Measuring unit

Abstract

The measuring unit (10) comprises a first carriage (12) arranged to be connected to the bending machine and to be passed through by the workpiece (M) under bending coming from the bending machine. The first carriage (12) comprises: a main body (20); a pair of measure rollers (34, 36) mounted on respective support bodies (30, 32) so as to be rotatable about respective axes of rotation (zl, z2) perpendicular to the bending plane; first measuring means (50, 52) arranged to provide a signal indicative of the angular position of each of the measure rollers (34, 36) about the respective axis of rotation (zl, z2); guide means (28) mounted on the main body (20) to guide the support bodies (30, 32) of the measure rollers (34, 36) along a straight direction (y) perpendicular to, and passing through, the axes of rotation (zl, z2) of the measure rollers (34, 36); elastic means (58) arranged to apply on the support bodies (30, 32) an elastic force tending to urge these bodies towards each other, and therefore to urge each measure roller (34, 36) against the workpiece (M) under bending so as to cause each measure roller (34, 36) to roll on a respective intrados surface (S i ) or extrados surface (S e ) of the workpiece (M) while the latter is being forwarded; second measuring means (60) arranged to provide a signal indicative of the distance between the axes of rotation (z1, z2) of the measure rollers (34, 36); and positioning means (66, 68, 74, 76) arranged to define the positioning of the main body (20), and hence of the guide means (28), relative to the workpiece (M) under bending, whereby during bending with a constant bending radius (R i ) the tangent (t) to the longitudinal axis (x) of the workpiece (M) in the point of intersection between this axis (x) and the straight direction (y) of the guide means (28) is perpendicular to this direction (y).

Description

technical field [0001] The invention relates to a measuring unit intended to be used in bending machines, in particular for bending conductors for superconducting coils, in order to measure the bending radius and conveyance of workpieces under bending (forwarding, moving forward) (especially transport after bending), as described in the present invention. Such a measuring unit is known from EP 0 767 016 A2. Background technique [0002] It is known that a workpiece under bending in a bending machine undergoes a change in length due to the plastic deformation experienced by the workpiece during the bending process (the change usually refers to an increase in the length of the workpiece, but it can also refer to the length of the workpiece reduction). As a result, in all those applications where the conveyance of the workpiece needs to be measured in real time, as precisely as possible, in order to be able to control the bending process taking into account the actual measure...

AI Technical Summary

Problems solved by technology

[0005] The main disadvantage of this known solution is that the normal force exerted by the measuring rollers in contact with the outer arc surface of the workpiece causes the workpiece to buckle (at least elastically), which leads to a The change in the curvature of the workpiece at (the lower the bending modulus of the workpiece, the greater the curvature change)

This leads to a reduction in measurement accuracy

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