Numerical control device

Patent metadata

Field	Value
Publication number	US-2016266567-A1
Application number	US-201414649992-A
Country	US
Kind code	A1
Filing date	Apr 23, 2014
Priority date	Apr 23, 2014
Publication date	Sep 15, 2016
Grant date	—

Abstract

A numerical control device includes a phase-difference calculation unit that, when machining with vibrations is performed on a movement path, calculates a phase difference between a vibrational forward-moving position and a vibrational backward-moving position from a vibration amplitude-to-feed ratio between amplitude of the vibrations and a feed speed of a tool to a workpiece, a movement-path generation unit generating the vibrational forward-moving position and the vibrational backward-moving position as the movement path for each drive shaft by using the phase difference, a vibration-waveform generation unit generating a reference vibration waveform to be superimposed on the movement path for each drive shaft by using vibration conditions, a vibrational-movement-amount generation unit calculating a vibrational-movement amount on the movement path for each drive shaft by using the reference vibration waveform, and a movement-amount combining unit generating a combined movement amount for each drive shaft by adding the vibrational-movement amount to the movement path.

First claim

1 . A numerical control device that performs machining on a workpiece while moving a tool and the workpiece relative to each other along a movement path with vibrations by drive shafts with which the tool or the workpiece is provided, the device comprising:
a phase-difference calculation unit that calculates, as a phase difference, a time lag in a vibrational backward-moving position relative to a vibrational forward-moving position generated on a basis of a command block in a machining program from a ratio between an amplitude of the vibrations and a feed speed of the tool to the workpiece, the ratio being designated for the movement; a movement-path generation unit that generates the vibrational forward-moving position and the vibrational backward-moving position as the movement path for each of the drive shafts on a basis of the phase difference; a vibrational-movement-amount generation unit that calculates a vibrational-movement amount on the movement path for each of the drive shafts on a basis of a reference vibration waveform to be superimposed on the movement path; and a movement-amount combining unit that generates a combined movement amount for each of the drive shafts by adding the vibrational-movement amount to the movement path.

2 . The numerical control device according to claim 1 , wherein when the movement-path generation unit generates movement paths in command blocks different from each other in a machining program, the movement-path generation unit generates each of the movement paths using the ratio.

3 . The numerical control device according to claim 1 , further comprising a feed-speed changing unit that changes the feed speed, wherein
the movement-path generation unit generates the movement path using the ratio and the feed speed changed by the feed-speed changing unit.

4 . The numerical control device according to claim 1 , wherein the ratio is set such that, when a first axial position on a movement path at a time when a main shaft that rotates the workpiece is at a predetermined rotation phase and a second axial position on a movement path at a time when the main shaft is at the rotation phase after rotating by one or more revolutions are compared with each other, a rotation phase at which the first axial position is located closer to a movement start point than the second axial position in an advancing direction and a rotation phase at which the second axial position is located closer to the movement start point than the first axial position in an advancing direction are present.

5 . A numerical control device that performs machining on a workpiece while moving a tool and the workpiece relative to each other along a movement path with vibrations by drive shafts with which the tool or the workpiece is provided, the device comprising:
a movement-path generation unit that generates a vibrational forward-moving position, generated on a basis of a command block in a machining program, and a vibrational backward-moving position, obtained by adding a phase difference designated for the movement to the vibrational forward-moving position, as the movement path for each of the drive shafts; a vibrational-movement-amount generation unit that calculates a vibrational-movement amount on the movement path for each of the drive shafts on a basis of a reference vibration waveform to be superimposed on the movement path; and a movement-amount combining unit that generates a combined movement amount for each of the drive shafts by adding the vibrational-movement amount to the movement path.

6 . The numerical control device according to claim 5 , wherein when the movement-path generation unit generates movement paths in command blocks different from each other in a machining program, the movement-path generation unit generates each of the movement paths using the phase difference.

7 . The numerical control device according to claim 5 , further comprising a feed-speed changing unit that changes a feed speed of the tool to the workpiece, wherein
the movement-path generation unit generates the movement path using the phase difference and the feed speed changed by the feed-speed changing unit.

8 . The numerical control device according to claim 5 , wherein the phase difference is set such that, when a first axial position on a movement path at a time when a main shaft that rotates the workpiece is at a predetermined rotation phase and a second axial position on a movement path at a time when the main shaft is at the rotation phase after rotating by one or more revolutions are compared with each other, a rotation phase at which the first axial position is located closer to a movement start point than the second axial position in an advancing direction and a rotation phase at which the second axial position is located closer to the movement start point than the first axial position in an advancing direction are present.

Assignees

• Mitsubishi Electric Corp
• Citizen Holdings Co Ltd
• Citizen Machinery Co Ltd

Inventors

• Watanabe Mitsuo
• Sagasaki Masakazu
• Hirata Yuki
• Matsumoto Hitoshi

Classifications

• B23Q15/013

  Control or regulation of feed movement (B23Q15/12 takes precedence) · CPC title

• G05B2219/50047

  Positioning, indexing · CPC title

• G05B2219/50049

  Control machine as function of position, angle of workpiece · CPC title

• G05B19/19 Primary

  characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path · CPC title

• G05B19/4103 Primary

  Digital interpolation · CPC title