| 摘要 |
1,118,561. Mandre's; cores. ASSOCIATED ENGINEERING Ltd. 20 July, 1965 [22 July, 1964], No. 29616/64. Headings B3B and B3F. A tubular workpieee holder comprises two axially-spaced sets of radial inextensible supporting members 10b, 11b, Fig. 3, urged apart by resilient means 12. A piston 1 is adapted for use with the holder by the provision of two axially-spaced conical surfaces 3, 4. The piston-pin bosses engage the sides of the central part of the holder to prevent rotation and a fixed pin 8a engages the underside of the piston crown to provide for axial positioning. In use, the holder may be stationary or rotated, being held axially by a centre 17. The piston may be machined simultaneously by two, three or more tools spaced equi-angularly. In a modification, the piston has two shoulders 3a, 4a, Fig. 4, and the supporting members 10b, 11b are tapered. In a further modification, the piston is located axially by supports at two points 5a, Fig. 8, the supports being pivoted on an axis 22. Casting.-A core for casting the piston is constructed of four sections surrounding a rectangular wedge-shaped centre-piece. The conical surfaces are turned in a lathe. |
