Spindle speed control monitor

Abstract

Abstract THE FEEDBACK WAVEFORM IN A CLOSED LOOP POSITION CONTROLLING SYSTEM FOR CONTROLLING THE SPEED OF A SPINDLE IS USED TO GENERATE AN ENVELOPE WAVEFORM WHICH SETS THE LIMITS OF THE SYSTEM RESPONSE. IN THE CLOSED LOOP POSITION CONTROLLING SYSTEM, THE SPEED OF THE SPINDLE MOTOR IS CONTROLLED BY A TRAIN OF VELOCITY PULSES. THE VELOCITY PULSES ARE ACCUMULATED BY A COMMAND PHASE COUNTER WHOSE OUTPUT PHASE IS COMPARED WITH THE PHASE OF A FEEDBACK WAVEFORM WHOSE PHASE IS RELATED TO THE SPINDLE MOTOR ROTATIONAL POSITIN. THE PHASE DIFFERENCE DRIVES THE MOTOR IN A DIRECTION TO REDUCE THE PHASE DIFFERENCE TO ZERO. AT THE START OF EACH SPINDLE SPEED MONITORING CYCLE, A FAST AND SLOW PHASE COUNTER ARE CLEARED, PRESET AND STARTED COUNTING BY ONE OF THE FEEDBACK PULSES. THE PRESETTING OPERATION CAUSES THE INITIAL PHASE PRESET OF THESE COUNTERS TO STRADDLE THE PHASE OF THE FEEDBACK PULSE. THE FAST COUNTER PROVIDES AN OUTPUT WAVEFORM WHICH HAS ITS PHASE ADVANCING SLIGHTLY FASTER THAN THE PHASE OF THE OUTPUT SIGNAL OF THE COMMAND PHASE COUNTER. THE SLOW COUNTER PROVIDES AN OUTPUT WAVEFORM WHICH HAS ITS PHASE ADVANCING SLIGHTLY SLOWER THAN THE PHASE OF THE OUTPUT SIGNAL OF THE COMMAND PHASE COUNTER. THE TERMINATION OF EACH FEEDBACK PULSE IS COMPARED IN PHASE WITH THE OUTPUTS FROM THE FAST AND SLOW COUNTERS, AND AN INDICATION IS PROVIDED IF THE FEEDBACK WAVEFORM FALLS OUTSIDE OF THE LIMITS SET BY THE FAST AND SLOW COUNTER WAVEFORMS.

Inventors

• 👤 Leroy U C Kelling

Bibliographic Details