An ultrasonic non-destructive test Device (1) of hybrid electromagnetic acoustic/Laser transducers type comprising a monolithic Rotating Optical Assembly (22) of agile laser array transmitters providing multifocal laser beams guidance by jumps for the control of metallurgical objects, to equip a Machine Tool (2) carrying out quality control of metal processing, on a Control Area (3) of the Surface (4) of a Metal Workpiece (5), of the type inducing Mechanical Vibrations (8) in the Body (9) the Metal Workpiece (5), and, monitoring generated ultrasonic Induced Signals (11) to identify Surface Discontinuities (12) and Sub-Surface Discontinuities (13);
- this Device (1) comprising:
- (a) a Rotating Shaft (14), capable of rotating about a Rotation Axis (15);
- (b) an Incoming Laser Source (16), equipped with Optical Guidance Means (17), configured to produce an Incoming Laser Beam (18), with a certain Incoming Laser Power (PI), directed along an Incoming Beam Axis (20) parallel to the Rotation Axis (15), this at a certain Beam Distance (21) from the Rotation Axis (15);
- (c) a Rotating Optical Assembly (22) configured to rotate about the Rotation Axis (15);
- and incorporating a Reflector Assembly (25), (i) composed of a plurality of n (at least two) Mirrors (M, M1, M2 . . . , M11, M21 . . . , M24), acting as an Optical Barrier (27), (ii) each of which Mirrors (M, M11) being configured so that, in certain rotary positions of the Rotating Optical Assembly (22), the Mirror (M) intercepts the Incoming Beam Axis (20), (iii) each of which Mirror (M) having a Reflection Point (29, 29-11), i) being positioned at a rotating Reflection Distance (32) perpendicular to the Rotation Axis (15), ii) for reflecting the Incoming Laser Beam (18) impacted on this Mirror (M), iii) with a change in Beam Angular Direction (A), and, iv) with a Reflection Efficiency (E) of the energy of the Incoming Laser Beam (18) substantially equal to one hundred percent;
- (iv) geometrically configured such that, i) the Incoming Laser Beam (18) successively impacts a Reflection Point (29, 29-11) associated with and belonging to one of its n distant Mirrors (M, M11), ii) each of n Reflection Points (29, 29-11) of the n Mirrors (M), travels through a Circle of Rotation (C, C-1 . . . , C-11 . . . ), of a Radius of Rotation (37, 37-1 . . . 37-11 . . . ), centered on a Center of Rotation (CR, CR-1 . . . , CR-11 . . . ) fixed on the Rotation Axis (15), and iii) the n different Mirrors (M, M1, M2 . . . , M11, M21 . . . . M24) redirect in an agile manner, successively and discontinuously the Incoming Laser Beam (18) according to a Secondary Beam Collection (44), made of a bundle of n distant Secondary Laser Beams (45, 45-1 . . . , 45-11 . . . , 45-24), resulting from a multitude of successive and discontinuous changes in the Beam Angular Direction (A) of the Incoming Laser Beam (18), by reflection on the succession of n Mirrors (M) distant and in rotation;
- and, (v) geometrically configured such that the n Secondary Laser Beams (45) generated successively impact an Impact Set (46) made up of a multitude of n distant Impact Points (47, 47-1, 47-11 . . . , 47-21 . . . , 47-24), located i) either on the Impact Plane (48), facing the Rotating Optical Assembly (22), located on the Surface (4) of the Control Area (3), and near a Detection Point (36) of an EMAT type Electromagnetic Acoustic Transducer (34), or, ii) either on an Auxiliary Mirror (49, 49-21 . . . , 49-24);
- (d) Rotation Means (24) of the Rotating Optical Assembly (22), (i) comprising a Drive Motor (24-a), connected to the Rotating Shaft (14), and, (ii) configured to induce a rotation of the Rotating Shaft (14) around the Rotation Axis (15), with a continuous Direction of Rotation (DR);
- (e) a Sensor Assembly (33), composed of a plurality of p (at least two) EMAT type Electromagnetic Acoustic Transducer (34), hereinafter referred to as EMATs, each of which Active Electromagnetic Probe (35);
- (i) faces the Control Area (3) and is substantially centered on a Detection Point (36) of the Control Area (3), and, (ii) is configured to generate an A-Scan Signal (AS) for detecting the position of the Defaults (12, 13) versus time/distance, acquired from the Induced Signals (11) in the vicinity of its Detection Point (36):
- this Device (1) being characterized in that it presents the following combination of technical features:
- a. its Rotating Optical Assembly (22), including its n Mirrors (M), their mechanical connection parts and its n associated Reflection Points (29, 29-11), in rotation, (i) is monolithic, that is to say it is made up of mechanical and/or optical parts all rigidly mechanically linked together and in fixed, non-modifiable position relative to each other, and, (ii) is rigidly fixed by Fixing Means (23) on the same Rotating Shaft (14), and, (iii) has a rigid geometry that is non-deformable during its rotation:
- b. the n Mirrors (M) of the Reflector Assembly (25) and their n associated Reflection Points (29, 29-11) are in fixed position relative to the same Rotation Axis (15);
- c. the rotating Reflection Distances (32) of the n Reflection Points (29, 29-11) of all the Mirrors (M), perpendicularly and with respect to the Rotation Axis (15), are all (i) constant and equal to each other during said rotation, and (ii) substantially equal to the Beam Distance (21);
- d. each of the n Reflection Points (29, 29-11) of the n Mirrors (M), travels through a Circle of Rotation (C, C-1, . . . , C-11, . . . ), (i) centered on the Rotation Axis (15), and (ii) maintained perpendicular to the Rotation Axis (15) during said rotation;
- e. each of the n Circles of Rotation (C) (i) presents a projection, parallel to a projection plane parallel to the Rotation Axis (15) and passing through its Center Of Rotation (CR, CR-1, . . . , CR-11, . . . ), formed of a Segment of Transverse Cross-Motion (ST, ST-1, . . . , ST-11, . . . ), perpendicular to the Rotation Axis (15) and centered on its Center of Rotation (CR), and, (ii) presents a projection, parallel to a plane of rotation perpendicular to the Rotation Axis (15) and passing through its Center of Rotation (CR, CR-1, . . . , CR-11, . . . ), formed of a Circle Of Planar Projected Motion (CP, CP-1, . . . , CP-11, . . . ), coincident with the Circle of Rotation (C), and having a Radius Of Projected Rotation (RP, RP-1, . . . , RP-11, . . . ), equal to the Beam Distance (21) during said rotation;
- f. each Reflection Point (29) of a Mirror (M) is positioned in a fixed manner with respect to the same rotating Cylindrical Reflection Surface (38) of a Virtual Reflection Cylinder (39) of revolution and rotating, (i) having a constant circular section, (ii) in rotation around the Rotation Axis (15), (iii) whose Reflection Cylinder Radius (41) is constant and substantially equal i) to the Radii of Rotation (37, 37-1, . . . , 37-11, . . . ) of each of the n Circles of Rotation (C, C-1, . . . , C-11, . . . ), and, ii) to the Beam Distance (21), (iv) so that the cross section of the Virtual Cylinder Reflection (39) of revolution and its rotating Cylindrical Reflection Surface (38) is constantly circular, (v) but whose longitudinal position is fixed with respect to the Rotating Shaft (14), that is to say without any longitudinal movement with respect to the Rotation Axis (15);
- g. the Reflection Points (29) of the Mirrors (M) are positioned on a rotating Helical Dotted Line (43), (i) with circular helical winding, of radius equal to the Beam Distance (21), (ii) and with circular cylindrical screw thread, (iii) fixed together with its points on the Cylindrical Reflection Surface (38), and in rotation with it, but, (iv) whose longitudinal position is fixed with respect to the Rotating Shaft (14), that is to say without any longitudinal displacement with respect to the Rotation Axis (15);
- h. the Incoming Laser Beam (18) is, during its rotation, positioned along successive rectilinear Reflection Generating Lines (42) of the rotating Cylindrical Reflection Surface (38), (i) each attached to a Reflection Point (29) of a Mirror (M), (ii) moving in rotation with the Virtual Reflection Cylinder (39), (iii) but without longitudinal movement with respect to the Rotation Axis (15).