Device, particularly protective sensor system, for a machine tool

• US 8,670,844 B2
• Filed: 11/11/2008
• Issued: 03/11/2014
• Est. Priority Date: 01/11/2008
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Krapf, Reiner, Braun, Heiko, Hees, Alexander Werner, Mahler, Michael
• Primary Examiner(s): Ali, Mohammad
• Assistant Examiner(s): Booker, Kelvin
• Application Number:
  US12/811,960
• Publication Number:
  US 20110022188A1
• Time in Patent Office: 1,946 Days
• Field of Search: 700/12, 700/13, 700/29, 700/30, 700/31, 192/129.R
• US Class Current: 700/12
• CPC Class Codes: F16P 3/00 Safety devices acting in conjunction with the control or operation of a machine; Control arrangements requiring the simultaneous use of two or more parts of the body F16P5/00 takes precedence
• CPC Class Codes: F16P 3/147 using electro-magnetic technology, e.g. tags or radar
• CPC Class Codes: G05B 19/05 Programmable logic controllers, e.g. simulating logic interconnections of signals according to ladder diagrams or function charts
• CPC Class Codes: G05B 19/406 characterised by monitoring or safety G05B19/19 takes precedence
• CPC Class Codes: G05B 2219/50177 Protection for operator during operation, machining
• CPC Class Codes: Y10T 83/173 Arithmetically determined program
• CPC Class Codes: Y10T 83/175 With condition sensor

Abstract

The invention relates to a device, particularly a machine tool device, having at least one computer (10), at least one transmitter (12) for transmitting a transmission signal (S1, S2), at least one receiver (14) for receiving at least one receiving signal (E1, E2, E3, E4) excited by the transmission signal (S1, S2), and at least one analysis unit (16) which is provided to calculate at least one parameter (P1, P2, P3, P4) by means of the receiving signal (E1, E2, E3, E4). The invention provides that the computer unit (10) is provided to compare the parameter (P1, P2, P3, P4) to at least one comparison parameter (V1, V2, V3, V4) calculated by means of at least one model (M).

Claims

1. A machine tool device, having at least one computer, at least one transmitter for transmitting a transmission signal, at least one receiver for receiving at least one receiving signal excited by the transmission signal, and at least one analysis unit which is provided to calculate at least one parameter by means of the receiving signal wherein the computer unit is provided to compare the parameter to at least one comparison parameter calculated by means of at least one model, wherein the machine tool is used to work on a work piece, and wherein comparing the parameter to the at least one comparison parameter can be used to determine the thickness of a layer of the work piece and to detect the presence of an object other than the work piece.

2. The machine tool device according to claim 1 wherein the parameter is a reflection variable or a transmission variable.

3. The machine tool device according to claim 1, wherein the comparison parameter is assigned to at least one characteristic vector of the model.

4. The machine tool device according to claim 3 wherein the characteristic vector provides at least a thickness of a layer whose interaction is described with the transmission signal with the aid of the model.

5. The machine tool device according to claim 3, wherein the characteristic vector comprises at least one di-electricity constant of a layer whose interaction is described by the transmission signal with the aid of the model.

6. The machine tool device according to claim 3, wherein the characteristic vector provides at least a number of layers which indicates the number of layers of an object that is examined with the aid of the transmission signal, which is incorporated in the calculation by means of the model.

7. The machine tool device according to claim 1, wherein the computer provides software, which is provided to calculate the comparison parameter by means of the model.

8. The machine tool device according to claim 7 wherein an input unit for putting in at least one characteristic variable, which is used by the software as input value for calculating the comparison parameter.

9. The machine tool device according to claim 7, wherein the software is provided to determine a value of the comparison parameter, which realizes a minimal deviation of the comparison parameter from the parameter.

10. The machine tool device according to claim 7, wherein the software is provided to distinguish at least two characteristic variable areas of a magnitude of error that has been calculated by means of the model.

11. The machine tool device according to claim 1, wherein the transmission signal is a high frequency signal.

12. Protective sensor system with a machine tool device according to claim 1.

13. Procedure for use with a machine tool device according to claim 1, wherein at least one transmission signal is transmitted, at least one receiving signal that has been excited by the transmission signal is received, one parameter is calculated at least by means of the receiving signal and the parameter is compared with at least one comparison parameter that has been calculated by means of a model.

14. The procedure of claim 13 further comprising the step of stopping a cutting element of a machine tool when comparing the parameter to the at least one comparison parameter indicates the presence of an object other than a work piece.

15. A safety device for detecting objects in a danger zone of a machine tool, the safety device comprising:

a computer;

a transmitter for transmitting a first signal into the danger zone;

a receiver for receiving a second signal from the danger zone excited by the first signal; and

an analysis unit,

wherein the machine tool is used to operate on a work piece, and wherein the analysis unit calculates at least one measurement parameter using the second signal, and wherein the computer compares the at least one measurement parameter to a comparison parameter to determine the presence of an object other than the work piece in the danger zone; and

wherein the comparison parameter relates to the thickness of a layer of the work piece and is calculated by means of a model.

16. The safety device of claim 15 wherein the at least one measurement parameter can be used to measure variations in the accumulation of layers.

17. The safety device of claim 16 wherein an increase in the accumulation of layers can indicate the presence of an object other than the work piece in the danger zone.

18. The safety device of claim 15 wherein the model uses Maxwell equations to calculate the accumulation of layers of the work piece.