Mitsubishi Heavy Industries Limited

Mitsubishi Heavy Industries Machine Tool Co., Ltd.

Nidec Machine Tool Corporation

Masashi Ochi

Yoshikoto Yanase

Yasuhiro Nakamichi

Hiroshi Gunbara

Provided is an internal gear grinding method that makes it possible to grind an internal gear having arc-shaped teeth in a short amount of time. To this end, an internal gear having arc-shaped teeth and a threaded grindstone with a barrel shape having blades with a shape corresponding to the arc shape of the teeth are engaged at a predetermined axis intersection angle, and the internal gear and the threaded grindstone are made to rotate in synchronization with each other so that the tooth surface of the internal gear is ground by the blade surface of the threaded grindstone.

Internal gear grinding method

An internal gear machining method and an internal gear machining device, are provided for grinding of a tooth profile of an internal gear using a barrel-shaped threaded grinding wheel. An NC device functions as a tooth profile error correction means and reduces a measured pressure angle error of a workpiece at a tooth face by correcting the radial position, the lateral position of the grinding wheel, the turning angle of the grinding wheel, and the helical motion; reduces a measured error in the direction of a tooth trace of the workpiece at a tooth face by correcting the helical motion; and reduces a measured tooth thickness error of the workpiece at a tooth face by correcting the radial position, the lateral position of the grinding wheel, and the helical motion.

Internal gear machining method and internal gear machining device

Provided is a clamping device having improved safety and an improved clamping force for clamping a work to an attaching table, said work having the inner circumferential surface thereof to be processed. The clamping device clamps a work () disposed on the reference surface () of an attaching table (). The clamping device is provided with: a board-like fixing member (), which has formed therein a hole () that is larger than the inner diameter (D) of the work () but smaller than the outer diameter (D) of the work, and which is in surface-contact with the end surface () of the work () disposed on the reference surface () of the attaching table (); and a pressing force applicator (), which has a cylindrical shape that surrounds the attaching table (), and which applies a pressing force toward the end surface () of the work () with respect to the fixing member ().

Clamping device having ring shape with hydraulically down force clamping means

A method is disclosed for dressing a tool used for machining an internally toothed gear. The method includes meshing an internally toothed gear-like dressing gear, which is rotatable about the dressing gear rotation axis, with a barrel-shaped, screw-like grindstone. For machining an internally toothed gear, the outer diameter of the screw-like grindstone after dressing is estimated before dressing, the angle of intersection between a dressing gear rotation axis and the screw-like tool rotation axis is set on the basis of the estimated outer diameter of the screw-like grindstone after dressing, and dressing is performed with the dressing gear and the screw-like grindstone meshed with each other at the set angle of intersection between the axes.

Method for machining internally toothed gear and method for dressing tool used for same

A method for manufacturing a screw-shaped tool for grinding a face gear with high precision. The tool is formed in such a manner that the diameter thereof gradually increases from an axial end to an intermediate section in the axial direction, and is used for cutting a face gear. The method includes setting up, on the basis of a prescribed pinion which is to mesh with the face gear to be machined, a virtual gear that is to mesh with the prescribed pinion, and has a greater number of teeth than the prescribed pinion; setting up, on the basis of the virtual gear, a virtual inner gear which has the same number of teeth as the virtual gear, said teeth being on the inside; and setting up, on the basis of the virtual inner gear, a screw-shaped grindstone having various elements that are used for cutting the virtual inner gear.

Method for manufacturing screw-shaped tool

Provided is a method of making a barrel-shaped worm-like tool whereby a barrel-shaped worm-like tool capable of efficiently performing grinding without unequal wear can easily be made. The aforementioned method comprises making the barrel-shaped worm-like tool () by using a dressing gear () to dress the barrel-shaped worm-like tool (), which is used for machining an internal gear and has a diameter that gradually increases from the ends () to the center () in the axial direction. On the basis of data wherein the number of teeth is less than that of the internal gear to be machined, the dressing gear () and the barrel-shaped worm-like tool () are engaged with each other at the same axial intersection angle as during gear-machining performed by the barrel-shaped worm-like tool ().

Method of making barrel-shaped worm-like tool

Provided is a gear grinding method capable of improving processing accuracy and easily adjusting the crowning shape by simplifying a processing operation. To this end, a work piece (W) is ground by a gear-shaped grinding stone () having a drum shape such that crowning along a tooth trace direction is applied to the work piece (W) by applying a relative feed in a feed direction (D) that intersects a work piece rotation axis (C) at a predetermined first diagonal angle (&#x3b8;1) between the work piece (W) and the gear-shaped grinding stone () while the work piece (W) and the gear-shaped grinding stone () are synchronously rotated in the state of being engaged so as to have a predetermined crossed axes angle (&#x3a3;), and the curvature in a grinding stone width direction, which defines the drum shape of the gear-shaped grinding stone (), and the first diagonal angle (&#x3b8;1) are set according to the crowning shape of the work piece (W).

Gear grinding method

Disclosed is a method for dressing a threaded grinding stone for internal gear grinding, by which a threaded grinding stone for grinding an internal gear can be dressed with a high degree of accuracy by using a dressing gear that has been produced with a high degree of accuracy. In a state in which a barrel-shaped threaded grinding stone (), which is disposed at an axial angle (&#x3a3;) to the internal gear (W) that is conferred during the grinding of said internal gear (W), and an external tooth-type dressing gear (), which is capable of meshing with a virtual external gear () virtually formed in a manner so as to mesh with the internal gear (W) in place of the threaded grinding stone () disposed at the axial angle (&#x3a3;), have been meshed together, the threaded grinding stone () and the dressing gear () are simultaneously rotated while being moved relatively in a circular arc in the X-Y plane, whereby the dressing gear () dresses along the entire area in the axis direction of the threaded grinding stone ().

Method for dressing threaded grinding stone for internal gear grinding

An object is to provide an internal gear grinding machine and a dressing method for a barrel-shaped threaded tool which make it possible to achieve space savings and reduce the size of a machine by simplifying dressing operation. To achieve the object, an internal gear grinding machine for use in grinding a workpiece (W) by synchronously rotating the workpiece (W) and a barrel-shaped threaded grinding wheel () in mesh with each other includes a dressing device () for dressing the threaded tool () by meshing the threaded grinding wheel () with a disk dresser (). At the time of dressing, the threaded grinding wheel () and the disc dresser () are operated in accordance with the helix angle and the barrel shape of the threaded grinding wheel ().

Internal gear grinding machine and dressing method for barrel-shaped threaded tool

Provided is an internal gear machining method capable of achieving improvement of machining accuracy and extension of the tool life by increasing a slip velocity. For this purpose, internal gear machining is performed on a workpiece (W) by synchronously rotating the workpiece (W) and a barrel-shaped threaded grinding wheel () in mesh with each other. The workpiece (W) is rotatable about a workpiece rotation axis (C), and the barrel-shaped threaded grinding wheel () is rotatable about a grinding wheel rotation axis (B) having a predetermined shaft angle (&#x3a3;) to the workpiece rotation axis (C). In the internal gear machining method, the shaft angle (&#x3a3;) is set large based on the amount of change in a grinding pitch wheel pitch radius of the threaded grinding wheel ().

Internal gear machining method

Provided is a gear grinding machine the maintainability of which can be improved and which is capable of being miniaturized. More specifically, provided is a gear grinding machine wherein a threaded grinding stone () and a workpiece (W) are engaged with each other and are rotated in this state, resulting in the workpiece (W) being ground, and wherein between a dressing position (P) where the threaded grinding stone () can be dressed and a retreat position (P) to which a retreat is made from the dressing position (P) during grinding, a disk dresser () which, by being driven into rotation, dresses the threaded grinding stone () is swung about an axis (C) which is parallel to an axis (C) that is the rotational axis for the workpiece (W) and which intersects, at right angles, the direction in which the threaded grinding stone () is fed toward the workpiece (W).

Gear grinding machine

An object is to provide a barrel-shaped threaded tool for machining an internal gear which is capable of machining with high accuracy by appropriately setting a helix angle. To achieve the object, in a threaded grinding wheel () formed into a barrel shape having a diameter gradually decreasing from an axially intermediate portion thereof toward axially opposite end portions thereof so that the threaded grinding wheel () is meshed with a workpiece (W) with a crossed axes angle (&#x3a3;) therebetween during the machining of the workpiece (W), the helix angle is set in accordance with the length from the axially intermediate portion.

Barrel-shaped threaded tool for machining internal gear

An internal gear grinding machine achieves space savings and reduction in size of a machine, as well as prevents the tools from being damaged even when an abnormal situation such as a blackout occurs, by a simplifying dressing operation. The internal gear grinding machine for grinding a workpiece (W) by synchronously rotating the workpiece (W) and a barrel-shaped threaded grinding wheel () in mesh with each other includes a dressing device () for dressing the threaded tool () by meshing the threaded grinding wheel () with a disk dresser (). When dressing, the threaded grinding wheel () and the disc dresser () are operated in accordance with the helix angle and barrel shape of the threaded grinding wheel (), and the brake mechanism () applies a braking force to a dresser turn drive motor () to enable the disc dresser () to be maintained at a turned position thereof.

Internal gear grinding machine

In a method of dressing a barrel worm-shaped tool, a disc-shaped disc dresser () meshes with a barrel worm-shaped grinding wheel () having its diameter gradually increasing from the two end portions in the axial direction thereof towards the middle portion thereof and used to grind an internal gear (). The barrel worm-shaped grinding wheel () rotates around a tool-rotating shaft (B) disposed at a predetermined shaft angle (A) with a vertical work-rotating shaft (C) for the internal gear (). The disc dresser () rotates around a dresser-rotating shaft (D), the disc dresser () being disposed at an angle equal to a helix angle of the internal gear (). While the barrel worm-shaped grinding wheel () and the disc dresser () mesh with each other and are rotating, the barrel worm-shaped grinding wheel () and the disc dresser () revolve relative to each other within a horizontal plane.

Method of dressing barrel worm-shaped tool, dressing apparatus, and internal-gear grinding machine

To provide a barrel worm-shaped tool capable of grinding processing in high precision, while maintaining the reduction of heavy load during the processing and partial wear. For this purpose, a barrel worm-shaped tool that is used in the gear machining of an internal gear () is formed with its diameter gradually increasing from the two end portions in the axial direction thereof towards the middle portion thereof. The barrel worm-shaped tool () is formed so that edge shapes () of the grinding wheel () becomes gradually smaller from the edge shape () located in the middle portion, in the axial direction of the barrel worm-shaped tool () towards the edge shape () located in the two end portions, in the axial direction, of the barrel worm-shaped tool () in accordance with the amount of machining allowance for the internal gear ().

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Tokyo, Japan

Masashi Ochi