Method and apparatus for digital contouring using stepping motors with close approximation of desired path

Claim 3

The invention as defined in claim 1 in which each axis receives the simulated increments and the actual increments and in which the step of inhibiting includes inhibiting only alternate received increments on each axis whereby every alternate increment received by an axis is an actual increment which effects movement of the tool along the actual path.

Claim 4

The invention as defined in claim 2 in which the step of inhibiting each odd numbered pulse received by an axis.

Claim 5

The invention as defined in claim 1 in which an actual increment of movement on one axis causes a known deviation of the element from the desired path and in which the step of determination for each step includes determining the total deviation produced by both simulated and actual movements.

Claim 6

The invention as defined in claim 4 in which the desired path is linear and in which the step of determining uses the same quantity of deviation for both simulated and actual steps on the same axis.

Claim 7

The invention as defined in claim 4 in which the desired path is arcuate and in which the step of determining includes the step of using the same deviation for sequentially occurring simulated and actual increments of movement of the same axis and for changing the deviation by a count of 1 for only each simulated movement.

Claim 8

The invention as defined in claim 1 in which the step of determination includes the steps of maintaining an algebraic count of the deviation between the actual path and the desired path, in which a change in sign of the deviation after an increment on one axis indicates a crossing of the desired path and in which the next increment is directed to the other axis irrespective of whether it is a simulated increment or an actual increment.

Claim 9

A numerically controlled contour system for producing movement of an element substantially along a desired path by sequential increments of movement on a first and a second axis perpendicular to each other comprising a first stepping motor means connected to the element for moving said element an increment of movement for each change of energization received by said motor means on the first axis, a second stepping motor means connected to the element for moving said element an increment of movement for each change of energization received by said second motor means on the second axis, means for receiving information of the desired path, means for producing simulated increments of movement and actual increments of movement, means for determining after each increment the deviation that would be produced by a determination path containing both increments of movement and directing the next increment to the axis which would effect a crossing of the desired path by the determination path and means connected to each stepping motor means for permitting only actual increments of movement on each axis to effect a change of energization to produce a movement of the element.

Claim 10

A numerically controlled contour system for producing movement of an element substantially along a desired path by sequential increments of movement on a first and a second axis perpendicular to each other comprising a first stepping motor means connected to the element for moving said element an increment of movement for each change of energization received by said motor means on the first axis, a second stepping motor means connected to the element for moving said element an increment of movement for each change of energization received by said second motor means on the second axis, means for receiving information of the desired path, means for producing simulated increments of movement and actual increments of movement, means for determining after each increment the deviation that would be produced by a determination path containing both increments of movement and directing the next increment to the axis which would effect a crossing of the desired path by the determination path and means connected to each stepping motor means for permitting only actual increments of movement on each axis to effect a change of energization to produce a movement of the element.

Claim 11

The invention as defined in claim 8 in which the permitting means for each axis includes a two-state means, in which the two-state means is connected to alter its state for every increment received by its axis and in which only the increments of movement that occur while the two-state means is in one of its states constitutes an actual movement.

Claim 12

The invention as defined in claim 8 in which an increment of movement of the element on an axis produces a known deViation of the actual path from the desired path, in which the determining means includes an error register for maintaining the algebraic sum of the deviations after each simulated and actual increment and in which the known quantity added to the error register is the same for either a simulated increment or an actual increment.

Claim 13

The invention as defined in claim 10 in which the desired path is linear and there are means for maintaining the known quantity to be added to the error register constant.

Claim 14

The invention as defined in claim 10 in which the desired path is arcuate, in which there are means for varying the known quantity after each increment of movement of the element and in which each simulated increment and each actual increment causes the known quantity to be added to the error register.