Guang Lin Wang

Study on Non-Burr & Sharp-Edge Protecting Grinding Method of Functional Edge

This paper researches on the formation mechanism of functional edge (e.g. throttle edge of servo valve’s valve core) during grinding process, and presents due to plastic deformation which is extruded by grinding wheel, burrs are appeared on the edge, and furthermore the edge becomes not sharp. This paper provides a non-burr & sharp-edge protecting grinding method which is named protection part method, used a protection part to protect the edge out of burrs and be sharp. Experimental data prove that utilizing protection part which is the same hardness with the processed part and an appropriate magnitude of interference parameter, this method can assure non-burr & sharp-edge protecting grinding of functional edge.

Simulation Research on Effect of Diametral Clearance of Spool Valve to Valve Orifice Discharge Characteristic

This paper studies the effect of spool valve diametral clearance of electro-hydraulic servo valve on orifice discharge characteristic. To ensure that the freely sliding between spool and sleeve, there must be given diametral clearance between spool and sleeve, which will have an impact on valve orifice discharge characteristic, this paper first individually sets up a 3D models of clearance from 0 to 5 μm, opening value from 0 to 40 μm, then calculates each model’s discharge on the condition that valve orifice’s inlet and outlet differential pressure is constant, finally according to the result of the discharge plots the diametral clearance curve of spool valve. The quantitative numerical relationship of diametral clearance and spool valve characteristic index is given after doing the analysis, Finally, an experimental verification of the simulation results is to be done to prove the simulation results are correct and reliable. The research of this paper provides the basic guidelines for spool valve designing and testing.

Development and Experimental Study of Magnetic Property for Servo Valve Torque Motor

Torque motor is an electrical-mechanical converter of servo valve, is bridge which connects the electrical devices and hydraulic devices, is one of key components of servo valve. The permanent magnet torque motor is studied in this paper. As key parameters of design of servo valve, the magnetic property of torque motor determines magnitude of the electromagnetic torque. At present, many manufactures of servo valve pays more attention on the test of integral servo valve. The design of torque motor also bases on experience, lacking of specialized tool for torque motor test. This paper described the principle of magnetic property of the test, developed a test system for magnetic characteristics, and established the relationship between the electromagnetic torque and current control current, and the relationship between output angular displacement and control current.

Measurement of Armature Components' Synthetic Stiffness Based on Torque and Grating Ruler Sensor

The synthetic stiffness measurement principle of Armature Components which is similar to the actual working condition has been proposed. The synthetic stiffness measurement system based on the measurement principle has been established, the composition of this system has been introduced and the realization methods of the single couples loading and torque and angle measurement has been introduced in detail. And related experiments has been conducted. Through analysis the experiment data, the performance of organization has been tested, and so does the rationality of the measurement principle which is proposed.

Pneumatic Measurement Approach for Form Tolerances of Inner Hole in Spool Valve

Pneumatic measurement and genetic algorithm based approach for form tolerances, including the cylindricity error, circularity error and straightness error of axis, of inner hole in spool valve are studied in this paper. A differential pressure type of pneumatic comprehensive measurement approach is put forward, which applies the pneumatic nozzle scanning measurement principle. The minimum zone evaluation and calculation approach for form tolerances based on an improved genetic algorithm is presented considering the characteristics of the measuring point. Finally, the automatic measurement experiment is developed, which can simultaneously measure and evaluate the form tolerances of inner hole in one process.

Study on Automatic Measurement of Valve Orifice Characteristic Based on Pneumatic Flow Method

Spool valve orifice flow characteristic of servo valve plays an important role in the spool valve overlap measurement and manufacturing quality analysis of servo valve. The liner segment of flow characteristic curve could be used to calculate the overlap, and the non-linear segment could be used to evaluate the manufacturing quality of servo valve. This paper analyzed the valve orifice characteristic measurement based on the pneumatic flow method in detail, developed an automatic pneumatic measurement apparatus for valve orifice characteristic and spool valve overlap based on the thermal mass flow sensor AWM2300, verified the measurement accuracy and non-repeated error of this apparatus, and adopted the overlap as investigated object to contrast the measurement results by pneumatic flow method with by pneumatic pressure method. The non-repeated error of overlap measurement by pneumatic flow method did not exceed ±0.5(m, and the experimental results indicated that the automatic pneumatic flow measurement can excellently satisfy the actual requirement in the production of servo valve.

Study on Fluid Process Measurement Technology

Process Measurement is a measuring method which is accompanied with process of the manufacture of work piece. This paper puts forward a new concept of fluid process measurement, and provides four types of fluid process measurements, which are, pressure pneumatic process measurement, flow pneumatic process measurement, pressure hydraulic process measurement, and flow hydraulic process measurement, and establishes the mathematical and physical modal for them. This paper also provides an example of the application of this measurement method. This measurement has a good prospect, because it can deal with the work pieces with high-precision, complex shape and which are hard to be measured in the machining process.

Research of Grinding Concave Paraboloiding Piece by Spherical Grinding Wheel

Aiming at the ultra-sophisticated combined working machine tool that was developed, the motion style of the machine tool when abrasive machining a sort of inward-curving-parabolic shape optical aspherical surface device is analysed, according to the equation of the machined part’s surface, the relative movement locus between the cutter and the machined part can be established while using a spherical grinding wheel as grinding cutter. The caliber of the paraboloid that to be processed is analysed, and the grinding wheels installation angle is chosen, as well as the cutting speed of the cutting spot is analysed, the abrasive model in ideal condition is analysed, the basis is based for error compensating.

UCBO Hydraulic Oil and Application on Hydraulic Measurement for Laval Nozzle Throat Diameter

This paper proposes a hydraulic measurement model for measuring the Laval nozzle throat diameter size. Based on measurement principle of liquid pressure – flowrate, we can get the size of Laval nozzle throat diameter by measuring the fluid flowrate through hydraulic measurement model at the fixed pressure. With good viscosity-temperature performance, low temperature performance and oxidation stability, UCBO aviation hydraulic oil is selected as the measuring medium. In the hydraulic measurement model, the diameter of the mandrel which can be regarded as gauge will directly affect the sensitivity of diameter measurement. Therefore we need to optimize the design of the mandrel of the hydraulic model.

Design of the Auto-Stiffness Measuring Instrument for Electro Hydraulic Servo Valve Elastic Element

The electro-hydraulic servo valve is the essential component of the electro-hydraulic servo control, and it was mainly used on many fields such as aviation, aerospace and navigation etc.People use the electro-hydraulic servo valve to drive plenty of loads. The electro-hydraulic servo valve has many advantages such as fast dynamic response, high control precision, and longevity. Hence, for the elastic element of the electro-hydraulic, which works as the significant feed-back component the characteristic of the stiffness has played an essential role in the electro-hydraulic servo. Based on the previous research of the technology automation and inspection experiment, this paper proposes an auto-stiffness admeasuring apparatus for the elastic element of the Hydraulic servo. and the experiment research has been proceeded. The experimental result shows that, the auto-stiffness admeasuring apparatus has the advantages of high precision, high automation; it can be well used in the productive practice.