Thermal Dynamics Corporation

The Esab Group Inc.

Victor Equipment Company

David A Tatham

Dennis J Solley

Christopher John Conway

Kevin D Horner-Richardson

Roger W Hewett

Nakhleh A Hussary

Andrew J Raymond

Fred A Rogers

Daniel Wayne Barnett

Roger H Lambert

Thierry Renault

Daniel A Cote

Ryan T Lynaugh

Raymond G Wilkins

Stephen W Norris

James M Gregorich

Douglass A Demers

Dirk Ott

John A Boisvert

Michael Wolfinger

Geoffrey H Putnam

David M Morris

Michael Sawchik

Leonid Pekker

Jake Brandis

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.

Electromechanical linearly actuated electrode

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.

Automated gas cutting system with auxiliary torch

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.

Gas flow pre-charge for a plasma arc torch

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.

Solenoid control and safety circuit system and method

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.

Plasma torch pilot arc circuit

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. If transfer occurs, the pilot circuit is kept open-circuited, else the pilot circuit is closed until current is sensed in the workpiece indicative of arc transfer or the oscillator again open-circuits the pilot regulator disconnect.

Plasma torch arc transfer circuit

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.

Modular, stackable plasma cutting apparatus

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.

Plasma torch electronic pulsing circuit

Growing community of inventors

Enfield, NH, United States of America

David A Tatham