Turning tool teeth characteristic angle measuring appts. - has two pivoting cylindrical axes with apparent intersection point

摘要

The appts. measures the angles of cut, relief and skew of the teeth of a turning tool with removal of shavings. It has a stand with a vertical cylindrical axis pivoted at its centre. The upper part of the axis is reduced to a semi-cylinder. A bore, made in the vertical face thus obtained receives a horizontal cylindrical axis. This axis is also reduced to a semi-cylinder at its end, one of the faces thus obtained being positioned w.r.t. the vertical axis by a screw such that this face is exactly in the centre of the vertical axis pivot. The intersection point of the pivot centres of the two axes is thus an apparent point which may be put in contact with the teeth to be measured. The angular position of the two axes are measured by means of gradations an the stand and vertical axis. Two shafts are fixed on the stand, on which slides a bar supporting a threaded rod on which turns a small support stage on which the tool is placed. The point of the tooth to be measured is brought in contact with the 90 degree notch in the vertical axis formed by the plane of a semi-cylinder and its end. The contact of the notch face with the tooth face gives the angle of cut, and finally of skew. The contact of the notch face with the back of the tooth gives the angle of relief.