Patent ID: 6848190

Claim:
An apparatus for checking a crankpin, orbitally rotating about a geometrical axis, in the course of the machining in a numerical control grinding machine including a worktable, defining said geometrical axis, and a grinding-wheel slide carrying a grinding-wheel, with a Vee-shaped reference device for cooperating with the crankpin to be checked, a measuring device movable with the Vee-shaped reference device, a support device for supporting the Vee-shaped reference device and the measuring device, the support device having a support element fixed to the grinding-wheel slide, a first coupling element coupled to the support element so as to rotate about an axis of rotation parallel to said geometrical axis, a second coupling element carrying the Vee-shaped reference device and coupled to the first coupling element so as to rotate with respect to it about a second axis of rotation parallel to said geometrical axis, a control device for controlling automatic displacements of the apparatus from a rest position to a checking condition, and vice versa, and a guiding mechanism, associated with the Vee-shaped reference device for guiding the arrangement of the latter on the crankpin towards said checking condition of the apparatus, and including a limiting device with an elongate rigid element, a substantially tubular element, coupled to the first coupling element, that bears and guides the elongate rigid element along a direction substantially parallel to the first coupling element and abutment elements connected to the grinding-wheel slide and the second coupling element, the elongate rigid element is adapted to engage with the abutment elements and limit movements of the Vee-shaped reference device during said automatic displacements towards the checking condition.