Retractable friction stir welding spindle
The invention provides a retractable friction stir welding spindle, aims at the deficiencies and defects of the existing friction stir welding spindle technology, that is, when the welding is finished, the stirring needle leaves a keyhole at the end of the weld seam, which affects the forming performance of the workpiece, the overall structure design of the spindle is complicated with many transmission chains and low reliability which is difficult to realize modularization. The retractable friction stir welding spindle includes an electric spindle system and a retracting mechanism. The electric spindle system includes stirring shaft shoulder, hilt, front end cover, hollow spindle, motorized spindle shell, motor rotor, motor stator, tail end cover, etc. The retracting mechanism includes stirring needle, connecting ball head and electric cylinder. The invention has the advantages of simple structure and can be mainly divided into two modules to improve reliability and integrity. The invention can also avoid the generation of friction stir welding keyhole.
1. A retractable friction stir welding spindle comprising:
an electric spindle system and a retracting mechanism;
wherein, in the electric spindle system, a first angular contact ball bearing ( 7 ) is installed inside a front bearing chamber ( 5 ), a rear end of the first angular contact ball bearing ( 7 ) is locked by a first threaded retaining ring ( 8 ), a left side face of a connecting sleeve ( 16 ) is fixed with an outer edge of an electric spindle shell ( 9 ) by bolts, and an end cover ( 18 ) is fixed with an end face of the connecting sleeve ( 16 ) by bolts; a hilt ( 2 ) is assembled on an end face of a hollow spindle ( 4 ) by bolts, and a stirring shaft shoulder ( 1 ) is installed and fixed with an inner hole of the hilt ( 2 ), forming an electric spindle without retracting function; a motor rotor ( 10 ) rotates after energization and drives the hollow spindle ( 4 ) to rotate, so that the hilt ( 2 ) and the stirring shaft shoulder ( 1 ) rotate together;
in a retracting machine, a stirring needle ( 19 ) and a retracting structure ( 20 ) are connected by threads and then stretch out from the stirring shaft shoulder ( 1 ), a rear part of the retracting structure ( 20 ) of the retracting machine is connected to a tail end cover ( 18 ) by bolt;
when the electric spindle is energized, the motor rotor ( 10 ) therein rotates, driving the hollow spindle ( 4 ) to rotate at a high speed to complete spindle moving function; up and down translation motion of the retracting mechanism is completed by the retracting structure ( 20 ), so that the stirring needle ( 19 ) completes the function of gradual retraction, and then realizes function of eliminating keyhole in the friction stir welding;
in the electric spindle system, a motor stator ( 11 ) is installed at one end of the electric spindle shell ( 9 ), and a side surface of the motor stator ( 11 ) is fixed to an inner wall of the electric spindle shell ( 9 ); the motor rotor ( 10 ) is installed on a fourth stepped shaft of the hollow spindle ( 4 ) with an interference fit, and its position is matched with the motor stator ( 11 ), the first angular contact ball bearing ( 7 ) is fitted with the hollow spindle ( 4 ).
2. The retractable friction stir welding spindle according to claim 1 , wherein, in the electric spindle system, the front bearing chamber ( 5 ) and the end face of the other end of the electric spindle shell ( 9 ) are fixed by bolts, the front end cover ( 3 ) is fixed on the left end face of the front bearing chamber ( 5 ) by bolts; the rear bearing chamber ( 12 ) is fixed on the right end face of the electric spindle shell ( 9 ) by bolts, a second angular contact ball bearing ( 13 ) is installed into a hole of rear bearing chamber ( 12 ), and the second angular contact ball bearing ( 13 ) is also assembled on a first step shaft on the right side of the hollow spindle ( 4 ).
3. The retractable friction stir welding spindle according to claim 1 , wherein, in the electric spindle system, a rear bearing chamber end cover ( 14 ) is fixed on the right end face of the rear bearing chamber ( 12 ) by bolts, an encoder ( 15 ) is fixed on the right end face of the rear bearing chamber end cover ( 14 ), the remaining parts of the encoder ( 15 ) are installed on the first stepped shaft on the right side of the hollow spindle ( 4 ), and is locked by a second thread retaining ring ( 17 ).