GB786213A - Device for a dimensional inspection of mechanical parts - Google Patents

Abstract

786,213. Moulding test specimens. RAZDOW, A. March 9, 1955 [April 28, 1954], No. 6883/55. Class 87(2). [Also in Groups XIX and XXII] A number of casts 35 are formed in accordance with a number of parallel sections of a workpiece 5, and the profile of each cast is optically projected simultaneously with a master profile. The apparatus comprises a workpiece holder 9, 10 adapted to retain the workpiece 5 in position and a box 22 having a plurality of pin members 27 slidably disposed therein, advanced from and withdrawn into the box 22 by fluid pressure where by each pair of adjacent sets of pins forms in conjunction with the side walls of the box 22 a mould 33 and the front end of each pin engages closely the workpiece 5, the mould being fed with molten plastic from a heated reservoir to form a cast 35 therein. The workpiece holder 9, 10 together with the workpiece 5 is then withdrawn, each cast being then advanced and a master profile element 47 is projected on a screen 43 simultaneously with the advanced cast 35, thereby permitting the evaluation of any discrepancy between the profiles. A turbine blade or like workpiece 5 is held in a vice 9 on a slidable platform 4 and the box 22 is moveable vertically on a rod 21 by means of a screw 26. An abutment 16 adjusted to be opposite the projecting pins 27 ensures that the blade does not move during the casting process. The pins 27 are moved into and out of engagement with the blade by means of fluid pressure supplied by pipes 25 through ports 29, 31. A number of casts 35 are made simultaneously for different sections of the blade, and when the castings have cooled the platform 4 with the blade 5 is retracted, leaving the casts 35 projecting and uncovering the opening 2 through which passes the illumination for the optical system, Fig. 12. The pins 27 are withdrawn and cams 36 on a shaft 37 move the casts in turn into operative position in the optical system. Pin members may be projected on to each side of the blade simultaneously, one set replacing the abutment 16.