HOURGLASS WORM GEAR

• Main Authors: KAWADA HIROSHI, SONOHARA TSUNETOSHI, GUNHARA HIROSHI, SHIMAJI SHIGEYUKI, TOMITA NOBUYUKI, KOBAYASHI TATSU
• Format: Patent
• Language: English
• Published: 02.10.1991
• Subjects: BLASTING; ENGINEERING ELEMENTS AND UNITS; GEARING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HEATING; LIGHTING; MACHINE TOOLS; MAKING GEARS OR TOOTHED RACKS; MECHANICAL ENGINEERING; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; THERMAL INSULATION IN GENERAL; TRANSPORTING; WEAPONS

PURPOSE:To secure high performance as well as to prevent contact configuration from deteriorating at the time of loading, and also prevent an effective tooth contact area from being reduced by making a curved surface the tooth surface of a worm gear wherein the curved surface is created by a tooth surface grinding stone the surface of which is provided with an involute thread face. CONSTITUTION:Terms shown in the figure are coded as follows: hourglass worm gear shaft A1, worm wheel shaft A2, tool shaft A3, tooth surface grinding stone shaft A, hourglass worm gear angular velocity omega1, worm wheel angular velocity omega2, tool angular velocity omega3 and involute base circle radius rg. A curved surface created by a tooth surface grinding stone the surface of which is provided with an involute thread face, is made to be the worm tooth surface of a hourglass worm gear. On the other hand, a worm wheel is created by a hob the base curved surface of which is a tooth surface identical to the aforesaid worm tooth surface. As a result, the range of an effective mating surface is widened so that loading capacity is thereby enhanced. In addition, the angle formed by a concurrent contact line and relative velocity is enlarged, a lubricating oil film is thickened, and high efficiency can thereby be secured.