Research On Laser Drilling Machine For Oral Osmotic Tablets

The drilling requirements in the production of a new type troche, osmotic pump control-released tablets, is the nodus in the research of this kind of medicine. Therefore, the Laser Technology Institute of Tianjin brought forward to a tentative plan that making holes on oral osmotic tablets with carbon dioxide laser which was supported by Tianjin technique committee. According to the request of the project, a prototype of laser drilling system for osmotic tablets was designed and manufactured in about one year. This paper introduced the whole design method, the implement in technical way, the testing about the performance and precision parameters and also the feasibility of running in a long period.The laser drilling machine would be applied in industrialization production. Considering the applicability to multichamber osmotic tablets, a color identity system was utilized to distinguish the color of tablets. Through a mechanical barrier and a photoelectronic sensor, the drilling orientation was ensured. The drilling machine with a drilling pace about ten tablets per second included a dynamic vision system to inspect the tablets in order to make sure that the unqualified tablets would be totally rejected.The research work included:1. With the investigation in this field, analyzed the feasibility of drilling on osmotic tablets with carbon dioxide laser based on drilling principle. Confirmed the parameters of the laser used in this system according to the tablets provided.2. Designed the whole laser drilling system based on the requirements of drilling effect, including the mechanism design, controlling system design and the software design.3. Designed the on-line detection system and the elimination system with a color identity sensor and an intellectualized vision sensor, through which the real time scanning of the osmotic tablets and the rejection of the unqualified tablets were actualized, and also the qualified rate of the tablets produced was ensured.4. Expatiated on the demarcate experiments of precision and reliability of the laser drilling machine and finally analyzed the factors which resulted in the error of the machine and brought forward to the ameliorations of the system. A prototype of the laser drilling machine for oral osmotic tablets was excellently designed and manufactured finally. The prototype machine runs reliably and automatically with high speed which achieved making holes on osmotic tablets accurately. With proper amelioration, the machine can be used in mass production of osmotic tablets.The innovations of the paper were as follows:1. Chain-drive mechanism was adopted and elimination system which can reject single tablet was developed.2. Invention of the tablet distribution system which achieved a distributing rate as 99.99 percent.3. Utilization of the color identity pattern.4. Actualization of the orientation of transport plate with a photoelectronic sensor.5. Realized of the closed loop control of the drilling position with a self-made barrier.6. Application of the DVT dynamic scan.