Machine spindle with ejecting means
View Patent ↗A workholding apparatus ( 10 ) wherein a draw bar ( 22 ) effects chucking and de-chucking of a workpiece (W) and wherein un-seating of the workholding apparatus is effected by piston-like mechanisms ( 30 ) located in a machine spindle ( 2 ).
1. A machine spindle rotatable about an axis of rotation, said spindle comprising a spindle body having an outer end with said outer end having an opening and an end surface surrounding said opening, thereby providing, within said spindle body, for a seated position for a workholding apparatus in the form of a chuck or an arbor, said spindle further comprising:
a plurality of rod-shaped ejecting elements located in said outer end at said end surface with each of said rod-shaped ejecting elements being extendable from said end surface and retractable into said end surface,
said rod-shaped ejecting elements being operable to extend from said end surface and into contact with a surface of a workholding apparatus located in said seated position, said contact being of a force sufficient to urge said workholding apparatus from said seated position.
2. The machine spindle of claim 1 wherein said rod-shaped ejecting element comprises a piston.
3. The machine spindle of claim 2 wherein said piston is located within a piston retainer.
4. The machine spindle of claim 1 wherein said rod-shaped ejecting elements are extendable via fluid pressure.
5. The machine spindle of claim 4 further comprising said rod-shaped ejecting elements being extendable via springs.
6. The machine spindle of claim 1 further comprising said rod-shaped ejecting elements being retractable via springs.
7. The machine spindle of claim 1 wherein said plurality of rod-shaped ejecting elements are spaced equidistantly about said end surface.
8. The machine spindle of claim 1 wherein said plurality of rod-shaped ejecting elements are spaced radially equidistantly from said axis of rotation.
9. A method of breaking the seating contact between a machine spindle and a workholding apparatus in the form of a chuck or an arbor seated within said spindle, said method comprising:
providing a machine spindle rotatable about an axis of rotation, said spindle comprising a spindle body having an outer end with said outer end having an opening and an end surface surrounding said opening, said spindle further comprising a plurality of rod-shaped ejecting elements located in said outer end at said end surface with each of said rod-shaped ejecting elements being extendable from said end surface and retractable into said end surface,
extending said rod-shaped ejecting elements from said end surface,
bringing said rod-shaped ejecting elements into contact with a surface of the seated workholding apparatus, said contacting being of a force sufficient to urge said workholding apparatus from the seated contact.
10. The method of claim 9 wherein said rod-shaped ejecting elements comprise pistons.
11. The method of claim 9 wherein said extending of said rod-shaped ejecting elements is effected by fluid pressure.
12. The method of claim 9 further comprising retracting said rod-shaped ejecting elements.
13. The method of claim 9 wherein said retracting is effected by springs.