Machine for grinding and polishing workpieces

Machine for grinding and polishing workpieces having a spherical surface, such as spectacle glasses, lenses, and the like, which comprises

• a workpiece support disposed for rotation about an axis for mounting the workpiece for exposure during the machining operation to the action of a work tool operatively applied against the workpiece,
• a work tool holder for operatively holding the work tool for carrying out such action,
• a rocker connected to the work tool holder to form a unit therewith and mounted for reciprocating movement about an axis of pivot arranged normal to the axis of rotation of the workpiece support,
• the rotation axis of the workpiece support lying in a first plane and the pivot axis of the rocker lying in a second plane parallel to and disposed at a fixed distance from the first plane,
• a reciprocating drive for effecting reciprocating movement of the rocker and work tool holder and including a reciprocating means having a constant operative amplitude of reciprocating movement, and
• an intermediate selectively variable drive transmission means operatively interconnecting the constant amplitude reciprocating means of the reciprocating drive with the rocker and having a variable operative drive transmission ratio for selective adjustment of the amplitude of reciprocating movement of the rocker and work tool holder.

Machine for grinding and polishing workpieces having a spherical surface, such as spectacle glasses, lenses, and the like, which comprises

• a work tool,
• a workpiece support disposed for rotation about an axis for mounting the workpiece for exposure during the machining operation to the action of the work tool operatively applied against the workpiece, said workpiece support having a spherical workpiece receiving surface provided with a predetermined radius of curvature corresponding to that of the spherical surface of the workpiece to be operatively mounted thereon and situated such that the center of such radius of curvature coincides with the rotation axis of the workpiece support,
• a work tool holder including a pressure spindle sleeve for operatively holding the work tool for carrying out such action and for maintaining the work tool against the workpiece under operatively applied pressure,
• a rocker connected to the work tool holder to form a unit with the pressure spindle sleeve and mounted for reciprocating movement about an axis of pivot arranged normal to the rotation axis,
• the rotation axis of the workpiece support lying in a first plane and the pivot axis of the rocker lying in a second plane parallel to and disposed at a fixed distance from the first plane,
• a reciprocating drive including a crank drive for effecting reciprocating movement of the rocker and pressure spindle sleeve and further including a reciprocating crank arms means having an invariably constant operative crank radius and corresponding amplitude of crank reciprocating movement, and
• an intermediate selectively variable drive transmission means operatively interconnecting the crank arm means and the rocker and having a variable operative drive transmission ratio for selective adjustment of the amplitude of the reciprocating movement of the rocker and pressure spindle sleeve, said intermediate drive transmission means being arranged for variation during reciprocating movement of the rocker by the crank drive and including an adjustable drive transmission linkage having an operative adjustment range selectively varying from a maximum amplitude of reciprocating movement determined by the corresponding constant operative amplitude of the crank radius to an approximately zero amplitude of reciprocating movement.