Numerical controller for controlling tapping

• US 10,459,424 B2
• Filed: 11/20/2017
• Issued: 10/29/2019
• Est. Priority Date: 11/21/2016
• Status: Active Grant

• Current Assignee: Fanuc Corporation
• Original Assignee: Fanuc Corporation
• Inventors: Watanabe, Tooru, Kubota, Tooru
• Primary Examiner(s): Von Buhr, M.N.
• Application Number:
  US15/817,790
• Publication Number:
  US 20180143612A1
• Time in Patent Office: 708 Days
• CPC Class Codes: G05B 19/186 Generation of screw- or gearlike surfaces
• CPC Class Codes: G05B 19/402 characterised by control arrangements for positioning, e.g. centring a tool relative to a hole in the workpiece, additional detection means to correct position G05B19/19 takes precedence
• CPC Class Codes: G05B 2219/31455 Monitor process status
• CPC Class Codes: G05B 2219/45216 Tapping

Abstract

Provided is a numerical controller capable of shortening cycle time while maintaining machining accuracy of a rigid tap. The numerical controller includes: a rigid tap control unit that executes a rigid tap by synchronizing rotational speed of a spindle with feedrate; a synchronization error monitoring unit that starts or terminates monitoring of a synchronization error between the rotational speed of the spindle and the feedrate at a point R set to a height equal to or higher than a top of a workpiece; and a workpiece top detection unit that detects a position of the workpiece top. The synchronization error monitoring unit starts monitoring the synchronization error at the position of the workpiece top instead of the point R.

Claims

1. A numerical controller that executes a rigid tap by starting synchronization between the rotational speed of a spindle and the feed rate of a rigid tap without stopping the spindle at a point R of which the height is set higher than a top of a workpiece, comprising:

a workpiece top detection unit that detects a position of the workpiece top; and

a synchronization error monitoring unit that starts monitoring for determining whether or not an error amount of a synchronization error in the synchronization exceeds a predetermined threshold value at the position of the workpiece top.

2. A numerical controller that executes a rigid tap, the numerical controller comprising:

a processor configured to;

detect a position of a workpiece top; and

determine, by machine learning, a point R which is a height higher than the workpiece top to start a synchronization between a rotational speed of a spindle and a feed rate of the rigid tap, the point R is determined to optimize at least one of a cycle time of the rigid tap and the or a synchronization error of the synchronization between the rotational speed of the spindle and the feed rate of the rigid tape.