EP3878244B1 - Frame for a cartridge for a plasma arc cutting system, method of cooling the plasma arc cutting system and method of manufacturing the frame - Google Patents
Frame for a cartridge for a plasma arc cutting system, method of cooling the plasma arc cutting system and method of manufacturing the frame Download PDFInfo
- Publication number
- EP3878244B1 EP3878244B1 EP19836670.0A EP19836670A EP3878244B1 EP 3878244 B1 EP3878244 B1 EP 3878244B1 EP 19836670 A EP19836670 A EP 19836670A EP 3878244 B1 EP3878244 B1 EP 3878244B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- frame
- cartridge
- electrode
- substantially cylindrical
- nozzle
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 17
- 238000000034 method Methods 0.000 title claims description 17
- 238000001816 cooling Methods 0.000 title claims description 9
- 238000005520 cutting process Methods 0.000 title description 20
- 239000012212 insulator Substances 0.000 claims description 16
- 239000004033 plastic Substances 0.000 claims description 16
- 229920003023 plastic Polymers 0.000 claims description 16
- 239000012530 fluid Substances 0.000 claims description 8
- 229910001369 Brass Inorganic materials 0.000 claims description 7
- 239000010951 brass Substances 0.000 claims description 7
- 238000009434 installation Methods 0.000 claims description 5
- 239000012809 cooling fluid Substances 0.000 claims 2
- 239000007789 gas Substances 0.000 description 21
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 17
- 229910052802 copper Inorganic materials 0.000 description 17
- 239000010949 copper Substances 0.000 description 17
- 239000000463 material Substances 0.000 description 14
- 229910052782 aluminium Inorganic materials 0.000 description 12
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 12
- 229920001169 thermoplastic Polymers 0.000 description 11
- 239000004416 thermosoftening plastic Substances 0.000 description 11
- 238000013461 design Methods 0.000 description 10
- 239000004020 conductor Substances 0.000 description 5
- 238000010168 coupling process Methods 0.000 description 5
- 238000005859 coupling reaction Methods 0.000 description 5
- 238000002844 melting Methods 0.000 description 5
- 230000008018 melting Effects 0.000 description 5
- 229910052751 metal Inorganic materials 0.000 description 5
- 239000002184 metal Substances 0.000 description 5
- 230000008901 benefit Effects 0.000 description 4
- 239000000112 cooling gas Substances 0.000 description 4
- 230000008878 coupling Effects 0.000 description 4
- 238000002955 isolation Methods 0.000 description 4
- 238000003754 machining Methods 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 238000004891 communication Methods 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 206010011906 Death Diseases 0.000 description 2
- 239000004696 Poly ether ether ketone Substances 0.000 description 2
- 239000004963 Torlon Substances 0.000 description 2
- 230000000712 assembly Effects 0.000 description 2
- 238000000429 assembly Methods 0.000 description 2
- JUPQTSLXMOCDHR-UHFFFAOYSA-N benzene-1,4-diol;bis(4-fluorophenyl)methanone Chemical compound OC1=CC=C(O)C=C1.C1=CC(F)=CC=C1C(=O)C1=CC=C(F)C=C1 JUPQTSLXMOCDHR-UHFFFAOYSA-N 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 238000005553 drilling Methods 0.000 description 2
- 238000001746 injection moulding Methods 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 229920003223 poly(pyromellitimide-1,4-diphenyl ether) Polymers 0.000 description 2
- 229920002530 polyetherether ketone Polymers 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 229920001187 thermosetting polymer Polymers 0.000 description 2
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 description 1
- 229910000881 Cu alloy Inorganic materials 0.000 description 1
- 239000004697 Polyetherimide Substances 0.000 description 1
- 229920002873 Polyethylenimine Polymers 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229920003997 Torlon® Polymers 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 238000004026 adhesive bonding Methods 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 229910052786 argon Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 238000002788 crimping Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000003365 glass fiber Substances 0.000 description 1
- 229910052735 hafnium Inorganic materials 0.000 description 1
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 230000013011 mating Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910001092 metal group alloy Inorganic materials 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 239000002991 molded plastic Substances 0.000 description 1
- 210000002445 nipple Anatomy 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 239000000615 nonconductor Substances 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 229920002312 polyamide-imide Polymers 0.000 description 1
- 229920001601 polyetherimide Polymers 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000005382 thermal cycling Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
- H05H1/00—Generating plasma; Handling plasma
- H05H1/24—Generating plasma
- H05H1/26—Plasma torches
- H05H1/32—Plasma torches using an arc
- H05H1/34—Details, e.g. electrodes, nozzles
- H05H1/3468—Vortex generators
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
- H05H1/00—Generating plasma; Handling plasma
- H05H1/24—Generating plasma
- H05H1/26—Plasma torches
- H05H1/32—Plasma torches using an arc
- H05H1/34—Details, e.g. electrodes, nozzles
- H05H1/3423—Connecting means, e.g. electrical connecting means or fluid connections
Definitions
- the invention relates generally to the field of plasma arc cutting systems and processes. More specifically, the invention relates to methods and apparatuses for simplifying, optimizing and decreasing the time and cost of cutting through the use of improved consumable cartridges.
- a plasma torch generally includes an arc emitter (e.g., an electrode), an arc constrictor or constricting member (e.g., a nozzle) having a central exit orifice mounted within a torch body, electrical connections, passages for cooling, and passages for arc control fluids (e.g., plasma gas).
- the torch produces a constricted ionized jet of a gas with high temperature and high momentum.
- Gases used in the torch can be nonreactive (e.g., argon or nitrogen) or reactive (e.g., oxygen or air).
- a pilot arc is first generated between the arc emitter (cathode) and the arc constrictor (anode).
- Generation of the pilot arc can be by means of a high frequency, high voltage signal coupled to a DC power supply and the torch or by means of any of a variety of contact starting methods.
- EP3334556 discloses an exemplary frame for a cartridge configured for installation into a plasma arc torch.
- the invention discloses a frame for a cartridge configured for installation into a plasma arc torch, according to claim 1.
- the invention discloses a method of cooling a plasma arc torch according to claim 7.
- the substantially cylindrical metallic core provides geometric stability, preventing the frame from changing shape, which could cause the electrode to cease and not slide, and/or cause the nozzle to fall off.
- the invention discloses a method of manufacturing the frame of claim 1.
- Advantageous embodiments are disclosed in the dependent claims.
- FIG. 1 is a cross-sectional schematic illustration of a cartridge 100 for a plasma arc cutting system, according to an illustrative embodiment useful to understand the invention.
- the cartridge 100 has a first end 104, a second end 108, and a substantially hollow frame 112 having a first section 112A toward the first end 104 and a second section 112B toward the second end 108.
- the cartridge 100 also includes an arc emitter 120, an arc constrictor 124, and a resilient element 128.
- the arc emitter 120 is located within the frame 112 and is translatable relative to the frame 112.
- the arc constrictor 124 forms a part of the frame 112 (e.g., at the second end 108, but in some embodiments can be attached to the frame 112).
- the resilient element 128 is in physical communication with the frame 112, e.g., is in direct physical communication with the first section 112A.
- the resilient member 128 is a contact start spring element affixed to the arc emitter 120.
- the resilient element 128 can be configured to pass a pilot current from the frame 112 to the arc emitter 120.
- the resilient element 128 can bias the arc emitter 120 toward one of the first end 104 or the second end 108 to facilitate ignition at or near the arc emitter 120.
- the arc emitter 120 can be an electrode and can include a highly emissive element 122 such as a hafnium insert.
- the first section 112A and second section 112B are joined at an interface 132 to form a substantially hollow chamber.
- the interface 132 provides a coupling force (F coupling ) that secures the first section 112A and the second section 112B together.
- the resilient member 128 can impart a separating force (F separating ) that biases the arc emitter 120 toward at least one of the first section 112A or the second section 112B.
- the separating force can have a magnitude that is less than a magnitude of the coupling force.
- the coupling force is provided at the interface 132 by at least one of a static frictional force, an adhesive force, or a normal force (e.g., a force countering a downward gravitational force) provided at a notch 136 of the interface 132.
- the coupling force is stronger than is possible for a person to overcome by hand, either intentionally or inadvertently.
- the frame 112 includes at least one of a metal (e.g., aluminum) or other thermally conductive material. In some embodiments, the frame 112 is formed by molding. In some embodiments, the frame 112 is anodized (e.g., includes anodized aluminum, as set forth more fully below). In some embodiments, the frame 112 includes an electrical insulator, for example anodized aluminum and/or thermoplastics (e.g., PEEK, Torlon, Vespel, etc.). In some embodiments, at least one of the first end 104 or the second end 108 of the frame 112 includes a threaded region shaped to engage a complementary component. In some embodiments, the electrode 120 includes the resilient element 128 such as a spring.
- the resilient element 128 such as a spring.
- an external surface of the cartridge 100 is shaped to connect to, or mate with, a retaining cap or a cartridge cap (not shown).
- the retaining cap is replaceable, threaded, and/or snap-on.
- the cartridge cap can be disposed about (e.g., can surround) the second end 108 of the frame 112.
- the cartridge cap can be shaped to contact the arc emitter 120 and to retain the arc emitter 120 within the frame 112.
- the cartridge cap can define an aperture of the arc emitter 120.
- the cartridge cap can include a fluid sealing surface disposed about a circumference of the aperture of the arc emitter 120.
- the cartridge cap substantially orients the electrode 120 and retains the electrode 120 within the cartridge 100.
- the cartridge cap includes a seal.
- the cartridge 100 can be a "consumable" cartridge or assembly of consumable components, e.g., the cartridge 100 can be replaced as a unit after it reaches the end of its useful life.
- the cartridge 100 can be a sealed unit that is not intended to have individual component parts replaced.
- individual components are irremovably disposed within or integrated into the cartridge 100.
- at least a portion of the electrode 120 and the contact start spring element 128 can be irremovably disposed within the frame 112, e.g., sealed within the frame 112 and/or not intended to be removed or replaced by an operator.
- the cartridge 100 is a consumable component.
- the components e.g., frame 112 and arc constrictor 124) may be connected via press fits or other like means with tight tolerances and will degrade, fracture, or fail if separated.
- FIG. 2A is an isometric illustration of a unitary cartridge 200 for a plasma arc cutting system, according to an illustrative embodiment useful to understand the invention. Visible from the exterior are a plastic exterior section 204, a metallic exterior section 208, and a copper exterior section 212 (e.g., a nozzle shield).
- the plastic exterior section 204 and the metallic exterior section 208 are joined at a junction 206. In some embodiments, the junction 206 is included in or near a tapered region.
- the plastic exterior section 204 is a retaining cap.
- the metallic exterior section 208 is a shield insulator.
- the metallic exterior section 208 is formed substantially of a material other than copper.
- the copper exterior section 212 is formed of a pure or substantially pure copper or copper alloy.
- the components of the cartridge 200 are seen in more detail in Figure 2B , described below.
- FIG. 2B is a cross-sectional illustration of a unitary cartridge 200 for a plasma arc cutting system, according to an illustrative embodiment useful to understand the invention.
- additional elements of the cartridge 200 are visible, including a nozzle body 216, a nozzle orifice 218, an electrode 220 having an emitting element 222, an insulator sleeve 224 having an elongated portion 224A, a resilient element 226, and an electrode contact button 236 (e.g., made of brass).
- the nozzle body 216 can be formed from a conductive material (e.g., a highly conductive material such as aluminum) and can be attached to (e.g., can be in direct physical contact with) other parts of the cartridge 200.
- the nozzle body 216 is in thermal communication with certain parts of the cartridge 200 (e.g., via thermal conduction) but electrically isolated from other parts.
- the nozzle body 216 can function as a heat sink for the nozzle orifice 218 while remaining electrically isolated from the nozzle shield 212.
- Such a configuration can enhance cooling performance (for example, of the nozzle and the electrode) and reduce manufacturing costs by comparison to previously used materials (e.g., as Vespel TM ).
- the cartridge has a region with a thermal conductivity of between about 200-400 Watts per meter per degree Kelvin (for example, aluminum may have a thermal conductivity of between 200-250 W/m-°K, while copper may have a thermal conductivity of between 350-400 W/m-°K).
- the consumable cartridge has a heat capacity to current ratio of 2-4 W/m-°K-A.
- the nozzle body 216 includes a set of inlet swirl holes 228 (e.g., swirl holes 228A and 228B).
- the set of inlet swirl holes 228 includes five swirl holes, or optionally between three and ten swirl holes.
- the swirl holes 228 can be radially offset to impart a swirl flow (e.g., radial and tangential velocity components) to gases flowing therethrough (e.g., a shield gas, plasma gas, and/or a plenum gas).
- a swirl flow e.g., radial and tangential velocity components
- gases flowing therethrough e.g., a shield gas, plasma gas, and/or a plenum gas.
- the nozzle body 216 provides the swirl function previously provided by a swirl ring, thus eliminating the need for a traditional swirl ring.
- the nozzle body 216 is formed via a molding process, thus eliminating the need for expensive and time-consuming drilling procedures to create the swirl holes.
- the nozzle shield 212 includes an angle 232 that helps redirects fluid flow away from the plasma arc during operation.
- FIG. 2C is a cross-sectional illustration of a unitary cartridge 240 for a plasma arc cutting system, according to an illustrative embodiment useful to understand the invention.
- the unitary cartridge 240 can be similar in many respects to the cartridge 200 shown in Figure 2B but can differ in certain other respects.
- the cartridge 240 utilizes a stamped torch interface 250 (e.g., a stamped pieces of copper) having a cross-sectional "T"-shape.
- the interface 250 can allow the electrode to slide more freely than in the Figure 2B configuration, which uses an electrode with a nipple feature that forms a mating surface with the spring.
- the cap and the nozzle body have been opened to ease manufacture and allow the electrode to slide freely into the nozzle body during cartridge assembly.
- the spring can then rest on the electrode, and the stamped torch interface 250 can use a small tab feature 252 to snap readily into the nozzle body, securing the electrode therein.
- Such a configuration avoids the need to press fit multiple pieces together (and, in turn, avoids the need to have to achieve tight tolerances between pieces) and/or the need to assemble different pieces of the torch from different directions.
- a manufacturer can simply slide the electrode into place in one step.
- the cartridge 240 uses a molded, slotted swirl feature 266 to achieve the swirling function instead of using holes drilled in the nozzle body.
- gas flows out of the slots 266 and into the plasma chamber to form the swirl gas about the plasma arc.
- gas may also flow through molded gas shield channel 254, further cooling the nozzle body.
- Slots 266 form a set of swirl holes once the nozzle body, nozzle orifice, and/or nozzle liner are connected. Gas delivered to the slots is conveyed from the torch through a chamber defined by an internal surface of the nozzle body and an external surface of the nozzle liner (which, in combination, form the swirl holes).
- Such a configuration eliminates post-process machining steps and the associated expenses.
- the cartridge 240 includes a radial swage connection 258 between the nozzle orifice and the nozzle body.
- the radial swage connection 258 provides a robust connection interface to allow contact to be maintained between the nozzle orifice and the nozzle body, but also exposes significant surface area for heat to be conducted from the nozzle orifice to the nozzle body.
- the electrode sleeve is removed and replaced with a more traditional heat exchanger.
- FIG. 2D is a sectioned illustration of a plasma arc torch cartridge frame 280 having an overmolded plastic casing 282, according to the invention.
- the frame 280 includes a hollow body 284 adapted to receive a translatable contact start electrode.
- the body 284 has an internal surface 286 and an external surface 288.
- the body 284 includes a substantially cylindrical metallic core 290, which can be formed by stamping.
- the body 284 also includes the electrically insulative overmolded plastic (such as a thermoset or thermoplastic) casing 282, which at least substantially surrounds a circumference of a distal end of the substantially cylindrical metallic core 290.
- the body 284 also includes a set of flow passages 292 (e.g., at a distal end of the cartridge frame 280, as shown) fluidly connecting the external surface 288 and the internal surface 286.
- the flow passages 292 are offset to impart a swirling fluid flow pattern to plasma gases passing therethrough.
- the passages impart a swirling flow to a plasma gas entering into the plasma chamber into the cartridge, a portion of the plasma moving distally to generate a plasma arc and a portion of the gas moving proximally to cool the electrode.
- the flow passages 292 can be formed entirely within the plastic, e.g., by molding, and can enable crimping with another cartridge or torch component, e.g., the proximal end of a nozzle or shield (not shown).
- the crimped component can form part of the swirling flow passages 292.
- the cylindrical metallic core 290 helps to overcome certain thermal cycling and overheating issues with using molded plastics in a swirl ring.
- plastics used in this context can exhibit a localized melting of the inner diameter, e.g., when the electrode is close to end of its life. At this point the electrode temperature can be higher than the melting point of the plastic used, causing it to melt and deform. Under these circumstances, the electrode in turn can be prevented from moving freely inside the swirl ring. In extreme cases, this malfunction can damage the torch (when the arc can be started but the electrode cannot move). In other failure modes, the nozzle may separate from the frame.
- thermal plastic can be overmolded on a stamped brass piece to provide geometric stability such that the aforementioned melting and warping does not occur.
- the sleeve material can be a metal alloy and can be used with or without a second metal coating.
- brass is used.
- Other metals that can be used include nickel-plated brass, copper, aluminum, steel, or other metals.
- Another benefit of overmolded plastic on a brass sleeve can be a decreased cost (e.g., $1.30 as compared with about $5 for Vespel). Such embodiments can reduce or eliminate local melting in the inner diameter and can provide a reliable starting performance and robust torch.
- FIG 3A is an isometric illustration of an inner cartridge assembly 300 for a plasma arc torch, according to an illustrative embodiment useful to understand the invention. Visible from the exterior are a shield 304 having vent holes 306 (e.g., holes 306A-D as shown), a nozzle body 308 having flow holes or inlet swirl holes 312 (e.g., holes 312A, 312B as shown in figure 3A ), a front insulator (or shield insulator) 314, and a rear insulator (or lock ring) 316.
- vent holes 306 e.g., holes 306A-D as shown
- nozzle body 308 having flow holes or inlet swirl holes 312 (e.g., holes 312A, 312B as shown in figure 3A )
- a front insulator (or shield insulator) 314, and a rear insulator (or lock ring) 316 are described more fully in conjunction with the cross-sectional view shown in Figure 3B below.
- FIG 3B is a cross-sectional illustration of the inner cartridge assembly 300 of Figure 3A , according to an illustrative embodiment useful to understand the invention.
- an electrode 320 having an emitting element 322, an arc constrictor or nozzle orifice 324, shield flow holes 328 (e.g., flow holes 328A-B as shown) directed toward the nozzle orifice 324, an insulator sleeve 332, and a cooling gas flow channel 336.
- the nozzle body 308 functions as the cartridge frame to which other parts attach.
- the nozzle body 308 can be made of aluminum, which can enhance heat conduction over previous materials and configurations as described above.
- the nozzle orifice 324 can be made of copper and can be pressed onto the nozzle body 308. In such embodiments, the nozzle body 308 can serve as a heat sink for the copper nozzle orifice 324.
- improved gas flow surfaces can assist in cooling, e.g., with shield gas flowing forward through holes 328A, 328B just outside of the press area.
- a press fit arrangement can also provide improved thermal conduction paths between torch parts as a result of tight tolerances between the surfaces of the parts.
- the press fit arrangement includes an interference fit and/or a tabbed or interlocking fit having one or more step-like features.
- the small size of the press fit design has the additional advantages of reducing manufacturing and/or material costs and simplifying manufacture and assembly of the components (e.g., by having fewer parts).
- the nozzle shield 304 can also be made of copper and can be pressed onto an anodized aluminum insulator 314 at a surface 305A. This assembly can then be pressed onto the nozzle body 308 at a press fit surface 305B. In such embodiments, the shield insulator 314 connects the nozzle body 308 to the shield 304. In some embodiments, the shield insulator 314 is press fit to the nozzle body 308. In some embodiments, the shield insulator 314 is an electrically insulative ring and/or includes a set of press-fit surfaces 305A, 305B that connect the shield 304 and the nozzle body 308.
- the shield insulator 314 can connect the nozzle body 308 to the shield 304 such that the nozzle body 308 and the shield 304 are electrically insulated from one another while still transferring thermal energy to one another.
- using a two-piece shield insulator can increase (e.g., double) electrical insulation abilities as a result of increasing contact surfaces.
- the nozzle shield 304 can be considerably smaller than previous shields, allowing for efficient manufacture and assembly of components, improved durability, and greater assurances of proper orientation of cartridge parts relative to one another.
- a prior art stock shield might have a diameter of about one inch (25.4 mm) and a mass of about 0.04 pounds (18.1 g)
- a cartridge shield in accordance with an embodiment can have a diameter of about 0.5 inches (12.7 mm) with a mass of less than 0.01 pounds (4.5 g) (e.g., about 0.007 pounds (3.2 g)).
- a prior art stock shield might have a diameter of about one inch (25.4 mm) with a mass of about 0.05 pounds (22.7 g), whereas a cartridge shield in accordance with an embodiment can have a diameter of about a half inch (12.7 mm) with a mass of about 0.01 pounds (4.5 g) (e.g., 0.013 pounds (5.9 g)).
- the smaller size configuration can carry significant advantages.
- the nozzle shield 304 is exposed to a cold gas entering the shield area, e.g., via shield flow holes 328, which can further reduce the temperature.
- the flow holes 328 can each have a total cross sectional area of at least about one square inch (645 mm 2 ).
- the electrode 320 includes a base made of copper. In some embodiments, the electrode 320 base has a small diameter with a pressed-on insulator sleeve 332 made of anodized aluminum and/or plastic used for electrical isolation. In some embodiments, a cooling gas flow channel or gap 336 exists between the insulator sleeve 332 and the nozzle body 308. In some embodiments, a cool gas flows in the gap 336. In some embodiments, a "dumbbell" configuration 340 defined by two end contacts 340A, 340B is used, which can reduce or minimize contact area between the nozzle body 308 and the insulator sleeve 332. Such a configuration can reduce friction between parts.
- the sleeve 332 contacts the electrode 320, which can be part of a separate current path from the nozzle body 308 and/or a different portion of the current path from the nozzle body 308.
- the electrode 320 and the nozzle body 308 can be electrically separated by a gap to create the arc and/or to ensure proper orientation of the parts in the torch.
- the nozzle 308 and the electrode 320 can be in physical contact between the sleeve 332 and the nozzle body 308.
- insulative layers are needed in this region so that current is able to pass through the emitting element 322.
- a wall of the nozzle body 342 near which the electrode 320 moves can stay comparatively cool during operation as gas flow passes both on the inside of the nozzle body 308 and directly across an exterior surface 344 of the nozzle 324.
- the material choice e.g., aluminum or another metal
- the material choice for the nozzle body 342 design provides for a better conduction path and heat sink ability as compared with previous materials such as Vespel TM . Such factors assist in cooling the electrode isolation piece and allow the electrode to function even after a deep pit is formed in the emitting element from electrode use.
- a lock ring 316 (or isolation ring) forms an interface 346 between the cartridge 300 and the torch.
- the lock ring 316 can be made of anodized aluminum.
- the lock ring 316 can be pressed into the nozzle body to "trap" the moveable electrode 320.
- the lock ring 316 can contain the components within the cartridge 300 and electrically isolate the torch.
- the lock ring 316 is replaced by heat shrinking or gluing.
- the lock ring 316 is shaped to orient the cartridge 300 (e.g., axially), to optimize gas flow, to enable electrical connection to the cathode, and/or to provide electrical isolation.
- the cartridges or consumable assemblies are about 3.5 inches (88.9mm) in length and 1.1 inches (27.9mm) in diameter.
- the retaining cap is considered part of the torch, e.g., not a consumable component.
- machining steps can be minimized, with no machining necessary after assembly (as compared to some torch assemblies that require a final machining step to achieve functional axiality of the cartridge).
- the reduction in swirl holes can minimize drilling operations compared to prior art swirl rings.
- replacing Vespel TM with aluminum can significantly reduce manufacturing costs of the cartridge.
- copper is used only in certain locations in the electrode, nozzle, and/or orifice, which can reduce manufacturing costs by reducing the use of this expensive material.
- copper can be concentrated primarily in an inner core or region. While copper can be desirable for its thermal and electrical properties, it is also more expensive than other materials, and so designs that minimize its usage are sought.
- Figures 4A-4B and 5 are cross-sectional illustrations of consumable cartridges for a plasma arc cutting system, each cartridge having a nozzle, an electrode, a swirl ring, a resilient element and an end cap.
- Figure 4A shows an exemplary cartridge design 400.
- the cartridge 400 includes a swirl ring 402, an end cap 406, a nozzle 408 and an electrode 404.
- the electrode 404 can be a spring-forward electrode for a contact start plasma arc torch, where a resilient element 412 (e.g., a spring) exerts a separating force on the distal end of the electrode 404 to bias the electrode 404 away from the end cap 406 and toward the nozzle 408.
- the resilient element 412 can also be a part of the cartridge 400.
- the cartridge 400 can include a starting mechanism for contact starting a plasma arc torch upon assembly into the torch.
- the swirl ring 402 can extend substantially over the length of the electrode 404 along a longitudinal axis 410 of the electrode 404.
- the swirl ring 402 is manufactured through injection molding of high-temperature thermoplastics (e.g., PAI, PEI, PTFE, PEEK, PEKPEKK, etc).
- thermoplastics e.g., PAI, PEI, PTFE, PEEK, PEKPEKK, etc.
- Use of thermoplastics to manufacture swirl rings can reduce cartridge cost in comparison to Vespel TM , which is a material that has been used to manufacture swirl rings, but is comparatively more expensive. It is known that thermoplastics have operating temperatures that are lower than Vespel TM (a thermoset), which can impact the integrity of swirl rings and electrode life.
- thermoplastics resins having various fortifying additives that provide the desired thermal resistance and/or thermal conductivity have resolved the high temperature performance issues, thus enabling the effective use of thermoplastics in these cartridges.
- thermoplastics have a sufficently high-temperature resistance and (2) a cartridge design that properly incorporates thermoplastics can avoid exposure of the thermoplastics to excessive temperatures during operation.
- end-of-life event which is also the end of life of the cartridge, the simultaneous melting of the plastic material is not problematic.
- the end cap 406 can be made of a conductive material, such as copper.
- the end cap 406 can be inexpensively formed via stamping from a material blank and can be irremoveably inserted, press fit or over molded onto the cartridge 400.
- the end cap 406 is configured to contain the resilient element 412 within the cartridge 400 and compress the resilient element 412 against the distal end of the electrode 404 such that the resilient element 412 exerts a separating force on the distal end of the electrode 404 to bias the electrode 404 toward the nozzle 408.
- end cap 406 may be shaped to matingly engage a patterned torch head and/or may include a set of fluid flow holes formed therethrough.
- an unreleasable snap-fit interface 414 is formed between the swirl ring 402 and the nozzle 408 to join the two consumable components together as a part of the cartridge 400.
- a second snap-fit interface 416 can be formed between the swirl ring 402 and the end cap 406 to join the two consumable components together as a part of the cartridge 400.
- the swirl ring 402 can be over-molded onto the end cap 406.
- the end cap 406 can also be capsulated by the swirl ring 402 and the resilient element 412 (e.g., a spring), where the end cap 406 can move within the cartridge 400.
- Figure 4B shows another exemplary cartridge design 450.
- the cartridge 450 includes a swirl ring 452, an end cap 456, a nozzle 458 and an electrode 454.
- the cartridge 450 also includes a resilient element 462 that functions similarly as the resilient element 412 of FIG. 4A .
- the cartridges of Figures 4A and 4B have different electrodes (e.g., different sizes of heat exchanger flanges, circumferential flange for uniform flow), different nozzles (e.g., different swirl ring attachment), and different swirl rings (e.g., different swirl holes and attachment).
- an interface 464 is formed as the swirl ring 452 is inserted into position in relation to the nozzle 458.
- Another interface 466 can be formed between the swirl ring 452 and the end cap 456.
- Figure 5 shows another exemplary cartridge design 500.
- the cartridge 500 includes a swirl ring 502, a sleeve 514, an end cap 506, a nozzle 508 and an electrode 504.
- the cartridge 500 also includes a resilient element 512 that functions similarly as the resilient element 512 of Figure 4A .
- the sleeve 514 and/or end cap 506 can be made from a conductive material (e.g., copper) using a stamping method.
- the sleeve 514 can be press fit or over molded onto the cartridge 500.
- the end cap 506 can be a part of the sleeve 514. Therefore, the sleeve 514 and the end cap 506 can be constructed as a single component piece.
- the swirl ring 502 can be relatively short in comparison to the swirl ring 402 such that the swirl ring 502 only extends along a portion of the length of the electrode 504 in the longitudinal axis 510.
- the swirl ring 502 can be manufactured through injection molding of high-temperature thermoplastics (e.g., Torlon TM ).
- a snap-fit interface 520 can be formed between the swirl ring 502 and the nozzle 508 to join the two consumable components together as a part of the cartridge 500.
- Another snap-fit interface 518 can be formed between the swirl ring 502 and the sleeve 514 to join the two consumable components together as a part of the cartridge 500.
- the swirl ring 502 can be over-molded onto the sleeve 514.
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Plasma Technology (AREA)
- Arc Welding In General (AREA)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP24159468.8A EP4351280A3 (en) | 2018-11-07 | 2019-11-07 | Frame for a cartridge for a plasma arc cutting system, method of cooling the plasma arc cutting system and method of manufacturing the frame |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201862756996P | 2018-11-07 | 2018-11-07 | |
PCT/US2019/060318 WO2020097365A1 (en) | 2018-11-07 | 2019-11-07 | Consumable cartridge for a plasma arc cutting system |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP24159468.8A Division EP4351280A3 (en) | 2018-11-07 | 2019-11-07 | Frame for a cartridge for a plasma arc cutting system, method of cooling the plasma arc cutting system and method of manufacturing the frame |
Publications (3)
Publication Number | Publication Date |
---|---|
EP3878244A1 EP3878244A1 (en) | 2021-09-15 |
EP3878244C0 EP3878244C0 (en) | 2024-02-28 |
EP3878244B1 true EP3878244B1 (en) | 2024-02-28 |
Family
ID=69165521
Family Applications (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19836670.0A Active EP3878244B1 (en) | 2018-11-07 | 2019-11-07 | Frame for a cartridge for a plasma arc cutting system, method of cooling the plasma arc cutting system and method of manufacturing the frame |
EP24159468.8A Pending EP4351280A3 (en) | 2018-11-07 | 2019-11-07 | Frame for a cartridge for a plasma arc cutting system, method of cooling the plasma arc cutting system and method of manufacturing the frame |
Family Applications After (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP24159468.8A Pending EP4351280A3 (en) | 2018-11-07 | 2019-11-07 | Frame for a cartridge for a plasma arc cutting system, method of cooling the plasma arc cutting system and method of manufacturing the frame |
Country Status (5)
Country | Link |
---|---|
EP (2) | EP3878244B1 (zh) |
JP (1) | JP7411646B2 (zh) |
CN (1) | CN112913335B (zh) |
MX (1) | MX2021003748A (zh) |
WO (1) | WO2020097365A1 (zh) |
Family Cites Families (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2578137B1 (fr) * | 1985-02-22 | 1987-03-27 | Soudure Autogene Francaise | Torche de soudage ou de coupage plasma munie d'une cartouche tuyere |
GB8615759D0 (en) * | 1986-06-27 | 1986-08-06 | W T C Holdings Ltd | Air plasma arc torch |
JPH03174980A (ja) * | 1989-09-25 | 1991-07-30 | Koike Sanso Kogyo Co Ltd | プラズマトーチ |
JPH07192892A (ja) * | 1993-12-24 | 1995-07-28 | Komatsu Ltd | プラズマトーチ |
JPH0963790A (ja) * | 1995-08-24 | 1997-03-07 | Koike Sanso Kogyo Co Ltd | プラズマトーチのノズル |
US5893985A (en) * | 1997-03-14 | 1999-04-13 | The Lincoln Electric Company | Plasma arc torch |
US8901451B2 (en) * | 2011-08-19 | 2014-12-02 | Illinois Tool Works Inc. | Plasma torch and moveable electrode |
US9480139B2 (en) * | 2013-07-18 | 2016-10-25 | Hypertherm, Inc. | Plasma ARC torch electrode with symmetrical plasma gas flow |
US10456855B2 (en) * | 2013-11-13 | 2019-10-29 | Hypertherm, Inc. | Consumable cartridge for a plasma arc cutting system |
US9981335B2 (en) * | 2013-11-13 | 2018-05-29 | Hypertherm, Inc. | Consumable cartridge for a plasma arc cutting system |
CN113275718B (zh) * | 2014-05-09 | 2024-02-23 | 海别得公司 | 用于等离子弧切割系统的可消耗筒 |
EP3334556B1 (en) * | 2015-08-12 | 2023-07-05 | Hypertherm, Inc. | Consumable cartridge for a plasma arc torch, method of assembling such consumable cartridge, and method of installing a consummable cartridge into a plasma arc torch |
CN106715027B (zh) * | 2014-08-12 | 2020-04-21 | 海别得公司 | 用于等离子弧焊炬的成本有效的筒 |
DE202015002334U1 (de) * | 2014-10-14 | 2015-06-17 | Hypertherm, Inc. | Verbrauchsteile mit hoher Zugänglichkeit für ein Plasmalichtbogenschneidsystem |
CA3049914A1 (en) * | 2017-02-09 | 2018-08-16 | Hypertherm, Inc. | Swirl ring and contact element for a plasma arc torch cartridge |
-
2019
- 2019-11-07 WO PCT/US2019/060318 patent/WO2020097365A1/en unknown
- 2019-11-07 JP JP2021518000A patent/JP7411646B2/ja active Active
- 2019-11-07 EP EP19836670.0A patent/EP3878244B1/en active Active
- 2019-11-07 MX MX2021003748A patent/MX2021003748A/es unknown
- 2019-11-07 CN CN201980072920.5A patent/CN112913335B/zh active Active
- 2019-11-07 EP EP24159468.8A patent/EP4351280A3/en active Pending
Also Published As
Publication number | Publication date |
---|---|
JP7411646B2 (ja) | 2024-01-11 |
EP3878244A1 (en) | 2021-09-15 |
JP2022504056A (ja) | 2022-01-13 |
EP3878244C0 (en) | 2024-02-28 |
CN112913335B (zh) | 2024-04-12 |
CN112913335A (zh) | 2021-06-04 |
EP4351280A2 (en) | 2024-04-10 |
MX2021003748A (es) | 2021-05-14 |
EP4351280A3 (en) | 2024-07-10 |
WO2020097365A1 (en) | 2020-05-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US11684994B2 (en) | Consumable cartridge for a plasma arc cutting system | |
AU2015255668B2 (en) | Consumable cartridge for a plasma arc cutting system | |
US11991813B2 (en) | Cost effective cartridge for a plasma arc torch | |
US20200023456A1 (en) | Consumable Cartridge for a Plasma Arc Cutting System | |
US11278983B2 (en) | Consumable cartridge for a plasma arc cutting system | |
EP3334556B1 (en) | Consumable cartridge for a plasma arc torch, method of assembling such consumable cartridge, and method of installing a consummable cartridge into a plasma arc torch | |
EP3878244B1 (en) | Frame for a cartridge for a plasma arc cutting system, method of cooling the plasma arc cutting system and method of manufacturing the frame | |
US20240109147A1 (en) | Consumable cartridge for a plasma arc cutting system | |
EP3141090B1 (en) | Replaceable consumable cartridge for a plasma arc cutting system | |
US11432393B2 (en) | Cost effective cartridge for a plasma arc torch |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: UNKNOWN |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE |
|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
17P | Request for examination filed |
Effective date: 20210423 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
DAV | Request for validation of the european patent (deleted) | ||
DAX | Request for extension of the european patent (deleted) | ||
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
INTG | Intention to grant announced |
Effective date: 20230420 |
|
GRAJ | Information related to disapproval of communication of intention to grant by the applicant or resumption of examination proceedings by the epo deleted |
Free format text: ORIGINAL CODE: EPIDOSDIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: GRANT OF PATENT IS INTENDED |
|
INTC | Intention to grant announced (deleted) | ||
INTG | Intention to grant announced |
Effective date: 20230914 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE PATENT HAS BEEN GRANTED |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 602019047463 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
U01 | Request for unitary effect filed |
Effective date: 20240327 |
|
U07 | Unitary effect registered |
Designated state(s): AT BE BG DE DK EE FI FR IT LT LU LV MT NL PT SE SI Effective date: 20240409 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240628 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240529 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: HR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240228 Ref country code: RS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240528 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: ES Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240228 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: RS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240528 Ref country code: NO Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240528 Ref country code: IS Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240628 Ref country code: HR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240228 Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240529 Ref country code: ES Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240228 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: PL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240228 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: PL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240228 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SM Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240228 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20240228 |