Patent GB-567411-A (GB)
Title: Improvements in and relating to tools for boring, milling or surfacing operations
IPC: B23Q1/48
Filed: 1943-07-23
Abstract: 567,411. Boring and facing heads ; chucks. JEARUM, F. C. July 23, 1943, No. 12030. [Class 83 (iii)] In a rotary tool head for boring, facing, milling, &c., a chuck carrying the tool is displaceable radially on the head by a scroll plate thereon, relative rotation between the scroll and the head in one direction or the other being caused by two sets of internal and external gears, whereof the internal gear of one set and the external gear of the other set are driven and the other gears are connected to the scroll, the external gears being radially displaceable to institute the appropriate drive. The tool chuck 1 is carried by a block 2 radially slidable on a body 4 connected to the driving spindle 5 and a toothed segment 6 on the block 2 engages a scroll 8 having a peripheral flange 10. The internal gear 44 is rotated within the flange 10 and the internal gear 153 is connected to the latter by pins 55, the external gear 40 associated with 44 being connected to the scroll by a pin and radial slot 51 and the external gear 47 associated with 153 being connected by a pin 46 to a radial slot in a driving ring 37 which is connected by a slot and lug 18 to a bush 16 keyed to the shank 5. The internal gear 44 is also connected to the ring 37 by a driving lug 50. The external gears 40, 47 are rotatable respectively on a flange of the ring 37 and on a plate 24 and are normally maintained in a position concentric with the head and out of mesh with the internal gears, by means of a pin 32 eccentrically mounted on a hub 26 which is rotatable by a handle 29 in a closing plate 19 of the head. The pin 32 enters slots 58 in the plate 24 and in a similar plate 23 lying within an annular recess 42 of the ring 37, the slots having straight chordal portions and an arcuate portion 59 at one end such that displacement of the pin 32 in one direction from the neutral position shown in Fig. 2 will move the plate 23 and gear 40 radially to rotate the scroll in one direction and displacement of the pin 32 in the other direction will move the plate 24 and gear 47 radially to give reverse rotation of the scroll. The neutral and driving positions of the hub 26 are determined by a spring detent 31. The plates 23, 24 are'guided in their radial movements by the flat sides 43 of a central aperture therein engaging the sides of a boss 22 on the closing plate 19 which is prevented from rotating with the head by a lever attached to the frame of the machine engaging a key 33 thereon. The lever incorporates a friction coupling so that it may yield and allow the plate 19 to rotate with the head if rotation of the scroll is impeded, or may be disconnected to allow hand actuation of the scroll. The handle 29 may be set in either driving position to cause the scroll to be rotated faster than the head by the gear 40 or slower than the head by the gear 153, the tool then being given a continuous radial feed in one direction or the other during rotation of the head, or the head may remain stationary and the tool be set in any required radial position by rotating the scroll by hand through its flange 10, vernier scales being provided on the flange and on a collar 60 angularly adjustable on the head. A nut 12 on a screwed collar 11 on the shank 5 may be used for disengaging the shank from its socket in the machine. Specification 561,975 is referred to.