Machine and method for marking hollow parts

Abstract

This machine for marking hollow parts comprises a marking member designed to be on contact in at least one line of tangency with a hollow part for it to be marked, and a first and a second mandrel capable of supporting respectively a first part to be marked and a second part previously marked. A control camera is placed at a focal length from the marked surface of the second part. The first mandrel is capable of moving the first part relative to the marking member and the movement of the second mandrel is slaved and identical to that of the first mandrel. The camera is capable of moving parallel to, and in synchronism with, the line of tangency between the marking member and the first part.

Description

The features and advantages of the invention will appear in the following description of an embodiment of a machine for marking hollow parts according to the invention, given only as an example and made with reference to the appended drawings in which:

FIG. 1 is a view in perspective of a machine for marking hollow parts according to the invention, prior to the marking and quality control;

FIG. 2 is a view in perspective of a transfer manipulator belonging to the machine of FIG. 1;

FIGS. 3 to 7 are schematic partial front views of certain elements of the machine of FIG. 1 showing successive steps of a method for marking hollow parts and for controlling the quality of their marking according to the invention.

Claims

1. A machine for marking hollow parts, comprising a marking member designed to be in contact on at least one line of tangency with a hollow part for it to be marked, and first and second mandrels capable of supporting respectively a first part to be marked and a second part previously marked on the first mandrel by the marking member, a control camera being placed at a focal length from the marked surface of the second part, wherein the first mandrel is capable of moving the first part relative to the marking member in rotation about an axis and in translation parallel to two axes perpendicular to one another and to the axis of rotation, the movement of the second mandrel being slaved and identical to that of the first mandrel and the camera being capable of moving parallel to, and in synchronism with, the line of tangency between the marking member and the first part.

2. The marking machine as claimed in claim 1, wherein the tangential speed of the first part relative to the marking member is substantially constant.

3. The marking machine as claimed in claim 1, wherein the frequency of the camera shots depends on the tangential speed of the first part relative to the marking member.

4. The marking machine as claimed in claim 1, wherein the first and second mandrels are mounted on one and the same support that moves them parallel to said axes of translation.

5. The marking machine as claimed in claim 1, wherein it comprises means for rotationally synchronizing the first and second mandrels.

6. The marking machine as claimed in claim 4, wherein it comprises a manipulator for transferring parts between the first and second mandrels, said support being movable between a second position in which the manipulator is capable of unloading a part from the first mandrel and a first position in which the manipulator is capable of loading said part onto the second mandrel.

7. The marking machine as claimed claim 1, wherein the marking member is a flat stamp or a screen-printing doctor blade.

8. A method for marking a hollow part and for controlling the quality of its marking, wherein it comprises steps in which: a marking member marks the part, the part being moved relative to the marking member, by a first mandrel, in rotation about an axis and in translation parallel to two axes perpendicular to one another and to the axis of rotation;a camera controls the quality of the marking of the part by moving at a focal length from the marked surface of the part, the part being moved by a second mandrel whose movement is identical to that of the first mandrel.

9. The method for marking a hollow part and for controlling the quality of its marking as claimed in claim 8, wherein it comprises steps in which: when the part is marked by the marking member, a support, to which the first and second mandrels are connected, moves parallel to said axes of translation from a first position to a second position;the part is unloaded from the first mandrel by a manipulator for transferring the part between the first and second mandrels, this manipulator being capable of unloading the part from the first mandrel in said second position of the support and of loading the part onto the second mandrel in said first position of the support;the support moves from said second position to said first position;the manipulator loads the part onto the second mandrel;the camera controls the quality of the marking of the part supported by the second mandrel.

10. The method for marking a hollow part and for controlling the quality of its marking as claimed in claim 8, wherein each picture taken by the camera is corrected to take account of relative vibrations of the second mandrel and the camera.