A cutting apparatus adapted for use in a machine tool. The cutting apparatus includes a mounting frame. A cutting unit is mounted rotatably in the mounting frame. A locking unit is connected to the mounting frame and the cutting unit, for restraining or permitting relative movement between the mounting frame and the cutting unit. A driving unit drives rotation of the cutting unit. A control unit controls the driving unit to drive rotation of the rotating shaft upon detecting that the relative movement between the mounting frame and the cutting unit is permitted. The control unit shuts off the driving unit upon detecting that the relative movement between the mounting frame and the cutting unit is restrained.

A cutting apparatus adapted for use in a machine tool. The cutting apparatus includes a mounting frame. A cutting unit is mounted rotatably in the mounting frame. A locking unit is connected to the mounting frame and the cutting unit, for restraining or permitting relative movement between the mounting frame and the cutting unit. A driving unit drives rotation of the cutting unit. A control unit controls the driving unit to drive rotation of the rotating shaft upon detecting that the relative movement between the mounting frame and the cutting unit is permitted. The control unit shuts off the driving unit upon detecting that the relative movement between the mounting frame and the cutting unit is restrained.

A cutting method in which, in cutting a circumferential face of a work, control is enabled to make a cutting velocity constant accurately by using a cutting tool projecting from a main shaft which turns around a predetermined position serving as a center and for which a turning radius is adjustable, wherein, in the case that a turning angular velocity of the main shaft is represented as , a distance from a turning center to a tip of the cutting tool is represented as R, and a cutting velocity of the tip of the cutting tool is set to a constant value C, making the cutting velocity of the cutting tool constant by performing control such that 0 changes in association with a change in the distance R so that

=(C.sup.2{dot over (R)}.sup.2).sup.1/2/R

is formulated (where {dot over (R)} denotes a time differential of the distance R), thus providing an even cut face.

A lens mount for radially fixing, or for radially adjusting and fixing, in a lens tube, having a mounting ring in which tangentially running first slots form cylindrical segments which, during the operation of turning the external diameter of the mounting ring to a nominal dimension are deformed by a screw by a width of the first slots, and therefore the circumferential surface of the mounting ring is not turned, at least in part, along the segment and the external diameter has an oversize.

A lens mount for radially fixing, or for radially adjusting and fixing, in a lens tube, having a mounting ring in which tangentially running first slots form cylindrical segments which, during the operation of turning the external diameter of the mounting ring to a nominal dimension are deformed by a screw by a width of the first slots, and therefore the circumferential surface of the mounting ring is not turned, at least in part, along the segment and the external diameter has an oversize.

A polygon machining method whereby first polygon machining is carried out on a workpiece held by a main axis, by using a polygon cutter attached to a tool main axis, then machining using a tool other than the polygon cutter is carried out, and second polygon machining after said machining is carried out, using the polygon cutter. The polygon machining method comprises: a synchronized stopping step in which the main axis is stopped at a predetermined prescribed rotation position, in a state in which the main and the tool main axis during polygon machining are synchronously rotated when the first polygon machining has been completed; a synchronization release step in which the synchronization of the main axis and the tool main axis is released when starting machining after the first polygon machining; a main axis stopping step in which the main axis is stopped at a prescribed rotation position when the machining after first polygon machining has been completed; and a synchronization starting step in which the main axis and the tool main axis are synchronously rotated when starting second polygon machining.

A polygon machining method whereby first polygon machining is carried out on a workpiece held by a main axis, by using a polygon cutter attached to a tool main axis, then machining using a tool other than the polygon cutter is carried out, and second polygon machining after said machining is carried out, using the polygon cutter. The polygon machining method comprises: a synchronized stopping step in which the main axis is stopped at a predetermined prescribed rotation position, in a state in which the main and the tool main axis during polygon machining are synchronously rotated when the first polygon machining has been completed; a synchronization release step in which the synchronization of the main axis and the tool main axis is released when starting machining after the first polygon machining; a main axis stopping step in which the main axis is stopped at a prescribed rotation position when the machining after first polygon machining has been completed; and a synchronization starting step in which the main axis and the tool main axis are synchronously rotated when starting second polygon machining.

A cutting method for an inner circumferential face or an outer circumferential face of a work using a cutting tool projecting from a main shaft which turns around a predetermined position serving as a center and for which a turning radius is adjustable, wherein a table that supports the work is set in a rotating central axis that is coaxial with a turning central axis of the main shaft, and the table is rotated in a direction opposite to a turning direction of the main shaft to summate a cutting velocity. The cutting method allows a summation to the cutting velocity under simple control.

A cutting method in which, in cutting an inner circumferential face or an outer circumferential face of a work based on turning of a main shaft around a predetermined position serving as a center, control is enabled to make a cutting velocity constant. To achieve the object, a cutting method is provided for an inner circumferential face or an outer circumferential face of a work, using a cutting tool projecting from a main shaft which turns around a predetermined position serving as a center and for which a turning radius is adjustable, wherein, in the case that a turning angular velocity of the main shaft is represented as , a distance from a turning center to a tip of the cutting tool is represented as R, and a cutting velocity of the tip of the cutting tool is set to a constant value C, making the cutting velocity of the cutting tool is made constant by performing control such that changes in association with a change in the distance R so that

[00001]$={\left(C^2-{\stackrel{.}{R}}^2\right)}^{\frac{1}{2}}/R$

is formulated (where {dot over (R)} denotes a time differential of the distance R), thus providing an even cut face.

A lathe control system used for three dimensional curved surface machining includes an input module, a control module, a work table, a feeding module, a first sliding module, a second sliding module, and a cutter. The control module is electrically connected with the input module, the feeding module, the first sliding module, and the second sliding module. The first sliding module drives the feeding module to move along a first direction. The second sliding module drives the feeding module to move along a second direction perpendicular to the first direction. The cutter is positioned on the feeding module. The feeding module is capable of driving the cutter to move back and forth along a third direction under the control of the control module. The third direction is perpendicular to first and second direction.