摘要 |
A hinge probe is described in which a plurality of plates (4, 10, 45, 46, 47) are stacked in the direction of the probe axis (11). The plates are connected together in pairs by hinge means (12, 50, 52 and 53) (various forms of which are described) which define pivot axes and which constrain each pair of plates for relative pivoting movement about a side edge of the pair. The pivot axes are arranged to be mutually orthogonal to enable tilting of a stylus (2) (attached to one of the plates (4)) in any direction by pivoting of one or more of the plates when a force is applied to the stylus. An axial rest position for each movable plate on an adjacent plate is defined in combination with the hinge by a further support (14, 16) disposed between each pair of plates on the opposite side of the probe axis (11) to the respective pivot axis. A spring (17) urges the plates into their respective rest positions. Constraint against relative transverse movements of the plates of a pair is provided (in addition to that provided by the hinge if any) by a planar spring (20) (or other devices). Thus the hinge can be made quite flexible while maintaining an accurate rest position for the stylus to which it returns when any tilting force has been removed, and the force required to remove the stylus from its rest position is minimised. |