To provide a structure which can inhibit a tip of a worm from moving in a radial direction perpendicular to a direction in which the tip moves close to or away from a worm wheel in a worm speed reducer in which the tip of the worm is biased to the worm wheel side.SOLUTION: A holder 21, in which a tip side bearing 20 fitted on a tip of a worm 18 is fitted, has a pair of inner spring holding parts 45 and an outer spring holding part 53. A plate spring 22 has: a substrate part 55 in which its radial outer surface contacts with the outer spring holding part 53; a pair of arm plate parts 56 which extends from both circumferential end parts of the substrate part 55 in a circumferential direction and in which their radial inner surfaces contact with the pair of inner spring holding parts 45; and a pair of curved plate parts 57 which is connected to tips of the pair of arm plate parts 56 and in which their radial outer surfaces elastically connect with a holder holding part 26 of a housing.SELECTED DRAWING: Figure 6
【課題】ウォームの先端部をウォームホイール側に付勢しているウォーム減速機において、ウォームの先端部がウォームホイールに対して遠近動する方向と直角な径方向に移動することを抑制できる構造を提供する。【解決手段】ウォーム18の先端部に外嵌された先端側軸受20を内嵌したホルダ21は、1対の内側ばね保持部45と、外側ばね保持部53とを有する。板ばね22は、径方向外側面を外側ばね保持部53に接触させた基板部55と、基板部55の周方向両端部から周方向に延出し、径方向内側面を1対の内側ばね保持部45に接触させた1対のアーム板部56と、1対のアーム板部56の先端部に接続され、径方向外側面をハウジングのホルダ保持部26に弾性的に接触させた1対の湾曲板部57を有する。【選択図】図6
WORM SPEED REDUCER AND ELECTRIC ASSIST DEVICE
ウォーム減速機及び電動アシスト装置
2020-12-03
Patent
Electronic Resource
Japanese