| 摘要 |
1,083,045. Power driven wrench. TIMKEN ROLLER BEARING CO. June 4, 1965 [Oct. 19, 1964], No. 24032/65. Heading B3N. [Also in Division F2] A wheel bearing or like reverse drive wrench comprises an air motor 10, Fig. 1, a handle 13 having clockwise and counter clockwise control switches 14, 16 thereon, a clutch assembly 20, and a spanner portion 21. Clutch 20 comprises a housing 23, Fig. 2, having stepped walls 24, 26, Fig. 3, a sleeve 28 keyed to motor shaft 27, a spring 31 seated in a portion 29 of the sleeve, and a bush 32 rotatable in housing 23 and having ears 33 which co-operate with steps 24, 26 on the housing. In operation, a switch 7 is actuated by the operator pressing a plate- 8, switch 14 is depressed, and air motor 10 rotates shaft 27, sleeve 28, and spanner 21, to thus tighten a bearing. Bush 32 is rotated due to the frictional engagement of spring 31 with the bush, until ears 33 abut walls 24, 26. Shaft 27 continues to rotate sleeve 28, and wind up spring 31, until the bearing being tightened stalls motor 10. Switch 16 is depressed, shaft 27 rotates in an anticlockwise direction to thus unscrew the bearing, and spring 31 rotates bush 32 until ears 33 engage the opposite sides of walls 24, 26, the spring locks shaft 27, and motor 10 stalls. In a modification the spring clutch is replaced by a cam clutch 40, Figs. 4, 5 (not shown). Shaft 27 is keyed to wrench drive 41 and the inner race of the clutch is an interference fit on drive 41. The outer race has a key 43 which moves in an arcuate keyway (44) in housing (45). In operation, drive (41) is rotated and carries the inner and outer races in a clockwise direction until the outer race is stopped by key (43) engaging the end of keyway (44). The inner race continues to rotate until the motor stalls. Under counter clockwise movement to unscrew the bearing a required amount, the races rotate together until key (43) engages the opposite end of keyway (44), and the motor again stalls. In a further modification, Figs. 6, 8, the clutch assembly comprises a housing 50, having an end projection 50a, a sleeve 53 rotatable in the housing and having a dog 53a thereon, a cam clutch 63 having its outer race keyed to sleeve 53 at 65, and an end cover 58 having a stop 62 in the form of a pin, the cover being adjustable on the housing so as to vary the position of the pin relative to projection 50a. In operation during clockwise rotation the clutch rotates until dog 53a engages pin 62 and the bearing is tightened. The bearing is loosened during counterclockwise rotation until dog 53a abuts projection 50a and the motor stalls. |
