| 摘要 |
1,222,261. Boring heads. BABCOCK & WILLCOX CO. 16 April, 1968 [14 April, 1967], No. 17778/68. Heading B3C. A boring head comprises a base 10, Fig. 1, a liner 12 rotatably mounted in the base, a boring bar 33 rotatably mounted in the liner about an axis which is eccentric to the axis of the bore 11 of the base, means 31 for rotating the liner and boring bar, and means 56 for rotating the boring bar relative to the liner so as to vary the cutting diameter of tool T, oil pressure pockets 20-23, 35, 36 and 43, 44, having restrictors R, being provided between the running surfaces. Rotating means 31 comprises a grooved belt, or in a modification, comprises spur gears, or a chain. Means 56 comprises a rotary cylinder fixed to a drive housing 30 screwed to liner 12, and a rotary shaft 51 with a slide block 52 fixed thereto, which co-operates with a groove in the end 37 of boring bar 33. In a modification, an insert 72 is keyed at 73 to the base 70, Fig. 6, liner 74 is rotatably mounted in the insert, and boring bar 81 is rotatably mounted for eccentric adjustment in the liner, and has a thrust flange 84 integral therewith. The relative angular positions of boring bar 81 and liner 74 are produced by a rotary hydraulic motor 122, and a belt drive 124a, respectively. In a further modification, Fig. 9, boring bar 132 and liner 131 are rotatable relative to each other, and axially movable together in base 130, the rotation being provided by a gear 139 which co-operates with a splined rotary member 140, and the axial movement being provided by a cylinder 136. |
