Toyoda Koki Kabushiki Kaisha

Yoichi Yamakawa

Kazuhiko Sugita

Nobumitsu Hori

Norio Sakakibara

Toshihiro Takahashi

Shigeo Hotta

Akira Ito

Hiroaki Asano

Kunihiko Unno

Yasuhiro Kobayashi

Osamu Matsuda

Tetsuro Shibukawa

Taizo Toyama

Hiromichi Ohta

Hirotaka Sugiura

Hiroyoshi Suzuki

A machine tool of the present invention includes a base fixed to an outside fixed portion, a travelling plate to which a tool is to be attached, plural guide portions radially outwardly fixed to the base at a predetermined angle, and plural rods. Each of the plural guide portions is provided with a slide table movable in a longitudinal direction of the guide portion and an actuator for moving the slide table. One end of each rods is connected with one of the slide tables through first joint means and another end of each of the rods is connected to the traveling plate through second joint means.

Machine tool having parallel structure

An apparatus for detecting contact between a contact detection member and a rotating body such as a grinding wheel rotably carried on a wheel head which is movable toward the contact detection member in a grinding machine for example. The apparatus comprises an AE sensor, a rectangular pulse generator, a sampling circuit and a processing device such as a microcomputer. The AE sensor generates an electric signal in response to vibration of the contact detection member. The rectangular pulse generator outputs a rectangular pulse whose duration corresponds to that of vibration. The sampling circuit delivers to the processing device an output indicating the duration of the rectangular pulse. The processing device processes the output delivered thereto so as to decide the occurrence of an actual contact between the rotating body and the contact detection member.

Apparatus for detecting contact with rotating body

A device for detecting a position of an edge of a cutting tool includes a reference plate positioned to form a slit between the edge of the cutting tool and the reference plate. The slit extends in a direction transverse to the longitudinal direction of the cutting tool. A laser light source is provided to irradiate a laser light to the slit. A detecting device detects a diffraction pattern created through diffraction of the laser light by the slit. A processing device is provided to determine the position of the edge of the cutting tool based on an output signal of the detecting device.

Device and method for detecting position of edge of cutting tool

An apparatus for machining a non-circular workpiece such as a piston wherein a tool is moved back and forth against the workpiece in accordance with profile data defining a desired final shape of the workpiece while the workpiece is rotated at a predetermined speed. The tool is moved by a composite movement of a linear motor driven in accordance with low frequency command values, and a piezoelectric actuator driven in accordance with high frequency command values. A numerical controller of the apparatus calculates the low frequency command values using a first Fourier series and the high frequency command values using a second Fourier series. Coefficients of the first and second Fourier series are determined using least square method in such a way that errors contained in the low and high frequency command values becomes within a predetermined limit.

Method and apparatus for machining a non-circular workpiece

An apparatus for machining a non-circular workpiece, wherein the profile data of plural sections of the workpiece stored in the profile data storage means are transformed into the frequency functions of 1 to n degree which is a function of the rotary angular velocity of the workpiece. The calculation means finds the amplitudes and the phases of each degree of the frequency function of each of plural intermediate sections by means of the interpolation according to the position between selected two sections based on the frequency functions of the selected two sections so as to obtain high frequency functions and low frequency functions which are then converted to high frequency and low frequency profile data. The machining apparatus actuates a linear motor in accordance with the high frequency profile data and actuates a PZT actuator in accordance with the low frequency profile data. The actuations of these actuators are accomplished in a synchronized relationship with the rotation of the workpiece to machine the workpiece into a non-circular shape whose sectional shape changes with respect to its axial position.

Apparatus for machining a non-circular workpiece

An apparatus for machining a non-circular workpiece wherein a tool is moved by a composite movement given by a linear motor and a piezoelectric actuator. The linear motor is driven by the numerical controller in accordance with the low frequency components of profile data defining a position change of the tool with respect to angular position change of the spindle, while the piezoelectric actuator is driven by the numerical controller in accordance with the high frequency components of the profile data. Further, a positioning error of the tool due to reaction force generated by the piezoelectric actuator is detected by the numerical controller to compensate the high frequency components for the detected positioning error.

An apparatus which moves a tool back and forth in synchronism with rotation of a workpiece with respect to the workpiece to machine the workpiece into a non-circular shape. The tool is attached to a tool mount placed on a tool mount table which is connected to be moved in a direction perpendicular to the axis of a spindle by a motor. The tool is connected to be moved in a direction perpendicular to the axis of the spindle with respect to the tool mount by a high speed actuator. Profile generating movement of the tool is thus provided by a combination of movement provided by the motor and movement provided by the high speed actuator. The high speed actuator is controlled in accordance with high frequency components included in profile data while the motor is driven in accordance with low frequency components included in the profile data. As a result, the responsiveness in profile generating movement of the tool is improved, and high speed machining of a non-circular workpiece is enabled.

A positioning controlling device for improving the machining accuracy of a work of a non-circular shape. A control axis is driven in accordance with an input function consisting of position instruction data corresponding to a machining shape of a work, and a response function of the position of the control axis is measured actually. Then, a transfer function of the servo system is determined from Fourier transformation of the input function and Fourier transformation of the response function, and a corrected input function with which a response function of the control axis ideally corresponds to the machining shape of the work is obtained from the transfer function. Even if the control axis is driven in accordance with the corrected input function, a response function obtained does not correspond to the ideal machining shape of the work. Therefore, the calculations for obtaining an input function described above are sequentially executed until a response function obtained converges to the ideal machining shape. As a result, even if the servo system has a non-linearity, if the control axis is controlled in accordance with an input function finally obtained in this manner, then a response function then corresponds to the ideal machining shape.

Positioning controlling device

A method and a system for recognizing the location of a cylindrical shaft is provided for use in positioning an end effector of an industrial robot which handles said shaft. In the method and system, a multilevel gray image of the cylindrical shaft which is generated by a change coupled device (CCD) image sensor is first differentiated, and the absolute values of picture elements constituting the differentiated gray image are then binarized on the basis of a threshold value so as to extract an accentuated pattern image which is inherent to the shape of the cylindrical shaft. The accentuated pattern image thus extracted is then collated with a reference accentuated pattern image (template) so as to generate a normal curve signal which has its peak point at a position where the axis of said cylindrical shaft is located. The normal curve data is then binarized on the basis of another predetermined threshold value to generate a single strip image. The center of the single strip image is calculated to determine the location of the cylindrical shaft.

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Aichi, Japan

Yoichi Yamakawa