GB783088A - Improvements in or relating to transmission gearing - Google Patents

Abstract

783,088. Hollow cutter-heads; rotary toolheads. CHILD, F. Feb. 8, 1954 [Feb. 26, 1953], No. 5357/53. Class 83 (3). [Also in Group XXIV] In a rotary tool-head, a tool-carrying slide 10, Fig. 2, mounted in an undercut diametralchannel on the face of the head 5 carries a rackbar 18 engaging a scroll on a plate 15 rotatable on the hub 6 of the head so that relative rotation between the head 5 and plate 15 effects a radial traverse of the slide 10. The plate 15 is secured to a sun-wheel 29 alongside which, and also rotatable on the hub 6, is an equal-diameter sun-wheel 32, having a few more teeth than the wheel 29, and an equal-diameter sun-wheel 34 having a few less teeth than the wheel 29, the wheel 34 rotating on the hub of the wheel 32. The three sun-wheels mesh simultaneously with a pinion 30 carried by a stationary plate 22. To effect inward or outward traverse of the slide 10 one or other of the wheels 32, 34 is coupled to a collar 20 fixed to the hub 6, the wheel 29 being then slowly rotated relatively to the hub 6 by the pinion 30. The coupling of the wheels 32 or 34 to the hub 6 is effected by insertion of a key 35 through one or other of two holes in the collar 20 into one of two holes, or rings of holes, in the two wheels. In a modification, the key 35 is spring-loaded and axially slidable in an eccentric, rotatable to bring the key opposite the holes in the desired sun-wheel. Alternatively, the key may be fixed on an axially-slidable spring- loaded eccentric. When the device is employed for boring only, without radial traverse, the plate 22 is released so that the gearing may rotate solidly. The tool may be rough-set by locking the appropriate wheel 32 or 34 to the hub 6 and checking the plate 22 by hand, a fine adjustment being made against a graduated dial, by a key in a hand-feed bevel-pinion 27 engaging teeth on the plate 15. Further sunwheels may be provided to effect radial-traverses at two or more speeds. In a modification, the scroll-plate 15, Fig. 4, is secured to an annular gear 58 driven by one or more planet-pinions 51 simultaneously engaging three sun-wheels 44, 46, 47. The planet-spindle 52 also carries a relatively-rotatable pinion 56 engaging a fourth sun-wheel 49 fixed to a stationary plate 22 and a driving annulus 57 fixed to the head 5, so that the spindle 52 continuously planetates about the common axis of the sun-wheels. The wheels 44, 49 have equal numbers of teeth, while the wheels 46, 47 have respectively a few more and a few less teeth. The wheels 46, 47 rotate respectively on the inner and outer peripheries of an annular rib on the fixed wheel 49, and a flat key 62 passing through radial slots in the stationary plate 22 and wheel 49 is radially movable, from a neutral position, to engage dog-teeth on either of the wheels 46, 47 so as to lock either wheel against rotation. The hub of wheel 44 is extended and geared to a handle 67. When the key 62 is in neutral, the wheels 46, 47 are free to rotate while the wheel 44 having the same number of teeth as the fixed wheel 49, is held stationary by friction in the gearing associated with the handle 67, so that the annulus 58 carrying the scroll-plate 15 is driven at the same speed as the annulus 57 on the body 5, and no automatic traverse of the slide 10 is obtained. The wheel 44 may, however, be rotated by the handle 67 to give an inward or outward manual traverse by causing a relative rotation between the body 5 and scroll-plate 15. For automatic inward or outward traverse, the key 62 is moved outwards or inwards respectively, to hold the wheel 47 or 46 respectively, stationary. The planetating-pinion 51 then loses or gains respectively in relation to the pinion 56 so that there is a slow relative rotation between the annuli 57, 58, i.e. between the body 5 and the scroll-plate 15.