GB577294A - Improvements in and relating to measuring gauges - Google Patents

Abstract

577,294. Fluid-pressure servomotorcontrol systems. SOLEX, Ltd., WATTEBOT, L. E., and TAYLOR, J. W. April 15, 1944, No. 7000. [Class 135] [Also in Group XIX] In a gauge of the type comprising a nozzle or nozzles in connection with a source of pressure fluid and functioning by the indicated variation in pressure or rate of leakage flow from the nozzle or nozzles as set forth in Specifications 341,365, 348,860, 367,700, 388,265, 508,828 and 555,802, [all in Group XIX], a thin resilient and flexible plate of impervious material, preferably metal, of definite thickness, is mounted in front of the orifice of each nozzle and has a plane contact-making surface for co-operation with the part to be measured. In an embodiment for measuring, for example, the thickness of a rack 9, Fig. 2, a thin metal plate 11 is pressed by springs 15 against the upper surfaces of the rack teeth, thus bridging the grooves and enabling true measurement by the nozzle 8. Rotation of a nut 18 lifts the rods 13 and the attached plate 11 clear of the workpiece, as required. In an embodiment for measuring the external diameter of a circular toothed or splined object 32, Fig. 4, the thin metal plate takes the form of a sleeve 26, with a gap 33, spring urged against the workpiece and cooperating with nozzles 30. Means may be provided for opening the gap 33 to expand the sleeve 26, as necessary. In an embodiment for measuring the internal diameter of, for example, a rifle barrel, a thin sleeve 58, Fig. 7, is pressed against the internal surface by passing compressed air through circumferential tubes 59. A reading is then taken in the normal way by passing air through the nozzles 55. In another embodiment of the gauge for measuring internal diameters, solid rubber rings replace the inflatable rings, and screw means are provided for squeezing the sides of the rings to press the thin sleeve against the internal surface to be gauged.