No abstract

Almost all customers require gear motor manufacturers to develop low noise, low vibration and low cost gear motors. Low noise and low vibration gear motors can be accomplished only by using high precision gears. The traditional method of manufacturing high precision gears for general industries is to grind the teeth after gear cutting. However, recently, there is now a strong demand to increase productivity and reduce manufacturing cost by using only a hobbing machine. To content these requirements, it is believed that direct dry hobbing after gear material heat treatment is the best manufacturing method. First, 0.45% carbon steel of round gear material was hardened to HRC53-56 by high frequency induction heat treatment till the specified depth. Next, the high hardened material was directly hobbed by special carbide hob installed on a highly rigid CNC (Computer Numerical Control) hobbing machine without using cutting oils. In the other words, the authors have developed Direct Dry Hobbing of High hardened Material, called the RGC (Round bar Gear Cutting) Method. The gears applying the RGC Method were module 0.8 to 1.25 and of helix angle 25°. The gear profile accuracy was JIS Grade 1–2, which is comparable to AGMA Grade 11–12. Gear motors incorporating gears manufactured by the RGC Method have been launched into the market and are now receiving remarkable customers satisfaction as low noise and low vibration gear motors.

No abstract

Intelligent materials have been studied in various fields. In this study, Shape Memory Composite (SMC) is produced as one of those intelligent materials. SMC consists of Shape Memory Polymer (SMP) and Shape Memory Alloy (SMA). These two materials possess different characteristics in temperature changes. Therefore, we investigated the possibility of the SMC’s actuator function as an intelligent material. The actuator function is achieved by applying a current to SMA fiber of SMC to grab and release objects. As a result of this investigation, meaningful data for actuator to design SMC is obtained.

We clarified experimentally electrical and mechanical pruperties of SMA ( Shape MeIuory Alloy ) in diameter O． 2mm and SMP ( Shape Memory Pulymer ) in thickness 1． 工 5 mm ，正 n addition ， SMC ( Shape Mcmory Composite )composed of these SMA and SMP ， was also investigated to clarify the e 】 ectrical 且 nd mcchanical properties required to actuators ． 鍬工 aill results ohtained ill this study are as follows ； (1 )When SMA was heated elect ． rically over Q． 4A ， recovery time until the origina ］ 且 gure wasunder 5 s 巳¢ onds ．(2 ＞Wheu SMC was heated elec 亡 rically over O ． 3A ， the surface tcmpera 一 し ure of SMC re 且 ched approximatcly Tu after 120 seconds