An oscillation component a×sin(Mωt) (M is the number of sides) that becomes the maximum when a tool cuts the center of a machining surface is superimposed on a reference angular velocity 2ω of the tool. The angular velocity of a tool shaft becomes higher as the tool shaft comes close to the center of the machining surface and becomes the maximum when the tool shaft is at the center of the machining surface. It is possible to adjust the flatness of the machining surface by adjusting an adjustment parameter a of the oscillation component a×sin(Mωt).

Oscillation for a direct distance between the centers of a tool T and a workpiece W to meet l+a×l×(1−cos(Mωt)) and vertical oscillation to meet a×l×sin(Mωt) are applied alone or in combination with time t, where ω denotes an angular velocity of a workpiece, M denotes the number of sides of a polygon, and a denotes an adjustment parameter. Such oscillation enables adjustment as to how the machining surface is made concave or convex.

An apparatus to produce a letterbox using a strip of material includes: a bender to receive and bend the strip of material into a desired shape of a letterbox including flanges and notches, and the bender to bend at least one end of the strip of material slightly to produce a slight bent; a processor to measure a first plurality of hole positions on a first end of the strip of material and a second plurality of hole positions on flanges of the strip of material, wherein the first plurality of hole positions on the first end are measured to match a first plurality of holes on a second end of the strip of material, wherein the second plurality of hole positions on the flanges are measured to match a second plurality of holes on a base plate; and a puncher to punch the first plurality of holes on at least one of the first end and the second end of the strip of material according to the first plurality of hole positions, and the puncher to punch the second plurality of holes on the flanges according to the second plurality of hole positions.

An apparatus to produce a letterbox using a strip of material includes: a bender to receive and bend the strip of material into a desired shape of a letterbox including flanges and notches, and the bender to bend at least one end of the strip of material slightly to produce a slight bent; a processor to measure a first plurality of hole positions on a first end of the strip of material and a second plurality of hole positions on flanges of the strip of material, wherein the first plurality of hole positions on the first end are measured to match a first plurality of holes on a second end of the strip of material, wherein the second plurality of hole positions on the flanges are measured to match a second plurality of holes on a base plate; and a puncher to punch the first plurality of holes on at least one of the first end and the second end of the strip of material according to the first plurality of hole positions, and the puncher to punch the second plurality of holes on the flanges according to the second plurality of hole positions.

A device for the machining of curved laminar surfaces, having a first part including a tool for machining the concave face of the surface, and first pressure device in contact with the concave face of the surface, a second part including second pressure device in contact with the convex face of the surface, and devices synchronizing the movements of the first and second parts is provided. The tool has a circular shape for the radial machining of the concave face, and the first pressure device has at least one disc parallel to the tool, the tool and disc disposed on a rotary shaft and both having a radius equal to or less than the radius of curvature of the concave face.

An automatic lathe includes a main spindle that rotates a workpiece about a shaft center, a cutting tool that processes the workpiece, a feeder that moves the cutting tool, an input receiver that receives inputs regarding an eccentric distance and a radius, and a controller that controls the movement by the feeder such as to set a virtual circle having a radius of the distance, to set an offset virtual circle having a center at a position where a center of the virtual circle is offset from the shaft center of the workpiece in the radial direction of the workpiece by the radius, and to move the cutting tool along an circumference of the offset virtual circle in relation to a rotation of the workpiece by the main spindle. A hole is processed, which has the radius at a position away from the shaft center by the distance.

The disclosure relates to a tool spindle with a spindle housing, a rotary drive, a tool receiving unit, wherein the tool receiving unit is arranged within the spindle housing and is movable with respect to the housing, which tool receiving unit can be used multi-functionally, and with which both conventional machining operations such as drilling and milling as well as turning and novel machining operations, such as cam turning, can be performed without damaging the spindle and with high industrial manufacturing quality.

The disclosure relates to a tool spindle with a spindle housing, a rotary drive, a tool receiving unit, wherein the tool receiving unit is arranged within the spindle housing and is movable with respect to the housing, which tool receiving unit can be used multi-functionally, and with which both conventional machining operations such as drilling and milling as well as turning and novel machining operations, such as cam turning, can be performed without damaging the spindle and with high industrial manufacturing quality.

A method for machining of ball tracks of an inner race of a constant velocity joint includes the step of providing a power skiving tool having a plurality of cutting members and a first axis of rotation and providing a work piece having an outer envelope surface extending along an axis of rotation. The first axis of rotation of the power skiving tool is arranged at a first distance from the axis of rotation of the work piece and oriented at a first angle. A first rotational speed to the power skiving tool and a second rotational speed to the work piece and a relative movement between the work piece and the power skiving tool, is applied such that the cutting members engage the outer envelope surface to machine the ball tracks. A cutting insert and a power skiving cutting tool are also provided.

Tool assembly for a rotating device having a drive, a control and a supporting arrangement for at least one tool insert. In order to provide a device for off-round turning which can be constructed with little technical and mechanical effort and nonetheless be used at almost any axial position of a workpiece, the application proposes a tool assembly of the type mentioned above. The tool assembly is designed as a crank drive assembly, wherein the supporting arrangement has a swinging piston unit and the crank drive assembly has a crank unit, and the swinging piston unit and the crank unit are connected to one another by a thrust rod unit.