| 摘要 |
1,068,786. Gear - cutting. GLEASON WORKS. June 17, 1965 [July 22, 1964], No. 25670/65. Headings B3B and B3L. [Also in Division F2] Oscillatory motion is transmitted to a driven member from a reciprocatory or oscillatory driving member through a positive flexible band drive and through a friction drive. As shown applied to a gear-generating machine of the type described in Specification 1,066,692, flexible steel bands 19, 21 are anchored to a sector 24 fast with a tool-carrying cradle 2 oscillatable about an axis 3 and to a slide 15 reciprocated on a guide 17 which is pivoted at an end 18 to the machine frame and is biased upwardly at its other end by a spring- loaded piston 64 to urge surfaces 59, 58 (Fig. 2, not shown), on the slide and on the sector into frictional engagement. The spring pressure can be adjusted by a screw and generally is such that the friction drive bears the major portion of the load, the bands serving to maintain the desired phase relation; if desired. the pressure may be reduced so that the friction drive bears a minor portion of the load and serves for damping oscillations or vibrations in the band drive. In a modification, the surfaces 58, 59 are omitted and the friction drive is by way of the surfaces of the sector and the slide and the bands. In this case, it is preferred to form a slight clearance between the surfaces of the sector and slide and the inner band 21 so that the friction drive is transmitted through the outer bands 19. The slide 15 is reciprocated with variable amplitude by a variable length lever arrangement 8-12 which is oscillated by a cam 7 on a driving shaft 1. The slide 15 is connected by a variable length lover arrangement 31-37 to a rod 30 which is thus reciprocated. The rod 30 is connected by a screw-andnut device 38, 39 with a shaft 41 which is thereby oscillated. The shaft 41 is geared to a side wheel 44 of a bevel planetary gear having a side wheel 46 geared to a work spindle 4. Indexing of the work spindle, to bring successive tooth slots of a work gear into cutting position, is effected by a mechanism 54 whose output shaft 55 carries bevel planetary gears 45. The mechanism 54, which may be hydraulically operated, is controlled by a valve 56 actuated by a cam 57 on the shaft 1. The valve 56 also supplies hydraulic pressure to retract the piston 64 against the pressure of its spring to disengage the friction drive. In a modification (Figs. 6 and 7, not shown), drive is transmitted from one oscillating sector to another by band and friction drives. |
