Patent GB-873132-A (GB)
Title: Improvements in polishing or like apparatus for operating on the bores of tubes and the like
IPC: B24B33/08
Filed: 1957-06-13
Abstract: 873,132. Polishing. CHAFFEY, S. J. June 12, 1958 [June 13, 1957; July 17, 1957], Nos. 18635/57 and 22581/57. Class 60. Polishing or like apparatus for use in the bore of a tube comprises a rigid body adapted to be supported in its operative position in the tube and having a fluid pressure receiving cavity adopted to be connected to a source of fluid pressure supply and at least three slots angularly spaced apart about an axis extending through the body and corresponding with the longitudinal axis of the bore of the tube, and said slots communicating at their inner ends with the cavity and at their outer ends opening on to the exterior of the body and being adapted each to receive and support a cutting element in a manner enclosing said element to be moved outwardly in the slot into contact with the bore of the tube and inwardly in the slot under the influence of fluid pressure and release thereof respectively. The body 10, Figs. 2 and 3, is connected to a hollow driving spindle 17 by an adaptor 13 having passages 18 through which fluid pressure can pass from the bore of the spindle 17 to a cavity 19 in the body 10. Slots 21 extend through the wall of the body and communicate at at their inner ends with the cavity 19. In each slot 21 is housed a piston comprising a flat rigid metal head plate 24 to which is secured a flexible cup member 25, e.g. of rubber, with a skirt 26. Abutting against the plate 24 is a holder 27 having a shallow groove in which is secured by adhesive a honing stone 29: Circlips 33 in circumferential grooves 32 in the body 10 engage grooves in the holders 27 so as to urge the honing stones 29 radially inwardly to inoperative positions, inward movement being limited by engagement of the skirts 26 of the pistons with the exterior of a helical coil 34. Vent holes 36 connect the cavity 19 with longitudinal flutes 35 in the body 10 to permit egress of oil from the cavity to the exterior of the body for lubricating and cooling. In use, the body 10 is inserted into the bore of a tube to be polished, the tube and body 10 are relatively rotated, preferably by rotating the spindle 17, and oil under pressure is fed into the spindle 17 to urge the honing stones 29 outwardly into contact with the bore of the tube; the tube and body 10 are relatively reciprocated, e.g. by reciprocating the body 10. Lubricant and coolant liquid may be passed through the bore of the tube additionally to, or instead of, that passing through the vent holes 36. In a modification, no holder is employed, the honing stone abutting directly on to the face of the piston, and being impregnated with lacquer to diminish abrasive action on the sides of the slots. In a modification, no pistons are employed, fluid pressure acting directly on the honing stones which are impregnated with lacquer. In a modification, Fig. 6, the honing stones 29 secured by adhesive to holders 27, are moved outwardly by a resilient bag 37, e.g. of rubber, located in the cavity 19. The holders may be omitted; and three honing stones may be used.