, the control block diagram for each channel is as follows2As shown.

image1 System Control Principle Block Diagram

image2 Control block diagram for each channel

3 Measurement and Control SystemSome key components are all made in the United StatesADCompany（ANALOG DEVICE）Designed with the latest high-performance analog devices, it has a high frequency of data acquisition and control, and can achieve5KHz.

u gear: 1、2、5、10；

u Test frequency:0.01-100Hz；

u test waveform Sine wave, square wave, triangular wave, oblique wave;

u Having a stable amplitude,PIDFControl function;

u The experimental software runs onWinXPenvironment,Support Advantech, Advantech, Huabei Industrial Control, etc Single core and dual core industrial control computer.

image3 Test interface

3、 Main technical performance indicators of the electro-hydraulic servo two channel air spring test bench

1Servo linear actuator:

1.1Maximum static test force: ±20kN, press1、10The attenuation factor is calibrated in stages, that is, in2-100%FSAccuracy of indication within the range for each level20%Start ±1%.

1.2Maximum dynamic test force: ±20kNThe amplitude fluctuation is not greater than ± for each level1%FS(Satisfied)《JB/T9397-1999Technical conditions for tensile and compressive fatigue testing machine.

1.3Maximum amplitude of actuator: ±25mmAccuracy of indication20%Start ±0.5%FS.

2Servo pendulum actuator:

2.1Maximum torque:±500NmAccuracy of indication20%FSrise±1%.

2.2Maximum turning angle:±45°Accuracy of indication1%.

3Frequency range:0.001—30Hz.

4Experimental waveform: supported by the controller.

5Specification of constant pressure servo pump station: flow rate70L/min，21MpaMotor power37kW.