Apparatus and method for controlling the machining of workpieces using piezoceramic transducers

• US 8,080,918 B2
• Filed: 02/02/2007
• Issued: 12/20/2011
• Est. Priority Date: 02/03/2006
• Status: Active Grant

• Current Assignee: Ceramtec GmbH (Albemarle Corporation)
• Original Assignee: Ceramtec GmbH (Albemarle Corporation)
• Inventors: Tzschentke, Konrad, Schreiner, Hans-Jürgen, Handschuh, Kurt, Ben Amor, Raouf, Fripan, Michael
• Primary Examiner(s): Budd, Mark
• Application Number:
  US12/161,421
• Publication Number:
  US 20090165621A1
• Time in Patent Office: 1,782 Days
• Field of Search: 310/328, 310/338, 310/339
• US Class Current: 310/328
• CPC Class Codes: B23Q 1/34 Relative movement obtained by use of deformable elements, e.g. piezoelectric, magnetostrictive, elastic or thermally-dilatable elements sensitive elements capable of producing movement or displacement for purposes not limited to measurement G12B1/00
• CPC Class Codes: B23Q 17/0976 Detection or control of chatter B23Q15/12 takes precedence
• CPC Class Codes: Y10T 83/541 Actuation of tool controlled in response to work-sensing means
• CPC Class Codes: Y10T 83/85 Signal; e.g., alarm

Abstract

Patterns detection to input data containing a plurality of transactions, each transaction having at least one item, is carried out in the following way. Filter conditions for interesting patterns are received, and a first wet of filter conditions applicable in connection with generation of candidate patterns is determined.

Claims

1. A material-removing cutting tool, comprising a carrier which carries at least one cutting element, the cutting tool being mounted in a tool holder or bearing of a machine tool and the machine tool being equipped with a device for controlling the machining of workpieces, wherein piezoceramic transducers are provided as sensors and optionally additionally as voltage generators and these transducers are arranged at least one location on the cutting tool or on its bearing arrangement in order to be impinged upon by at least one component of the cutting force which arises during the machining and acts on the cutting tool, wherein the transducers are connected to the control device of the machine tool and in that the signals generated in the sensors as a result of the action of forces and evaluated by the control device can be used for controlling at least one of the rotational speed of the drive of the workpiece or of the cutting tool, the feed rate or the feed engagement.

2. A material-removing cutting tool according to claim 1, wherein the piezoceramic transducers are arranged between the cutting element and the carrier of the cutting tool.

3. A material-removing cutting tool according to claim 1, wherein the piezoceramic transducers are arranged between the carrier of the cutting tool and the tool holder, or between the shaft of the cutting element and the bearing in the machine tool.

4. A material-removing cutting tool according to claim 2, wherein the piezoceramic transducers are arranged both between the cutting element and the carrier of the cutting tool and between the carrier of the cutting tool and the tool holder, or between the shaft of the cutting element and the bearing in the machine tool.

5. A material-removing cutting tool according to claim 1, wherein the sensors and the voltage generators are arranged one above the other between the cutting element and the carrier of the cutting tool, between the carrier of the cutting tool or the tool holder, or between the shaft of the cutting element and the bearing in the machine tool, optionally separated from one another by an insulating support plate.

6. A material-removing cutting tool according to claim 1, wherein the voltage generators are connected to the voltage supply via a rectifier unit with electronic circuits.

7. A method for controlling the machining of workpieces on machine tools with cutting tools which carry at least one cutting element on a carrier and are mounted in a tool holder or bearing of a machine tool, wherein the machining is controlled with a control device, wherein piezoceramic transducers are arranged as sensors and optionally additionally as voltage generators at least one location on the cutting tool or on its bearing arrangement, at which location at least one component of the cutting force arising during the machining acts on the cutting tool, and wherein at least one of the force components of the cutting force acts on the transducers, wherein the signals generated by the action of forces on the transducers are compared to predefined limit values, in that upon overshooting or undershooting of a limit value a signal is transmitted to the control device of the machine tool and wherein the control device changes at least one of the rotational speed of the workpiece, the cutting tool, the feed rate or the feed engagement in order to eliminate the deviation which has occurred.

8. A method according to claim 7, wherein at least one of the components of the cutting force acting on the cutting tool is determined, and in that a signal for changing the cutting elements is generated if a predefined limit value of the cutting force is exceeded.

9. A method according to claim 7, wherein at least one of the components of the cutting force acting on the cutting tool is determined with the sensors, in that the degree of loading of the cutting element and/or of the machine tool is inferred from the magnitude of the signal and in that the machine tool is switched off if a predefined limit value is exceeded.

10. A method according to claim 7, wherein the voltage generated with the voltage generators is used for supplying electronic circuits.

11. A method according to claim 7, wherein, in the case of rotating cutting tools, communication between the piezoceramic sensors on the cutting tool and the control device on the machine tool is effected by means of radio signals, the signals of the transducers being transmitted to a transmitting and receiving device on the cutting tool and from there to a receiver on the machine tool.

12. A material-removing cutting tool, consisting of a carrier which carries at least one cutting element, wherein the cutting tool is mounted in a tool holder or bearing of a machine tool, and the machine tool is equipped with a device for controlling the machining of workpieces, wherein a plurality of piezoceramic, transducers are provided as sensors, and these transducers are arranged at least one location on the cutting tool or on its bearing arrangement in order to be impinged upon by at least one of components −

Fa, Ff or −

Fr of the cutting force (−

F) which arises during the machining and acts on the cutting tool, and the transducers are connected to the control device of the machine tool, characterized in that a plurality or piezoceramic transducers are provided as voltage generators for the voltage-supply of electronic circuits, and the piezoceramic transducers are arranged both between the cutting element and the carrier and between the carrier of the cutting tool and the tool holder and are supported in respective openings, and the sensors and the voltage generators are arranged one above the other, optionally separated from one another by an insulating support plate.

13. A material-removing cutting tool according to claim 12, wherein the voltage generators are connected to the electronic circuits for the voltage-supply via a rectifier unit.