Procedure for the numerical control of a workpiece on a grinding machine

• US 5,335,454 A
• Filed: 10/19/1992
• Issued: 08/09/1994
• Est. Priority Date: 10/17/1991
• Status: Expired due to Term

• Current Assignee: L Kellenberger & Co. AG
• Original Assignee: L Kellenberger & Co. AG
• Inventors: Ilek, Anton, Eugster, Emil, Thurnherr, Hugo
• Primary Examiner(s): LAVINDER, JACK W
• Application Number:
  US07/961,818
• Time in Patent Office: 659 Days
• Field of Search: 51/165.71, 51/165.74, 51/165.75, 51/165.87, 51/165.88
• US Class Current: 451/9
• CPC Class Codes: B24B 47/22 Equipment for exact control of the position of the grinding tool or work at the start of the grinding operation
• CPC Class Codes: G05B 19/4015 going to a reference at the beginning of machine cycle, e.g. for calibration

Abstract

A procedure for the numerically controlled processing of a workpiece on a grinding machine having a workholder for the workpiece as well as a wheelhead equipped with a grinding wheel, the wheelhead being pivoted on a wheelslide and able to be shifted together with the wheelslide in relation to the workholder, including detecting positions of a set of points situated within a working range of the grinding machine, covering coordinates of the set of points into basic data for a processing program of the grinding machine, and taking the basic data of the coordinates of the set of points into account while the workpiece is processed. A gauge is attached to the wheelhead and to a measuring device at a zero (M) of the machine, a spherical measuring head of the gauge presents a measuring point (IV) for detecting an initial position of the spherical measuring head in a coordinate system (X,Z) of the machine and coordinates of an existing position of the spherical measuring head are detected with the aid of the measuring device. A control unit enables an end position of the spherical measuring head to be detected where the measuring point (V) of the spherical measuring head would be if the wheelhead, which can be swivelled around a swivel axis (F), is swivelled through a specified angle, and the measuring point (V) passes through a patch (B). A check is performed to verify whether there is an discrepancy between an actual position of the spherical measuring head and the end position of the spherical measuring head.

Claims

1. A procedure for the numerically controlled processing of a workpiece on a grinding machine having a workholder for the workpiece as well as a wheelhead equipped with a grinding wheel, the wheelhead being pivoted on a wheelslide and able to be shifted together with the wheelslide in relation to the workholder, comprising

detecting positions of a set of points situated within a working range of the grinding machine,

converting coordinates of the set of points into basic data for a processing program of the grinding machine, and

taking the basic data of the coordinates of the set of points into account while the workpiece is processed,

wherein a first gauge is attached to the wheelhead, or optionally attached to a housing of the wheelhead, and to a measuring device in at a zero (M) of the machine,

wherein a spherical measuring head of the first gauge presents a measuring point (V) for detecting an initial position of the spherical measuring head in a coordinate system (X,Z) of the machine,

wherein coordinates of an existing position of the spherical measuring head, are detected with the aid of the measuring device,

wherein subsequently a control unit, being a component part of the grinding machine, enables an end position of the spherical measuring head to be detected where the measuring point (V) of the spherical measuring head would be if the wheelhead, which can be swivelled around a swivel axis (F), is swivelled through a specified angle, whereby the measuring point (V) passes through a displacement path (B) and,

wherein a check is performed to verify whether there is any discrepancy between an actual position of the spherical measuring head and the end position of the spherical measuring head.

2. Procedure as claimed in claim 1 wherein the wheelhead is swivelled back from the actual position into the initial position if there is any discrepancy between the actual position of the spherical measuring head and the end position of the spherical measuring head, wherein a shaft of the wheelhead is shifted within the coordinate system (X,Z) of the machine so that the swivel axis (F) of the wheelhead is brought into a different position (F'"'"'), wherein it is possible to calculate an expected swivel position of the spherical measuring head when the spherical measuring head is swung through a specified angle, wherein the wheelhead is swivelled through the specified angle and wherein a check is performed to verify whether there is any discrepancy between the actual position of the spherical measuring head and the expected swivel position of the spherical measuring head.

3. Procedure as claimed in claim 2 wherein coordinates of the swivel axis (F) of the wheelhead are stored in a memory as soon as there is no longer any discrepancy between the actual position of the measuring point (V) on the spherical measuring head and the expected swivel position of the spherical measuring head.

4. Procedure as claimed in claim 1 wherein coordinates of the swivel axis (F) of the wheelhead are stored in a memory as soon as there is no longer any discrepancy between the actual position of the spherical measuring head and the end position of the spherical measuring head.

5. Procedure as claimed in claim 4 wherein coordinates of points on the displacement path (B) of the measuring point (V) are measured, optionally by means of the measuring device attached to the workholder, and wherein a radium (R) of an arc defined by the displacement path (B) is detected from the coordinates of the points on the displacement path (B) as well as from the coordinates of the swivel axis (F) of the wheelhead.

6. Procedure as claimed in claim 4 wherein a position of a swivel shaft and a position of the swivel axis (F) of the wheelhead are simultaneously altered by a swivel movement of the grinding wheel around the swivel axis (F) of the wheelhead in such a manner that the grinding wheel is swivelled around at least one edge of the grinding wheel without altering coordinates (X,Z) of the at least one edge of the grinding wheel.

7. Procedure as claimed in claim 1 wherein a second gauge is assigned to a shaft on the wheelhead that bears the grinding wheel, wherein a distance between a measuring point of the second gauge and a clamping point (N) of the grinding wheel on the shaft is known, wherein the measuring device arranged the zero M of the machine is approached by the second gauge and wherein the coordinates of the tool clamping point (N) are memorized in the control unit.

8. Procedure as claimed in claim 1 wherein a measuring cube is attached to the workholder, wherein the measuring cube is approached by the first gauge on the wheelhead and wherein coordinates of the measuring cube are memorized.

9. Procedure as claimed in claim 4 wherein the measuring cube is approached in order to detect the position of an edge of the grinding wheel.

10. Procedure as claimed in claim 9 wherein the position of a dressing diamond is detected by approaching the dressing diamond with a tool.

11. Procedure as claimed in claim 9 wherein a position of a zero (A) of the workpiece is detected by approaching a shoulder of the workpiece with an edge of the grinding wheel and wherein the the position of the zero (A) of the workpiece is memorized.

12. Procedure as claimed in claim 9 wherein coordinates (X,Z) of at least one edge of the grinding wheel are detected after the wheelhead has performed a rotating movement around the swivel axis (F) of the wheelhead through a specified angle beta and wherein a new position of the at least one edge of the grinding wheel after swivelling is expressed in terms of coordinates (X,Z).

13. Procedure as claimed in claim 12 wherein a position of a swivel shaft and a position of the swivel axis (F) of the wheelhead are simultaneously altered by a swivel movement of the grinding wheel around the swivel axis (F) in such a manner that the grinding wheel is swivelled around at least one edge of the grinding wheel without altering coordinates (X, Z) of the at least one edge of the grinding wheel.