Drive controller for machine tool

• US 6,618,641 B2
• Filed: 08/17/2001
• Issued: 09/09/2003
• Est. Priority Date: 12/17/1999
• Status: Expired due to Term

• Current Assignee: Star Micronics Company Limited
• Original Assignee: Star Micronics Company Limited
• Inventors: Kurihara, Shigeyuki, Endo, Nobuyuki
• Primary Examiner(s): Paladini, Albert W.
• Assistant Examiner(s): CABRERA, ZOILA E
• Application Number:
  US09/913,647
• Publication Number:
  US 20020158597A1
• Time in Patent Office: 753 Days
• Field of Search: 700/159, 700/183-184, 700/187-190, 700/193, 318/560, 318/568.1
• US Class Current: 700/159
• CPC Class Codes: G05B 19/21 using an incremental digital measuring device
• CPC Class Codes: G05B 19/4142 characterised by the use of a microprocessor G05B19/4141 takes precedence
• CPC Class Codes: G05B 2219/35373 Data storage, buffer
• CPC Class Codes: G05B 2219/42211 Command position by time value, proportional to total displacement
• CPC Class Codes: G05B 2219/43174 Simulating cam motion mechanism
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

Each time the number of cumulative rotations of a spindle rotating motor 11 reaches the number of cumulative rotations set in a position data table T, a CPU 22 reads out the mobile positions of a work piece and tool at thus reached number of cumulative rotations and the next number of cumulative rotations to reach from a position data storage section 25, and reads out a moving speed characteristic between the reached number of cumulative rotations and the next number of cumulative rotations to reach from a moving speed characteristic storage section 27 according to an auxiliary operation designation in the position data table T. Thereafter, assuming the reached number of cumulative rotations to be a start point and the next number of cumulative is rotations to reach to be an end point, the CPU 22 divides the part between the start and end points into predetermined timings, and defines the mobile positions of the workpiece and tool at each of the divided timings according to the read-out mobile positions of the workpiece and tool and moving speed characteristic.

Claims

1. A drive control apparatus for a machine tool for machining a workpiece into a desirable form by rotating said workpiece about a predetermined axis and moving at least one of said workpiece and a tool for machining said workpiece;

said apparatus comprising;

reference timing signal generating means for generating a reference timing signal at each predetermined rotational angle in said predetermined axis;

reference timing signal count means for counting the number of occurrences of said reference timing signal;

position data storage means for storing position data respectively set so as to correspond to a plurality of different count values of said number of occurrences, said position data indicating a mobile position of at least one of said workpiece and tool;

moving speed characteristic storage means for storing a moving speed characteristic of at least one of said workpiece and tool between two points in said position data; and

mobile position defining means for reading out, each time the number of occurrences of said reference timing signal counted by said reference timing signal count means reaches said count value, position data corresponding to said reached count data and a next count data to reach from said position data storage means, and a moving speed characteristic corresponding to a part between said reached count value and said next count value to reach from said moving speed characteristic storage means, dividing said part between said reached count value and said next count value to reach into predetermined timings, and defining a mobile position of at least one of said workpiece and tool at each of said divided timings according to said read-out position data and moving speed characteristic;

wherein at least one of said workpiece and tool is moved according to said mobile position defined by said mobile position defining means.

2. A drive control apparatus for a machine tool according to claim 1, wherein said machine tool comprises a drive motor section for moving said at least one of said workpiece and tool;

and

wherein said mobile position defining means sequentially outputs said defined mobile position as command data to said drive motor section in response to rotation of said predetermined axis.

3. A drive control apparatus for a machine tool according to claim 1, wherein said the machine tool comprises a drive motor section for moving said at least one of said workpiece and tool;

and

wherein said mobile position defining means sequentially outputs said defined mobile position as command data to said drive motor section at said divided timings.

4. A drive control apparatus for a machine tool according to claim 1, wherein said count value is defined such that said position data set so as to correspond to said count value represents said mobile position at a position where a machining form is changed such as a point of inflexion, a corner part, and a curvature changing point in said desirable form.

5. A drive control apparatus for a machine tool according to claim 1, wherein said count value is defined so as to represent said mobile position at a dividing position where a curved part in said desirable form is divided.

6. A drive control apparatus for a machine tool according to claim 1, wherein said moving speed characteristic is set so as to decelerate said moving speed of at least one of said workpiece and tool near a trailing end of said moving speed characteristic.