Dispensing Simulation Analysis And Experimental Research On Precision Progressive Screw Dispensing Pump

With the vigorous development of the microelectronics packaging industry,microelectronics packaging technology is endowed with higher technicalrequirements, such as encapsulation products overall size smaller, higher intensity andmechanical electrical connection performance more outstanding, more durable servicelife of the product. As the key technology of microelectronics packaging technology,dispensing technology, must approach correspondingly driving way more accurate,response frequency more rapidly, single points more accurate, and adhesive repeatprecision higher consistency and other technical requirements. On the market atpresent most of the dispensing products has been difficult to meet these requirements,and contact precision screw dispensing pump as a new dispensing product, with itspoint of high accuracy and good repetition of consistency, and the advantages of wideapplicable medium, has been increasingly gaining attention. At present, this newproduct is still monopolized by foreign technology.Therefore, study of contactprecision screw dispensing pump is particularly important. This article makes itsstudy and experimental research from the following several aspects of contactprecision screw dispensing pump and its dispensing mechanism.First of all, in this paper, the common dispensing technology in domestic andabroad and the corresponding products are introduced and the advantages anddisadvantages of the products have been analyzed in detail, emphatically the analysisof the contact precision screw dispensing pump principle, advantages and researchstatus then this part indicates the research direction and research content of this article.Precision screw dispensing pump are analyzed in detail for the basic process of thedispensing operations and basic working principle, the core components of precisionscrew dispensing pump rotor and stat for their curve equation, sealing mechanism,and the accuracy in the working process. This paper proposes the influences andcauses in dispensing accuracy factors in precision screw dispensing pump. Accordingto the actual working condition, this paper designs a set of rotor and its stat, and three-dimensions modeling and assembly verification using CATIA, to ensure the feasibilityof design and processing; within the cross section in the working parts of the rotor andits stat, this paper analyzes the fluid flow mechanism in seal area for rotor and its statof the finite element simulation with FLUENT, and further studies of the influencelaw of dispensing accuracy with the rotor speed, fluid viscosity, and rotor and its statcoordinate of precision progressive screw dispensing pump.Secondly, this paper analyzes the precision screw dispensing pump for thestructure and motion principle as well as stress analysis of the rotor and its stat, it isconcluded that the force of the rotor under the actual working condition. Based on that,this paper chooses appropriate bearing and flexible shaft for precision progressivescrew dispensing pump, to ensure the design feasibility of mechanics; then designs and constructs the precision progressive screw dispensing pump prototype.For DCmicro-motor, precision gear box of a precise screw dispensing pump drive system thispaper makes the further research and expounds the structure of both as well as analyzethe influence factors of efficiency related to the speed of DC micro-motor, precisiongear box, electric current, no-load back gap characteristic, the motor output shafttorque and rotational speed. This paper sets up the whole dispensing system, andanalyzes all the parts of the building system.Moreover, precision progressive screw dispensing pump is analyzed in detail tothe requirement of control circuit, the paper designs and analyzes the current speed ofthe double closed loop control circuit working principle and process;The paperinstructs incremental encoder structure and working principle and customizes the rightmotor drive; further more the precise screw dispensing pump controller is designed,with its various parts detailed instruction.Finally, according to the experiment requirement this paper builds a completeprecision progressive screw dispensing pump experiment platform,tests theperformance of the pump from liquid viscosity, the angle of motor speed and supplypressure into precision progressive screw dispensing, as well as analyze these factorshow to affect the performance of dispensing laws. Performance is obtained underexperimental conditions by testing precision progressive screw dispensing pump forprototype on both ends of the motor under the condition of voltage24v, the prototypecompletes a dispensing period of158ms for the shortest, applying glue solutionviscosity from10poise to500poise, minimum amount of0.0163ml, dispensingconsistency control error within±1.2%. Through the experimental results verifiesthe feasibility of the prototype.