Jacket for a liquid cooled plasma arc torch cartridge

Abstract

A shroud for a liquid-cooled plasma torch is provided, the shroud comprising: a substantially hollow body having a proximal end and a distal end; a shroud outlet orifice centrally located at the distal end of the hollow body; a retaining feature disposed at the proximal end of the hollow body; a circumferential liquid cooling channel disposed in an outer surface of the body, the liquid cooling channel being configured to circulate a liquid coolant flow around the outer surface; and at least one orifice disposed at the proximal end of the hollow body, the at least one orifice being configured to guide a protective gas flow passing through it toward the shroud outlet orifice. A method for operating the shroud for the liquid-cooled plasma torch is also provided.

Description

[0001] This application is a divisional application of the patent application filed on July 8, 2021, with application number 202180047900.X and invention title "Jacket for a Cylinder of a Liquid-Cooled Plasma Arc Torch".

[0002] Cross-references to related applications This application claims the benefit and priority of U.S. Provisional Patent Application No. 63 / 049,408, filed July 8, 2020, the entire contents of which are the property of the assignee of this application and are incorporated herein by reference in their entirety. Technical Field

[0003] The present invention generally relates to a jacket for a consumable cartridge for a liquid-cooled plasma arc torch, wherein the cartridge has multiple integrated components. Background Technology

[0004] Plasma arc torches, such as thermal processing torches, are widely used for high-temperature processing of materials (e.g., heating, cutting, gouging, and marking). A plasma arc torch generally comprises a torch head, an electrode mounted within the torch head, a firing insert disposed within the inner bore of the electrode, a nozzle mounted within the torch head with a central outlet orifice, a shroud, electrical connections, a cooling passage, a passage for the arc control fluid (e.g., plasma gas), and a power supply device. A vortex ring is used to control the fluid flow pattern within the plasma chamber formed between the electrode and the nozzle. In some torches, a retaining cap is used to hold the nozzle and / or vortex ring within the plasma arc torch. During operation, the torch generates a plasma arc, which is a contracting jet of ionized gas with high temperature and sufficient momentum to aid in the removal of molten metal. The gas used in the torch can be non-reactive (e.g., argon or nitrogen) or reactive (e.g., oxygen or air).

[0005] Existing plasma cutting systems comprise large arrays of individual consumables (e.g., six different consumables) available for different currents and / or operating modes, which are repeatedly assembled and disassembled by the user in the field to perform thermal processing operations. This large number of consumable options requires the user to have a large number of parts and inventory, and can cause user confusion and increase the likelihood of incorrect consumable installation. For example, these consumables typically have different expected lives and different part numbers, which end users may easily confuse, leading to poor cut quality or damage to the workpiece and / or torch parts. A large number of consumable options can also result in long torch setup times and make it difficult to switch between cutting processes requiring different arrangements of consumables in the torch, which is typically used one part at a time in the field. For example, special tools are often required to install and remove at least one of the electrodes or nozzles from the torch for maintenance and replacement purposes. Therefore, selecting and installing the correct set of consumables for a specific cutting task prior to a cutting operation can be cumbersome and time-consuming. Furthermore, the selection, assembly, and installation of these parts in the field when older parts are used with newer parts can lead to alignment or compatibility issues. During torch operation, existing consumables may encounter performance issues, such as the inability to maintain correct consumable alignment and spacing. Because each consumable requires individual alignment, existing plasma arc torches and consumables are machined with relatively tight tolerances to ensure proper alignment.

[0006] What is needed is a new and improved consumable platform for liquid-cooled plasma torches that reduces the number of parts, improves system performance (e.g., part alignment, cut quality, consumable life, variability / versatility, etc.), and simplifies the installation and use of consumables by the end user. Summary of the Invention

[0007] This invention provides one or more integrated, cost-effective cartridge designs for liquid-cooled plasma torches. Typically, because the cartridge comprises a set of two or more consumable parts, it offers ease of use and reduces installation time compared to installing / replacing each consumable part individually in a conventional plasma torch. Using a consumable cartridge also reduces the likelihood of operators inserting incorrect consumable parts, contaminating parts during installation, and / or accidentally placing fragile or faulty parts back onto the torch. These advantages eliminate the need for experienced operators to operate the final liquid-cooled plasma torch. Furthermore, using a cartridge in a liquid-cooled torch improves part alignment, cut consistency, and cut quality. Additionally, using a consumable cartridge enhances the supplier experience by requiring less inventory and storage of consumables.

[0008] In one aspect, the invention features a jacketed consumable cartridge for a liquid-cooled plasma torch. The jacketed consumable cartridge includes: an electrode; a vortex ring securely attached to and circumferentially disposed around the distal end of the electrode; and a nozzle securely attached to the vortex ring, circumferentially disposed around the distal end of the electrode, wherein a portion of the vortex ring is located between the electrode and the nozzle. The jacketed consumable cartridge further includes a sleeve securely attached to and circumferentially disposed around the distal end of the nozzle and a shroud securely attached to and circumferentially disposed around the distal end of the sleeve. The proximal end of the sleeve is adapted to (i) extend axially through the proximal end of the shroud and (ii) extend radially beyond the radial extent of the shroud.

[0009] In some embodiments, the eddy current ring is securely attached to the electrode via two distinct circumferential interfaces on the inner surface of the eddy current ring. In some embodiments, the collet is securely attached to the nozzle via at least two distinct circumferential interfaces on the outer surface of the nozzle. In some embodiments, the shroud is securely attached to the collet via a retaining feature circumferentially disposed around the outer surface of the collet. The retaining feature is configured to receive the proximal end of the shroud for secure attachment.

[0010] In some embodiments, the nozzle is securely attached to the vortex ring via two distinct circumferential interfaces on the outer surface of the vortex ring. The vortex ring may include a plurality of slots formed on the outer surface and circumferentially distributed around the vortex ring. The plurality of slots are shaped to complement the internal profile of the nozzle to define a set of gas vortex paths. In some embodiments, each of the plurality of slots is angled.

[0011] In some embodiments, at least one of the vortex ring or the sleeve is made of an injection-molded plastic material. In some embodiments, the sleeve is circumferentially disposed between the nozzle and the shroud to physically separate and electrically isolate the nozzle and the shroud.

[0012] In some embodiments, the proximal end of the sleeve is shaped to flexibly engage the torch body of the plasma torch to form a substantially fluid-impermeable seal, thereby enabling the delivery of both liquid and gas from the torch body to the sleeve. In some embodiments, the sleeve includes a plurality of orifices circumferentially disposed around the proximal end, each orifice connecting an inner surface of the sleeve to an outer surface, configured to meter gas and guide gas from the torch body to the shroud. In some embodiments, the sleeve includes a plurality of axial channels disposed in the inner surface of the sleeve and circumferentially distributed around the sleeve, the plurality of axial channels being configured to complement the outer profile of the nozzle to define corresponding passages in a coolant pathway for delivering liquid between the nozzle and the sleeve.

[0013] In some embodiments, the nozzle includes an alignment surface on the outer circumference of the nozzle's proximal end, the alignment surface being configured to allow the cylinder to be aligned with the torch body of the plasma arc torch when engaged between the cylinder and the torch body. In some embodiments, the electrode includes a silver end disposed at the distal end of the electrode. In some embodiments, the shroud includes a plurality of orifices circumferentially disposed around the proximal end of the shroud, each orifice being shaped to guide, meter, and swirl a gas flow traveling through the orifice toward an outlet orifice of the shroud.

[0014] In some embodiments, the ratio of the length to the width of the consumable cartridge is less than about 1.25.

[0015] In another aspect, a jacket is provided for a consumable cartridge for a liquid-cooled plasma torch. The consumable cartridge, including an electrode, a nozzle, and a shroud, is configured to be removably attached to the torch body of the plasma torch. The jacket includes a substantially electrically insulated hollow body defining a longitudinal axis extending through the hollow body. The jacket also includes a distal end of the hollow body disposed along the longitudinal axis. The distal end is configured to (i) matingly engage a nozzle at an inner surface of the hollow body, and (ii) extend into a proximal end of the shroud to matingly engage the shroud at an outer surface of the hollow body. The jacket also includes a proximal end of the hollow body disposed along the longitudinal axis opposite to the distal end. The proximal end extends axially through the proximal end of the shroud and extends radially beyond the radial extent of the shroud. The proximal end is configured to matingly engage the torch body.

[0016] In some embodiments, the jacket further includes a plurality of orifices circumferentially disposed around the proximal end of the hollow body. Each orifice connects an inner surface of the hollow body to an outer surface of the hollow body and is configured to meter and guide gas flow from the torch body to the shroud. In some embodiments, the size of the plurality of orifices is configured to support a first operating current requirement of the consumable cartridge. This size differs from the size of a second plurality of orifices in a second jacket for a second consumable cartridge, which is configured to support an operating current requirement different from the first operating current requirement of the consumable cartridge.

[0017] In some embodiments, the jacket further includes a plurality of axial channels disposed in the inner surface of the hollow body and circumferentially distributed around the hollow body. In some embodiments, the plurality of channels are configured to complement the outer profile of the nozzle to define corresponding liquid coolant passages between the nozzle and the jacket. In some embodiments, the proximal end of the hollow body includes a circumferential coolant channel that is proximal to and in fluid communication with the plurality of axial channels to deliver a coolant flow between the torch body and the nozzle via the plurality of axial channels.

[0018] In some embodiments, the jacket further includes a retaining feature circumferentially disposed around the outer surface of the jacket at its distal end. The retaining feature is configured to receive the proximal end of the shield and lockably engage the shield to the hollow body. In some embodiments, the jacket further includes a plurality of inner alignment surfaces circumferentially disposed on the inner surface of the jacket. The plurality of inner alignment surfaces are configured to align the nozzle axially and radially relative to the jacket. In some embodiments, the jacket further includes an outer alignment surface circumferentially disposed on the outer surface of the jacket. The outer alignment surface is configured to align the shield axially and radially relative to the nozzle via the jacket.

[0019] In some embodiments, the hollow body of the jacket is made of an injection-molded plastic material. In some embodiments, the axial length of the hollow body is greater than the axial length of at least one of the nozzle, shroud, or electrode of the cylinder. In some embodiments, the ratio of the length of the jacket to the width of its proximal end is between about 0.7 and about 0.85, and the ratio of the length of the jacket to the width of its distal end is between about 1.4 and about 1.6.

[0020] In another aspect, in a consumable cartridge of a liquid-cooled plasma torch, wherein the consumable cartridge is configured for attachment to the torch body of the plasma torch, and the consumable cartridge includes a nozzle, a cartridge jacket, and a shroud, an improvement comprising a plurality of orifices circumferentially disposed around the proximal end of a hollow body surrounding the shroud. The plurality of orifices connect the inner surface of the hollow body to the outer surface of the hollow body. Each orifice is sized and shaped to guide, meter, and swirl a gas flow through the orifice toward an outlet orifice of the shroud.

[0021] In some embodiments, the consumable cartridge further includes a retaining feature circumferentially disposed around the inner surface of the shroud at the proximal end. The retaining feature is configured to complement a corresponding retaining feature of the cartridge sleeve to securely engage the shroud to the cartridge sleeve.

[0022] In some embodiments, a portion of the outer surface of the hollow body of the shield is adapted to come into contact with a liquid coolant fluid used to cool the shield.

[0023] In some embodiments, each of the plurality of orifices is angled to impart a tangential velocity to the gas flowing through the orifice.

[0024] In another aspect, a method for assembling a consumable cartridge for a liquid-cooled plasma torch. The method includes: securely attaching a vortex ring to a distal end of an electrode such that the vortex ring is circumferentially disposed around the distal end of the electrode; and securely attaching a nozzle to the vortex ring such that the nozzle is circumferentially disposed around the distal end of the electrode, wherein a portion of the vortex ring is located between the electrode and the nozzle. The method further includes: securely attaching a cartridge sleeve to the distal end of the nozzle such that the cartridge sleeve is circumferentially disposed around the distal end of the nozzle. The method further includes: securely attaching a shroud to the distal end of the cartridge sleeve such that the shroud is circumferentially disposed around the cartridge sleeve, wherein a proximal end of the cartridge sleeve extends axially through the proximal end of the shroud and extends radially beyond the radial extent of the shroud.

[0025] In some embodiments, the shroud is aligned axially and radially relative to the nozzle via a collet. In some embodiments, the collet electrically isolates the shroud and the nozzle. The collet may be made of an injection-molded plastic material.

[0026] In some embodiments, a plurality of axial cooling passages are formed in the cylinder. The plurality of cooling passages are defined by (i) respective channels in a plurality of axial channels disposed in the inner surface of the cylinder and distributed circumferentially around the cylinder and (ii) complementary outer surfaces of nozzles.

[0027] In some embodiments, the sleeve includes a radially extending proximal end comprising a plurality of orifices circumferentially disposed around the proximal end. Each orifice is configured to meter a gas flow and guide it from the torch body to the shroud.

[0028] In some embodiments, the silver tip is positioned at the distal end of the electrode. In some embodiments, the ratio of the length of the consumable cartridge to the width of the jacket is less than about 1.25. In some embodiments, the consumable cartridge is attached to the torch body of the plasma arc torch. The nozzle of the consumable cartridge is adapted to be aligned axially and radially with respect to the torch body.

[0029] In another aspect, a method is provided for delivering at least one of a gas or a liquid in a liquid-cooled plasma torch, the liquid-cooled plasma torch including a consumable cartridge and a torch body. The method includes attaching the consumable cartridge to the torch body. The consumable cartridge includes an electrode, a nozzle circumferentially disposed around and securely attached to the electrode, a sleeve circumferentially disposed around and securely attached to the nozzle, and a shroud circumferentially disposed around and securely attached to the sleeve. The method further includes delivering gas from the torch body to a plurality of orifices circumferentially disposed around a proximal tip of the sleeve. The method further includes metering the gas through the plurality of orifices and guiding it from an inner surface of the sleeve to an outer surface of the sleeve to deliver gas on the outer surface of the shroud.

[0030] In some embodiments, the method further includes: metering the gas through a plurality of orifices circumferentially disposed around the proximal tip of the shield and guiding it from the outer surface of the shield to the inner surface of the shield; imparting a vortex pattern to the gas flow through the orifices through the plurality of orifices disposed in the shield; and discharging the gas from the plasma torch through an outlet orifice of the shield.

[0031] In some embodiments, the method further includes circulating liquid between the cylinder and the torch body to cool the plasma torch. Circulating the liquid includes delivering liquid from at least one orifice in the torch body to one or more of a plurality of axial cooling passages defined by (i) a respective channel of a plurality of axial channels disposed in the inner surface of the cylinder jacket and circumferentially distributed around the cylinder jacket, and (i) the outer surface of the nozzle. Circulating the liquid further includes conducting liquid on the outer surface of the nozzle from the proximal tip of the nozzle to the distal tip of the nozzle through one or more cooling passages to cool the nozzle. Circulating the liquid further includes: circulating liquid around the distal tip of the nozzle; and directing at least a portion of the liquid to a shroud to cool the shroud. In some embodiments, said at least a portion of the liquid is directed to cool the outer surface of the shroud.

[0032] In some embodiments, the method further includes forming a seal between the proximal tip of the torch body and the cartridge jacket, the seal being substantially fluid-impermeable to allow both liquid and gas to be delivered from the torch body to the cartridge. The seal establishes a flexible engagement between the proximal tip of the torch body and the cartridge jacket.

[0033] In another aspect, a method is provided for mounting a desired consumable cartridge in a liquid-cooled plasma torch. The method includes providing a first consumable cartridge including a first cartridge jacket configured to axially and radially align a first nozzle relative to a first shroud within the first consumable cartridge. The first cartridge jacket is configured to support a first operating current requirement of the first consumable cartridge. The method further includes providing a second consumable cartridge including a second cartridge jacket configured to axially and radially align a second nozzle relative to a second shroud within the second consumable cartridge. The second cartridge jacket is configured to support a second operating current requirement of the second consumable cartridge, different from the first operating current. The method further includes: selecting one of the first or second consumable cartridges by comparing a desired operating current with first and second operating current requirements associated with corresponding first and second consumable cartridges; and mounting the selected consumable cartridge to the torch body of the plasma torch.

[0034] In some embodiments, a first sleeve includes a first plurality of orifices configured to meter and guide a protective gas flow, and a second sleeve includes a second plurality of orifices configured to meter and guide a protective gas flow. In some embodiments, a first diameter of each of the first plurality of orifices differs from a second diameter of each of the second plurality of orifices. Each of the first and second diameters is sized according to a corresponding one of different operating current requirements.

[0035] In some embodiments, a first sleeve has a first axial length configured to cover one or more of a plurality of protective gas orifices in the torch body, and a second sleeve has a second axial length configured to cover one or more of the plurality of protective gas orifices in the torch body. In some embodiments, the first axial length differs from the second axial length to cover different numbers of the plurality of protective gas orifices in the torch body, thereby achieving different operating current requirements.

[0036] In some embodiments, the nozzle of the selected consumable cartridge is configured to align the selected consumable cartridge axially and radially relative to the torch body.

[0037] In some embodiments, the shroud of the selected consumable cartridge includes a plurality of protective gas orifices circumferentially disposed around the proximal end of the shroud. Each protective gas orifice is shaped to guide, meter, and swirl a flow of protective gas traveling through the orifice toward an outlet orifice in the shroud. In some embodiments, the diameter of the protective gas orifices is designed to support the operating current requirements associated with the selected consumable cartridge. Attached Figure Description

[0038] The advantages and further advantages of the invention described above can be better understood by referring to the following description in conjunction with the accompanying drawings. The drawings are not necessarily drawn to scale; rather, the focus is generally on illustrating the principles of the invention.

[0039] Figure 1 An exploded view of a liquid-cooled plasma arc torch according to some embodiments of the present invention is shown, the torch generally comprising a torch body and a cylinder.

[0040] Figure 2 Some embodiments according to the present invention are shown. Figure 1 A cross-sectional view of a portion of an assembled plasma torch, including the cylinder.

[0041] Figure 3a and Figure 3b Some embodiments according to the present invention are shown respectively. Figure 2 Cross-sectional profile and external profile of an exemplary construction of a cylinder.

[0042] Figure 4a and Figure 4bSome embodiments according to the present invention are shown respectively. Figure 2 Cross-sectional and external profile views of an exemplary construction of the sleeve of the cylinder.

[0043] Figure 5 Some embodiments according to the present invention are shown. Figure 2 An external profile diagram of an exemplary configuration of the nozzle of the cylinder.

[0044] Figure 6a and Figure 6b Some embodiments according to the present invention are shown. Figure 2 External profile and cross-sectional profile of an exemplary construction of a vortex ring of a cylinder.

[0045] Figure 7 Some embodiments according to the present invention are shown. Figure 2 A cross-sectional profile of an exemplary configuration of the electrode of the cylinder.

[0046] Figure 8 Some embodiments according to the present invention are shown. Figure 2 The external outline of the protective cover of the cylinder.

[0047] Figure 9 Some embodiments according to the present invention are shown. Figure 2 A cross-sectional view of a plasma arc torch, oriented in an exemplary protective gas flow path from the torch body to the torch cylinder.

[0048] Figure 10 Some embodiments according to the present invention are shown. Figure 2 A cross-sectional view of a plasma arc torch, oriented to an exemplary liquid coolant flow path that circulates between the torch body and the torch barrel.

[0049] Figure 11a and Figure 11b A cross-sectional profile view of another exemplary plasma torch with different configurations to provide a variable protective gas flow rate, according to some embodiments of the present invention, is shown.

[0050] Figure 12 Some embodiments according to the present invention are shown. Figure 11a and Figure 11b A set of exemplary performance results for different configurations of plasma torches.

[0051] Figure 13 The illustrations depict assembly according to some embodiments of the present invention. Figure 2 An exemplary process for a consumable jacketed sleeve of a liquid-cooled plasma torch.

[0052] Figure 14The illustration depicts an exemplary process for selecting and installing a desired consumable cartridge for a plasma torch according to some embodiments of the present invention. Detailed Implementation

[0053] This invention provides a liquid-cooled plasma arc torch comprising a liquid-cooled consumable cartridge for removable attachment to the torch body. In some embodiments, the consumable cartridge is an integral component, wherein components of the cartridge are not individually repairable or disposable. Therefore, if a component of the consumable cartridge needs replacement, the entire cartridge is replaced. In some embodiments, the consumable cartridge has a single-part identifier. In some embodiments, the consumable cartridge is a "single-use" cartridge, wherein the cartridge is replaced by the operator after any component of the cartridge reaches the end of its service life, rather than repairing and replacing individual consumables as in conventional torch designs. In some embodiments, the cartridge is replaced after a single operational phase that may involve multiple arcs. In some embodiments, the cartridge is replaced after a single arc event.

[0054] Figure 1 An exploded view of a liquid-cooled plasma torch 10 according to some embodiments of the present invention is shown. The torch 10 generally includes a torch body 102 and a cylinder 104. The cylinder 104, including a plurality of consumable torch components, has a proximal end (region) 14 and a distal end (region) 16 along the central longitudinal axis A of the plasma torch 10. The torch body 102 has a proximal end (region) 20 and a distal end (region) 22 along the longitudinal axis A. Hereinafter, the proximal end of a component defines a region of a component that is away from the workpiece along the longitudinal axis A when the torch 10 is used to process a workpiece, and the distal end of a component defines a region of a component that is opposite to the proximal end and closer to the workpiece when the torch 10 is used to process a workpiece.

[0055] In some embodiments, the proximal end 14 of the cylinder 104 is matingly and removably engaged to and / or disengaged from the distal end 22 of the torch body 102 without the use of tools. For example, tool-free engagement between the torch body 102 and the cylinder 104 may include inserting the central coolant tube 116 of the torch body 102 into the electrode (not shown) of the cylinder 104 and engaging the proximal end 14 of the cylinder 104 to the distal end 22 of the torch body 102 via a push motion, threaded connection, interference fit, snap-fit, quick-lock, etc. Subsequently, an outer cap 120 may be disposed on the combination of the cylinder 104 and the torch body 102 to hold them in their engaged position. For example, the outer cap 120 may be screwed onto the torch body 102 from the cylinder 104. In some embodiments, the outer cap 120 includes a housing 120a (e.g., made of a conductive material such as brass) and an inner lining 120b (e.g., made of an electrically insulating material such as plastic). Figure 1As shown, the number of components and part numbers for the plasma torch 10 has been reduced, which facilitates the installation / removal of torch consumables by the end user and reduces the possibility of incorrect torch setup.

[0056] Figure 2 Some embodiments according to the present invention are shown. Figure 1 A cross-sectional view of a portion of the assembled plasma torch 10, including the cylinder 104. As shown in the figure, Figure 1 Interface 106 defines the boundary between the cylinder 104 and the torch head 102 after they are engaged with each other. The cylinder 104 is a substantially monolithic element comprising an electrode 108 (i.e., an arc emitter), a nozzle 110 (i.e., an arc retractor), a jacket 112, and a shroud 114, all concentrically arranged around a central longitudinal axis A. In some embodiments, the cylinder 104 further includes a vortex ring 150 arranged around the longitudinal axis A. Details regarding the cylinder 104 will be provided below. Figure 3a and Figure 3b Describe it. In such a case... Figure 2 In the engagement position between the torch body 102 and the cylinder 104 shown, the outer cap 120 may be disposed on a portion of the cover 114 of the cylinder 104 and screwed into the distal end 22 of the torch body 102 to hold the cylinder 104 against the torch body 102.

[0057] The torch body 102 includes a torch insulator 118, which may be made of an electrically insulating material such as plastic. The torch insulator 118 may be coupled to multiple components of the torch body 102, including a cathode 170 and a torch connector 124. For example, the torch insulator 118 may define a central channel in which the cathode 170 is disposed and coupled. When engaged between the torch body 102 and the cylinder 104, the distal end of the cathode 170 is configured to be electrically and / or physically coupled to the proximal end of the electrode 108 of the cylinder 104 to form a housing for enclosing the coolant tube 116 of the torch body 102. In some embodiments, the distal end of the torch insulator 118 is configured to be coupled to the torch connector 124. As shown, the torch connector 124 defines a plurality of orifices 126 circumferentially disposed in the outer surface of the connector 124 for metering the flow of protective gas from the torch body 102 to the cylinder 104 during engagement. Each orifice 126 may be oriented substantially perpendicular to the longitudinal axis A. In some embodiments, the torch connector 124 further defines a plurality of axial channels 128 circumferentially distributed within the body of the connector 124 for circulating a flow of liquid coolant between the torch body 102 and the cylinder 104 during engagement. Each axial channel 128 may be oriented substantially parallel to the longitudinal axis A. Figure 1As shown, the axial channels 128 can be divided into two groups, wherein one or more axial channels 128 of a first group 178 are located on one side of the torch body 102, and one or more axial channels 128 of a second group 182 are located on a substantially opposite side, the second group 182 being radially offset by approximately 180 degrees relative to the first group 178. Each group of axial channels 128 is adapted to deliver a coolant flow into or away from the torch body 102. Each axial channel 128 may have a distal opening 128b on the distal end face of the connector 124.

[0058] Figure 3a and Figure 3b Some embodiments according to the present invention are shown respectively. Figure 2 Cross-sectional and external profile views of an exemplary configuration of the cylinder 104 are provided. As described above, the cylinder 104 may generally include an electrode 108, a nozzle 110, a jacket 112, a shield 114, and a vortex ring 150, all concentrically arranged around the longitudinal axis A of the plasma torch 10. Generally, the various components of the cylinder may be directly or indirectly fixed to the cylinder jacket 112 while achieving axial and radial alignment (i.e., centering) relative to the central longitudinal axis A.

[0059] In some embodiments, the outer diameter of electrode 108 is inserted through the inner diameter of vortex ring 150. In this position, vortex ring 150 is matingly and securely attached to and circumferentially disposed around the outer surface of the distal end of electrode 108. More specifically, electrode 108 includes an external retaining feature 366 (e.g., one or more stepped portions of varying diameter of electrode 108) on its outer surface, which is configured to securely engage an internal retaining feature 368 (e.g., one or more complementary stepped portions or protrusions) on the inner surface of vortex ring 150 to prevent axial movement of electrode 108 and vortex ring 150 relative to each other and to radially align / center the components relative to each other. In some embodiments, a secure attachment between vortex ring 150 and electrode 108 is achieved only when nozzle 110 is circumferentially disposed on vortex ring 150, thereby applying external pressure to the engagement between vortex ring 150 and electrode 108. The matching between electrode 108 and eddy ring 150 can result in two different circumferential interfaces 390, 392 (i.e., alignment surfaces) between the inner surface of eddy ring 150 and the outer surface of electrode 108.

[0060] In some embodiments, the outer diameter of the vortex ring 150 is matched and securely attached to the inner diameter of the nozzle 110. As shown, the nozzle 110 may be circumferentially disposed around the distal end of the electrode 108, with at least a portion of the vortex ring 150 located between the nozzle 110 and the electrode 108. More specifically, the vortex ring 150 may be secured to the nozzle 110 by mating at least one retaining feature 352 (e.g., a stepped portion of the vortex ring 150 with varying diameter) on the outer surface of the vortex ring 150 with an internal retaining feature 358 (e.g., a complementary stepped portion or protrusion of the nozzle 110) on the inner surface of the nozzle 110 to prevent axial movement of the vortex ring 150 and the nozzle 110 relative to each other and to radially align / center the components relative to each other. In some embodiments, the mating between the vortex ring 150 and the nozzle 110 results in two distinct circumferential interfaces 394, 396 (i.e., alignment surfaces) between the outer surface of the vortex ring 150 and the inner surface of the nozzle 110.

[0061] In some embodiments, the outer diameter of the nozzle 110 is matched and securely attached to the inner diameter of the collet 112. As shown, the collet 112 is securely attached to the distal end of the nozzle 110 and is circumferentially disposed around the distal end of the nozzle 110, and the nozzle 110 in turn securely attaches the vortex ring 150 and the electrode 108 to the collet 112. The nozzle 110 is secured to the collet 112 by matching and securely engaging one or more external retaining features 370 on the outer surface of the nozzle 110 (e.g., one or more steps of the nozzle 110 with varying diameter) with one or more internal retaining features 372 on the inner surface of the collet 112 (one or more complementary steps or protrusions of the collet 112) to prevent axial movement of the nozzle 110 and the collet 112 relative to each other and to ensure that the components are radially aligned / centered relative to each other. In some embodiments, retaining feature 370 may further include a seal (e.g., an O-ring seal) 130 located between the inner surface of the distal end of the jacket 112 and the corresponding outer surface of the nozzle 110. Seal 130 is configured to further attach the jacket 112 to the nozzle 110 and provides the additional function of preventing leakage of liquid coolant between the two components. Matching between retaining features 370, 372 can result in three distinct circumferential interfaces 388, 398, 399 (i.e., alignment surfaces) between the outer surface of the nozzle 110 and the inner surface of the jacket 112.

[0062] In some embodiments, the outer diameter of the collet 112 is matched and securely attached to the inner diameter of the shroud 114. As shown, the shroud 114 is circumferentially disposed around the distal end of the collet 112. More specifically, an external retaining feature 362 (e.g., a stepped portion of the collet 112 with a diameter variation) on the outer surface of the collet 112 is securely attached / engaged to an internal retaining feature 364 (e.g., a complementary stepped portion or protrusion of the shroud 114) on the inner surface of the shroud 114 to prevent axial movement of the collet 112 and the shroud 114 relative to each other and to ensure that the components are radially aligned / centered relative to each other. For example, the retaining feature 362 on the collet 112 may include a notch circumferentially disposed around the outer surface, the notch being configured to receive a protrusion 364 at the distal end of the shroud 114. The matching between retaining features 362, 364 can result in at least one circumferential interface 384 (i.e., alignment surface) between the outer surface of the jacket 112 and the inner surface of the shield 114.

[0063] In some embodiments, the aforementioned retaining features 366, 368, 352, 358, 370, 372, 362, and 364 may engage with their corresponding retaining features via one of the following methods: snap-fit, press-fit, interference fit, crimping, friction fit, gluing, bonding, or welding. In some embodiments, the retaining features include one or more sealing O-rings or washers, for example, made of cured epoxy resin or rubber. In some embodiments, the secure attachment / engagement of the various components of the cylinder 104 is permanent throughout the service life of the cylinder 104 to prevent individual components of the cylinder 104 from being independently replaceable or repairable. For example, permanent attachment / engagement of components in the cylinder 104 may (i) make the cylinder 104 non-removable and / or (ii) cause permanent damage to individual components upon disassembly.

[0064] like Figure 3a As shown, during the final assembly and fastening of consumable components within the cylinder 104, the proximal end of the cylinder jacket 112 is adapted to extend axially along the longitudinal axis A in the proximal direction past the proximal end of the shroud 114. The proximal end of the electrode 108 is adapted to extend axially along the longitudinal axis A in the proximal direction past the proximal end of the jacket 112. Radially, the proximal end of the cylinder jacket 112 is adapted to extend beyond the maximum radial range 386 of the shroud 114. In some embodiments, the axial length of the cylinder jacket 112 is greater than the axial length of at least one of the nozzle 110, the shroud 114, or the electrode 108. In some embodiments, the ratio of the axial length of the cylinder 104 (i.e., from the proximal end of the electrode 108 to the distal end of the shroud 114) to the radial width of the cylinder 104 (i.e., the outer diameter of the jacket 112) is less than about 1.25.

[0065] Figure 4a and Figure 4b Some embodiments according to the present invention are shown respectively. Figure 2Cross-sectional and external profile views of an exemplary configuration of the sleeve 112 of the tube 102. The sleeve 112 includes an electrically insulating hollow body through which the longitudinal axis A of the plasma torch 10 extends. For example, the sleeve 112 may be made of a non-conductive injection-molded plastic material. In some embodiments, the material is Radel, a tough, injection-molded high-performance material. Therefore, injection molding technology can be used to manufacture the sleeve 112. In some embodiments, because the sleeve 112 is concentrically disposed between the nozzle 110 and the shroud 114, as referenced above... Figure 3a and Figure 3b Therefore, the jacket 112 is adapted to provide physical separation and electrical isolation between the nozzle 110 and the shroud 114.

[0066] As shown, the sleeve 112 generally includes a distal end 402 and a proximal end 404 along the longitudinal axis A of the plasma torch 10. Both the distal end 402 and the proximal end 404 may be substantially hollow and truncated conical in shape, wherein the radial extent (e.g., outer diameter) 406 of the hollow body of the proximal end 404 is greater than the radial extent (e.g., outer diameter) 408 of the hollow body of the distal end 402. In some embodiments, the ratio of the axial length of the sleeve 112 to the radial extent 406 of the proximal end 404 is about 0.7. In some embodiments, the ratio of the axial length of the sleeve 112 to the radial extent 408 of the distal end 402 is between about 1.4 and about 1.6, depending on the operating current (e.g., between about 260 amperes and about 80 amperes, respectively). Furthermore, the proximal end 404 of the sleeve 112 may be defined by a circumferential body portion 404a and a stepped / inclined inner wall portion 404b, the stepped / inclined inner wall portion 404b bridging the transition between the wider proximal end 404 and the narrower distal end 402 of the sleeve 112.

[0067] In some embodiments, regarding the engagement and alignment of the shroud and nozzle, at least a portion of the distal end 402 of the sleeve 112 is configured to extend into the proximal end of the shroud 114 to matingly and securely engage the shroud 114 on the circumferentially outer alignment interface / surface 384 via an outer retaining feature 364. The outer circumferential alignment interface 384 of the sleeve 112 is adapted to provide both axial and radial alignment of the shroud 114 relative to the sleeve 112. In some embodiments, the outer circumferential alignment interface 384 is also adapted to establish a relatively tight fluid seal once assembled inside the cylinder 104. Furthermore, the distal end 402 of the sleeve 112 includes at least three inner retaining features 372 for matingly and securely engaging the nozzle 110 on the circumferentially inner alignment interfaces / surfaces 388, 398, 399. These inner alignment interfaces 388, 398, 399 are adapted to axially and radially align the nozzle 110 relative to the sleeve 112. In some embodiments, once assembled inside the cylinder 104, the inner alignment interfaces 388, 398, 399 of the sleeve 112 also establish relatively tight fluid seals at their respective locations. Thus, the cylinder sleeve 112 can align the nozzle 110 axially and radially relative to the shroud 114.

[0068] In some embodiments, regarding the protective gas flow, a plurality of orifices 412 are circumferentially arranged around the proximal end 404 of the hollow body of the jacket 112. Each orifice 412 is configured to connect the inner surface of the hollow body of the jacket 112 to the outer surface of the hollow body at the proximal end 404. In some embodiments, each orifice 412 is oriented substantially perpendicular to the longitudinal axis A. Furthermore, each orifice 412 is shaped and sized to meter and guide the protective gas flow from the torch body 102 to the shroud 114 via the jacket 112 when engaged between the torch body 102 and the cylinder 104. More specifically, as Figure 2 As shown, when the torch body 102 and the cylinder 104 are engaged, at least a portion of the torch connector 124 of the torch body 102 is adapted to fit within a cavity defined by the proximal end 404 of the cylinder jacket 112, such that a set of orifices 126 on the outer diameter of the connector 124 are axially aligned with the orifices 412 of the proximal end 404 of the jacket 112. This axial alignment allows protective gas from the torch body 102 to flow through the orifices 126 of the connector 124 and the orifices 412 of the jacket 112 to the shroud 114.

[0069] In some embodiments, the diameter of each orifice 412 is designed to be sized according to the operating current requirements of the cylinder 104. Therefore, different cylinders 104 intended for different operating currents may have orifices 412 of different sizes. For example, the protective flow pressure of the cylinder 104 can be predefined, and the orifice size is designed to provide optimal cutting performance for each cut at the predefined protective flow pressure. Reference will be made below. Figure 9Details regarding the flow of protective gas within the plasma torch 10 are described. In some embodiments, the diameter of each orifice 412 varies from approximately 0.040 inches to approximately 0.055 inches based on the ampere number of the operating current. In some embodiments, the shape (i.e., radius) of the orifice 412 also affects the flow rate of the protective gas through the orifice 412.

[0070] Furthermore, the inner surface of the proximal end 404 of the jacket 112 may define one or more circumferential grooves 410. Figure 4a (as shown in the image), for accommodating and / or receiving flexible seal 122 ( Figure 2 As shown in the diagram, the flexible seal 122 provides a relatively tight fluid seal between the outer surface of the connector 124 of the torch body 102 and the inner surface of the proximal end 404 of the jacket 112. For example, two flexible seals 122 may be placed on either side of orifices 126 and 412 to guide radial protective gas flow through these orifices. The seal 122 also prevents liquid coolant leakage when the liquid coolant flows axially between the axial channel 128 of the connector 124 and the jacket 112, as will be described in detail below. In some embodiments, the proximal end 404 of the jacket 112 (including the seal 122) establishes a flexible, non-rigid engagement between the jacket 112 and the torch body 102 (i.e., at the outer diameter of the torch connector 124 of the torch body 102) without driving any axial and / or radial alignment between the torch body 102 and the jacket 104.

[0071] In some embodiments, regarding liquid coolant flow, a plurality of axial coolant flow passages 414 are formed between the inner surface of the distal end 402 of the jacket 112 and the corresponding outer surface of the nozzle 110. The flow passages 414 include a plurality of axial slots 414c disposed / etched into the inner surface of the distal end 402 of the jacket 112 and circumferentially distributed around the hollow body of the distal end 402. When the nozzle 110 and the jacket 112 are engaged, the axial slots 414c are configured to complement the outer profile of the nozzle 110 located within the hollow body of the jacket 112, thereby commensurately defining the corresponding liquid coolant passages 414 between the nozzle 110 and the jacket 112. Figure 4a As shown, each axial channel 414 may have a circumferential channel 176 ( Figure 2(As shown in the diagram) A proximal opening 414a in fluid communication, and a circumferential channel 176 defined at least partially by the interior of the radially extending proximal end 404 of the jacket 112. For example, once the torch body 102 is coupled to the cylinder 104, the circumferential channel 176 can be defined in mate with the torch connector 124. The circumferential channel 176 is adapted to fluidly connect one or more of the proximal openings 414a of the axial channels 414 in the cylinder 104 to one or more of the distal openings 128b of the axial channels 128 in the torch connector 124 located at the proximal end 404 of the jacket 112 for conveying a flow of liquid coolant to or from the torch body 102. In some embodiments, the axial channels 414 of the cylinder 104 are circumferentially and uniformly distributed in the cylinder 104 such that (i) at least one axial channel 414 is adapted to be in fluid communication with at least one of the axial channels 128 of the first group 178 in the torch connector 124 and (ii) at least another axial channel 414 is adapted to be in fluid communication with at least one of the axial channels 128 of the second group 182, which is radially opposite the first group 178 at approximately 180 degrees. Furthermore, each axial channel 414 also has a circumferential channel 134 located distal to the distal opening 414b of the coolant passage 414. Figure 2 (As shown in the diagram) A distal opening 414b in fluid communication, wherein a circumferential channel 134 may extend about 360 degrees around the nozzle 110. The circumferential channel 134 may be defined by a circumferential slot 134a disposed / etched into the outer surface of the nozzle 110 and a corresponding circumferential inner surface 134b of the jacket 112. After the coolant flow exits from the coolant passage 414, the circumferential channel 134 allows coolant to circulate around the outer surface of the end of the nozzle 110, thereby promoting convective cooling of the nozzle end and reducing stagnation of the flowing liquid during torch operation. Generally, the combination of the axial coolant passage 414 and the circumferential coolant channel 134 enhances the cooling of at least a portion of the nozzle 110 located within the jacket 112.

[0072] In some embodiments, a fluid-impermeable seal 130 is formed between the inner surface of the proximal end of the jacket 112 and the outer surface of the nozzle 110. Figure 2 (As shown in the diagram) Located immediately adjacent to the distal side of the circumferential channel 134. As described above, the seal 130 is configured not only to attach the jacket 112 to the nozzle 110 to form the alignment surface 399, but also to prevent liquid coolant leakage in the distal direction from the coolant passage 414 and the circumferential coolant passage 134. Furthermore, in addition to providing a flexible engagement interface between the torch body 102 and the barrel 104, the seal 122 between the torch connector 124 and the proximal end 404 of the barrel jacket 112 prevents liquid coolant leakage in the proximal direction from the coolant passage 414. Reference will be made below. Figure 10 Describe in detail the flow of liquid coolant inside the plasma torch 10.

[0073] In some embodiments, regarding the alignment of the torch body 102 and the cylinder 104 during engagement, the cylinder clamp 112 is configured such that the nozzle 110 of the cylinder 104 can achieve and / or primarily guide such alignment. Specifically, as... Figure 3a As shown, the proximal end 404 of the jacket 112 mates with the proximal portion of the nozzle 110 extending within the proximal end 404 of the jacket 112, defining a cavity 350. The cavity 350 is radially defined by the circumferential body 404a of the proximal end 404 of the jacket 112 and the outer contour of the nozzle 110 extending within the proximal end 404. The cavity 350 is axially defined by the stepped inner wall 404b of the proximal end 404. When the cartridge 104 is mounted onto the distal end 22 of the torch body 102, the coolant tube 116 of the torch body 102 is adapted to be inserted into the central cavity of the electrode 108 of the cartridge 104, while the torch connector 124 of the torch body 102 is inserted into the cavity 350 within the proximal end 404 of the jacket 112 of the cartridge 104. During engagement, the outer diameter of connector 124 is flexibly engaged to the circumferential body 404a of proximal end 404 via one or more flexible seals 122, while the inner diameter of connector 124 is rigidly engaged to the outer contour of the portion of nozzle 110 in proximal end 404. Figure 2 As shown, this rigid engagement with the nozzle 110 forms a circumferential interface / surface 132 between the connector 124 and the nozzle 110, which drives the axial and radial alignment between the torch body 102 and the cylinder 104.

[0074] In some embodiments, because the proximal end 404 of the sleeve 112 is exposed during the assembly of the sleeve 104 (e.g. Figure 3b As shown in the diagram, the proximal end 404 extends axially and radially beyond the coverage of the shroud 114, so the outer surface of the proximal end of the sleeve 112 can be marked with useful information to assist the end user. For example, as... Figure 4b As shown, the outer surface of the proximal end 404 may be marked with large, raised lettering to indicate that the corresponding cylinder 104 should be used in accordance with its operating current ampere 420 and / or the single part number assigned to cylinder 104. Furthermore, this large, raised lettering (and / or additional raised features) provides a gripping surface for the end user during the installation / removal of cylinder 104 relative to torch body 102, compatible with tool-free installation / removal processes. For example, the end user can simply push cylinder 104 onto the distal end 22 of torch body 102 for installation and pull cylinder 104 away from the distal end 22 of torch body 102 for removal. Without these gripping features, cylinder 104 may be slippery when wet, especially when using liquid coolant, which could hinder manual installation and / or removal of the cylinder. Moreover, because the exposed proximal end 404 of the cylinder jacket 112 is constructed of a non-conductive material, the proximal end 404 provides electrical insulation and protection to the end user during tool-free installation / removal processes.

[0075] As described above and herein, the sleeve 112 of the present invention provides a variety of functions in a compact design that improve both torch operation and torch usability. Operational functions provided by the sleeve 112 include, but are not limited to, radial and axial alignment of the shroud 114 relative to the nozzle 110; alignment and retention of the nozzle 110 and shroud 114 while establishing a relatively tight fluid seal at their respective interfaces; enabling the nozzle 110, located within the sleeve 112, to drive the alignment of the sleeve 104 relative to the torch body 102; guiding a flow of liquid coolant between the torch body 102 and the nozzle 110 via an axial channel 414 to extensively cool the nozzle 110; metering of protective gas via a set of orifices 412 to control gas flow; and establishing electrical isolation between the shroud 114 and the nozzle 110. Usability functions provided by the sleeve 112 include, but are not limited to, establishing a gripping surface for tool-free installation / removal of the sleeve 104 relative to the torch body 102; protecting the end user by extending electrical insulation beyond the proximal end of the shroud 114; and visible sleeve markings. Generally, the jacket 112 combines many complex features and stringent tolerance requirements that are traditionally distributed among many consumable components in a typical plasma torch into a single component. This simplification is beneficial for reducing manufacturing costs and assembly problems.

[0076] Figure 5 Some embodiments according to the present invention are shown. Figure 2 An external outline view of an exemplary configuration of the nozzle 110 of the plasma torch 104 is shown. As shown, the nozzle 110 has a substantially hollow body and generally includes a proximal end 602, a middle section 604, and a distal end 606 extending along the longitudinal axis A of the plasma torch 10. The nozzle 110 may be made of a conductive material such as copper.

[0077] like Figure 3a As shown, the proximal end 602 of the nozzle 110 is adapted to extend and hang within the proximal end 404 of the sleeve 112 during assembly of the cylinder 104. Specifically, a radial flange 608 extending from the outer surface of the proximal end 602 is adapted to abut against a stepped inner wall portion 404b of the proximal end 404 of the sleeve 112 to prevent axial advancement of the proximal end 602 of the nozzle 110 within the sleeve 112. In some embodiments, the outer diameter / profile of the proximal end 602 of the nozzle 110 is adapted to matingly and rigidly engage the torch connector 124 of the torch body 102 during torch assembly, thereby forming an alignment interface / surface 132 that drives the cylinder 104 to axial and / or radial alignment relative to the torch body 102, as described above.

[0078] The intermediate segment 604 of the nozzle 110 is configured to insert into the distal end 402 of the sleeve 112 such that the distal end 402 of the sleeve 112 substantially surrounds the intermediate segment 604. The intermediate segment 604 is adapted to contact the inner surface of the distal end 402 of the sleeve 112 at various circumferential interfaces 388, 398, 399, thereby driving the sleeve 112 to radially and axially align relative to the nozzle 110. Furthermore, the outer surface / profile of the intermediate segment 604 of the nozzle 110 is adapted to mate with a plurality of axial coolant slots 414c disposed in the inner surface of the distal end 402 of the sleeve 112 to form a plurality of coolant passages 414 extending axially on the outer surface of the intermediate segment 604. In some embodiments, the intermediate segment 604 includes a circumferential slot 134a disposed / etched in the outer surface of the nozzle 110, which mates with a corresponding circumferential inner surface 134b of the sleeve 112 to define a circumferential coolant passage 134. In some embodiments, the intermediate segment 604 includes a circumferential groove 610 located immediately adjacent to the distal side of the circumferential slot 134a. The circumferential groove 610 is configured to receive a seal 130 located between the jacket 112 and the nozzle 110. Figure 2 (As shown in the image) to prevent fluid leakage.

[0079] The distal section 606 of the nozzle 110 includes a centrally located nozzle outlet orifice 612 for introducing a plasma arc, such as an ionized gas jet, into the workpiece to be cut (not shown). The distal section 606 is adapted to extend axially through and beyond the opening of the distal portion 402 of the sleeve 112 when the sleeve 104 is assembled.

[0080] Figure 6a and Figure 6b Some embodiments according to the present invention are shown. Figure 2 The figures show an external profile view and a cross-sectional profile view of an exemplary configuration of the vortex ring 150 of the cylinder 104. As shown, the vortex ring 150 has a substantially hollow, elongated body extending along a longitudinal axis A between a proximal end 502 and a distal end 504. The vortex ring 150 may be made of a non-conductive material such as an injection-molded plastic material (e.g., Randel). Therefore, the vortex ring 150 can be manufactured using injection molding technology.

[0081] In some embodiments, the vortex ring 150 includes a plurality of slots 506 formed at a distal end 504 on the outer surface of the hollow body, wherein the slots 506 are circumferentially distributed around the vortex ring 150. The slots 506 are shaped to complement the internal profile of the nozzle 110 to define a set of gas vortex paths oriented to impart a tangential velocity component to the plasma gas flow traveling between the vortex ring 150 and the nozzle 110. For example, as... Figure 6aAs shown, the slot 506 can be tilted / twisted to form a vortex pattern on the outer surface of the vortex ring 150. This vortex generates vortices that contract the plasma arc from the electrode 108 and stabilize the position of the arc on the insert of the electrode 108.

[0082] In some embodiments, the hollow body dimension of the eddy ring 150 is designed to receive at least a portion of the electrode 108. (Refer to the above text) Figure 3a and Figure 3b The eddy ring 150 includes at least one inner retaining feature 368 for mating and securely engaging the electrode 108 on the circumferentially inner alignment interfaces / surfaces 390, 392. The eddy ring 150 also includes at least one outer retaining feature 352 for mating and securely engaging the nozzle 110 on the circumferentially outer alignment interfaces / surfaces 394, 396. Therefore, the eddy ring 150 can align the nozzle 110 axially and radially relative to the electrode 108 on various alignment interfaces / surfaces.

[0083] Figure 7 Some embodiments according to the present invention are shown. Figure 2 A cross-sectional view of an exemplary configuration of the electrode 108 of the tube 104. As shown, the electrode 108 has an elongated body extending along the longitudinal axis A of the plasma torch 10 between a proximal end 702 and a distal end 704. The electrode 108 defines an internal cavity 708 having an opening exposed from the proximal end 702. The internal cavity 708 is configured to receive at least a portion of the coolant tube 116 during torch assembly. An emission insert 706 may be disposed on the distal end 704 of the electrode 108, thereby exposing the emission surface. The insert 706 may be made of hafnium, silver, and / or other materials having suitable physical properties, including corrosion resistance and high thermionic emissivity. In some embodiments, the insert 706 is made of silver with a hafnium center. This configuration has several advantages, including providing extended cutting power and a long consumption life of the tube 104 via the plasma torch 10.

[0084] Figure 8 Some embodiments according to the present invention are shown. Figure 2 An external profile view of the shroud 114 of the plasma torch 104. The shroud 114 includes a substantially hollow body defining a proximal end 802 and a distal end 804 disposed along the longitudinal axis A of the plasma torch 10. The distal end 804 includes a centrally located shroud outlet orifice 806 and a set of one or more vent holes 808 optionally extending from an inner surface to an outer surface of the shroud 114. The shroud 114 may be formed of a conductive material such as copper. As described above, the proximal end 802 of the shroud 114 may include a retaining feature 364 circumferentially disposed around the inner surface of the proximal end 802. Figure 3a (As shown in the diagram). The retaining feature 364 is configured to complement the corresponding retaining feature 362 of the sleeve 112 to hold the cover 114 on the interface 384 ( Figure 3a (As shown in the figure) It is securely engaged / attached to the collet 112.

[0085] In some embodiments, a set of orifices 810 are circumferentially disposed around the proximal end 802 of the hollow body of the shroud 114, wherein each orifice 810 is configured to connect an outer surface of the hollow body to an inner surface of the hollow body. Each orifice 810 is sized and shaped to guide, meter, and swirl a protective gas flow traveling through the orifice 810 toward the shroud outlet orifice 806. In some embodiments, eight to ten of these orifices 810 are distributed around a circumference at the proximal end 802 of the shroud 114. In some embodiments, the diameter of each orifice 810 may be from about 0.039 inches to about 0.043 inches, depending on the operating current. In some embodiments, the orifices 810 are drilled in an offset manner. The orifices 810 may be machined into the proximal end 802 of the shroud 114, such as drilling them into the shroud body as holes. In some embodiments, the orifices 810 are offset and / or angled to impart a tangential velocity component to the protective gas flow passing through the orifices 810, thereby forming a vortex pattern in the protective gas flow. Generally, the size, number, and / or location of these orifices 810 can be adjusted for specific current amperes to achieve the desired cutting performance. Details regarding the protective gas flow through the plasma torch 10 (including through the shield 114) are detailed below. Figure 9 supply.

[0086] In some embodiments, the shroud 114 is directly cooled by a flow of liquid coolant. More specifically, a circumferential channel 812 may be formed / etched into the outer surface of the proximal end 802 of the shroud 114 and oriented around the proximal end 802 (e.g., extending about 360 degrees around the proximal end 802). The circumferential channel 812 is adapted to circulate the liquid coolant flow around the outer surface of the shroud 114, thereby promoting convective cooling of the shroud and reducing stagnation of the flowing liquid during torch operation. In some embodiments, after being attached to the external geometry of the cylinder 104 and the torch body 102, the outer cap 120 is in fluid communication with the circumferential channel 812 to deliver liquid coolant from the torch body 102 to the shroud 114 and from the shroud 114 to the torch body 102. The following is in conjunction with... Figure 10 Details are provided regarding the flow of liquid coolant through the plasma torch 10 (including through the shield 114).

[0087] Therefore, the shroud 114 combines protective gas swirling (at orifice 810) with direct liquid cooling (at circumferential channel 812) in a single compact component. Traditionally, the protective gas swirling is separate from the shroud 114 itself. For example, separate and distinct inner caps of plasma torches are typically used to provide protective gas swirling before the swirling gas is delivered to the shroud. Moving the protective gas swirling feature from the inner cap to the shroud 114 is advantageous, at least because different and customized protective gas swirling can be formed for torch operation at different amperes without the need for cumbersome installation of different inner caps. Thus, an inner cap for the cylinder 104 is no longer required. Generally, the shroud 114 may have orifices 810 of different numbers, sizes, and / or shapes (e.g., offset) to produce the desired cutting angle per ampere.

[0088] Figure 9 Some embodiments according to the present invention are shown. Figure 2 A cross-sectional view of a plasma arc torch 10, oriented to illustrate an exemplary protective gas flow path 902 from the torch body 102 to the cartridge 104 of the torch 10. As shown, the torch body 102 provides a protective gas flow to the cartridge 104 via a torch connector 124 of the torch body 102. More specifically, a plurality of orifices 126 of the torch connector 124 are configured to guide and meter the protective gas flow 902 from the torch body 102 to the cartridge 104. When the cartridge 104 is mounted to the torch body, a plurality of orifices 412 circumferentially disposed around the proximal end 404 of the hollow body of the jacket 112 are adapted to be axially aligned with the orifices 126 of the torch connector 124. Thus, the plasma gas flow 902 is radially outwardly delivered from the orifices 126 to the orifices 412, where the plasma gas flow 902 is metered and guided from the inner surface of the cartridge jacket 112 to the outer surface of the jacket 112. Upon exiting orifice 412, the protective gas flow 902 is further conveyed to a protective gas flow passage 904 defined between the outer surface of the jacket 112 and the inner surface of the cap liner 120b of the outer cap 120. The protective gas flow 902 is adapted to travel distally within the protective gas flow passage 904 to reach the outer surface of the proximal end 802 of the shield 114. The protective gas flow 902 can then travel via a plurality of vortex orifices 810 circumferentially arranged around the proximal end 802. Figure 8(As shown in the diagram) Flows from the outer surface of the protective gas 114 to the inner surface of the protective gas 114. As described above, the orifice 810 is shaped and sized to impart a tangential velocity component to the protective gas flow 902 passing through the orifice 810, thereby forming a vortex pattern in the protective gas flow 902. Upon exiting the orifice 810, the protective gas 902 is adapted to flow distally via a gas flow passage 906, which is defined between the inner surface of the protective gas 114 and the outer surface of the combination of the sleeve 112 and the distal end 606 of the nozzle 110 disposed within the hollow body of the protective gas 114. The gas flow passage 906 is configured to deliver the protective gas flow 902 to the protective gas outlet orifice 612 for discharge of protective gas from the tip of the torch 10.

[0089] Figure 10 Some embodiments according to the present invention are shown. Figure 2 A cross-sectional view of a plasma torch, oriented to an exemplary liquid coolant flow path 1002 circulating between the torch body 102 and the cylinder 104 of the torch 10. In some embodiments, such a cooling flow 1002 is in accordance with the above-referenced... Figure 9 The protective gas flow 902 is executed at essentially the same time. Along the liquid coolant flow path 1002, the liquid coolant is first introduced from the torch body 102 into the cylinder 104 via the coolant tube 116. The coolant flow 1002 is configured to travel distally within the coolant tube 116 and exit through a distal opening. Upon exiting the coolant tube 116, the liquid coolant flow 1002 enters the central cavity 708 of the electrode 108 within the cylinder 104, which contains the coolant tube 116, thereby significantly cooling the electrode 108. Guided by the walls of the cavity 708, the coolant flow 1002 reverses direction and continues proximally within the cavity 708 along the outer surface of the coolant tube 116. The coolant flow 1002 continues toward the cathode 170 of the torch body 102 and flows radially outward into the torch insulator 118 via an orifice 1004 disposed on the body of the cathode 170, wherein the orifice 1004 is in fluid communication with an axial channel 1006 disposed inside the torch insulator 118. The axial channel 1006 is configured to be in fluid communication with the axial channels 128 of the first set 178 disposed in the torch connector 124. Once inside the insulator 118, the coolant 1002 flows distally through the axial channel 1006 and enters one or more of the axial channels 128 of the first set 178 in the torch connector 124.

[0090] As the coolant flow 1002 exits from the distal opening 128b of one or more of the axial channels 128 in the first set 178 of the torch body 102, the coolant flow 1002 is adapted to enter the barrel 102 via a circumferential channel 176 defined between the torch connector 124 and the proximal end 404 of the barrel jacket 112. From there, the coolant flow 1002 may enter one or more of the coolant passages 414 defined between the jacket 112 and the nozzle 110 via corresponding proximal openings 414a of the passages 414. Once within the coolant passages 114, the coolant flow 1002 is adapted to flow distally toward the corresponding distal opening 414b and into a circumferential channel 134 located distal to the distal opening 414b, wherein the circumferential channel 134 is defined by a circumferential slot 134a disposed / etched into the outer surface of the nozzle 110 and a corresponding circumferential inner surface 134b of the jacket 112. The coolant flow 1002 is adapted to circulate within the circumferential channel 134 and around the outer surface of the distal end of the nozzle 110, thereby convectively cooling the tip of the nozzle 110. Furthermore, the coolant flow 1002 is adapted to return to the torch body 102 by flowing distally through one or more of the axial channels 128 of the second group 182 (located at approximately 180 degrees radially offset from the axial channels 128 of the first group 178) via one or more of the coolant flow passages 414 in fluid communication with the axial channels 128 of the second group 178.

[0091] Once inside one or more of the axial channels 128 of the second set 182 in the torch connector 124, the coolant flow 1002 is adapted to flow distally into the axial channel 1008 in the insulator 118 of the torch body 102. In some embodiments, the axial channels 1008 and 1006 are radially offset relative to each other in the torch insulator 118, such as by about 180 degrees. Thereafter, the coolant flow 1002 exits from the axial channel 1008 and travels radially outward into the coolant passage 1010 defined between the cap liner 120b and the cap shell 120a of the outer cap 120. The coolant 1002 is conducted proximally through the coolant passage 1010 toward the circumferential channel 812 disposed on the outer surface of the proximal end 802 of the shroud 114. Once in the circumferential channel 812, the coolant flow 1002 is adapted to circulate around the outer surface of the shroud 114 to convectively cool the shroud 114, and exit from the channel 812 on the other side of the shroud 114, substantially opposite to the location where the coolant flow enters the circumferential channel 812. From there, the coolant flow 1002 is adapted to return to the torch body 102 by flowing proximally in the axial channel 1012 defined between the cap liner 120b and the cap shell 120a of the outer cap 120. In some embodiments, the axial channels 1010 and 1012 are radially offset relative to each other, such as by about 180 degrees.

[0092] Figure 11a and Figure 11b A cross-sectional profile view of another exemplary plasma arc torch 1300 with different configurations to provide a variable protective gas flow rate according to some embodiments of the present invention is shown. As shown, the torch 1300 includes a torch body 1302 and a consumable belt jacket 1304. The torch body 1302 of the plasma arc torch 1300 may be substantially similar to Figure 2 The plasma arc torch 10 has a torch body 102 that differs in that two sets of orifices 1306 and 1308 are provided on the torch connector 1324 of the torch body 102, instead of a single set of orifices 412 circumferentially provided on the torch connector 124 of the torch body 102. The two sets of orifices 1306 and 1308 are axially spaced apart from each other and are both configured to conduct protective gas through their respective counterparts in the orifices for delivering protective gas from the torch body 1302 to the cylinder 1304.

[0093] In some embodiments, the cylinder 1304 of the plasma torch 1300 is substantially similar to the cylinder 104 of the plasma torch 10, except that the axial length 1316 of the sleeve 1310 of the cylinder 1304 is designed to be variable to selectively cover (e.g., to provide a fluid-impermeable seal) one or none of the two sets of orifices 1306, 1308, depending on the operating current requirements of the cylinder 1304. Therefore, if a “high” gas flow range is desired, the axial length 1316 of the sleeve 1310 can be designed to be short, such that the proximal end 1318 of the sleeve 1310 exposes both sets of orifices 1306, 1308, thereby allowing protective gas to flow through both sets of orifices, as described above. Figure 11a The protective gas flow path 1312 is illustrated. Conversely, if a "low" gas flow range is desired, the axial length 1316 of the jacket 1310 can be designed to be relatively long, such that the proximal end 1318 of the jacket 1310 covers the distal group of orifices 1308, but exposes the proximal group of orifices 1306, as shown by... Figure 11b The protective gas flow path 1312 is illustrated. In some embodiments, the protective gas pressure is then adjusted to achieve the protective gas flow rate required for the process. For example, for a given cutting process and given the geometry of the consumables used, the protective gas flow rate can be optimized to obtain good cutting quality. Essentially, controlling the protective gas flow rate by manipulating orifices 1306, 1038 can be used to achieve desired cutting characteristics.

[0094] In some embodiments, the size (e.g., diameter) of the proximal orifice 1306 may differ from the size (e.g., diameter) of the distal orifice 1308 to achieve a desired gas flow rate. In some embodiments, more than two sets of orifices may be provided on the torch connector 124 of the torch body, wherein the multiple sets of orifices are axially spaced relative to each other. Therefore, the axial length of the adjustable jacket 1310 can be used to cover / seal one or more of the multiple sets of orifices, thereby further refining the protective gas flow rate adjustment.

[0095] Figure 12 Some embodiments according to the present invention are shown. Figure 11a and Figure 11b A set of exemplary performance results for different configurations of the plasma torch 1300. To produce these results, the diameters of the two sets of orifices 1306, 1308 are set to be approximately the same, but vary for different performance evaluations. These diameters can range from about 0.04 inches to about 0.07 inches, as indicated in Figure 1402. More specifically, at each unique diameter, the two orifices 1306, 1308 are configured to have approximately the same diameter value, and in (i) as shown in Figure 1402. Figure 11b The construction shown in the figure exposes only one orifice 1306 and (ii) as Figure 11a The protective gas flow rate was measured with two orifices 1306 and 1308 exposed as illustrated in the diagram. Therefore, for Figure 12 The coordinate graph shows that each unique diameter corresponds to two performance lines. One line, labeled "2H - Diameter Value," indicates that both orifices are exposed at that specific diameter value, while the other line, labeled "Diameter Value," indicates that only one orifice is exposed at that diameter value. Generally, the lower line of each pair (at the same diameter value) represents a single orifice 1306 conducting the protective gas, and the upper line of each pair (at the same diameter value) represents two orifices 1306 and 1308 of the same size conducting the protective gas. As shown, covering one or two sets of these orifices provides the full range of protective gas flow rates required for most cutting processes. More specifically, it allows two sets of orifices 1306 and 1308 to conduct the protective gas (e.g., ...). Figure 11a (As illustrated in the diagram) Protective gas flow rates between approximately 135 scfh (standard cubic feet per hour) and approximately 330 scfh can be achieved. Only the protective gas (such as...) is allowed to conduct through the proximal group orifice 1306. Figure 11b (As illustrated in the figure) Protective gas flow rates between approximately 70 scfh and approximately 170 scfh can be achieved. Furthermore, different diameter sizes (e.g., 0.040” inch instead of 0.050” inch) provide slightly different total protective gas flow rate ranges, but have a flow rate trend that is substantially similar to that of other diameter sizes.

[0096] Figure 13 The illustrations depict assembly according to some embodiments of the present invention. Figure 2An exemplary process 1500 of the consumable jacket sleeve 104 of the liquid-cooled plasma torch 10. Process 1500 begins by securely attaching a vortex ring 150 to the distal end of an electrode 108 such that the vortex ring 150 is circumferentially positioned around the distal end of the electrode 108 (step 1502). This secure attachment forms at least two alignment interfaces 390, 392 between the vortex ring 150 and the electrode 108, which align the two components radially and axially relative to each other. A nozzle 110 is securely attached to the vortex ring 150 such that the nozzle 110 is circumferentially positioned around the distal end of the electrode 108, with a portion of the vortex ring 150 located between the nozzle 110 and the electrode 108 (step 1504). In some embodiments, when the nozzle 110 is securely attached to the vortex ring 150, a secure attachment of the vortex ring 150 and the electrode 108 is achieved, thereby applying external pressure to the engagement / alignment interface between the vortex ring 150 and the electrode 108. The secure attachment between the nozzle 110 and the vortex ring 150 forms at least two alignment interfaces 394, 396 between them, which align the two components radially and axially relative to each other. A collet 112 is securely attached to the distal end of the nozzle 110 such that the collet 112 is circumferentially disposed around the distal end of the nozzle 110 (step 1506). This secure attachment forms two or more (e.g., three) alignment interfaces 399, 398, 399 between the nozzle 110 and the collet 112, which align the two components radially and axially relative to each other. Furthermore, the shroud 114 can be securely attached to the distal end of the sleeve 112 such that the shroud 114 is circumferentially disposed around the sleeve 112, wherein the proximal end 404 of the sleeve 112 extends axially through the proximal end 802 of the shroud 114 and extends radially beyond the radial extent of the shroud 114 (step 1508). This secure attachment forms at least one alignment interface 384 between the sleeve 112 and the shroud 114, which aligns the two components radially and axially relative to each other. Thus, the shroud 114 is axially and radially aligned with (and electrically isolated from) the nozzle 110 via the sleeve 112, which can be formed from an injection-molded material. In some embodiments, one or more alignment interfaces implemented throughout the cylinder 102 also serve as fluid seals (e.g., liquid and / or gas seals) at their corresponding locations. In some embodiments, the secure attachment / engagement of the various components of the cylinder 104 is permanent for the service life of the cylinder.

[0097] Figure 14An exemplary process 1600 for selecting and installing a desired consumable cartridge for a plasma torch, according to some embodiments of the present invention, is illustrated. Process 1600 begins by providing a first consumable cartridge with a jacket, the first consumable cartridge including a jacket configured to achieve a first desired protective gas flow rate corresponding to a first operating current requirement of the cartridge (step 1602). The jacket of the first cartridge may be constructed similarly to... Figure 2 The jacket 112 or Figure 11a and Figure 11b The jacket 1310. More specifically, if the jacket of the first cylinder is similar to... Figure 2 The jacket 112 includes a set of protective gas orifices 412 circumferentially disposed on the proximal end of the jacket, wherein the orifice dimensions are designed to meter and guide the gas flow therethrough at a first desired flow rate. If the jacket of the first consumable cylinder is similar to... Figure 11a and Figure 11b The jacket 1310 is configured to cover one or two sets of protective gas orifices 1306, 1306 in the torch body to achieve the first desired flow rate.

[0098] A second consumable jacketed sleeve is provided, comprising a jacket configured to achieve a second desired protective gas flow rate corresponding to a second operating current requirement of the second sleeve, which is different from the first operating current (step 1604). The jacket of the second sleeve may be constructed similarly to... Figure 2 The jacket 112 or Figure 11a and Figure 11b The jacket 1310. More specifically, if the jacket of the second cylinder is similar to... Figure 2 The jacket 112 includes a set of protective gas orifices having a different size (e.g., diameter) than the protective gas orifices of the first cylinder, to achieve different flow rates and operating current requirements. If the jacket of the second consumable cylinder is similar to... Figure 11a and Figure 11b The jacket 1310 is configured to have an axial length different from that of the jacket in the first cylinder to achieve different flow rates and operating current requirements. The different axial lengths of the jacket are suitable for covering different numbers of corresponding protective gas orifices in the torch body to achieve different operating current requirements.

[0099] The operator can select one of the first or second cylinders as the desired consumable cylinder by comparing the desired operating current with the different operating current requirements associated with the first and second cylinders (step 1606). The operator can then install the selected consumable cylinder onto the torch body to fully assemble the torch (step 1608). In some embodiments, for the selected cylinder, the diameter of the protective gas orifice 810 disposed in the body of the shroud 114 is also appropriately sized and optimized to support the cylinder's operating current requirements.

[0100] It should be understood that various aspects and embodiments of the present invention can be combined in various ways. Based on the teachings of this specification, those skilled in the art can readily determine how to combine these various embodiments. Modifications will also arise in the minds of those skilled in the art upon reading this specification.

Claims

1. A protective shield for a liquid-cooled plasma torch, the shield comprising: It is basically a hollow body, with a proximal end and a distal end; The protective cover outlet hole is centrally located at the distal end of the hollow body; A retaining feature is provided at the proximal end of the hollow body; A circumferential liquid cooling channel is disposed in the outer surface of the body, and the liquid cooling channel is configured to circulate the liquid coolant around the outer surface; as well as At least one orifice is disposed at the proximal end of the hollow body, the at least one orifice being configured to guide a flow of protective gas passing through it toward the shroud outlet orifice.

2. The protective cover according to claim 1, further comprising one or more vent holes extending from the inner surface of the protective cover to the outer surface.

3. The protective cover according to claim 1, wherein, The at least one aperture includes a plurality of apertures circumferentially disposed around the proximal end of the hollow body, each aperture being configured to connect the outer surface of the hollow body to the inner surface of the hollow body.

4. The protective cover according to claim 1, wherein, The diameter of the at least one orifice is between approximately 0.039 inches and approximately 0.043 inches.

5. The protective cover according to claim 1, wherein, The at least one orifice is either offset or angled to impart a tangential velocity component to the protective gas flow passing through it, thereby forming a vortex pattern in the protective gas flow.

6. The protective cover according to claim 1, wherein, The retaining feature is disposed in the inner surface of the hollow body for engaging the jacket of the plasma torch.

7. The protective cover according to claim 1, wherein, The protective cover is part of a consumable cylinder, which further includes one or more of an electrode, a nozzle, a jacket, and a vortex ring, and wherein the consumable cylinder is an integral component such that each of the protective cover, the electrode, the jacket, and the vortex ring is not individually repairable or disposable.

8. The protective cover according to claim 6, wherein, The proximal end of the sleeve is adapted to (i) extend axially through the proximal end of the hollow body of the shroud, and (ii) extend radially beyond the radial extent of the shroud.

9. The protective cover according to claim 6, wherein, The retaining feature is adapted to complement the corresponding retaining feature of the jacket to form a circumferential interface, the circumferential interface being configured to provide at least one of the following: (i) axial and radial alignment of the shield with respect to the jacket, or (ii) a fluid seal between the shield and the jacket.

10. The protective cover according to claim 1, further comprising a gas flow passage disposed inside the hollow body of the protective cover and in fluid communication with the at least one orifice, the gas flow passage being configured to axially deliver the protective gas flow from the at least one orifice to the outlet orifice of the protective cover.

11. The protective cover according to claim 1, wherein, A portion of the outer surface of the hollow body of the shield is adapted to come into contact with a liquid coolant fluid used to cool the shield.

12. A method for operating a shroud for a liquid-cooled plasma arc torch, the method comprising: The shield receives a protective gas flow delivered from the torch body of the plasma arc torch, wherein the shield comprises a substantially hollow body defining a proximal end and a distal end. The protective gas flow is guided on the outer surface of the hollow body of the shield; The protective gas flow is guided from the outer surface of the hollow body to the inner surface of the hollow body through a plurality of orifices arranged circumferentially around the proximal end of the hollow body; As the protective gas flow exits the orifice, it is directed distally towards the shield outlet orifice, which is centrally located at the distal end of the hollow body; and The protective gas flow is discharged from the distal end of the hollow body through the outlet hole of the protective cover.

13. The method of claim 12, further comprising: As the protective gas flow is guided through the plurality of orifices, a tangential velocity component is assigned to the protective gas flow.

14. The method according to claim 12, wherein, The protective gas flow is guided distally toward the outlet hole of the shield via a gas flow passage, the gas flow passage being configured to be between the inner surface of the shield and the outer surface of the combination of the jacket and the distal end of the nozzle disposed within the hollow body of the shield.

15. The method of claim 12, further comprising: The coolant flow from the torch body is received on the first side of the shield through a circumferential channel, wherein the circumferential channel is disposed in the outer surface of the hollow body of the shield at the proximal end of the hollow body. The coolant is circulated around the outer surface at the proximal end of the hollow body through the circumferential channel to convectively cool the shield. as well as The coolant flow is returned to the torch body.

16. The method according to claim 15, wherein, The coolant flow exits the circumferential channel from the second side of the shield to return to the torch body, wherein the second side is substantially circumferentially opposite the first side.

17. The method of claim 15, further comprising: The coolant flow is guided through the shield substantially simultaneously with the flow of the protective gas.

18. The method of claim 12, further comprising securely attaching the shield to a distal end of the jacket of the plasma torch such that the shield is circumferentially disposed around the jacket, wherein a proximal end of the jacket extends axially through the proximal end of the shield and radially beyond the radial extent of the shield, wherein the jacket is in turn securely attached to the nozzle of the plasma torch.

19. The method of claim 18, further comprising aligning the shield axially and radially relative to the nozzle via the jacket.

20. The method of claim 18, further comprising electrically isolating the shield and the nozzle by means of the jacket.

21. The method according to claim 18, wherein, The shield receives the protective gas flow through a plurality of orifices in the jacket, the plurality of orifices being configured to meter the gas flow and guide the gas flow from the torch body to the shield.

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