ES311766A1 - Improvements in or relating to machine tools - Google Patents

Abstract

A nachining device comprises a first rotatable part 1, Fig. 2, for attachment to a machine tool 2 for driving the device in rotation, a second part 3 arranged for rotation with the first part and having means for carrying a tool, such as a grinding wheel, and a dovetail slide which enables the tool to effect a planetary movement of adjustable amplitude with respect to the first part. The second part 3 is also capable of reciprocating movement in the device and is supported in a bore 28a in a body 28. The upper end of part 3 is connected by a pivot 20 to a link 9b having its other end on a pivot 19 extending from a link 9a secured by a bolt 18 and T-part 16 to a shaft 15 rotatable in a hollow body 13, the effective length of the link 9a being adjustable to control the stroke of part 3 when the shaft 15 is rotated. Rotation of the shaft is effected during rotation of the hollow body 13 by successive teeth 8 on a gear 7 formed on the shaft engaging a helical groove 10 in an annular member 11 which can be held against rotation by a pin 5b in a part 5 held stationary during rotation of the hollow body 13 which is secured by a bolt 21, Fig. 1 (not shown) to a circular body 22 secured by a member 23a, 23b and an eccentric pin 24 to the part 1. The rotation of the hollow body 13 is imparted by the dovetail slide to the body 28 carrying the part 3 and the axis YY of the part 3 is adjusted radially of the axis XX of the part 1 by movement of the body 28 along the slide, the movement being effected by rotation of a ring 37 which is mounted on a ball bearing 38 on the stationary part 5 and has an internal thread engaging a thread on a ring-shaped element 31 having a conical inner surface 30 abutting the end of a pin 29 mounted in the body and pressed against the surface by a spring 33. Rotation of the ring 37 vertically displaces the element 31 to move the body 28 along the slide. The lower end of the part 3 is also formed with a dovetail 3a adjustably engaging a slide 4c in a turbine 4 or similar device which carries the grinding tool 4a and is connected by a flexible pipe 4b to a source of compressed air. Tapered surfaces may be ground by adjusting the angle of inclination between the axis YY of part 3 and the axis XX of part 1 by means of a collar 39 having one surface normal to the axis XX and the other inclined thereto, the collar being adjustable relative to both parts by an amount determined by graduations on the part 1 co-operating with an index mark 40 on the collar, a mark 41 on the circular body 22 associated with the part 3 being retained in alignment with the zero of the graduations. In use, the part 5 is held stationary by a ball detent which releases the part if a predetermined tangential force on the part is exceeded.