| 摘要 |
Head for checking linear dimensions of workpieces comprising a support, a movable arm carrying a feeler adapted to touch the workpiece to be checked and three members substantially perpendicular to a longitudinal geometric axis of the head. One of the members is fixed to the support, another member carries the arm and the third member is intermediate to the first two members. Arranged between adjacent members are two pairs of balls, which are aligned along paralllel axes, glued to one member and housed in conical recesses obtained in the other member, and which define two axes for mutual rotation between the adjacent members and are always maintained into contact with the surfaces of the relevant conical recesses by means of springs. An electrical circuit, closed in rest conditions, comprises two pairs of electrical contacts, which open the circuit as a consequence of displacements of the movable arm along opposite directions or as a consequence of an axial displacement of the movable arm.
|
