Tool presetter and tool offset amount calculation method

• US 20020129681A1
• Filed: 01/15/2002
• Published: 09/19/2002
• Est. Priority Date: 01/31/2001
• Status: Active Grant

• Current Assignee: MORI Seiki Company Limited
• Original Assignee: MORI Seiki Company Limited
• Inventors: Ono, Katsuaki
• Granted Patent: US 6,640,676 B2
• Time in Patent Office: Days
• US Class Current: 82/1.11
• CPC Class Codes: G05B 19/404 characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia G05B19/19, G05B19/41 take precedence
• CPC Class Codes: G05B 2219/45125 Four axis, spindle lathe
• CPC Class Codes: G05B 2219/50026 Go to reference plane, cube
• CPC Class Codes: Y10T 408/08 with means to regulate operation by use of templet, tape, card, or other replaceable information supply
• CPC Class Codes: Y10T 409/308624 with limit means to aid in positioning of cutter bit or work [e.g., gauge, stop, etc.]
• CPC Class Codes: Y10T 82/10 Process of turning
• CPC Class Codes: Y10T 82/2502 with program control

Abstract

A tool presetter and a tool offset amount calculation method are provided which ensure easy and accurate determination of reference tool offset amounts in a machine tool having a pivotal tool spindle stock. The tool presetter is mounted in a composite lathe having a pivotal tool spindle stock 17. The tool presetter calculates tool offset amounts Oz (=A−Zm), Ox (=B−Xm) on the basis of machine coordinate values Zm, Xm of the tool spindle stock detected when a nose of a tool T is in contact with Z-axis and X-axis detection points of a presetter sensor 18 with the tool spindle stock 17 pivoted by a pivot angle α, and machine coordinate values A, B of the Z-axis and X-axis detection points of the presetter sensor 18, and calculates reference tool offset amounts Lz, Lx from predetermined expressions on the basis of the tool offset amounts Ox, Oz and the pivot angle α of the tool spindle stock 17.

Claims

1. A tool presetter to be mounted in a machine tool having a pivotal tool spindle stock, the tool presetter comprising:

a presetter sensor provided at a predetermined position; and

control means which determines machine coordinate values of the tool spindle stock when a nose of a tool attached to the tool spindle stock is in contact with the presetter sensor and, on the basis of the machine coordinate values and a pivot angle of the tool spindle stock detected when the tool nose is in contact with the presetter sensor, calculates a reference tool offset amount as measured along a control axis with the tool spindle stock being set to position a tool spindle parallel to the control axis.

2. A tool presetter as set forth in claim 1, further comprising display means for displaying the machine coordinate values of the tool spindle stock which are outputted from the control means.

3. A tool presetter as set forth in claim 1, wherein the control means comprises a storage section for storing the calculated reference tool offset amount.

4. A tool presetter as set forth in claim 1, wherein the control means calculates, as the reference tool offset amount, dimensions of the tool as measured along a Z-axis and an X-axis when the tool spindle stock is set to position the tool spindle parallel to the Z-axis.

5. A tool presetter as set forth in claim 1, wherein the control means calculates, as the reference tool offset amount, differences between dimensions of a reference tool and dimensions of an object tool as measured along a Z-axis and an X-axis when the tool spindle stock is set to position the tool spindle parallel to the Z-axis.

6. A tool offset amount calculation method for use in a machine tool having a pivotal tool spindle stock to which a tool is attached, the method comprising the steps of:

if it is impossible to bring a nose of the tool into contact with a presetter sensor provided at a predetermined position with the tool spindle stock being set to position a tool spindle parallel to a control axis, determining machine coordinate values of the tool spindle stock when the tool nose is in contact with the presetter sensor after the tool spindle stock is pivoted by a pivot angle from a position at which the tool spindle is parallel to the control axis to bring the tool nose into contact with the presetter sensor; and

calculating a reference tool offset amount as measured along the control axis with the tool spindle stock being set to position the tool spindle parallel to the control axis on the basis of the machine coordinate values and the pivot angle of the tool spindle stock.

7. A method as set forth in claim 6, wherein the reference tool offset amount to be calculated is dimensions of the tool as measured along a Z-axis and an X-axis when the tool spindle stock is set to position the tool spindle parallel to the Z-axis.

8. A method as set forth in claim 6, wherein the reference tool offset amount to be calculated is differences between dimensions of a reference tool and dimensions of an object tool as measured along a Z-axis and an X-axis when the tool spindle stock is set to position the tool spindle parallel to the Z-axis.