GB146461A - Improvements in adjustable reaming tools - Google Patents

Abstract

146,461. Schumacher, H. July 8, 1919, [Convention date]. Reamers; cutter-bars.-In an adjustable reamer or boring head for cylindrical work designed to avoid chattering a plurality of spring- pressed blades 6 are attached to double-armed levers 8 pivoted at 9 to bolts 10 secured by detachable pins 11 to the body 4 of the tool. The free ends of the levers have screws 14 which mav be adjusted according to the diameter required. A sleeve 15 on the tool spindle carries the pivots 17 of a number of rods 18 guided between pairs of rollers 19, 20 on the reamer body. On turning the sleeve by means of a handle 16 the rods assume a radial position and coact with lateral arms 21 on the levers 8 to lift the blades clear of the work on completion of the operation. In a modification the sleeve 15 carries a toothed rim engaging a number of bolts passing through the reamer body. The central portion of these bolts is eccentric and supports small thrust bolts, the other ends of which bear against the adjusting screws 14. The Specification as open to inspection under Sect. 91 (3) (a) comprises also a further modification, Fig. 5 (Cancelled), suitable for large motor cylinder bores and in which alternate blades are replaced by wooden centring-blocks 50 controlled independently of the blades. The sleeve 15 is replaced by two loose toothed rings 32, 51 and one of the eccentric bolts 24 is carried by a shaft 23 the upper end of which has an arm 60 carrying a conical roller 61. When the blades reach the cylinder-head, the roller contacting with the edge 62 of the cylinder causes the arm 60 to swing, thus rotating the shaft 23 and the ring 32 to withdraw the blades. The centring-blocks are similarly adjusted by the bolts 53, one of which is carried by a shaft 52 adjustable by a nut 54 and held in the required position by a suitable locking-device. This subject-matter does not appear in the Specification as accepted..