Abstract: A coordinate measuring machine comprises a base (1), a portal (3), a rigid cross member (13) associated with posts (4, 5) of the portal (3), a mechanisms (14) for placement of the portal (3) interacting with the member (13), a measuring system of displacement of the portal (3), having a measurement scale (8) and a measuring head (10) coupled with the member (13), and a post 7 for arrangement of the measuring system of displacement of the portal (3), mounted on the base (1) equidistant from the posts (4, 5) of the portal (3). The post (7) carries the scale (8) in a manner that the straight line, which is the extension of the longitudinal axis of the scale (8), crosses the measurement zone embraced by the portal (3).

Abstract: A piezoelectric resonant contact sensor includes an enclosure representing a hollow body of revolution and housing a piezoelectric vibration exciter disposed in a manner providing an acoustic contact. The shape of the exciter is selected to suit the shape of the enclosure. The enclosure accommodates at least two rods with contact lugs which are located so that their axes are perpendicular to the surface of the enclosure. The piezoelectric exciter forms a common oscillatory system in conjunction with the enclosure, the rods and the contact lugs. In the common oscillatory system oscillation frequency of the enclosure with the rods and the contact lugs is equal to the oscillation frequency of a sine-wave electrical signal fed to an exciting electrode of the piezoelectric vibration exciter.