Adjustment mechanism for rotation runout and dynamic balance of rotating tool

Patent metadata

Field	Value
Publication number	US-9511464-B2
Application number	US-201514598763-A
Country	US
Kind code	B2
Filing date	Jan 16, 2015
Priority date	Jan 20, 2014
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

A tool holder holding a rotating tool can be sucked in a direction of a rotational axis of a spindle and a direction perpendicular to the direction of the rotational axis, using a chuck. A projection is provided on an outer peripheral surface of the tool holder, and caused to collide against another projection with the spindle kept rotating, to displace the tool holder. Thus, runout and dynamic balance of the rotating tool are adjusted.

First claim

The invention claimed is:

1. An adjustment mechanism for rotation runout and dynamic balance of a rotating tool that is attached to a spindle and is held by a tool holder, the adjustment mechanism comprising:
a chuck which sucks the tool holder in a direction of a rotational axis of the spindle and which sucks the tool holder in a direction perpendicular to the direction of the rotational axis of the spindle;
a first projection provided on an outer peripheral surface of the tool holder;
a second projection provided on a plane formed by a trajectory of the first projection when the spindle is rotated; and
a distance change element that enables any change in a distance from the rotational axis of the spindle to the second projection until the first projection and the second projection collide against each other, wherein
the position of the tool holder is displaced if the first projection and the second projection collide with each other by an external force applied to the first projection,
a plurality of the first projections are disposed on the outer peripheral surface of the tool holder so as to have different phases in a rotation direction,
a plurality of rotation planes formed by the trajectories of the first projections is arranged so as not to overlap one another with the spindle kept rotating, and
changing a relative position between the spindle and the second projection enables a position to be set where any one of the first projections and the second projection collide against each other.

2. The adjustment mechanism for rotation runout and dynamic balance of the rotating tool according to claim 1 , wherein a number of the first projection is four, and the first projections have phases different from one another by 90° in the rotation direction.

3. The adjustment mechanism for rotation runout and dynamic balance of the rotating tool according to claim 1 , wherein the spindle and the dynamic balance adjustment mechanism are mounted in a machine tool to allow any change in a relative distance between the first projection and the second projection using a translation axis or a rotational axis of the machine tool.

4. The adjustment mechanism for rotation runout and dynamic balance of the rotating tool according to claim 3 , wherein
the machine tool is controlled by a numerical controller, and
the numerical controller comprises an adjustment section which calculates a magnitude of dynamic balance of the rotating tool from a magnitude of position deviation of the translation axis or the rotational axis, calculates a direction in which the dynamic balance deviates, from the rotation angle of the spindle and a phase difference in the position deviation, and automatically controls the respective axes to adjust a position of the tool holder so as to minimize the magnitude of the dynamic balance.

5. The adjustment mechanism for rotation runout and dynamic balance of the rotating tool according to claim 3 , wherein
the machine tool is controlled by a numerical controller and comprises a sensor that measures an amount and a phase of rotation runout of the rotating tool, and
the numerical controller comprises an adjustment section which calculates a direction in which the dynamic balance deviates, from the rotation angle of the spindle and the phase of the rotation runout, and automatically controls the respective axes to adjust a position of the tool holder so as to minimize an amount of the rotation runout.

6. The adjustment mechanism for rotation runout and dynamic balance of the rotating tool according to claim 1 , wherein
the chuck is a vacuum chuck, and
the adjustment mechanism further comprises a degree-of-vacuum change unit that enables a degree of vacuum of the vacuum chuck to be optionally changed, and reduces the degree of vacuum when the rotation runout or dynamic balance of the rotating tool is adjusted.

7. The adjustment mechanism for rotation runout and dynamic balance of the rotating tool according to claim 1 , wherein
the chuck is a magnetic chuck that generates a magnetic force using a permanent magnet, and
the adjustment mechanism further comprises a mechanism that feeds an air pressure to an attachment surface of the tool holder and a mechanism that enables the air pressure to be optionally changed, and increases the air pressure when the rotation runout or dynamic balance of the rotating tool is adjusted.

8. The adjustment mechanism for rotation runout and dynamic balance of the rotating tool according to claim 4 , wherein the numerical controller is connected to a collision detection unit that detects a collision between the first projection and the second projection based on the position deviation.

Assignees

• Fanuc Corp

Inventors

• Ebihara Kenzo

Classifications

• B23Q17/2216 Primary

  for adjusting the tool into its holder (B23Q17/0923 - B23Q17/0942 takes precedence) · CPC title

• B23Q2017/001

  Measurement or correction of run-out or eccentricity · CPC title

• B23Q11/0035 Primary

  by adding or adjusting a mass, e.g. counterweights · CPC title

• Y10T279/11

  Vacuum · CPC title

• B23Q15/22

  Control or regulation of position of tool or workpiece · CPC title