Abstract: A revolving fixture intended to support tools or instruments is described. Said fixture comprises first elements for the connection to a carrying structure, and second elements adapted to lock the said tool or instrument and rotatable relative to the said first elements about a main axis.The main feature of this fixture is to comprise means apt to adjust, in a relatively precise, responsive and stable manner, the position of the said tool or instrument with respect to the said axis, so as to position the tip of the said tool or instrument in such a manner as to make it substantially coincide with a point of the said main axis and thus minimize the deviations of the tip of the tool or instrument from the said main axis during the rotation of the said second elements relative to the said first elements.

Abstract: A connection unit for mounting a tool with precision and accuracy on a machine, particularly a measuring machine, but which at the same time does not provide a rigid connection between the tool and the machine so that if the tool undergoes accidental collision, it does not suffer damage, is described. The main feature of this connection unit is to comprise first and second members which can be fixed respectively to the machine and the tool, said first and second members being connected together by mutual positioning means, under the action of constraint means which allow a limited relative movement between said first and second members as a result of a displacement force exceeding a predetermined value and acting along directions and senses of movement allowed by said mutual positioning means.

Abstract: A tracer unit for use with measuring machines is described.The main feature of this tracer unit is to comprise a plurality of tracer tools, each of which is provided with a rod arranged to come into contact with a surface to be scanned, a movable body connected to said rod, a fixed body, first means which supply a first signal either when said movable body leaves the position of equilibrium relative to said fixed body or when said movable body passes through a determined position relative to said fixed body, and second means arranged to indicate from which of the various tracer tools said first signal is originated.

Abstract: A position transducer for machine tools and measuring machines, arranged to measure relative displacements of a first part of the machine with respect to a second part of the machine, is described. The main feature of this position transducer is to operate by means of the optical coupling of at least two photoelectric readers fixed on the first part and at least two optical photoengraved rules rigidly connected to the second part. Selector means are provided to present in output the signals from one of the photoelectric readers.