Abstract: A method of correcting a track of a cutting edge is provided. With movement of the cutting edge, a point on the cutting edge in contact with the rotation symmetry plane is moved along the cutting edge from a first end portion of the cutting edge to a second end portion of the cutting edge opposite to the first end portion. The correction method includes measuring, by a measurement unit, a shape of the cut and machined rotation symmetry plane, calculating, by an operation unit, an error of the measured shape of the rotation symmetry plane from a target shape of the rotation symmetry plane in a direction of the axial line of rotation, and correcting, by the operation unit, a component in the direction of the axial line of rotation of a track of a point of cutting based on the error.

Abstract: Disclosed is a method and apparatus for machining a workpiece (2). The method comprises specifying a path along which a cutting tool (6) is moved during machining the workpiece (2), the path comprising segments (26); defining, for each segment (26), an exit point on that segment (26); defining, for each segment (26), an exit path (38) from the exit point of that segment (26) to a point remote from the workpiece (2); performing a machining process including moving the cutting tool (6) along the tool path and machining the workpiece (2); and, during the machining process, when one or more criteria are satisfied: interrupting the machining process and, without machining the workpiece (2), moving the cutting tool (6) to the exit point of the current segment (26) and then along the exit path (38) of the current segment (26).

Abstract: The present invention discloses a real-time kernel of open CNC systems and a real-time control method of tool-paths. The real-time kernel translates a real-time control of the tool-paths into sending synchronous pulses into the servo drivers in accordance with the control rhythms ?ti (i=1, . . . , n) in the follow-table and achieves the openness of real-time control method and real-time control process. The real-time kernel has the most simple and reliable multi-axis synchronization capability with high-speed and high-precision, and leads to major changes in the field of digital control method. The real-time kernel no need to configure a real-time operating system and a fieldbus, its core function is only to write the control rhythm into the T-division timer, and to send linkage commands into the servo drivers designated by the state-word, therefore its function and architecture are extremely simple and high reliability.

Abstract: A numerical control apparatus includes an imaginary-Y-axis control unit configured to execute an imaginary Y-axis control mode which is a mode for converting an X-Y axes movement command in a machining program described in a program coordinate system into a command in a machine coordinate system including X-H-C axes and for driving the X axis, the H axis, and the C axis in association with one another according to the converted command, an acquiring unit configured to acquire, when an emergency stop occurs during the imaginary Y-axis control mode, present positions of the X axis, the C axis, and the H axis at the time when the emergency stop is released, and a restoring unit configured to restore a present X-axis coordinate position and a present Y-axis coordinate position in the program coordinate system from the acquired present positions of the X axis, the C axis, and the H axis.

Abstract: Machining techniques and machining apparatus are provided for treating workpieces in an efficient and reliable manner. The machining techniques and machining apparatus employ multiple thread whirling heads associated with a single machining assembly, such that each of the thread whirling heads is able to act on a workpiece during a single, uninterrupted machining process. Screw threads may be formed that include first and second thread profiles and an intermediate transition region. The machining apparatus generally includes a processor that is programmed to control operation of the multiple thread whirling heads in a sequential manner.

Abstract: An optical film having structures that vary in height along their length where the variations have a nominal period of less than forty times the nominal height of the structures is taught. In some embodiments of the invention the variation is random.

Abstract: In the thread cutting method according to the present invention, the cutting amount S in each of the thread cutting operations from the second thread cutting operation to the (N-1)th thread cutting operation can be made less than and closest to the allowable cutting amount S.sub.p in each of the thread cutting operations by respectively determining as the cutting amount S.sub.1 in the first thread cutting operation and the cutting amount S.sub.n at a cutting depth which corresponds to the bottom of thread the values which are less than and closest to the allowable cutting amount S.sub.p obtained at the two cutting depths. In consequence, wear of the tool can be reduced and the time required for the thread cutting process can be shortened while the thread cutting accuracy can be maintained high by determining either of two equations from the prerequisites and the processing conditions and then by designating the equation to be adopted.

Abstract: A method for operating a computer controlled industrial machine, such as a lathe, in which a machining operation can be interrupted, a tool displaced from a workpiece and the operation subsequently resumed at the point of interruption. The method includes provision for interrupting canned cycles, such as threadcutting cycles on a lathe, in a manner to prevent damage to any previously cut threads. In one embodiment, the method provides for retrace of prior machining operations before resuming the interrupted operation.

Abstract: A method for the preparation of a spherical hob for generation of a gear, which has a plurality of hob blades formed on the surface of a spherical hob blank, is disclosed. This method comprises forming spirally on the peripheral surface of the hob blank projections having a section defining an involute tooth profile by means of a cutting tool, cutting and forming a plurality of blade spaces intersecting said projections to thereby form a plurality of spirally continuous hob blades, and forming reliefs on the side faces and peripheral face of each hob blade so that as the blade faces of the hob are cut, the tooth profile of each hob blade corresponds to the tooth profile before cutting with a certain amount of addendum.

Abstract: Apparatus for duplicating a master object includes a router which is positioned on a pivoting carriage which has a follower which engages a rotating three dimensional master object. The work piece is rotated at the same rate as the master object and a router carried on the carriage engages the work piece. The location of the axis about which the master object rotates may be varied to change the scale factor so that the work piece may be smaller than the master object.

Abstract: A method and apparatus are disclosed for using a numerically controlled turning machine to automatically cut a thread in response to programmed data defining certain thread cutting parameters. The programmed data defines an initial thread cutting pass and the final thread depth. The method and apparatus cause the cutting tool to make a number of iterative thread cutting passes relative to the rotating workpiece with successive passes being made at correspondingly smaller cutting depths. The threading cycle is terminated by two finish passes at a predetermined minimum depth of cut.