Abstract: Approaches herein provide a plasma arc torch including a tip surrounding an electrode, the electrode having a proximal end and a distal end, and a shield surrounding the tip, the shield including an exit orifice proximate the distal end of the electrode. The torch may further include a linear actuating device coupled to the electrode for actuating the electrode such that the distal end of the electrode moves axially relative to the tip and the exit orifice of the shield. In some approaches, the linear actuating device is operable to actuate the electrode along a central longitudinal axis extending through the tip. In some approaches, the linear actuating device may include one of: a micro linear drive motor, a micro linear stepper motor, a voice coil, a solenoid coil, and a magnetostrictive actuator. In some approaches, the electrode is actuated during a welding or cutting cycle of the torch.

Abstract: An automated plasma cutting system is provided that includes a positioning system mounted to a support, an automated plasma arc torch mounted to the positioning system, and at least one power supply operatively connected to the automated plasma arc torch. The power supply may provide electrical power and fluid flow to the automated plasma arc torch for operation. The system further includes a controller in communication with the automated plasma arc torch and the power supply, and an auxiliary plasma arc torch operatively connected to the power supply, wherein the power supply provides electrical power and fluid flow to both the automated plasma arc torch and the auxiliary plasma arc torch. The automated plasma arc torch may process the workpiece to generate a set of features, while the auxiliary plasma arc torch may process/cut a residual framework of the workpiece remaining after formation of the set of features.

Abstract: Approaches herein provide a plasma arc torch including a tip surrounding an electrode, the electrode having a proximal end and a distal end, and a shield surrounding the tip, the shield including an exit orifice proximate the distal end of the electrode. The torch may further include a linear actuating device coupled to the electrode for actuating the electrode such that the distal end of the electrode moves axially relative to the tip and the exit orifice of the shield. In some approaches, the linear actuating device is operable to actuate the electrode along a central longitudinal axis extending through the tip. In some approaches, the linear actuating device may include one of: a micro linear drive motor, a micro linear stepper motor, a voice coil, a solenoid coil, and a magnetostrictive actuator. In some approaches, the electrode is actuated during a welding or cutting cycle of the torch.

Abstract: An automated plasma cutting system is provided that includes a positioning system mounted to a support, an automated plasma arc torch mounted to the positioning system, and at least one power supply operatively connected to the automated plasma arc torch. The power supply may provide electrical power and fluid flow to the automated plasma arc torch for operation. The system further includes a controller in communication with the automated plasma arc torch and the power supply, and an auxiliary plasma arc torch operatively connected to the power supply, wherein the power supply provides electrical power and fluid flow to both the automated plasma arc torch and the auxiliary plasma arc torch. The automated plasma arc torch may process the workpiece to generate a set of features, while the auxiliary plasma arc torch may process/cut a residual framework of the workpiece remaining after formation of the set of features.

Abstract: A system for controlling gas flow from a gas source, through a gas conduit, and to a plasma arc torch during a transition from a cold flow when no arc is present to a hot flow when an arc is provided by the present invention. The system comprises a first solenoid in communication with the gas source, a second solenoid disposed proximate the plasma arc torch, and a bypass circuit in communication with the gas source and the second solenoid. The bypass circuit comprises a bypass solenoid that controls the gas pressure within the gas conduit to reduce gas flow fluctuations when transitioning from cold flow to hot flow. Additional gas control systems and methods are also provided that cause the gas pressure to be higher during cold flow, prior to arc ignition, which overcomes the rapid drop in flow that typically occurs during the transition to hot flow.

Abstract: A system for controlling gas flow from a gas source, through a gas conduit, and to a plasma arc torch during a transition from a cold flow when no arc is present to a hot flow when an arc is provided by the present invention. The system comprises a first solenoid in communication with the gas source, a second solenoid disposed proximate the plasma arc torch, and a bypass circuit in communication with the gas source and the second solenoid. The bypass circuit comprises a bypass solenoid that controls the gas pressure within the gas conduit to reduce gas flow fluctuations when transitioning from cold flow to hot flow. Additional gas control systems and methods are also provided that cause the gas pressure to be higher during cold flow, prior to arc ignition, which overcomes the rapid drop in flow that typically occurs during the transition to hot flow.

Abstract: A solenoid control and safety circuit suitable for use in connection with contact start, plasma-arc torches. The system monitors a voltage to determine when to open an air control solenoid as part of a contact starting process. If a proper voltage is sensed, a gas solenoid is opened to allow airflow to separate the contact starting elements. The system also includes a circuit that monitors a gas pressure switch to determine whether sufficient pressure exists to separate the contact start elements after a contact start process has been initiated. The circuit removes power if it senses insufficient pressure. Also disclosed is a circuit that monitors a differential voltage between the electrode and the tip to determine if the elements remain in contact after airflow has been provided to the torch head.

Abstract: A solenoid control and safety circuit suitable for use in connection with contact start, plasma-arc torches. The system monitors a voltage to determine when to open an air control solenoid as part of a contact starting process. If a proper voltage is sensed, a gas solenoid is opened to allow airflow to separate the contact starting elements. The system also includes a circuit that monitors a gas pressure switch to determine whether sufficient pressure exists to separate the contact start elements after a contact start process has been initiated. The circuit removes power if it senses insufficient pressure. Also disclosed is a circuit that monitors a differential voltage between the electrode and the tip to determine if the elements remain in contact after airflow has been provided to the torch head.

Abstract: A pilot arc circuit for a plasma torch establishes a pilot arc current in the channel between the torch electrode and torch tip at a first target level which is greater than a predetermined minimum current sufficient to maintain a stable pilot arc. After a period of time following pilot arc initiation, the pilot arc current is reduced to a second target level which is greater than or equal to the predetermined minimum current so that damage to the torch is reduced by minimizing wear on the parts. The pilot arc current is established and maintained as a function of a pilot arc reference signal. Pulsing the pilot arc current assists in main arc transfer and enhances pilot arc stability.

Abstract: An electronic circuit for a plasma arc torch that initiates the transfer of a pilot arc into an operating arc before operating current is sensed in a workpiece. The electronic circuit includes a power circuit output inductor, and a pilot circuit having a disconnect in series with the pilot electrode of the plasma torch. An oscillator is coupled to the disconnect to periodically open-circuit the pilot circuit before current is detected in the workpiece by a current sensor. The periodic cessation of current caused by the disconnect causes the output inductor to create a voltage spike that assists in the transfer by attempting to establish the operating arc between the electrode and the workpiece. Optionally, a pilot inductor in the pilot circuit provides transitory power to sustain the pilot arc during the time the pilot current source is ceased, should arc transfer not occur.

Abstract: Plasma cutting apparatus (10) for use in cutting a material (M). A torch (12) cuts the material. A control unit (14) controls the cutting operation performed by the torch and includes a control module (16) in which the control unit is housed. At least one power unit (18) supplies power to the cutting torch, the application of this power being controlled by the control unit. Each power unit includes a power module (24) in which the power unit is housed. A cooling unit (54) for cooling the torch is also available. The cooling unit includes a cooling module (56). The control module, power module(s), and coolant module are removably stackable one on top of the other.

Abstract: A plasma arc torch having new electronic circuit concepts wherein main current regulated power means regulates the pilot current prior to main arc transfer. Further, the circuit may contain two inductors to which DC current initially flows but is interrupted upon main arc transfer such that one inductor maintains the pilot arc while the current in the second inductor forces the establishment of the transferred arc. Also, advantages are presented in pulsing the cutting arc as well as pulsing the pilot arc.

Abstract: A plasma arc torch having new electronic circuit concepts wherein main current regulated power means regulates the pilot current prior to main arc transfer. Further, the circuit may contain two inductors to which DC current initially flows but is interrupted upon main arc transfer such that one inductor maintains the pilot arc while the current in the second inductor forces the establishment of the transferred arc. Also, advantages are presented in pulsing the cutting arc as well as pulsing the pilot arc.