GB563219A - An instrument for gauging and recording the degree of accuracy or inaccuracy of a square or angular object - Google Patents

Abstract

563,219. Angles, measuring. HARDING, E., and CORRIGAN, J. J. March 28, 1943, No. 1435. [Class 97 (iii)] A device for testing the accuracy of a square or of an angular object is pivotally mounted so that the amount of turning movement imparted to the device indicates the amount of inaccuracy. As shown, the device comprises a triangle which is pivotally mounted at a point E on the line from the apex perpendicular to the base in a bracket B secured to a base C adapted to rest on a surface plate. Precision rollers D, D<1>, D<2> are adapted to be mounted in grooves a3 at the angles of the triangle and the base of the triangle is provided with a groove a<4> for locating members adapted to carry test bars and the like. The pivot of the triangle A comprises a spindle F, one end of which is provided with a flange f seating in a recess in a cap G and provided with an eccentric boss f<2> and a flat portion f<1> against which bears a piece g secured to the cap G. The bracket B is carried on the spindle F by means of bushes b<1>, b<2> and the outer end of the spindle F has a screwed portion f<4> for a cap K, spring and friction washers H, j, j<1>, j<2> surrounding the spindle and seated in a recess b<3> in the bracket B. Fig. 8 shows a V-piece R secured to the base of the triangle and has a test bar S clamped to the piece R upon which test bar is mounted a bevel gear, the face angle, face position and general concentricity of which is to be tested.