GB588943A - Improvements in or relating to devices for forming trueing, reshaping or reconditioning valve seats - Google Patents

Abstract

588,943. Portable turning-apparatus. HOLLINSHEAD, P. C. Jan. 30, 1945, No. 2320. [Class 83 (iii)] Cutters.-A device for reconditioning valve seats comprises a head portion coned at one end to correspond with the conicity of the valve seat for engagement therewith, a depending pilot stem integral with or separate from and keyed or otherwise secured to the head, and made to slide in the bore of the valve spindle bush, a socket or slot in the head opening endwise into said coned surface, a cutting tool with a single cutting edge projecting from said coned surface, means for adjusting said cutting tool and for securing it in the slot, and means for imparting a rotary motion to the device relatively to the work under an axially directed force. The stem 4 of the device is arranged to be a sliding fit in the valve guide 5 and carries a head portion 2 with a guide surface 9 complementary to the seating in the engine or other work to be reconditioned. This guide surface which is preferably hardened is gapped at one place to accommodate a cutting tool 3 with an edge 12 which is guided in an oblique slot 11 in the head and is adjusted by a screw 13 and clamped by a set-screw 16. A tommy bar 10 passing through the head is used to rotate the tool and apply axial force for cutting a seating. The pilot stem may be detachable so that stems of different sizes to suit different guides may be used with the same head, and the tommy bar may also be part of an extension where the seating to be cut is sunk below the level of other parts of a cylinder block or the like. The work may be rotated, such as in a lathe, and the tool held stationary during cutting.