Abstract
Grease lubrication hypoid gear motor has been requesting to realize universal mountings. Hypoid gear is apt to arise scoring failure on tooth surfaces. Then, hypoid gear temperature rise was measured by using complete grease lubricated gear motor that was composed of two-stage reduction, in which high-speed stage was hypoid gear pair and low stage helical gear. Hypoid pinion was manufactured on motor shaft end. Motor rating was 0.75kW and rotation speed 1800r/min. Hypoid gear dimensions were tooth number 4 and 39 of driver and follower respectively, pinion offset 15mm, carbonized heat treatment. Lubricants were NLGI 000 alicyclic urea grease, NLGI 00 lithium soap grease, and ISO VG 200 hypoid gear oil to clarify characteristics of grease lubrication. Maximum temperature rise of grease lubrication was 73.4K at hypoid gear tip. Temperature rise ratio of grease to hypoid gear oil was nearly 1.2 for NLGI 000 grease, however varied from 0.9 to 1.7 for NLGI 00 grease. Right angle hypoid-helical gear motors of rating 0.1 to 2.2kW lubricated by NLGI 000 alicyclic urea grease were finally developed and now are on the market.
