Lathe control system

Abstract

Lathe control systems and methods are described including stopping a motor prior to reversing direction as well as methods and systems that implement voltage and/or current protection thresholds.

1 . A lathe comprising:
 an electrical motor drivingly coupled to a shaft of the lathe; and   a controller that controls a power applied to the electrical motor during operation, wherein when an operating direction of the electrical motor is reversed from a first direction to a second direction, the controller powers off the electrical motor until the electrical motor stops rotating and then the controller applies power to the electrical motor to drive the electrical motor in the second direction.   
     
     
         2 . The lathe of  claim 1 , further comprising a forward and reverse rotation input detection circuit, wherein the forward and reverse rotation input detection circuit outputs a signal to the control indicating a desired operational direction of the electrical motor, and the controller controls the operating direction of the electrical motor based at least in part on the signal. 
     
     
         3 . The lathe of  claim 2 , wherein the forward and reverse rotation input detection circuit comprises a forward and reverse input connected with a first capacitor C 1  and a second resistor R 2  that are connected in series to the input to form a loop, and wherein a connecting terminal of the first capacitor C 1  and the second resistor R 2  is connected to a power supply through a first resistor R 1 , wherein the connecting terminal is an I/O terminal, and wherein the other terminal of the first capacitor C 1  is grounded. 
     
     
         4 . The lathe of  claim 1 , wherein the controller comprises a stepless speed-regulation module and a torque-regulation module. 
     
     
         5 . A method comprising:
 detecting a signal to reverse an operating direction of an electrical motor drivingly coupled to a shaft of the lathe from a first direction to a second direction;   powering off the electrical motor until the electrical motor stops rotating; and   applying power to the electrical motor to drive the electrical motor in the second direction.   
     
     
         6 . The method of  claim 5 , further comprising controlling the electrical motor with stepless speed-regulation and torque regulation. 
     
     
         7 - 13 . (canceled) 
     
     
         14 . A method comprising:
 detecting an electrical characteristic of at least one of an electrical bus and an electrical motor of a lathe; and   controlling at least one aspect of the electrical motor's operation based on a comparison of the detected electrical characteristic to a preset threshold.   
     
     
         15 . The lathe of  claim 14 , wherein the electrical characteristic is at least one of a bus voltage, a motor voltage, and a motor current. 
     
     
         16 . The lathe of  claim 15 , wherein the preset threshold is at least one of a bus over-voltage protection point, a bus under-voltage protection point, and a motor over voltage protection point. 
     
     
         17 . The lathe of  claim 14 , wherein the electrical characteristic is a motor current, and the preset threshold is at least one of a hardware protection point, a software protection point, and a and a locked-rotor protection point. 
     
     
         18 . The lathe of  claim 17 , wherein the preset threshold is the locked-rotor protection point, wherein controlling at least one aspect of the electrical motor's operation includes limiting the motor current to a lower second current threshold after the motor current is above the locked-rotor protection point for a predetermined duration. 
     
     
         19 . The lathe of  claim 14 , wherein controlling at least one aspect of the electrical motor's operation includes turning off power to the electrical motor based on the comparison of the detected electrical character to the preset threshold. 
     
     
         20 . The method of  claim 14 , further comprising controlling the electrical motor with stepless speed-regulation and torque regulation. 
     
     
         21 - 27 . (canceled)