Papers by Author: Shao Bo Chen

Abstract: Medium frequency induction heating is a kind of energy-saving heating method. Now it has been applied to industrial heating craft, and it reveals that it has wide application prospect. However, due to the problem of electromagnetic radiation, it is extremely necessary to do some detection and protection. Based on this study background and according to the standards of EN62233:2008 Measurement Methods for Electromagnetic Fields of Household Appliances and Similar Apparatus with Regard to the Human Exposure in European Union, the guidelines of ICNIRP (the abbreviation of International Commission for Non-Ionizing Radiation Protection) with the international authority are adopted on the protection standards of electromagnetic field. And a new detection system for three-dimensional alternating electromagnetic radiation has been developed, and is used to detect electromagnetic radiation generated in industrial medium frequency induction heating. In the laboratory test, the precise instrument imported in Germany was a comparison of the equipment. And when testing the same heating object, the test results had better consistency between the precise instrument and the new detection system. On the basis of test requirements in EN62233, a comprehensive value of electromagnetic field intensity has been gotten after the superposition of every effective harmonic component in electromagnetic field, and the prompt of exceed standard is given in the paper, which gives a viable reference and guidance for electromagnetic radiation detection of medium frequency induction heating. After experimental debugging and system calibration in the laboratory, the detection system is running stably and accurately, and reaches the design requirements.

Abstract: Aiming at the shaft pressing and assembling process for steel shaft and small gear, which is frequent in toy gear reducer assembling, a reconfigurable and multi-station auto shaft pressing and assembling machine had been developed. In the machine, steel shaft and small gear are positioned in a pre-positioned fixture in advance. The assembling process is carried out in three stations simultaneously. It makes the machines efficiency become higher. Applying the reconfigurable design concept, the machine can be divided into basal modules and changeable modules. The changeable modules can be adjusted or replaced to make the machine fit for components of multifarious small gears and steel shafts with different length and diameter. Each module of the machine is introduced in detail and related problems are discussed in the paper.

Abstract: The popular international and Chinese electromagnetic radiation protection standards are introduced, including the ICNIRP guidelines constituted by the International Commission on Non-Ionizing Radiation Protection, the EN62233 standards established by the European Committee for Electrotechnical Standardization and the GB 8702-88 regulations constituted by Ministry of Environmental Protection of the People’s Republic of China, etc. The situation of the light industrial equipments electromagnetic radiation has been tested and analyzed: the power of the induction heater is often up to thousands kilowatts, and there are many electrical control components and many dense circuitries in light industrial equipments. Their complicated electromagnetic fields release continuously electromagnetic waves and engender electromagnetic radiations to the surrounding environment. And, Chinese electromagnetic radiation protection standards lack limits for band less than 100 KHz (except 50Hz). It makes the electromagnetic radiation assessment of light industrial equipments lack sufficient basis. The electromagnetic radiation protection standard of light industrial equipments was discussed and the limits for electromagnetic radiation protection of light industrial equipments are suggested.

Abstract: On Labview’s development platform, taking full advantage of multithreading management and data stream control, a quick-responding dynamometer system for cutting process is designed and developed based on the Usb interface. The system possesses functions such as data acquisition, signal generation, signal pre-processing, data storage and data analysis, has facile operation interface, and supports data post-processing and analysis well.

Abstract: The grinding for cylindrical cam’s groove means grinding for groove’s flanks. For cylindrical cam with translating cylindrical followers, an auto-programming system for NC machining of cylindrical cam’s groove is developed. It can be applied to machine cylindrical cam with different types of curve grooves, by using cutter or wheel with different diameter. For validating geometry precision of the auto-programming system, emulation is carried out using the VERICUT, which is a NC machining emulator system. It is showed by the results of the emulation, there is excess of geometry error at bottom of groove when following situations are met: big pressure angle, high precision requirement and big diameter difference between wheel and roller. An important origin of such excess is computational error introduced by the auto-programming system in calculating the coordinates of wheel center.

Abstract: The different uses of NC grinding machine with ganged revolving spindle and the requirements to NC grinding machine for several special uses are discussed. A multifunctional three axes ganged NC grinding machine with patent right is introduced. Its ganged revolving spindle is changeable. Therefore it can meet the requirements of different uses. When the ganged revolving spindle works as headstock spindle, the NC grinding machine can be used for machining cylindrical cam, plate cam, noncircular shaft and so on. When the ganged revolving spindle works as a revolving spindle of dresser, the NC grinding machine can be used for dressing form wheels with multifarious curved generatrices accurately. With simple mechanism, wide flexibility and simple NC programming, it is especially fit for laboratory use. A new-style NC dresser with invention patent right is also introduced.

Abstract: In grinding of grooved cam, the programming for NC machining can’t directly be accomplished according to track curve of roller center in working drawing because the diameter of wheel becomes smaller than diameter of cam’s follower roller after wheel dressing. Track curves of wheel center are equidistant curves of the track curve of roller center and they can be gained by equidistant offset. But track curves of wheel center can’t be gained by equidistant offset for grooved cam with discretional plane curve profile, due to the profile including aspheric curves whose equations are usually unknown. To solve above problem, circular arc approximation for the aspheric curve part was realized by using Approximate Double Circular Arc Interpolated Method (ADCAIM), then equidistant offset of circular arcs was carried out by “offset” way, and consequently track curves designed for wheel center of any diameter can expediently be gained on AutoCAD platform. Validation experiment of simulation grinding was fulfilled on a NC milling machine. The experiment results indicate: it is feasible to NC grind grooved cam with discretional plane curve profile using the method introduced in this paper for the example.

Abstract: Approximate Double Circular Arc Interpolated Method (ADCAIM) has been proposed by the authors. It requires only the included angles in the normal directions of the adjacent arcs at intersection points to be less than specified value, but does not require the adjacent arcs to be tangent as in other circular arc interpolated methods. ADCAIM is an approximate method with better calculating speed because of its concise calculation, and its interpolated error can meet the requirement too. The problems in NC programming of aspheric curves have been solved by using ADCAIM. In this paper, to the plane profile including aspheric curves, using VB program language as the second development tool, auto-programming for NC machining of aspheric curve is also realized by using ADCAIM, as long as the curve’s profile graphics on the AutoCAD is known. The research result indicates: the method introduced in this paper can meet the needs of NC machining in both interpolated accuracy and calculating speed for the example.

Abstract: By applying NC system with three axes ganged function to M1432 universal cylindrical grinding machine, a NC grinding machine with two moving axes and one circumrotating axis ganged function is designed and developed. Besides two moving axes ganged function, this machine has a special function of driving the form wheel dresser to circumrotate around the Y axis. Ordinary grinding machine with two axes ganged function can’t machine complicated parts such as seaming roll with steep gradient groove. But a grinding machine with this special unction can do this by precisely dressing the form wheel with various aspheric curves. With the set-in PLC function of NUM1020 NC system and the correlative parameters to be respectively setup, the new machine can be used to machine some complicated parts such as seaming roll. The system receives machining process codes which is pretreated by computer firstly and dresses the form wheel in DNC mode, then machines parts with the form wheel later.

Abstract: The profile accuracy of the workpiece is mainly determined by the accuracy of abrasive wheel in the form-grinding process. Thus, the shaped wheel dressing becomes one of the key points in the form-grinding process. In order to grind the revolving curved surfaces grooves whose cross-sectional profiles are steep and smooth, a new NC dresser with three NC axes is developed by adding a swing axis on the basis of NC external cylindrical grinding machine. A wheel of any desired convex profile can be dressed when using the Diaform single-diamond dresser and the possible geometrical interference between the single-diamond dresser and wheel can be eliminated. By analyzing the influence of installation accuracy on the profile accuracy, a method of comprehensive error compensation is presented. The comprehensive errors can be diminished greatly to improve the profile accuracy by means of error compensation. It is proved in the experiments that the precision requirements of grinding the formed surfaces grooves can be met.