Advanced Materials Research Vols. 503-504

Abstract: After expounding the characteristic and the weakness of three-ring speed reducer, this paper pointed out the principle of two-ring speed reducer. In two-ring speed reducer, the planetary gear with inner teeth is supported by three shafts, and rotary centers of three eccentric shafts are made to form an equilateral triangle in a plane. At any time, meshing points of two internal gear pairs in two-ring speed reducer are always located at two symmetric points of the output rotation centers, which makes the manufacturing and assembly of two-ring speed reducer are more simple and convenient than three-ring one. Then, the force model of two-ring speed reducer was established, and the simulation analysis was done in Matlab. The result in the simulation coincides with in the finite element method, which testifies the formula deduced in this paper is correct.

Abstract: Copper wire bonding has obtained prevalent owning to its economic advantage and superior electrical property. However, the replacement of gold wire with copper wire introduces hardness related issues as copper is much harder than gold. This article reports investigations of the process optimization of ball bonding for 1.8mil copper wire. The results showed that the suitable ranges of the three key parameters were: contact force was 100~120gf, bond time was 15~25ms, and bond power was 100~110dac. When the input energy was too low, it was hard to get effective bonding. However, excessive input energy would cause chip crater and serious extrusion of metallization layer.

Abstract: In the process of rapid orientation device design for aquatic inserting piles, piles were fixed position using straight and steady function of the edge piles ahead. Piles were inserted to riverbed inside steel casing without horizontal current velocity. Three kinds of orientation schemes were put forward. To scientifically and accurately choose the best scheme, the evaluation index system was established in the way of expert's mark. The gray relation analysis method was adopted to analyze each scheme, synthesize each factor, and finally educe the optimal scheme.

Abstract: It is always hot and difficult to research kinematic forward solutions of the Parallel robots .In the paper according to the trait of 3-PRS parallel robot, the three freedom degrees are analyzed by using helix theory, which include one prismatic freedom degree along z axis and two rotation freedom degrees along and axis. The movement equation of the motion platform center is given on this basis, then the example is programmed by making use of Matlab software, in the end the kinematic forward solutions are gained. The method is in common use and is suitable for other type parallel robots. This also provides the reference value for control strategy

Abstract: Conventionally, the influence of guy wire and wind load on derrick was often ignored in the static strength analysis of derrick of truck-mounted workover rig, it does not accord with the actual working conditions. This paper made the finite element analysis for one derrick of Truck-mounted workover rig through ABAQUS software. The author derive the maximum static hock load which derrick can bear, and reasonably shorten projective radius of guy wire, under different static hock load and wind load, determining the weakest position of derrick. Truck-mounted workover rigs are widely used in the filed of workover and drilling operation, due to their characteristic of power maneuverability and convenient to use. Derrick is the mainly working part of workover rig, as well as the weak links of workover. In order to guarantee relatively high security performance, we should accurately make simulated calculation for carrying capacity of derrick in the process of designing. The author derive the maximum static hock load which derrick can bear, and reasonably shorten projective radius of guy wire, by using the ABAQUS FEM system, apply for statics analysis of derrick under different static hock load and wind load.

Abstract: The lemniscate type crane is fabricated by Figee B.V. of the Netherlands. There are great differences in outward appearance, geometric shape, luffing performance between lemniscate type crane and ordinary double-link type crane. Lemniscate type crane has some advantages, i.e. lower centre of weight, practical and reasonable structure, strongly anti-wind and easy operation. Based on inverse design and theory of mechanism, instant centers of velocity, luffing locus and moment of lemniscate type crane is studied and solved. The equations of kinematics and luffing moment are obtained.

Abstract: In order to improve the performance of automotive generator stator windings ,the paper design a method of automotive generator stator windings by two –three phases windings.This method reduce coil cross , shorten end connections and improve the thermal resistance of the generator.Meanwhile, this paper analyze magnetic field of stator windings by ansoft finite element analysis software,the armature magnetic field and its harmonic content are analyzed to verify the validity of this design.

Abstract: In order to save energy, decrease the loss and improve the technology level of high voltage flame proof three phrase asynchronous motor for fan, the condition, problem and development trend of the motor are studied in the paper. The motor structure, wind path system, electromagnetic scheme, insulation structure, electrical explosion-proof structure are improved, and non electric explosion-proof theory and low noise design are firstly applied in the research and development of motor. The efficiency of the motor is improved 2% by the method of optimizing the structure of motor and improving the making technology. The new motor not only has high efficiency and advanced and reliable structure, but also is safety in use, convenience in maintenance, has better social and economical benefits and better market prospect.

Abstract: In order to process the involute curve profile of scroll compressor，the method of using Archimedes spiral to approximate the involute curve in the polar coordinates is used.The error of approximation caused by different interval distances of interpolation points is simulated by Matlab.The machining experiment of orbit scroll using the appromation method of equal-radial- interval is carried out on CNC machine tool,and the interpolation error of actual machining is . The effectiveness and practicality of the method were tested and varified.

Abstract: Multi-point spraying air-conditioning room is widely used in some textile mills due to the advantage of no spray pipe and high power water pump. This article take the textile air-conditioning rooms as an example, comparing with the design of supply air system and result of experiment tests, the characteristics of multi-point spraying of air-conditioning system in supply air and heat and moisture exchange efficiency during actual operation are obtained. Besides, comparing with the wind pressure chart of the design of supply air system and result of experiment tests, it comes to a conclusion that Multi-point spraying air-conditioning room should be improved according to their own situation in actual operation. It also proposes the feasibility of wind pressure chart for regulate of supply air system.