Jtekt Corporation

Toyoda Koki Kabushiki Kaisha

Kikutoshi Okada

Masahiro Ido

Shoichi Sano

Hisayuki Nagaya

Shinji Deguchi

Dai Kiyota

Teruhiro Nakamura

Eiji Fukuta

Shinji Nishio

Hidetaka Sugiura

Toshiaki Naya

Hiroaki Kikuchi

A grinding machine includes a manual rotating handle provided with a rotation detector that outputs a rotation detection signal so that the position of a grinding wheel with respect to a workpiece can be relatively moved in accordance with the rotation detection signal. The grinding machine further includes a grinding wheel, a moving apparatus that moves the position of the grinding wheel with respect to a workpiece W, a proximity detector that outputs a proximity detection signal corresponding to a relative position or a relative distance between the workpiece and the grinding wheel, a manual rotating handle provided with a rotation detector, and a control apparatus that controls the moving apparatus based on the rotation detection signal. The manual rotating handle is provided with a rotational-torque varying apparatus. The control apparatus controls the rotational-torque varying apparatus based on the proximity detection signal.

Grinding machine

A grinding method includes the steps of holding a workpiece by a pair of centering members of a pair of spindle equipment, shifting two centering members to one side of a spindle rotational axis, facing a grinding wheel at the other side to the other end portion of the workpiece, grinding the other end portion of the workpiece by the grinding wheel at the other side by rotating a driving pin of the spindle equipment at one side, retracting the grinding wheel at other side and stopping the rotation of the driving pin at one side and also shifting two centering members to the other side of the spindle rotational axis, facing a grinding wheel at one side to one end portion of the workpiece, and grinding one end portion of the workpiece by the grinding wheel at one side by rotating a driving pin of the spindle equipment at the other side.

Grinding method of multifunction grinding machine

A first angular grinding wheel and a straight grinding wheel having rotation axes parallel to each other are arranged on a swivel slide that turns about a turning axis. A reference symmetry plane (MA) that is parallel to a grinding wheel rotation axis and that includes the turning axis and a reference perpendicular plane (MB) that is perpendicular to the reference symmetry plane and that includes the turning axis are defined. A grinding reference point (PA) of the first angular grinding wheel (TA) and a grinding reference point (PP) of the straight grinding wheel (TP) are arranged asymmetrical with respect to the reference symmetry plane. A distance from the grinding reference point of the straight grinding wheel to the reference symmetry plane is equal to a distance from the grinding reference point of the first angular grinding wheel to the turning axis.

It is an object of the present invention to provide a bed of a machine tool to be stably leveled and supported by three support points and to reduce the strain of the bed of which structure is simplified. The bed of the machine tool according to the present invention comprises three props and a ceiling. The props are arranged as a triangle. The ceiling is put on the props and supports at least one tool box and work saddle. In the triangle in view of horizontal plane, there exists center of gravity of the whole machine tool.

Machine tool and bed thereof

A method for measuring the diameter and eccentricity of a crankpin of a crankshaft which is ground on a grinding machine. A reference plate is provided on a headstock, which is disposed on a table to support the crankshaft. A measurement apparatus having a probe is disposed on a wheel head. Through movements of the table and the wheel head, the probe is first brought into contact with a reference surface of the reference plate, and is then brought into contact with the outer circumferential surface of the crankpin at outermost and innermost points. The distances between the reference surface and the outermost and innermost points are measured, and the diameter and eccentricity of the crankpin are calculated on the basis of the measured distances and the position of the reference surface.

Method for measuring work portion and machining method

On a grinding machine, a workpiece having eccentric cylindrical portions is rotated around the work spindle axis so that the eccentric cylindrical portions effects a planetary motion. A grinding wheel is reciprocated toward and away from the work spindle axis in synchronism with the planetary motion and is also fed toward the work spindle axis to grind the eccentric cylindrical portion into a target cylindrical profile. Upon completion of a part of the grinding operation, the eccentric cylindrical portion under machining is indexed to a predetermined angular position. A diameter measuring device is moved from its rest position to a measuring position to measure the diameter of the eccentric cylindrical portion. Comparing the measured diameter with a target diameter to obtain a residual difference in diameter, the grinding machine further operates to perform a finish grinding according to the residual difference until the diameter reaches the target size, whereby the eccentric cylindrical portion can be finished precisely using a general purpose measuring device.

Growing community of inventors

Kariya, Japan

Kikutoshi Okada