GB574041A - Improvements in valve seat grinding tools - Google Patents

Abstract

574,041. Grinding valve seats. DEHN, F. B. (Hall Mfg. Co.). Dec. 24, 1943, No. 21660. [Class 60] An eccentric valve seat grinding-tool comprises a stationary sleeve adapted to be mounted on a pilot stem, and carrying an encircling grinding-wheel spindle rotatable on its axis, and movable on a mount in a path eccentric to the sleeve. The valve seat 2 to be ground has an associated valve stem guide 4, in which is mounted a pilot stem 3, and adapted to be mounted on the stem is a sleeve 15 screwed at its upper end into a bushing 14 mounted in an opening 11 in a housing 10, the housing also having a lower and larger diameter opening 12 concentric with the opening 11. The sleeve receives an internal screwed depth gauge stem 16 and carries rotatably an eccentric sleeve 17, supported between a flange 18 and a gasket 19 and carrying at its upper end a spiral gear 21 ; the sleeve also has rotatably mounted thereon, on ball bearings 24, a hollow spindle 23 having screwed on its lower projecting end the hub sleeve 31 of a grinding-wheel 30. The sleeve 17 and spindle 23 are driven by a flexible shaft 35 connected to a shaft 37 in the housing 10, the shaft 37 having thereon a spur gear 38 driving a gear 39 on the spindle 23, and a worm 40 driving, through a countershaft, the gear 21; the grinding-wheel thus rotates at high speed and is moved slowly in an eccentric path around the seat 2. The depth gauge stem 16 and the stem 3 are connected together by a rod 46 screwed into the stem 16 and having a head 47 at its lower end adapted to be turned by a wrench etc.; the head is engaged by a washer 51 acted on by a spring 50 located in a nut 48 screwed on the stem 3 against a collet 49, so that the pilot stem 3 may be handled as a unit with the grinding-machine.