牙醫手持鑽機性能檢測平台之設計與開發

Design and Development of Dynamic Measuring Device for Air Turbine Cartridge of Dental Handpiece

柯彥旭(Yen-Hsu Ko)

指導教授 ： 黃光裕

國立臺灣大學/工學院/機械工程學研究所/碩士(2007年)

https://doi.org/10.6342/NTU.2007.00446

摘要

轉速與扭力矩是判斷牙醫手機性能的基本量測項目，其輸出功率也受到牙醫手機操作條件如供氣壓力和鑽削軸向力之影響，由所獲得之扭力矩和轉速關係可以作為設計開發評估和品管之依據。本論文提出了數種牙醫手機性能量測系統之概念構想，最後依據牙醫手機操作方式，設計開發了能同步量測高速牙醫手機氣渦輪筒匣轉速、扭力矩與軸向負荷等之性能量測平台。性能量測平台由磨塊、導引簧片與應變規組成，藉由量測牙醫手機鑽削磨塊過程中導引簧片的應變，達到扭力矩與軸向負荷量測的目的，轉速則使用霍爾元件與光電感測元件兩種方式量測。在量測系統探討上採用有限元素軟體分析導引簧片在量測時的應力分佈，以確保導引簧片的負荷承載能力與量測性能，並分析探討扭力矩與軸向負荷量測之間交互干擾。實驗結果得知牙醫手機使用時的轉速變化率與供氣壓力無關，而與車針轉動慣量、鑽削時間以及扭力矩對轉速曲線斜率有關。輸出功率與轉速的關係曲線顯示牙醫手機的最大功率發生在空負載轉速的40％∼50％間。

關鍵字

高速牙醫手機 ； 扭力矩 ； 轉速 ； 功率 ； 量測 ； 感測器

並列摘要

This thesis describes the dynamic measuring device which designed and developed to measure the torque, speed, and drilling load of the dental air turbine Cartridge of the handpieces. Speed and Torque are the main measuring items for determining the performance of a dental handpiece, whose output power is also influenced by the operational conditions such as the supply pressure and the drilling force. The derived relationship between torque and speed can be applied as the evaluation basis in the design and development and the quality control. The dynamic measuring device is composed of the blocking cylinder, spring guides, and strain gages. The linear and torsional spring guides realize precision guiding for drill motion of the handpieces. The blocking cylinder provides the braking torque to affect the rotation motion of the air turbine cartridge. The torque and force sensors integrated in the spring guides measure the torque and the drilling force, and the speed sensor measures simultaneously the turbine speed. For studying the performance of the developed measurement system, the finite-element analytical software is used to analyze the stress distributions inside all acting spring guides for verifying their loading and measuring capabilities. Furthermore, the cross interference between the torque and the drilling force is also analytically and experimentally investigated. Based on the experimental results, we have found that the variation of the handpieces speed is affected by the moment of inertia of the test drill, the time of drilling, and the slop of the torque/speed curve, but not by the gas pressure applied to the handpieces. The maximum power occurs in the range of the 40 to 50 percent of the free running
speed.

並列關鍵字

High-speed dental handpiece ； Torque ； Speed ； Power ； Measurement ； Sensor

參考文獻

[1] Dyson, J. E. and Darvell, B. W., “Torque, power and efficiency characterization of dental air turbinehandpieces”, J. Dent., Vol. 27(7), 1999, pp.573-586.

[5] Brockhurst, P. J. and Shams, R., “Dynamic measurement of the torque-speed characteristics of dental high speed air turbine handpieces”, Aust. Dent. J., Vol. 39(1), 1994, pp.33-38.

[6] Dyson, J. E. and Darvell, B. W., “Dental air turbine handpiece performance testing”, Aust. Dent. J., Vol. 40(5), 1995, pp.330-338.

[7] Ernest, O. D., “Measurement systems application and design”, McGRAW-HILL International editions, fifth edition.

[8] Dyson, J. E. and Darvell, B. W., “Flow and free running speed characterization of dental air turbine handpieces”, J. Dent., Vol. 27(2), 1999, pp.465–477.