Abstract: A manufacturing method for an optical element includes providing a base member for an optical element and a cutting tool from which a blade tip part protrudes, forming an inspecting groove on a surface of the base member by the blade tip part of the cutting tool by relatively moving the cutting tool and the base member while the cutting tool is rotated and inspecting an inclination of a cut surface of the inspection groove formed by the cutting tool to form an inspection result. The method also includes correcting an angle defined by the base member and the blade tip part of the cutting tool based on the inspection result and forming formal grooves on the surface of the base member having the inspection groove by the blade tip part of the cutting tool by relatively moving the cutting tool and the base member while the cutting tool is rotated simultaneously with the inspection groove being cut out.

Abstract: A feedback compensating apparatus for adjusting the working condition of a working machine of a working system adapted to process working portions of successive workpieces under control of a machine controller, which determines the working condition from an extraneous signal. The apparatus is used with the controller and a measuring device for measuring the dimensions of the processed working portions of the workpieces, and includes a device for obtaining dimensional data based on outputs of the measuring device during and/or after a working operation of the machine on each workpiece. The dimensional data include a dimensional error of the processed working portions, and a variable indicative of a tendency of change in the dimensional error. The apparatus further includes a device for determining the extraneous signal based on the dimensional data, and applying the signal to the machine controller to adjust the working condition of the machine.

Abstract: A method for automatically correcting the systematic errors in measurement machines and in manufacturing machines, in particular in machine tools, characterized by comprising the following operative steps in succession: identifying the parametric mathematical model of the machine, initially assigning, to the parameters of said parametric mathematical model, numerical values considered to be close to the effective values, to obtain a provisional mathematical model of the machine, effecting a plurality of mutually independent distance measurements within the working field of the machine, determining the differences between the experimentally measured distance values and the corresponding distance values deduced from said provisional mathematical model, to define the corresponding provisional inaccuracy index of the machine, varying said parameters in the sense of improving the predefined provisional inaccuracy index, to hence obtain a new provisional mathematical model of the machine which is closer to its defi

Abstract: Large machines, especially those having working envelopes in excess of fifteen feet, exhibit unacceptable errors because of thermal expansion and mechanical misalignments between the axes. The errors have traditionally been minimized by enclosing the machine in a thermal enclosure, by careful calibration, or by mounting a laser interferometer on each axis. These solutions are costly, may require frequent recalibration, and do not correct for small rotations of one axis relative to another axis due to wear etc. The present invention uses an interferometric laser tracker or a comparable 3D position sensor to measure the position of a retroreflector attached to the end effector, e.g. a machine head when the machine comes to rest. A computer compares the measured position to the desired position according to the machine media, and adds the appropriate correction with trickle feed media statements to move the machine to the correct position prior to further machining.

Abstract: An operation command for constructing compensation data is generated in a control device, and measurement data obtained from an external length measuring device is input to an input unit. The measurement data is compared with an estimated position in a control device of a cylinder servo motor, and errors between them is stored in a compensation memory. In addition, in normal operation, the external length measuring device is removed. A movement command is input to the input unit and compensated using the error stored in the compensation memory, so that the estimated error is deleted in the normal operation.

Abstract: The present invention relates to a production system (1) for the series manufacture of products, comprising a processing device (2) which, as a function of control commands, actuates a tool for processing one of the products, a measuring device (3) for the automatic measuring of a geometric actual dimension at one of the processed products, a correcting device (4) which is coupled to the processing device (2) and to the measuring device (3) and which compares the actual dimension with a preset target dimension which lies within a tolerance interval. The correcting device intervenes in a corrective manner in the control commands of the tool if the actual dimension lies outside an intervention interval which lies within the tolerance interval.

Abstract: A method for registering machine tool and profilometer coordinates, wherein the machine tool defines a C-axis having a zero position, C=0, comprises loading a sacrificial workpiece into the machine tool; cutting several first features in a surface of the sacrificial workpiece and producing a linear machine tool motion across the workpiece; determining the centroid of each first cut feature; fitting a line to the centroids of the first cut features; and measuring angle ?0 of the line relative to the C-axis zero position. The angle ?0 is the departure in profilometer coordinates from the C=0 line. The method includes moving the machine tool to a fixed radius; cutting several second features in a surface of the sacrificial workpiece and producing a circular machine tool motion across the workpiece; determining the centroid of each second cut feature; fitting a circle to the centroids of the second cut features; and determining a center of the circle.

Abstract: The invention relates to a device for controlling the position for work devices (41) of mobile machines (40). The inventive device comprises a measuring device (1,2) for measuring an angle (?) which is formed between a level (42) that is determined by the position of the work device (41) and the direction of the gravitational force (g). The inventive device also comprises an angle transmitter (5) for predetermining an angle (??) which is formed between a level (42) that is determined by the position of the work device (41) and the direction of the gravitational force (g). The inventive device further comprises a controller (3, 4, 6–16) for controlling the angle (?) between the level (42) of the work device (41) and the direction of the gravitational force (g) in such a way that the measured angle (?) matches the predetermined angle (??).

Abstract: A machine tool having at least one or more spindles that can be positioned in space, the spindle being mounted on displaceable slides by rods and the displacement of the slides leading to the spindle being positioned in space. A correction device is provided which defines the actual position of the spindle relating to one or more reference points.

Abstract: A preset controller which performs preset control, which allows, in the case of updating and correcting a print operational condition for a print pattern number, another print operation for a different print pattern number to reflect the updated and corrected compensator set value. A preset controller of a compensator in a rotary press is provided. The rotary press includes a compensator for use in a paper leading course extending from a printing unit to a folding unit and a movement device for moving the compensator, and controls the movement device so that the compensator is moved to a preset location suitable for cutting a printed web at an optimum position thereof. The preset controller includes a set value reader for reading, based on a paper leading course number read by a data reader, a compensator number and a compensator set value corresponding to the paper leading course number.

Abstract: In a method for making and evaluating a sample cut in an engraving machine, an engraving control signal for guiding a stylus is formed from engraving data. The stylus cuts a series of cups. During a trial engraving trial cups are engraved and a video image is made. In accordance with screen parameters, measuring points are fixed in the video image as distances to a selected reference point. Geometric parameters of the trail cups are measured in the video image and are compared to corresponding geometric parameters of the cups representing predetermined tone values. Adjustment values are deduced from this comparison which are used to calibrate the engraving control signal.

Abstract: A positioner for use in a tooling apparatus, the positioner including a tool, at least one servo-motor for actuating said tool, a controller for controlling the servo-motor, nonvolatile memory in the controller, and a calibration stored in the nonvolatile memory, the calibration including compensation parameters for the build variance of the positioner.

Abstract: A numerically controlled curved-surface machining unit comprises a component converting matrix·angle-addition value forming function of converting CL (cutter location) data into components on a normal coordinate system on the basis of the machine configuration of the simultaneous multiple-axis control NC machine, a component converting function of converting from the workpiece coordinate system to the normal coordinate system, a function of forming second angles of a second rotary axis on the normal coordinate system, a compensating function of forming a continuous angle distribution from a distribution of the second angles, a function of forming first angles of a first rotary axis on a coordinate system rotated by the second angles at the second rotary axis, a compensating function of forming a continuous angle distribution from a distribution of the first angles, a machine coordinate transformation matrix forming function of obtaining a matrix for converting the tool control point vectors on the workpiece c

Abstract: A method for repairing an airfoil comprising creating a nominal numerically-controlled tool path based on a nominal shape of the airfoil, measuring the airfoil using a displacement sensor, capturing differences in the airfoil shape as compared to the nominal shape, creating a three-dimensional map by synchronizing x, y and z coordinates and readings from the sensor, modifying the tool path based on the three-dimensional map, and machining the airfoil. A system for measuring and machining an airfoil comprising a computer operable for data acquisition and numerically-controlled tool path generation, a numerically-controlled machine, a cutting tool holder comprising a plurality of cutting tools, and a displacement-sensing probe.

Abstract: An electrical discharge machining apparatus includes a simulator. The simulator calculates machining information relating to machining shape at each of several simulated machining depths, when the electrode is moved into a workpiece, until an input machining depth is obtained, based on the shape of the electrode input, the shape of the workpiece, and the machining depth of the workpiece, and determines a shape obtained by subtracting the machining shape from the shape of the workpiece, as a new shape of the workpiece, at each simulated machining depth.

Abstract: A position control apparatus and method has been devised which provides for an improved means of suppressing tracking error from a variable position reference occurring when a control object positioned via a transmission mechanism with mechanical transmission error resumes movement from a state stopped at a target position. A selection between two alternative tracking error compensating means within the control apparatus is made based on whether the detected position of the control object changes in a period after the control object stops and before the variable position reference is input again to a control deviation generating unit.

Abstract: A numerical controller capable of driving a controlled axis in synchronism with a reference axis at a desired speed not restricted by a speed of the reference axis in a path table operation and capable of performing auxiliary function, spindle function and tool wearing compensation function, and changing a position of starting the path table operation of the controlled axis. Data tables are provided storing command positions of controlled axes to be associated with positions of the reference axis and for the auxiliary, spindle and tool wearing compensation functions. The number of pulses of a reference pulse signal from the reference axis is counted and multiplied by an override scale factor and the result is stored in a reference position counter. The controlled axes are driven based on command positions of the controlled axes determined based on the reference position counter, referring to the path and function data tables.

Abstract: A device for detecting thermally caused linear expansions of a machine element, wherein the device includes a temperature sensor placed along an expansion direction. The temperature sensor includes a first metallic conductor having an electrical resistance that is proportional to an average temperature of an area to be monitored and a plurality of trimmer tracks in the form of further metallic conductors placed next to the first metallic conductor. The temperature sensor further includes electrical connections selectively interconnecting the plurality of trimmer tracks with the first metallic conductor and wherein the plurality of the trimmer tracks have an effective electrical resistance that is proportional to the average temperature of the area to be monitored.

Abstract: It is strongly demanded that a stable thread machining process be attained by carrying out a thread machining operation while varying the rotational frequency of a spindle, and thereby restraining the occurrence of cutting chatter. According to the present invention, in which a thread machining process is carried out on the basis of a rotation of the spindle and a movement of a feed axis, the above-mentioned demand is met by executing the steps of determining a relative phase error of the spindle positions and feed axis during a thread machining operation, and determining a movement quantity of the feed axis on the basis of a pseudo spindle position set by error-compensating the quantity of the relative phase error with respect to the spindle position.

Abstract: Large machines, especially those having working envelopes in excess of fifteen feet, exhibit unacceptable errors because of thermal expansion and mechanical misalignments between the axes. The errors have traditionally been minimized by enclosing the machine in a thermal enclosure, by careful calibration, or by mounting a laser interferometer on each axis. These solutions are costly, may require frequent recalibration, and do not correct for small rotations of one axis relative to another axis due to wear etc. The present invention uses an interferometric laser tracker or a comparable 3D position sensor to measure the position of a retroreflector attached to the end effector, e.g. a machine head when the machine comes to rest. A computer compares the measured position to the desired position according to the machine media, and adds the appropriate correction with trickle feed media statements to move the machine to the correct position prior to further machining.

Abstract: A machine tool 10 to fashion objects from blocks of material having a material-remover 16 able to move in at least two degrees of freedom and having the material 18 controlled by processing circuitry. The processing circuitry 18 determines a path along which the material-remover 16 should move, allowing the depth of a cut made by the material remover to vary. The movement of the material-remover 16 is so controlled to improve bulk material removal when compared to prior art machines.

Abstract: A numerical control apparatus for machine tool, includes an NC program storage portion for storing an NC program; a transformer means for performing an optimizing process for analyzing the NC program and parameters in the machine tool and transforming the NC program in an optimum condition; an optimized program generated by said transformer means and containing an optimized main program, and optimized data; first and second optimized data storage portions for storing and holding the optimized data. While the machine tool is operated according to the optimized program on the basis of the optimized data stored in the first optimized data storage portion, the transformer means can generate new optimized data on the basis of the NC program and can write a transformed data in the second optimized data storage portions.

Abstract: A gear machining controller capable of performing a gear machining of high precision. A gear machining tool and a workpiece are driven by a first motor and a second motor, respectively, to be synchronized with each other, to perform gear machining on the workpiece such as gear cutting and gear finishing. A position amending section is provided at least one of position control loops of servo systems for controlling position/velocity of the first and second motors. The position amendment section obtains amendment amounts based on position deviations and amends a position command of a present processing period by the amendment amount obtained at the processing period preceding by one cycle period of variation of a load torque. An error of synchronization of the first and second motors is reduced so that the gear machining of high precision is performed.

Abstract: An apparatus for compensating position error of a spindle head, comprises: Y-axis control parts 32a, 32b for controlling first and second servomotors 24a, 24b on the basis of a spindle head moving command fed from a numerical control unit 30; a correction data storage part 36 for storing correction data determining the relationship of a feed distance of a ram 18 to a compensation value for correcting the vertical deviation of the ram 18 in the feed distance of the ram 18; and a correction means 44 for being introduced a ram feed instruction, which is fed from the numerical control unit, and for reading out compensation value corresponding to the feed distance of the ram from the correction data storage unit 36, to correct the spindlehead feed instruction by adding or subtracting the compensation value to or from the spindlehead feed instruction.

Abstract: The present invention is directed to provide a control apparatus for a cutting machine in which offset values on coordinates relative to the cutting machine are indicated, regardless of the position of the turret, and an operator need not calculate the offset values in the cutting process. This invention is characterized in that an X-axis offset value (&Dgr;X) and a Z-axis offset value (&Dgr;Z) of a cutting edge of the cutting tool when the turret 1 has been turned to an arbitrary angle are converted to values on coordinates relative to the cutting machine, and indicated.

Abstract: A method for controlling an automatically operated lathe provided with at least one spindle and at least one tool rest includes the following steps. First, each of a plurality of transfer position data required in a sequence of machining programs in connection with at least one spindle and at least one tool rest is provided in a form of either one of two types of transfer position data, one of which is cam-reference data directing a transfer position as a function of a cam rotation quantity and the other is time-reference data directing a transfer position as a function of an elapsed time. Next, a time-series allocation of the cam-reference data and the time-reference data is designated in the sequence of machining programs. Then, the cam-reference data and the time-reference data are processed in accordance with the time-series allocation, so as to control a relative feed motion between at least one spindle and at least one tool rest in the sequence of machining programs.

Abstract: A method for controlling an automatically operated lathe, provided with at least one spindle and at least one tool rest, includes the following steps. First, each of a plurality of transfer position data required in a sequence of machining programs in connection with at least one spindle and at least one tool rest is provided in a form of a cam-reference data directing a transfer position as a function of a cam rotation quantity. A plurality of pulse-train generating sources, each of which generates any pulse train, is also provided. Next, with regard to each of the plural transfer position data, a pulse-train generating source for generating a pulse train defining the cam rotation quantity as one component of the cam-reference data is designated, with the pulse-train generating source being selected from the plural pulse-train generating sources.

Abstract: There is provided a finite type rolling guide deviation correcting method and system capable of detecting the deviation in relative position between a rolling guide and a movable body if the deviation in relative position increases, and automatically carrying out a correcting operation for returning the deviation in relative position to a normal positional relationship. The finite type rolling guide deviation correcting method corrects a relative positional relationship between a finite type rolling guide for guiding a reciprocating motion of a movable body and the movable body.

Abstract: A drive control system having constituent devices such as control unit for drive control, servo amplifier for driving motor by receiving a command from the control unit, spindle amplifier, and input and output unit, with these constituent devices connected so as to communicate with each other, in which a memory is provided in each constituent device, the constituent devices are synchronized with each other, a communication unit is provided for transferring memory data between arbitrary constituent devices, and the memory is shared between arbitrary constituent devices.

Abstract: The invention relates to a control method and a control device for the operation of rotationally or linearly driven axes with a position control. This involves determining the difference between the setpoint position value (LS) and actual position value (WI) caused by an additional movement component during the time period of the occurrence of at least one superposed movement by subtraction of one value from the other. Furthermore, it is possible to eliminate movement components which are known, periodic and can be mathematically determined as desired from all the required control data paths during the time period of the superposed movement.

Abstract: An apparatus for automatically controlling the work flow of a machine—equipped with effectors (2) driven by rotational motors (12)—comprises: electronic storage means (11) having resident functions that relate the angle of rotation described by a controlling motor (12) with the desired instantaneous position of a controlled effector (2); means (13) for detecting the actual instantaneous position of the controlled effector (2); comparator means (14) for determining the positional error of the controlled effector (2) relative to a given expected position upon reaching a certain angle of rotation of the controlling motor (12); and means (15a) for controlling the motor (12) of the controlled effector (2), which receive the error signal from the comparator means (14) and apply to the motor (12) a corresponding corrective action designed to control and synchronize the angular position of the controlled motor (12) with that of the controlling motor (12).

Abstract: A method for manufacturing a ring (i.e. class, championship, or affiliation) begins by receiving order data specifying a series of personalization elements, such as the addition of text and icon designs. A geometric model for each personalization item is constructed. To assemble text panels, the operating system provides font geometry for a desired TrueType font. Then a set of splines are created from the font geometry and are then tessellated to generate polyline sets of data, which are then spaced and mapped between two boundary curves. The personalization elements are then projected onto one of the model's 3D surfaces. A set of machining instructions for a milling machine is generated by obtaining a set of machining pattern strategies, generating a set of curves, projecting the toolpath onto the surface of the ring to calculate the 3D toolpath, and rotating it to a desired angle.

Abstract: A method and system compensates for vertical deflection for parts manufactured by a numerically controlled (NC) machine. The (NC) machine has an application head position programmed to a plurality of nominal tool coordinates. Each nominal tool coordinate has a horizontal coordinate, a rotational coordinate, and a vertical coordinate. A tool used to manufacture the part is placed on the NC machine. The tool has a plurality of actual tool coordinates, each actual tool coordinate has a horizontal component, a rotational component, and a vertical sag component. A difference between each vertical sag component and a corresponding one of the nominal tool coordinates is calculated. Each difference is multiplied by a multiplier value providing an adjusted sag value. Each adjusted sag value is subtracted from the application head position for each actual tool horizontal or rotational coordinate to compensate the part for the vertical sag of the tool during manufacture.

Abstract: A machining error correction method corrects error in machining of a work by a tool. The method is adapted for a machine tool that includes a numerical control unit in which a movement amount of the tool is programmed and a tool moving unit that is driven by an instruction signal sent from the numerical control unit and feeds the tool to the work fixed on a work table. The method includes the steps of moving the tool from a program origin to a measurement point provided separately from the program origin by giving a predetermined measurement movement amount to the tool moving unit from the numerical control unit; measuring a positional deviation amount between the measurement position and a tool position after the movement is finished; and correcting a machining movement amount of the tool moving unit using the positional deviation amount when the work is machined.

Abstract: A positioning device and method can position a subject of positioning at a higher speed than conventional ones. A positioning device and method for moving a subject of positioning to a desired position, moves the subject of positioning at a desired speed and acceleration, and adjusts the acceleration/deceleration duration of the subject of positioning and the timing of starting the deceleration so as to cancel the residual vibration, in accordance with the vibration period of the residual vibration that occurs immediately after positioning the subject of positioning.

Abstract: A profile data compensating method comprises a step of generating effective profile data by operating a machine tool under a non-load condition in accordance with theoretical profile data, a step of generating first error profile data representing error components of a control system, a step of generating first compensated profile data based upon the first error profile data, a step of generating measured profile data by measuring the shape of the workpiece machined in accordance with the first compensated profile data, a step of generating second error profile data representing error components of a mechanical system, and a step of generating second compensated profile data based upon the first and second error profile data.

Abstract: A lost motion correction value setting method for a machine tool of a hybrid control system that performs a positional loop control with both machine position signals outputted from position detecting scales for detecting machine positions and motor position signals outputted from rotary encoders for detecting a rotational angle of a feed driving servomotor includes executing a test program; periodically inputting the machine position signals outputted from the position detecting scale and the motor position signals outputted from the rotary encoder; determining errors by determining the difference between the machine position signals and the motor position signals, determining the difference between an average value on an advance side and an average value on a return side of the errors, and storing the difference in lost motion correction value memories as a dynamic lost motion correction value.

Abstract: For a number of different operating points in a workspace of a processing machine, the total length changes caused by a weight force are determined and entered together with the corresponding set points in a compensation table. The compensation values are used to compute control variables for set points. Values for intermediate points are interpolated from the values stored in the compensation table. This eliminates positioning errors at both the predetermined operating points and the intermediate points. Advantageously, the changes in the length can be determined from the motor force that counteracts the force acting on the corresponding actuator in a static state, based on an instantaneous nominal current value and/or actual current value of the motor.

Abstract: Method and system for a direct transmission of motion path data (310) from a generating system (204) to a control system (205) for use in controlling a servo-driven machine. For example, a machine tool for machining stock material, and the data generating system includes a computer-aided-design software package (301). Tool paths for directing the tool members of the machine tool can be extracted from a design file opened by the CAD software through the operation interface of the CAD software (302). Alternatively, the design file can be used to specify motion paths rather than end product geometry. The CAD interpreter application extracts the motion path data from the design file, eliminating the need to translate the data into another or intermediate form for controlling the machine tool.

Abstract: A position measuring device that includes a first element having a material measure and a temperature measuring unit with a sensor, the temperature measuring unit is unable to be displaced relative to the material measure. A second element having a scanning head, and an electronic correction device that determines a temperature-corrected position value, wherein the first element is displaced in relation to the second element.

Abstract: The present invention relates to a control method and a control apparatus for controlling two (two kinds of) driver mechanisms for relatively moving a main spindle along a single axis in an NC machine tool whereby the straightness of the work-piece machined surface can be finished with high accuracy. The control method of the invention controls operations of two driver mechanisms (124,125,126) for relatively moving a main spindle (104) along a single axis in an NC machine tool (100), and one of the driver mechanisms (124 or 125,126) is driven to relatively move the main spindle (104) in a positive direction along the axis during machining, the other driver mechanism (124 or 125,126) is driven to relatively move the main spindle (104) in a negative direction along the axis during machining.

Abstract: Large machines, especially those having working envelopes in excess of fifteen feet, exhibit unacceptable errors because of thermal expansion and mechanical misalignments between the axes. The errors have traditionally been minimized by enclosing the machine in a thermal enclosure, by careful calibration, or by mounting a laser interferometer on each axis. These solutions are costly, may require frequent recalibration, and do not correct for small rotations of one axis relative to another axis due to wear etc. The present invention uses an interferometric laser tracker or a comparable 3D position sensor to measure the position of a retroreflector attached to the end effector, e.g. a machine head when the machine comes to rest. A computer compares the measured position to the desired position according to the machine media, and adds the appropriate correction with trickle feed media statements to move the machine to the correct position prior to further machining.

Abstract: The servo control method operates a set value of a first-order lag time constant of a feedback compensation by both a detected mechanical position value and a transfer function corresponding to a change of an angular velocity about each axis under a multiple-axes simultaneous control. Further, the servo control method sets a feedforward amount so that the transfer function about the each axis is the same.

Abstract: In the movable shaft (32) constructed by a plurality of motion modules (31), since the moving command based on the machining program (1) in unit of the movable shaft like the prior art is converted into moving commands of the motion modules (31) to control this movable shaft (32), the machining can be executed if the machining for the movement of the movable shaft is defined like the machining program in the prior art. Also, assignment of a plurality of motion modules (31) to the movable shaft (32) can be set arbitrarily and then the pulse distribution to the movable shaft (32) is executed in response to this assignment. In addition, if the failure is caused in the motion module (31), such motion module (31) can be disconnected.

Abstract: A system for adapting existing conventional screw machines to be capable of computer numerical control operation. The system incorporates the use of a VersaCam device which replaces the turret cam of a single spindle screw machine. The VersaCam system monitors the motion of the screw machine camshaft and actuates the turret slide in synchronization with the camshaft. The VersaCam system also provides a means of specifying the desired turret slide trajectory for any given job.

Abstract: A method of nesting a computer model of a part (100) into a computer model of a fixture (104) useful for situations where the original positions of the part and fixture are completely separate and for situations where the respective part and fixture surfaces overlap. The model of the fixture is first inset by a distance D sufficient to eliminate any overlap between the modeled surfaces. The minimum normal distance segment (105) between the inset fixture surface and the part surface may then be determined using standard CAD system capabilities. A vector is then constructed having a length D beginning at the minimum distance point 111 on the inset fixture surface (107) and extending in the direction of the minimum normal distance segment (105) to a point (112) on the original fixture model surface (106). The minimum distance segment between point (112) and the surface of the part (102) is then determined to identify a point (114). The respective point pair (112,114) is recorded.

Abstract: A method and apparatus by which accurate correction values for thermal displacement is calculated even when the rotation of the main spindle is restarted after interruption. The apparatus has means 2, 3 for measuring the temperature near the main spindle 15, means 5 for estimating the thermal displacement of the main spindle 15 on the basis of the measured temperature and a predetermined thermal displacement calculation expression, means 7 for calculating the correction value, and means 6 which estimates the displacement delay in re-rotation caused by the interruption of the rotation of the main spindle 15, and calculates an adjusting displacement on the basis of the estimated displacement delay. The correction value calculating means 7 calculates a correction value on the basis of the thermal displacement estimated by the thermal displacement estimating means 5 alone when the main spindle 15 is started up and rotated.

Abstract: Provided is a machining error correction method adapted for a numerically controlled machine tool, with which a fluctuation in an actual feed amount of a tool resulting from an influence of a fluctuation in the environmental temperature, frictional heat at the time of machining, and the like is eliminated so that it is possible to machine a work with a high degree of precision without comparing the work with a master using a sizing device. The machine tool includes a numerical control unit in which a movement amount of the tool is programmed, and a tool moving unit for positioning the tool. The numerical control unit gives a predetermined measurement movement amount to the tool moving unit.

Abstract: A power feeder (10) includes a flexible strip (12) having a conducting front side (12a) and an insulating back side (12b); a retainer unit (20) for holding the strip wrapped on a bar (18) with the back side being in close contact with the bar; a feeder unit (22) connected electrically with the front side of the strip; and a base (26) mounted detachably on the headstock (24) of an automatic lathe. A tool-positioning device (14) including this power feeder includes a driving unit (60) for bringing a tool (56) to be positioned into contact with the front side of the strip; a section (62) for detecting a conduction between the tool and the front side of the strip through the feeder unit to determine the position of contact with the tool; and a corrective processing section (64) for determining the position of a center axis (18a) of the bar based on the position of the determined position of contact with the tool.

Abstract: A method of guiding a tool for machining a work piece of a material block, the material-removing work portion of the tool being guided to move along a first guide path while a further point on the axis of the tool, which is located at a distance from the work portion, is guided along a prescribed second guide path, whereby the five kinematic coordinates of the movement of the tool are fully determined.