Numerical control system using position number generator

Claim 2

In a numerical control system for controlling the displacement of an element along at least one axis: means for generating digital position quantities in a sequence which represents the desired displacement of the element; means for comparing the digital position quantities to a periodically varying reference quantity and for generating a signal whenever a predetermined relationship exists between the position and reference quantities; and displacement control means receiving the signals and responsive to the time spacings therebetween to control displacement of the element.

Claim 3

Apparatus as defined in claim 1 wherein the means for generating digital position quantities includes a digital computer.

Claim 4

Apparatus as defined in claim 2 including a tape reader connected in input relation to the computer for reading program data into the computer.

Claim 5

Apparatus as defined in claim 1 including clock means controlling said means for generating such that the digital position quantities occur at least substantially periodically.

Claim 6

Apparatus as defined in claim 4 wherein the position quantities are whole numbers within a predetermined numerical range, the means for comparing including a register for receiving said whole numbers in sequence.

Claim 7

Apparatus as defined in claim 5 including means for clearing the register between the occurrence of position numbers in the sequence.

Claim 8

In a numerical control system for controlling the displacement of an element along at least one axis: means for generating a sequence of digital position quantities representing the desired displacement of the element; means for cyclically and periodically generating digital reference quantities traversing a fixed scale; means for comparing the digital displacement quantities to the digital reference quantities and generating a sequence of signals wherein each signal occurs whenever a predetermined relationship exists between the quantities; and displacement control means responsive to the phase relationship between the signals in said sequence of signals to cause displacement of the element.

Claim 9

In a numerical control system for controlling the displacement of an element along at least one axis: means for generating a sequence of digital position quantities representing the desired displacement of the element; means for cyclically and periodically generating digital reference quantities traversing a fixed scale; means for comparing the digital displacement quantities to the digital reference quantities and generating a sequence of signals wherein each signal occurs whenever a predetermined relationship exists between the quantities; and displacement control means responsive to the phase relationship between the signals in said sequence of signals to cause displacement of the element.

Claim 10

Apparatus as defined in claim 7 wherein the means for generating digital position quantities includes a digital computer.

Claim 11

Apparatus as defined in claim 8 including a tape reader connected in input relation to the computer for reading program data into the computer.

Claim 12

Apparatus as defined in claim 7 including clock means commonly controlling the respective means for generating the position and reference quantities.

Claim 13

Apparatus as defined in claim 7 wherein said position and reference quantities are multibit digital numbers within a predetermined numerical range said means for comparing comprises a register for receiving said sequence of position quantities, and a comparator for simultaneously comparing bits of the reference quantities to correspondingly ordered bits of the position quantities.

Claim 14

Apparatus as defined in claim 7 wherein the displacement control means includes a phase-analog servo loop.

Claim 17

The method of claim 13 wherein the step of generating includes the substep of reading displacement characters from a stored program into a digital computer.

Claim 18

The method of claim 13 wherein at least two consecutive digital position numbers are equal whereby the time spacings between at least three consecutive pulses in the pulse train are equal.

Claim 19

The method of claim 13 wherein the digital position numbers increase cyclically within said range by a given numerical increment whereby the time spacings between pulses in the pulse train increase.

Claim 20

The method of claim 13 wherein the digital position numbers decrease cyclically within said range by a given numerical increment whereby the time spacings between pulses in the train decrease.