Abstract: Systems and methods for controlling a heater to drive a load temperature to approximate a setpoint. At the beginning of each ½ AC cycle, a sigma delta modulation algorithm is computed to determine whether the AC cycle should be turned on or off. The running estimate of the past actual duty cycle is compared to the desired output duty cycle, and the difference between the two is used to adjust the next ½ cycle's output. This results in a pseudo-random pulse sequence output which does not contain significant periodic components that could cause undesirable small periodic thermal ‘ripples’ on the element being heated.

Abstract: The invention relates to a method for operation of a steam plasma burner (6), comprising a cathode (22) and an anode (24) in the form of a nozzle (23) for machining a workpiece (20), wherein during the operation a current is applied between the cathode (22) and the anode (24) and/or the workpiece (20) by means of a power supply (2). After starting a pilot arc between the cathode (22) and the anode (24) by approaching the steam plasma burner (6) to the workpiece (20), a working arc is formed between the cathode (22) and the workpiece (20) and the pilot arc is extinguished by switching off the power supply (2) to the anode (24) and the current increased to a given working current. In order to achieve an optimal operation of a steam plasma burner, the voltage (UUE) between the cathode (22) and the workpiece (20) is monitored during working operation and the power supply (2) reconnected to the anode (24) to reform the pilot arc when the voltage (UUE) exceeds a threshold (IUEs).

Abstract: A cutting apparatus (1) includes a base (5) having upwardly extending first and second ends (10, 15) between which spaced elongate sides extend (20, 25). The ends and sides (10, 15, 20, 25) being located in a plane. The plane being inclined by an acute angle to a vertical plane. A cutting device (35) is provided to cut sheet material supported on the base (5). The device (1) is mounted on and moveable relative to the sides and ends (10, 15, 21, 25). Means (30) urges the cutting device (35) to desired locations relative to the base (5) thereby enabling the device (1) to cut the sheet material at desired locations.

Abstract: A plasma generating electrode capable of generating plasma with a high energy level by using a small amount of electric power is provided. The plasma generating electrode includes at least a pair of unit electrodes including a unit electrode as an anode and a unit electrode as a cathode, and can generate plasma by applying voltage, the unit electrode as an anode and the unit electrode as a cathode being disposed facing each other, and at least the unit electrode as an anode having a plate-like ceramic dielectric and a conductive film disposed in the ceramic dielectric, wherein the unit electrode as a cathode can emit secondary electrons in a number five times or greater than the number of cations (primary particles) which it receives when the cations produced in the process of plasma generation collide therewith.

Abstract: A metering system and associated method for supplying gas to a torch are provided. The metering system includes a controller that is configured to adjust a pressure regulator according to the pressure and flow rate of the gas delivered to the torch. For example, the torch can be a plasma arc torch that has an electrode positioned in a nozzle and operates in a working mode by providing an arc from the electrode to a workpiece. In a first mode of operation, the metering system can provide a gas to the torch by adjusting the pressure regulator according to the pressure downstream of the pressure regulator. In a second mode of operation, the metering system can provide adjust the pressure regulator according to the flow rate of the gas through a flow transducer in series with the pressure regulator.

Abstract: Methods and systems for transferring a plasma arc from between an electrode and a tip to between an electrode and a workpiece and back as dictated by the conditions at the cutting arc are provided. The present disclosure allows for arc transfer detection without use of a current sensor at the workpiece or knowledge of a precise pilot circuit limit value through a novel plasma arc control circuit. In one embodiment, the plasma arc control circuit provides a programmable current source and a current sink configured to limit current in a pilot arc control circuit. The pilot arc circuit may be configured to signal its limiting status to a controller, which may switch the pilot arc control circuit in or out of the current path. Certain embodiments may include a pulse width modulation control in the pilot arc control circuit for controlling current flow through the pilot arc circuit.

Abstract: A vacuum plasma generator (VPG) includes an output connector for electrical connection of the VPG to at least one electrode of a plasma chamber. The VPG includes a mains connector for connection of the VPG to a mains power supply, a mains input filter coupled to the mains connector, a voltage converter coupled to the mains input filter for generating an output signal, a voltage converter control input for connection to a voltage converter control, a shield that surrounds at least the voltage converter, the mains power supply, and the mains input filter, and a connection device that provides an electrical connection between the shield and the plasma chamber.

Abstract: A method and apparatus for controlling power output of a capacitatively-coupled plasma are provided. A detector is disposed on the power delivery conduit carrying power to one electrode to detect fluctuations in power output to the electrode. The detector is coupled to a signal generator, which converts the RF input signal to a constant control signal. A controller adjusts power input to the RF generator by comparing the control signal to a reference.

Abstract: A system and method for producing braces for a cavity die having a predetermined shape are disclosed. The system includes an input file containing information about the shape of the cavity die and a bracing program running on a computer. The bracing program produces an output file based on the input file and brace parameters. The output file includes information about the design of the braces. The computer instructs a brace-making machine to produce the braces based on the information in the output file. The method includes the steps of: a) providing input information about the shape of the cavity die and the brace parameters to the computer; b) processing the input information by the computer to produce an output file containing information about the design of the braces; and c) producing the braces in accordance with the information from the output file.

Abstract: A system and method for identifying a torch assembly associated with a thermal processing system can include a detector that detects a multi-bit binary signal based on a plurality of open circuits or closed circuits with the thermal processing system. Each representative binary signal can comprise an individual physical component. The system can also include a control mechanism in communication with the detector, the control mechanism identifying at least one characteristic of the torch assembly based upon the multi-bit binary signal.

Abstract: The invention relates to a water-vapor plasma torch (7) for cutting a workpiece (21), comprising a feed line (8) for a liquid (9), a heating device (22), and an evaporator (23) for forming a gas (20) from the liquid (9), a cathode (24) detachably connected to a movably mounted piston rod (25), and a nozzle (26) with an outlet opening (27) for the gas (20), as well as to a wear-detection and process-control method to be used with such a water-vapor plasma torch (7). To create such a water-vapor plasma torch (7) including wearing-part detection, at least one temperature sensor (28) is arranged within the piston rod (25), said temperature sensor being connected to a control unit (4), so that a wear of the cathode (24) and the nozzle (26) can be concluded from the temperature values detected, and that the control of the water-vapor plasma cutting process is influenceable.

Abstract: A plasma device including a power source for creating an AC output signal with a matrix transformer between said power source and a series circuit comprising a first lead and a second lead. The matrix transformer including at least two modules with a first primary portion formed of first and second tubes connected at one end and a second primary portion formed of third and fourth tubes connected at one end, with said third and fourth tubes mounted in, and electrically isolated from, said first and second tubes, respectively, where said concentric tubes define generally parallel elongated passages through the module. A secondary winding is wrapped through the elongated passages of each module.

Abstract: A system is provided that includes a torch power unit, wherein the torch power unit includes a motor and a digital device coupled to the motor and configured to control the motor. A method of operation is provided that includes controlling one or more aspects of a torch power unit via a microprocessor, a digital signal processor, or a field programmable gate array, or a combination thereof. In another embodiment, a system is provided that includes a torch power unit that includes a torch, one or more components comprising a generator, a power converter, a compressor, a motor, a wire feeder, or a combination thereof, and a microprocessor configured to control the one or more components.

Abstract: A system is provided that includes a torch power unit that includes a compressor and a controller configured to adjust output of the compressor in response to feedback comprising compressor output, or altitude, or atmospheric pressure, or a combination thereof. A method is provided that includes adjusting operational parameters of a torch power unit to account for environmental conditions affecting performance of the torch power unit. A method of manufacturing a portable cutting torch system is also provided. Another system is provided that includes a plasma cutting circuit, a compressor, a motor coupled to the compressor, an interface, and an environmental feedback controller.

Abstract: Systems and methods are provided for a torch power system having a high power density. In one embodiment, a system is provided that includes a torch power unit having a compressor and power electronics that include one or more power converters, wherein the torch power unit has a power output density of at least 2 watts per cubic inch, 80 watts per pound, or a combination thereof. A power conversion assembly for a torch power unit is provided that includes a single circuit board, a torch power converter mounted on the single circuit board, and a non-torch power converter mounted on the single circuit board. An electrical torch system is also provided that includes a circuit board and a power converter coupled to the circuit board, wherein the power converter includes a planar transformer, a foil wound transformer, or a combination thereof.

Abstract: A plasma supply device includes a full bridge circuit that is connected to a DC power supply and that has two half bridges each with two series connected switching elements. The plasma supply device further includes a primary winding of a power transformer connected to centers of the half bridges between the switching elements. The primary winding includes a tapping connectable to an alternating current center between the potentials of the DC power supply.

Abstract: In a processing apparatus for performing a specified process on a target object at a predetermined process pressure, the apparatus includes an evacuable processing chamber having a gas exhaust port formed in a bottom portion thereof; a mounting table provided within the processing chamber for holding the target object; a pressure control valve connected to the gas exhaust port, the pressure control valve including a slide-type valve body for changing an area of an opening region of a valve port; and a gas exhaust system connected to the pressure control valve. The pressure control valve is eccentrically arranged such that a center axis of the mounting table lies within an opening region of the pressure control valve formed over a practical use region of a valve opening degree of the pressure control valve.

Abstract: A plasma arc generation system includes a power module operably engaged with a plasma arc torch head portion and adapted to provide an electrical current for causing an arc at the torch head portion or generating a plasma. A cooling device is operably engaged with the power module so as to direct a fluid thereto for cooling the power module. The cooling device is configured such that the fluid directly contacts the power module to receive heat therefrom generated by the power module. Associated systems and methods are also provided.

Abstract: For responding to an arc discharge in a plasma process (PP), a parameter of the plasma process is monitored to detect arc discharges occurring in the plasma. After detection of an arc discharge, a first countermeasure for the suppression of arc discharges is executed. After completion of the first countermeasure, a delay time period is allowed to elapse before the parameter is rechecked. In the event that after conclusion of the variable delay time period an arc discharge is detected, a second countermeasure for the suppression of arc discharges is executed.

Abstract: A method of creating a simplified equivalent circuit model of a plasma processing system, including an electrical measuring device, a lower electrode, an upper electrode, and a signal generator device is described. The method includes creating a simplified equivalent circuit equation, including a set of variables, of the plasma processing system, wherein the electrical measuring device comprises a first subset of variables, the lower electrode comprises a second subset of variables, the upper electrode comprises a third subset of variables, and the signal generator device comprises a forth subset of variables. The method also includes generating a set of signals, each of the set of signals being generated at a different frequency, wherein the signal generator device is coupled to the electrical measuring device, the lower electrode, and the upper electrode.

Abstract: A plasma processing apparatus performs a desired plasma processing on a target substrate by using a plasma generated from a processing gas by forming a high frequency electric field in an evacuable processing chamber having an electrode. The plasma processing apparatus includes a high frequency power supply for outputting a high frequency power; and a central power feeder connected with a central portion of a rear surface of the electrode to supply the high frequency power from the high frequency power supply to the electrode. The plasma processing apparatus further includes a peripheral power feeder connected with a peripheral portion of the rear surface of the electrode in parallel with the central power feeder to supply the high frequency power from the high frequency power supply to the electrode.

Abstract: A portable plasma arc torch system can be used for processing materials. The system includes a replaceable or rechargeable power source and replaceable or rechargeable gas source. A controller communicates with at least one of the power source or the gas source. A plasma delivery device received via the controller current from the power source and gas from the gas source to generate a plasma arc at an output of the plasma delivery device. The plasma arc can be used to process materials such as metallic workpieces. The plasma arc torch can include a wearable portable assembly which includes the replaceable or rechargeable power and gas source. A plasma delivery device receives current from the power source in the assembly and gas from the gas source in the assembly to generate a plasma arc.

Abstract: A lightweight and compact plasma cutting system includes a power source having an inverter and a non-adjustable regulator enclosed within the power source. The inverter is configured to generate a power signal suitable for a plasma arc process and the non-adjustable regulator is preconfigured to deliver a fixed gas flow to a plasma torch for the plasma arc process.

Abstract: An atomic oxygen generator/sprayer is invented. An array of three magnetized torches running at 60 Hz is used to generate non-thermal plasma; thus, the plasma effluent has relatively low temperature (touchable) and yet contains high energy electrons (>5 eV) capable to dissociate oxygen molecules to atomic oxygen. The emission spectroscopy of the torch indicates that the plasma effluent carries an abundance of reactive atomic oxygen (RAO), which can effectively kill all kind microbes. A cap holding three pairs of rectangular permanent magnets is used to spread torches laterally into fan shape, which extends to a width exceeding 100 mm. The flux of RAO exceeds 2×106 cm?2 sec?1; its flow speed exceeds 20 m/s and it reaches out more than 20 mm. This invention is suitable for applications such as sterilizing carpets, clothes, and bed sheets.

Abstract: The present invention is directed to a method and arrangement for controlling a glow discharge plasma in a gas or gas mixture under atmospheric conditions, in a plasma discharge space comprising at least two spaced electrodes in which at least one plasma pulse having an absolute pulse maximum is generated by applying an AC plasma energizing voltage to the electrodes causing a plasma current and a displacement current. The plasma is controlled by providing a relative decrease of the displacement current after the pulse maximum. In a preferred embodiment, the energizing voltage is applied through a series circuit including a choke coil and a non-saturable inductor.

Abstract: An arc detector is provided for a plasma processing system including a HF power source, a plasma processor, and a voltage/current signal detector. The arc detector includes a calculator for the phase difference between the AC voltage signal and the AC current signal, a calculator for an effective voltage based on the AC voltage signal, a calculator for an effective current based on the AC current signal, an FFT processor for the frequency spectrum of the AC voltage or current signal, and an arc analyzer connected to the phase difference calculator, effective voltage calculator, effective current calculator, and FFT processor. The arc analyzer calculates the plasma processor's impedance based on the calculated phase difference, effective voltage, and effective current. The arc analyzer monitors arcs in the plasma processor, based on the fluctuation rate of the calculated impedance and the output level of a frequency component in the spectrum. (FIG.

Abstract: To detect arc discharges occurring in a plasma, a parameter of the plasma process is determined, and after a first period of time following the detection of an arc discharge the parameter is again determined. In the event that after the first period of time no arc discharge is detected, a first arc suppression countermeasure for suppression of arc discharges is executed.

Abstract: Systems and methods for controlling a heater to drive a load temperature to approximate a setpoint. At the beginning of each ½ AC cycle, a sigma delta modulation algorithm is computed to determine whether the AC cycle should be turned on or off. The running estimate of the past actual duty cycle is compared to the desired output duty cycle, and the difference between the two is used to adjust the next ½ cycle's output. This results in a pseudo-random pulse sequence output which does not contain significant periodic components that could cause undesirable small periodic thermal ‘ripples’ on the element being heated.

Abstract: An electrode for a plasma arc cutting torch which minimizes the deposition of high emissivity material on the nozzle, reduces electrode wear, and improves cut quality. The electrode has a body having a first end, a second end in a spaced relationship relative to the first end, and an outer surface extending from the first end to the second end. The body has an end face disposed at the second end. The electrode also includes at least one passage extending from a first opening in the body to a second opening in the end face. A controller can control the electrode gas flow through the passages as a function of a plasma arc torch parameter. Methods for operating the plasma arc cutting torch with the electrode are disclosed.

Abstract: An electrode for a plasma arc cutting torch which minimizes the deposition of high emissivity material on the nozzle, reduces electrode wear, and improves cut quality. The electrode has a body having a first end, a second end in a spaced relationship relative to the first end, and an outer surface extending from the first end to the second end. The body has an end face disposed at the second end. The electrode also includes at least one passage extending from a first opening in the body to a second opening in the end face.

Abstract: In a main circuit 11 of the plasma cutter power supply device 6, a plurality of DC power units 14-1, . . . 14-n of low capacity are connected in parallel on their DC output sides, and are connected to a plasma torch 20. Each power unit 14-1, . . . 14-n can operate asynchronously and independently from each other. The power supply control device 6 controls the number of power units to be operated, and the intensity of output electrical current at which each of them is to be operated, according to the cutting conditions (the nature of the material to be cut, its thickness, and the cutting speed) and according to the number of power units which can be operated. If some of the power units are faulty, the power supply control device 6 controls the cutting conditions which can be accepted, according to the number of normal power units.

Abstract: A detection unit (8) is disposed for detecting the magnitudes of f1 and f2 frequency components of a composite signal which is passed through a center electrode cable (4). A detecting signal generating unit (9) generates a detecting signal corresponding to a gap between a nozzle (5) and a workpiece (6) from the magnitudes of the f1 and f2 frequency components of the composite signal, which are detected by the detection unit (8). As a result, even if plasma occurs in the gap between the nozzle (5) and the workpiece (6), the gap can be detected with a high degree of precision.

Abstract: A method of supplying a plasma torch with a gas, mixed gas or gas mixture, in which the volume flow of the gas, mixed gas or gas mixture is controlled, characterised in that the volume flow control is effected in combination with a pressure control of the gas, mixed gas or gas mixture in such a way that the pressure control is used to adjust the level of the total volume flow through the nozzle of the plasma torch, and the volume flow control is used to adjust the volume flow portions producing the total volume flow, taking the desired gas composition into account, and an arrangement for carrying out said method.

Abstract: A plasma processing apparatus is provided which processes a sample held on a sample table arranged in a process chamber in a vacuum container by using a plasma formed in the process chamber. The plasma processing apparatus comprises: paths arranged in the sample table in which a coolant is supplied and vaporized as it flows; a refrigeration cycle having the sample table, a compressor, a condenser and an expansion valve connected in that order and having the coolant circulate therein; coolant passages to cause the coolant that has passed through the expansion valve to branch and then merge with a coolant returning from the paths in the sample table toward the compressor; and a regulator to adjust an amount of coolant passing through the paths in the sample table and circulating in the refrigeration cycle and an amount of coolant branching and flowing through the coolant passages.

Abstract: A method and apparatus for reducing the gap resistance between two electrodes, such as the electrodes used fusion splicing one optical fiber to another, by injecting negative ions into the gas or gasses that are located between the electrodes. As a result, the voltage that is required to cause dielectric breakdown and initiation of the electrical arc is drastically reduced.

Abstract: An RF blocking filter isolates a two-phase AC power supply from at least 2 kV p-p of power of an HF frequency that is reactively coupled to a resistive heating element, while conducting several kW of 60 Hz AC power from the two-phase AC power supply to the resistive heating element without overheating, the two-phase AC power supply having a pair of terminals and the resistive heating element having a pair of terminals. The filter includes a pair of cylindrical non-conductive envelopes each having an interior diameter between about one and two inches and respective pluralities of fused iron powder toroids of magnetic permeability on the order of about 10 stacked coaxially within respective ones of the pair of cylindrical envelopes, the exterior diameter of the toroids being about the same as the interior diameter of each of the envelopes. A pair of wire conductors of diameter between 3 mm and 3.

Abstract: A signal processing portion obtains the reciprocal of a composite impedance of gap static capacitance and a plasma impedance, obtains composite static capacitance which is the sum of the gap static capacitance and a static capacitance component included in the plasma impedance from an imaginary part of the reciprocal, and obtains a resistance component included in the plasma impedance from a real part of the reciprocal. A gap detection device obtains the static capacitance component by using a model representing the characteristics of the reciprocal of the plasma impedance and the resistance component and obtains the gap static capacitance by subtracting the static capacitance component from the composite static capacitance. The gap detection device obtains a gap from the obtained gap static capacitance. Thus provided is a technique to detect a gap between a nozzle of a laser beam machine for outputting a laser beam and an object to be machined with high accuracy.

Abstract: A temperature unit to control a temperature of a device under test using a fluid includes a block disposed opposite the device under test and which defines a gap therebetween and through which the fluid passes across the device under test at a gap flow rate, and an actuator which moves the block. By adjusting the gap, the gap flow rate of the fluid flowing over the device under test changes so as to adjust the temperature of the device under test. Additionally, the block can be a heater block which generates heat receivable by the device under test across the gap such that the adjustment of the heater block by the actuator changes a thermal resistance across the gap.

Abstract: A method of thermally processing a material includes exposing the material to at least one pulse of infrared light emitted from a directed plasma arc to thermally process the material, the pulse having a duration of no more than 10 s.

Abstract: The invention relates to a surface treatment device comprising: electrodes (24a, 24b) that are used to initiate an electric arc of stabilised plasma (14); a stabilising channel (12) which is disposed in a body (10) in order to confine the electric arc of stabilised plasma; conduits (38, 39) which are disposed in the body and used to introduce a treatment gas Q1, uniformly distributed along the arc, upstream of the arc in a direction that is essentially perpendicular to axis A of said arc in such a way as to form an activated gas curtain (8); means for introducing a complementary treatment gas Q2 downstream of the electric arc; and a support (28) that is used to hold the object or material to be treated in place and to position the object or material surface to be treated in relation to the body (10).

Abstract: An arc suppression system for plasma processing comprising at least one sensor coupled to the plasma processing system, and a controller coupled to the at least one sensor. The controller provides at least one algorithm for determining a state of plasma in contact with a substrate using at least one signal generated from the at least one sensor and controlling a plasma processing system in order to suppress an arcing event. When voltage differences between sensors exceed a target difference, the plasma processing system is determined to be susceptible to arcing. During this condition, an operator is notified, and decision can be made to either continue processing, modify processing, or discontinue processing.

Abstract: A method in a plasma processing system for processing a semiconductor substrate is disclosed. The plasma processing system includes a plasma processing chamber and an electrostatic chuck coupled to a bias compensation circuit. The method includes igniting a plasma in a plasma ignition step. Plasma ignition step is performed while a first bias compensation voltage provided by the bias compensation circuit to the chuck is substantially zero and while a first chamber pressure within the plasma processing chamber is below about 90 mTorr. The method further includes processing the substrate in a substrate-processing step after the plasma is ignited. The substrate-processing step employs a second bias compensation voltage provided by the bias compensation circuit that is higher than the first bias compensation voltage and a second chamber pressure substantially equal to the first chamber pressure.

Abstract: A method and apparatus for automatically determining a consumable type when a consumable is disposed within an electrode holder of a welding-type system is disclosed. The invention includes a detector assembly that measures a physical characteristic of a connected consumable and provides feedback regarding that which is measured. From the feedback, the operating parameters of a welding-type process may be automatically prescribed.

Abstract: A method for operating a semiconductor processing apparatus that plasma-processes a semiconductor wafer mounted on a stage placed in a container using a plasma generated therein. The method includes setting a temperature of the semiconductor wafer, and controlling an operation of the semiconductor processing apparatus based on information about the temperature of the semiconductor wafer which is set.

Abstract: A method for processing a plurality of substrates in a plasma processing chamber of a plasma processing system, each of the substrate being disposed on a chuck and surrounded by an edge ring during the processing. The method includes processing a first substrate of the plurality of substrates in accordance to a given process recipe in the plasma processing chamber. The method further includes adjusting, thereafter, a capacitance value of a capacitance along a capacitive path between a plasma sheath in the plasma processing chamber and the chuck through the edge ring by a given value. The method additionally includes processing a second substrate of the plurality of substrates in accordance to the given process recipe in the plasma processing chamber after the adjusting, wherein the adjusting is performed without requiring a change in the edge ring.

Abstract: A torch cable in which both the electrical connection and the pneumatic connection can be made concurrently in one motion by coupling the end of the torch cable to the exterior of the supply unit. The coupling further includes a quick disconnect feature. The torch cable coupling is simple and inexpensive, using standard off-the-shelf components. The end of the cable comprises various components that are overmolded to form an electrically insulative body, e.g., made of urethane rubber compound. This molded body incorporates strain relief, is water resistant, protects the electrical plug, and stabilizes the electrical contacts. Gas, power and control are combined in one assembly. The pneumatic quick disconnect coupling is used as a latching mechanism for the entire assembly. The torch cable can be disconnected from the supply unit by simply releasing the quick disconnect coupling and then pulling the end of the torch cable away from the supply unit.

Abstract: A device to place an incision into matter with a harmonious plasma cloud. A radiofrequency generator system produces pulsed or continuous electromagnetic waveform which is transmitted by an active transmitter incising electrode tip. This generated electromagnetic wave is utilized to initiate a plasma cloud with processes such as thermal ionization and a photoelectric effect which then trigger an Avalanche Effect for charged atomic particles at the surface of the active transmitter incising electrode tip. This electromagnetic wave is impedance matched, frequency matched, power matched and tuned to the plasma cloud in order to sustain and control a harmonious plasma cloud with reduced atomic particle turbulence and chaos. This harmonious plasma cloud forms a coating over the surface of the active transmitter electrode tip as well as acts to reduce the energy needed from the power amplifier of our plasma cutting device.

Abstract: A metering system and associated method for supplying gas to a torch are provided. The metering system includes a controller that is configured to adjust a pressure regulator according to the pressure and flow rate of the gas delivered to the torch. For example, the torch can be a plasma arc torch that has an electrode positioned in a nozzle and operates in a working mode by providing an arc from the electrode to a workpiece. In a first mode of operation, the metering system can provide a gas to the torch by adjusting the pressure regulator according to the pressure downstream of the pressure regulator. In a second mode of operation, the metering system can provide adjust the pressure regulator according to the flow rate of the gas through a flow transducer in series with the pressure regulator.

Abstract: A system and associated method for determining an operational condition of a gas torch are provided. The system includes a diode device that is electrically connected between the workpiece and the nozzle. A sensing circuit is configured to provide an electric potential across the diode device and sense a resulting voltage characteristic of the condition of continuity of the system. For example, the sensing circuit can determine whether the nozzle is otherwise electrically connected to the workpiece and/or whether the nozzle is electrically connected to the electrode. The sensing circuit can determine the condition of continuity throughout the operation of the system, e.g., to verify the proper assembly of the torch, to verify proper movement of the electrode or nozzle, to verify that the torch is separated from the workpiece at start-up, and the like.

Abstract: Cutting quality of the product, in particular, hole cutting quality, in plasma arc cutting is improved. A control unit, which controls a plasma cutting apparatus for cutting a product from a plate material by moving a plasma torch at a cutting speed along a cutting path corresponding to the product shape to cut the plate material, while supplying an arc current and a plasma gas to the plasma torch and forming a plasma arc from a nozzle of the plasma torch to the plate material, conducts control so that, when a hole is cut, a cutting speed is lower, a value of the arc current value is smaller, and a plasma gas flow rate or pressure is less than those when a contour is cut.