Apparatus and method for checking tyres

A method for checking tyres, comprising:

• arranging a tyre to be checked;
• arranging an apparatus for checking tyres, wherein the apparatus for checking tyres comprises:
• a support frame;
• a flange fixed on the support frame for attaching the support frame to a movement member of the apparatus;
• and
• an acquisition system for acquiring three-dimensional images of a surface of a tyre, wherein the acquisition system is mounted on the support frame and comprises:
• a matrix camera with an optical axis,
• a linear laser source to emit a linear laser beam having a propagation plane and a propagation axis, and
• a reflecting element with a reflecting surface which intersects both the propagation axis and the optical axis to respectively identify a first section and a second section of the propagation axis and a first section and a second section of the optical axis, wherein:
• the first section and the second section of the propagation axis are rectilinear sections incident on the reflecting surface in a respective point of incidence and mirror each other with respect to a line perpendicular to the reflecting surface in the respective point of incidence;
• the first section and the second section of the optical axis are rectilinear sections incident on the reflecting surface in a respective point of incidence and mirror each other with respect to a line perpendicular to the reflecting surface in the respective point of incidence;
• the first section of the propagation axis is situated on the side of the matrix camera with respect to the point of incidence and the first section of the optical axis is situated on the side of the linear laser source with respect to the respective point of incidence;
• a first angle formed between the first section and the second section of the optical axis is obtuse;
• and
• a second angle formed between the first section and the second section of the propagation axis is obtuse,
• inserting at least the reflecting element in a space inside the tyre;
• illuminating a linear portion of an internal surface of the tyre with the linear laser beam to generate a laser line;
• acquiring a matrix image of an internal surface portion containing the linear portion of the internal surface, wherein the matrix image comprises a reflected laser line representing the laser line;
• identifying the reflected laser line in the matrix image;
• and
• processing the reflected laser line via triangulation to obtain a three-dimensional image of the linear surface portion representing an altimetric profile of the linear surface portion.