GB566567A - Apparatus for measuring movements, particularly for measuring the dimensions of workpieces or for comparing the dimensions of two or more workpieces - Google Patents

Abstract

566,567. Linear - dimension gauges. THOMAS, P. G. Nov. 25, 1942, No. 16753. [Class 106 (ii)] A gauge comprises a number of beams, means for deflecting these beams, a feeler carried by one of the beams, and means interconnecting the beams in such a manner that, after the deflection of the beam carrying the feeler has been stopped by the contact of the feeler with a work-piece, further deflection of another beam is utilised to furnish an indication concerning the required dimension. The gauge and body 1 is clamped to a column (not shown) adjacent a support for the work-piece (not shown). Two upper beams 7, 8 and two lower beams 9, 10 are secured to the body. A block 21 is secured to the lower beams 9, 10 and is connected to a barrel 17 by adjustable spring detents. The barrel is also held by detents carried on a bottom beam 20. The feeler member 41, 49 is screwed into and out of the barrel 17 by turning a knurled nose 48. A load transfer plate 16 bears through balls 50 on to the upper beams 7, 8 and through a ball 52 on to the barrel 17. The nose 14 of a micrometer 11 bears on a plunger 53 connected by springs (not seen in Fig. 1) to the load transfer plate 16. In use, a standard gauge piece is placed beneath the feeler 49 and the micrometer 11 operated to depress the plunger 53 and, through the springs, the load transfer plate 16, which in turn deflects the upper beams 7, 8 and, through the barrel 17, the lower beams 9, 10 and the bottom beam 20. When the feeler member 49 contacts the gauge piece, further movement of the barrel 17 and beams 9, 10, 20 is prohibited, but deflection of the upper beams 7, 8 continues until contacts 58, 60 carried by upper beams 7, 8 and lower beams 9, 10 respectively meet to give an audible signal to the operator. The reading of the micrometer 11 is noted, a work-piece substituted for the gauge piece and the operation repeated. The difference between the micrometer readings is an indication of the difference between the dimension of the gauge piece and the workpiece. In a modification, Fig. 5, the movement of the micrometer depresses the plunger 81 connected by springs 82 to the load transfer plate 76 bearing on the barrel 73 housing the feeler member 75. The load transfer plate 76 swings a lever 71 secured to a fixed rod 63 and thus stresses the rod torsionally. The barrel 73 is connected by detent means to a lever 72 secured to a fixed rod 64 which is stressed torsionally and also to a lever 73A pivoted to the body of the apparatus. The angular position of the normally fixed rods 63, 64 may be adjusted by adjusting carrier plates 65, 67 locked by screws 69, 70. The Provisional Specification describes also a modification in which a second micrometer, mounted on a lower beam element, has the feeler attachment carried by its measuring spindle.