Title:
METHOD FOR CORRECTING THERMAL EXPANSION OF FEED SCREW
Document Type and Number:
Japanese Patent JPH02144605
Kind Code:
A
Abstract:
PURPOSE:To prevent positioning accuracy from being deteriorated by feeding back a correcting variable for correcting a positioning shear due to the operated expansion value of a ball screw to a numerical control command input. CONSTITUTION:Heat generated by a motor 10 is transmitted to the ball screw 20 through a joint means 16 to generate the thermal expansion of the ball screw 20. A correcting factor is previously set up by an experiment including the heat transmission characteristics of an individual machine system of a heat transmission route such as the joint means 16 and a heating value to be directly transmitted to the ball screw 20 and the thermal expansion of the screw 20 due to the heating value are operated. The feeding operation error value of a feed screw mechanism 18 corresponding to the thermal expansion, i.e. a positioning error of an object to be fed such as a table 24 is operated, detected and fed back to an addition point 34 as an error to be corrected. Consequently, the positioning error of the feed screw mechanism 18 is corrected and the positioning accuracy can be improved.
Inventors:
IWAMATSU NOBORU
ENDO YUICHI
ENDO YUICHI
Application Number:
JP29719988A
Publication Date:
June 04, 1990
Filing Date:
November 26, 1988
Export Citation:
Assignee:
FANUC LTD
International Classes:
G05D3/12; (IPC1-7): G05D3/12
Domestic Patent References:
| JPS60228055A | 1985-11-13 | |||
| JPS57114340A | 1982-07-16 | |||
| JPS5367084A | 1978-06-15 |
Attorney, Agent or Firm:
Aoki Akira (4 outside)