Method for controlling a device system having power tool and a motor-driven advancing mechanism

Patent metadata

Field	Value
Publication number	US-9798313-B2
Application number	US-201414767505-A
Country	US
Kind code	B2
Filing date	Feb 11, 2014
Priority date	Feb 14, 2013
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

A method for controlling a device system ( 10 ) having a saw blade ( 14 ) that is attached to a saw arm ( 15 ) and that can be moved along an advancing direction ( 26 ) by a motor-driven advancing mechanism ( 13 ), whereby there is an infeed motion of the saw arm ( 15 ) with the saw blade ( 14 ) into the workpiece ( 18 ) and, during the infeed motion of the saw arm ( 15 ) into the workpiece ( 18 ), a control unit ( 27 ) calculates an arc length (φ) of the saw blade ( 14 ) that is engaged with the workpiece ( 18 ), and the calculated arc length (φ) is compared to a pre-set, critical arc length (φ crit ) of the saw blade ( 14 ).

First claim

What is claimed is:

1. A method for controlling a device system having a saw blade attached to a saw arm, the saw blade movable along an advancing direction by a motor-driven advancer, the method comprising:
calculating, via a controller during an infeed motion of the saw arm with the saw blade into the workpiece, an arc length of the saw blade engaged with the workpiece; and
comparing the calculated arc length to a pre-set, critical arc length of the saw blade.

2. The method as recited in claim 1 wherein the infeed motion of the saw arm is interrupted and the saw blade undergoes an advancing movement in a forward direction along the advancing direction when the calculated arc length matches the critical arc length of the saw blade.

3. The method as recited in claim 2 wherein the controller calculates a movement of the saw blade in the forward direction during the advancing movement of the saw blade, and the calculated movement is compared to a pre-set, first movement.

4. The method as recited in claim 3 wherein the advancing movement of the saw blade is interrupted and further comprising providing an additional infeed motion of the saw arm into the workpiece when the calculated movement of the saw blade matches the first movement.

5. The method as recited in claim 4 wherein, during the further infeed motion of the saw arm, the controller calculates a further arc length of the saw blade engaged with the workpiece, and the further calculated arc length of the saw blade is compared to a further critical arc length.

6. The method as recited in claim 5 wherein the additional infeed motion of the saw arm is interrupted and further comprising providing a further advancing movement of the saw blade along the advancing direction in a backward direction opposite from the forward direction when the further calculated arc length matches the further critical arc length of the saw blade.

7. The method as recited in claim 6 wherein, during the further advancing movement of the saw blade, the control unit calculates a further movement of the saw blade in the backward direction, and the calculated further movement is compared to a pre-set, second movement.

8. The method as recited in claim 7 wherein the further advancing movement of the saw blade is interrupted when the further calculated movement of the saw blade matches the second movement.

Assignees

• Hilti Ag

Inventors

• Brugger Peter
• Studer Georg

Classifications

• B28D7/005

  Devices for the automatic drive or the program control of the machines · CPC title

• B28D1/045

  Sawing grooves in walls; sawing stones from rocks; sawing machines movable on the stones to be cut · CPC title

• B23D59/002 Primary

  for the position of the saw blade (mounting for swiveling or tilting a circular saw blade B27B5/36; portable power-driven circular saws with adjustment for cutting depth or amount of tilting B27B9/02) · CPC title

• G05B2219/45144

  Saw · CPC title

• G05B19/402 Primary

  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 title