Computer numerically controlled machines

A CNC machine comprising:

• a tool;
• a programmable control unit programmed to generate motion command signals which determine a programmed path for the tool;
• said programmable control unit also being programmed to generate programmed feedrate signals which, in an automatic mode of operation, determine a magnitude of a vectorial velocity for the tool in an instantaneous direction of said programmed path at each position on said programmed path as the tool moves automatically along said programmed path;
• a trajectory interpolator for processing said motion command signals and said programmed feedrate signals to produce interpolated position command signals;
• a position controller for moving said tool along said programmed path in accordance with said interpolated position command signals;
• and
• a manual pulse generator for manually generating a train of pulse signals of a variable frequency which is input to the trajectory interpolator;
• wherein said manual pulse generator includes a manually movable part movable in a forward direction and in a reverse direction and the frequency of the manually generated train of pulse signals is variable in proportion to the speed of movement of the manually movable part;
• wherein the trajectory interpolator processes said programmed feedrate signals and said train of manually generated pulse signals;
• wherein movement of the manually movable part in the forward direction causes the tool to move in a forward direction along the programmed path, the magnitude of the instantaneous vectorial velocity of the tool in the forward direction of the programmed path being controlled in proportion to the frequency of the train of manually generated pulse signals;
• wherein the manually movable part of the manual pulse generator comprises a handwheel which is rotatable in a forward direction and in a reverse direction, and the frequency of the manually generated train of pulse signals is variable in proportion to a speed of rotation of the handwheel;
• and
• wherein, in the automatic mode of operation, rotation of the handwheel in the reverse direction decreases the magnitude of the instantaneous vectorial velocity of the tool in the forward direction of the programmed path.

A CNC machine comprising:

• a tool;
• a programmable control unit programmed to generate motion command signals which determine a programmed path for the tool;
• said programmable control unit also being programmed to generate programmed feedrate signals which, in an automatic mode of operation, determine a magnitude of a vectorial velocity for the tool in an instantaneous direction of said programmed path at each position on said programmed path as the tool moves automatically along said programmed path;
• a trajectory interpolator for processing said motion command signals and said programmed feedrate signals to produce interpolated position command signals;
• a position controller for moving said tool along said programmed path in accordance with said interpolated position command signals;
• and
• a manual pulse generator for manually generating a train of pulse signals of a variable frequency which is input to the trajectory interpolator;
• wherein said manual pulse generator includes a manually movable part movable in a forward direction and in a reverse direction and the frequency of the manually generated train of pulse signals is variable in proportion to the speed of movement of the manually movable part;
• wherein the trajectory interpolator processes said programmed feedrate signals and said train of manually generated pulse signals;
• wherein movement of the manually movable part in the forward direction causes the tool to move in a forward direction along the programmed path, the magnitude of the instantaneous vectorial velocity of the tool in the forward direction of the programmed path being controlled in proportion to the frequency of the train of manually generated pulse signals;
• wherein the manually movable part of the manual pulse generator comprises a handwheel which is rotatable in a forward direction and in a reverse direction, and the frequency of the manually generated train of pulse signals is variable in proportion to a speed of rotation of the handwheel;
• and
• wherein, in the automatic mode of operation, rotation of the handwheel above a certain speed in the reverse direction causes the tool to move in a reverse direction of the programmed path.

A CNC machine comprising:

• a tool;
• a programmable control unit programmed to generate motion command signals which determine a programmed path for the tool;
• said programmable control unit also being programmed to generate programmed feedrate signals which, in an automatic mode of operation, determine a magnitude of a vectorial velocity for the tool in an instantaneous direction of said programmed path at each position on said programmed path as the tool moves automatically along said programmed path;
• a trajectory interpolator for processing said motion command signals and said programmed feedrate signals to produce interpolated position command signals;
• a position controller for moving said tool along said programmed path in accordance with said interpolated position command signals;
• and
• a manual pulse generator for manually generating a train of pulse signals of a variable frequency which is input to the trajectory interpolator;
• wherein the trajectory interpolator includes a velocity interpolator for processing said programmed feedrate signals and said train of manually generated pulse signals in such a manner that the magnitude of the vectorial velocity of the tool in the instantaneous direction of the programmed path is controllable proportionally in response to the frequency of the train of the manually generated pulse signals;
• and
• wherein said velocity interpolator is arranged to receive and process said programmed feedrate signals and the manually generated train of pulse signals to produce velocity magnitude and velocity direction signals, and said trajectory interpolator includes path interpolation means for receiving and processing said motion command signals and said velocity magnitude and velocity direction signals to produce said interpolated position command signals.