Vortex generator for plasma treatment

A vortex generator uses a single piece to generate the vortex and hold the electrode. The single piece may be a non-conductive material such as a ceramic. The vortex generator may use threads to hold the electrode. The threads and holes for generating the vortex may be bored into the base material of the vortex generator before the base material is hardened.

BACKGROUND

The present application relates generally to the field of plasma generators for treating a surface of an object with plasma.

Plasma generators have been used to treat surfaces of objects. These surfaces may be formed from materials such as plastics, rubber, glass, metals, and composites. Treating these surfaces may make it easier to bond things to the surfaces. For example, it may make it easier to apply paint, adhesives (e.g. to apply labels), coatings, laminates, and inks to the surfaces.

Plasma may be applied to surfaces for other reasons as well. Plasma may be applied to a surface to microclean a surface by removing organic and inorganic contaminants.

Plasma generators may include vortex generators that are configured to generate a vortex of working gas. In many plasma generators, the swirling gas caused by the vortex generator and an electrical arc interact to form the plasma.

Some prior vortex generators used a ceramic base material having holes at an angle to generate the vortex. These prior vortex generators included a threaded metal ring which was adhered to the ceramic base material. The metal ring was used to hold the electrode.

SUMMARY

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator includes a base material. The vortex generator is configured to generate a vortex of working gas in the plasma generator. The base material is configured to directly hold the electrode.

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator includes a base material that defines an attachment surface. The attachment surface is configured to attach to a surface of the electrode. The vortex generator is configured to generate a vortex of working gas in the plasma generator. The base material may be configured such that the electrode is releasably attached or may be configured such that the electrode is fixedly attached.

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator comprises a non-conductive base material. Threads are integrally formed in the base material. A plurality of holes are also formed in the base material. The plurality of holes are configured to receive a working gas and to generate a vortex of working gas in the plasma generator. A second hole is also formed in the base material. The second hole can receive a conductor which may attach to the electrode to supply power to the electrode.

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator comprises a base material defining threads. The vortex generator is configured to generate a vortex of working gas in the plasma generator using the base material.

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator comprises threads integrally formed in a base material. The vortex generator is configured to generate a vortex of working gas in the plasma generator.

Another embodiment is directed to a plasma generator. The plasma generator comprises a working gas inlet for receiving a working gas, a chamber in which plasma is generated, an electrode configured to generate an electrical arc, and a vortex generator arranged such that at least some of the working gas passes from the working gas inlet through the vortex generator before passing through the chamber. The vortex generator includes a base material having a plurality of holes through which working gas can pass, the holes being arranged to generate a vortex in the chamber. The base material is configured to hold the electrode.

Another embodiment provides a plasma generator. The plasma generator comprises a means for generating an electrical arc, an inlet for a gas, and a means for generating a vortex of the gas and for holding an electrode in a one-piece frame. The generator is configured such that the gas and the electrical arc interact to form plasma.

Another embodiment is directed to a plasma generator. The plasma generator comprises a gas inlet for receiving a gas, an electrode configured to generate an electrical arc, a chamber in which plasma is generated from the interaction of the gas and the electrical arc; and a vortex generator arranged such that at least some of the gas passes from the gas inlet through the vortex generator before passing through the chamber. The vortex generator is configured to swirl the gas and maintain a position of the electrode using a common body.

Another embodiment is directed to a method for forming a vortex generator. The method comprises providing a body, forming a vortex system in the body, and connecting the electrode to the body. The method may also include forming a means to connect the electrode to the body in the body. The means formed in the body could include threads.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Referring toFIGS. 6 and 7, an exemplary vortex generator500(which can be used as vortex generator36) is formed from a ceramic base502. Ceramic base502may be cylindrical or may take some other shape. Ceramic base502includes a vortex body504and an extension506. Base502also includes a lip516that extends on the opposite side of body504than extension506. Vortex body504includes a multiplicity of holes508bored into body504at an angle α (see, e.g.FIG. 10). Holes508may be bored in from the top side503of body504.

Base502may also include a means to hold an electrode62(FIG. 1). For example, in the exemplary embodiment threads520are bored into body504and/or extension506. These threads then line up with corresponding threads on an end of electrode62. In other embodiments, the means used to hold the electrode can take any number of forms. For example, connecting electrode62to base502could be accomplished using mating portions of electrode and base material such as slots and pin type connections, electrode62could be molded into base502, could have a projection having threads on base502and a mating hole(s) having threads in electrode62, electrode62and base502could be connected by frictional connectors, by fasteners, or by any other means.

Connecting electrode62directly to base502(rather than indirectly through a threaded ring attached to base502) allows stricter tolerances to be achieved for vortex generator500. Further, it may tend to avoid the problem of prior systems where the material used to connect a metal ring to the base would become worn over time due to electrical leaks and/or discharges.

Base502may also includes a central passage514. Electrical connectors can extend from electrode62through passage514to connect electrode62to a power supply. For example, a carbon brush assembly32(e.g. an assembly comprising a brush and a metal contact piece connected by a wire, the brush and the contact piece under tension of a spring) may extend from a depression in electrode62through passage514. As another example, electrode62may include wires, rods, or another electrically conductive portion that extends through passage514.

Referring toFIGS. 8-12an exemplary vortex generator600is formed from a ceramic base602. Base602may be cylindrical or may take some other shape. Base602includes a vortex body604and an extension606. Vortex generator600also includes a lip616that extends on the opposite side of body604than extension606. Vortex body604includes a multiplicity of holes608bored into body604at an angle α. When holes608are bored in from the bottom601of vortex generator600, lip616may include markings607caused by the drill used to bore holes608at angle α from bottom601rather than the top603.

Base602may also include a means to hold an electrode62(FIG. 1). For example, in the exemplary embodiment threads620are bored into body604. These threads then line up with corresponding threads on an end of electrode62. In other embodiments, the means used to hold the electrode can take any number of forms, such as those discussed above with respect toFIGS. 6 and 7.

Connecting electrode62directly to base602may have advantages similar to those discussed above forFIGS. 6 and 7for this feature.

Base602may also includes a central passage514. Passage614is much wider than passage514(FIG. 6). Passage614is about as wide as vortex body604. Electrical connectors can extend from electrode62through passage614to connect electrode62to a power supply.

While holes508are outside of passage514in vortex generator500(FIG. 6), holes608are located within passage614in vortex generator600, such that working gas will pass through passage614prior to passing through holes608.

Referring toFIGS. 6-12, vortex generators500and600may be formed by any number of methods and from any number of materials. In many embodiments it may be preferable to form vortex generator500,600from a non-conductive material such as a non-conductive ceramic. The non-conductive ceramic may be formed from a material such as aluminum oxide. This may be desirable to avoid spreading electrical current from electrode62to vortex generator500,600and/or to further distance the high voltage potential from the ground potential.

In one embodiment, a ceramic material is formed (e.g. molded) in a shape of base502,602. Holes508,608and passage514,614are then formed (e.g. with a drill/bore) in base502,602. In other embodiments, holes508,608and/or passage514,614may be formed as part of the step of forming base502,602. Next, the means for holding the electrode (e.g. threads520,620) are formed in base502,602. Once the structures are formed in base502,602, the ceramic base is cured to harden vortex generator500,600. The hardened vortex generator500,600may then be placed into a plasma generator12.

In many embodiments (such as that illustrated inFIG. 1) working gas passes from a top side510,610of generator500,600through holes508,608to a bottom side512,612of vortex generator500,600. Bottom side512,612may open up to a channel80(FIG. 1) in which plasma is generated. Placing the holes at an angle may tend to cause the working gas to flow through channel80in a swirling/vortex path. Thus, holes508,608may be referred to as an integral part of a swirl system. In some embodiments, vortex generators500,600may comprise at least 2 holes508,608and/or up to 20 holes508,608. According to some of these embodiments, vortex generators500,600comprise at least 4 or at least 6 holes and/or up to 15 holes or up to 10 holes.

While holes508,608can be formed at any angle α, in some embodiments holes508,608are formed at an angle α of at least about 30 degrees and/or up to about 60 degrees from a plane that extends perpendicular to a line that bisects the electrode carried by the vortex generator (see, e.g. line66ofFIG. 1), perpendicular to an axis526,626of vortex generator500,600, and/or parallel to a plane540,640of body504,604on the top side510,610or bottom side512,612of body504,604. In some embodiments, holes508,608may be formed at an angle of about 45 degrees.

Vortex generators500and600may be used in any number of different types of plasma generators. For example, these vortex generators can be used in moving plasma generators such as that illustrated inFIG. 1. However, vortex generators500and600may also be included in the prior plasma generators such as stationary plasma generators. In some embodiments having moving generators it may be preferable to use a vortex generator500having a small passage514to hold a brush and/or having a projection506around which other components (e.g. an O-ring) can pass.

Referring toFIGS. 1 and 5, an apparatus10for plasma treating a surface includes a plasma generator12and an actuator14. Plasma generator12is configured to generate a plasma output, such as a plasma stream. Actuator14is configured to move plasma generator12. Actuator14could be configured to continuously move plasma generator12or may be configured to intermittently move plasma generator12, which could allow plasma generator12to treat a larger width of a surface to be treated than the width of a plasma stream generated by plasma generator12.

In many embodiments, this movement may comprise a back and forth movement along a path P. For example, plasma generator12may be constrained to travel along a path P (e.g. a straight path P). Actuator14may be configured to continuously move plasma generator12back and forth along path P in a reciprocating motion. In this example, actuator14may be configured to move plasma generator12along path P in a first direction D1and then back along path P in the opposite direction D2. While a straight path is illustrated, other paths are possible. For example, path P could be a curved path, an ovular path, a path not having a defined shape, etc. In some embodiments, actuator14is used to move plasma generator12back and forth along path P by initiating movement in one direction and then allowing some other force (e.g. gravity) to move plasma generator12in the other direction.

Path P may be defined by a track22, and actuator14may be configured to move plasma generator12along track22. Track22is illustrated as a linear track. However, track22need not be linear. In some embodiments track22may be a curved track, may define a path P that does not conform to a standard shape, etc. Track22may include a linear bearing to allow plasma generator12to travel smoothly across track22. Track22is coupled to track plate28which extends along one side of a stationary portion13of apparatus10.

Plasma generator12includes a member20configured to cooperate with track22such that plasma generator12is at least partially constrained by track22. In some embodiments, this may comprise a bearing cartridge that projects around raised track22.

A corresponding track22′ (FIG. 2) and track cooperating member20′ (FIG. 2) are located on the opposite side of plasma generator12, parallel to track22and track cooperating member20. Plasma generator12is held between track22and track22′ by track cooperating member20and track cooperating member20′.

While track22is shown as a raised track surrounded by bearing cartridge20such that bearing cartridge20slides along track22, track22and track cooperating member20may take any number of other forms. For instance, track22may be formed as a groove or slot and track cooperating member20may be formed as a projection that mates with the slot or groove. Further, while track22is shown as a singular member, track22could be formed from a plurality of pieces. Further, track22could be have a complicated shape or pattern.

In other embodiments, track22and cooperating member20might be excluded. For example, plasma generator12may be rigidly coupled to a device that is configured to move in a defined path without using a track.

Plasma generator12may include an electrode62(such as a copper electrode or other metallic electrode) configured to strike and/or maintain an electrical arc. Electrode62may be coupled to a high voltage source. In one embodiment, electrode62is coupled to brush32(such as a carbon brush). Brush32may be connected to wire86which may be connected to a contact surface82. Surface82may extend through a bore in electrode62and make contact with electrode62. A tension member84such as a spring82may extend from surface82and/or electrode62to brush32to apply force to brush32.

The force applied to brush32helps maintain contact between brush32and a contact bar38, which is mounted to main block26in a stationary portion13of apparatus10via connector42. For example, the force may be configured to push brush32against contact bar38.

Contact bar38is connected to a (high) voltage source such as a high voltage cable extending through end cap34. As plasma generator12moves along a path, brush32is configured to maintain contact with contact bar38such that electrode62may continuously or intermittently be provided with electrical current. Contact bar38may be formed from a piece of stainless steel or other at least partially conductive material.

Body70and nozzle64of plasma generator12are connected to ground and can be used as a counter electrode to electrode62. In particular, brush24(which may be constructed similarly to brush32) is connected to main plate30(which may comprise an aluminum sheet) which is connected to ground. Force is applied to brush24by a tension member to maintain contact between brush24and conductive body71. Body71holds conductive body70using notches78. A conductive nozzle64is then screwed into body70. While shown as multiple pieces, body70, body71, and nozzle64could be a unitary piece or some other combination of pieces. Further, these pieces may be connected in any number of manners. Further, insulation may be included on the interior and/or exterior surfaces of the counter electrode system (64,70,71) of plasma generator12. In operation, brush24sweeps against body71maintaining a connection to ground as plasma generator12moves through its path.

Plasma is generated by plasma generator12when a working gas passes around an arc that is created between electrode62and a counter electrode such as nozzle64and/or body70.

In some embodiments (e.g. ones where no insulation is used) an arc might be struck between electrode62and body70. The arc may then travel down body70to nozzle64, possibly ending near mouth68.

The working gas (e.g. air) may be introduced through end cap34in stationary body13. The working gas then passes through spaces102,104(FIG. 2) around contact bar38before reaching vortex generator36, described in more detail with respect toFIGS. 5-6, below. The system may be configured such that the working gas passes through vortex generator36which is configured to cause the gas to take a non-straight path (e.g. a path that swirls through channel80). The working gas then passes around electrode62in channel80. The combination of the electric arc generated by electrode62and the working gas tend to create plasma. The plasma that is generated flows through an output port defined by mouth68of nozzle64. The stream of plasma that flows through mouth68can be used to treat a surface of a material or object that is placed near mouth68.

In many embodiments, plasma generator12is assembled by screwing nozzle64into threads90of body70. Likewise, electrode62is screwed into threads of vortex generator36. Vortex generator36(including electrode62) is then placed into body70, resting on shoulder88of body70. A compressible material76(e.g. on O-ring) is placed over and around vortex generator36and/or electrode62. Compressible material76maintains pressure against vortex generator36and holds vortex generator36in place against shoulder88. Compressible material76may also be configured to make up for variations in manufacturing of the components of plasma generator12.

Referring to actuator14, any number of types of actuators may be used for actuator14. For example, actuator14may be based on a mechanical system, a system of magnets (e.g. electromagnets), a hydraulic-based system, may utilize compressed air, may utilize a motor and pulleys, may use a solenoid, etc. Actuator14may be an electric actuator (i.e. powered by electricity).

In the illustrated example, actuator14is an electrical actuator including mechanical portions. Actuator14includes a motor50(e.g. an electric motor which may be a DC motor and may be a 24V DC motor). Motor50is mounted to plate48and is configured to rotate wheel/pulley52. Pulley52turns belt56which turns timing wheel/pulley58. Timing pulley58is connected to arm60at the pulley end74of arm60such that rotation of timing pulley58does not directly affect the rotational position of arm60. Arm60is connected to plasma generator12at a generator end72of arm60. As wheel58rotates, arm60moves towards and away from stationary portion13. This causes plasma generator12to move back and forth along track22following path P in direction D1(as end74is pulled away from stationary portion13) and then following path P in direction D2(as end74is pushed towards stationary portion13). Actuator14may contain other components to help ensure smooth operation, such as bearings46around a shaft of pulley58, a spacer54(e.g. aluminum spacer), etc.

Referring back to plasma generator12, in the illustrated embodiment, mouth68is arranged such that a line66that bisects electrode62also bisects mouth68. Further, the path defined by mouth68is parallel to line66. Other variations are possible. Mouth68may be offset from line66. For instance, mouth68may be placed over to the side of nozzle64and/or electrode62may be tilted. Further, mouth68may be at an angle with respect to line66. Mouth68may be at an acute angle with respect to line66, may be perpendicular to line66, etc.

The distance H between the end of the electrode62and the bottom of plasma generator12may be set as needed. In some embodiments, distance H may be at least about 20 mm or at least about 30 mm. In some of these embodiments, distance H may be at least about 40 mm. In some embodiments, distance H may be up to about 100 mm or up to about 80 mm. In some of these embodiments, distance H may be up to about 70 mm or up to about 60 mm.

The width W of channel80defined by body70may also be set as needed. In some embodiments, width W is at least about 10 mm or at least about 20 mm. According to some of these embodiments, width W is at least about 25 or at least about 30 mm. According to some embodiments, width W is up to about 60 mm or up to about 50 mm. According to some of these embodiments, width W is up to about 40 mm or up to about 35 mm.

The ratio between distance H and width W may also be varied. In some embodiments, the distance H is no more than 2 times width W. In some of these embodiments, distance H is no more than 1.9 or no more than 1.7 times width W. In some embodiments, distance H is at least as large as width W. In some of these embodiments, distance H is at least 1.1 or at least 1.3 times as large as width W. According to some embodiments, distance H is about 1.5 times the size of width W.

Referring toFIG. 2, a plasma generator12may be moved from a first extended position A to a second extended position C, passing through intermediate position B. Plasma generator12may then be moved back towards extended position A through intermediate position B.

As plasma generator12moves through positions A, B, C a relative position between main block26(of portion13) and plasma generator carriage100changes. As discussed above, brush24(carrying ground potential), tracks22,22′ (in the exemplary dual track system), track plates28,28′, contact bar38, and end cap34(FIG. 1) are connected to main block26. Thus, a relative position between these components and the components carried by plasma generator carriage100also change. Components of plasma generator carriage100which have their relative position changed with respect to these components can include vortex generator36including electrode62(FIG. 1), brush32(configured to provide high voltage), body70(FIG. 1), nozzle64(FIG. 1), and track cooperating members20,20′ (e.g. bearings).

As can be seen inFIG. 2, a position of brush32with respect to contact bar38changes as plasma generator12is moved along track22. Brush32is configured to brush against and maintain contact with contact bar38such that current can be transferred through bar38to electrode62(FIG. 1).

FIG. 3is a single cross-sectional view of plasma generator12in three different positions—positions A, B, and C. The changes in positions of the various components of plasma generator12between positions A, B, and C can be seen by noting the positions of the same numbered component followed by the position letter. For example,62A points to the position of electrode62in position A,62B points to the position of electrode62in position B, and62C points to the position of electrode62in position C.

Referring toFIG. 3, plasma generator12may be used to treat a surface204of an object200. Plasma generator12may be used to generate a stream of plasma202. Each stream of plasma202treats a portion T of surface204. Plasma generator12may be configured such that plasma stream202is output generally parallel to line66. In each position, plasma stream202can only treat a limited area of surface204. However, plasma generator12can be moved to provide treatment to a larger area of surface204. Thus, plasma stream202A will treat portion TA, plasma stream202B will treat portion TB, and plasma stream202C will treat portion TC. The combination of portions TA, TB, and TCcombine to treat an area of surface204greater than the area treated by a single plasma stream202. Plasma generator12may be configured to generate plasma streams202in additional positions such that surface204is also treated at portions TDand TE. In this manner, an entirety of surface204between two points (defined by the end positions of TAand TC) can be treated by plasma generator12. In many embodiments, plasma generator12will travel continuously through a multiplicity of positions between left position A and right position C such that plasma stream202is continuously provided to surface204between portion TAand portion TC. In addition to movement in directions D1and D2(FIG. 1), a relative position between object200and plasma generator12can be changed in other directions as well to treat a larger amount of surface204. For example, object200may be carried on a conveyor (not illustrated) past plasma generator12. As another example, plasma generator may be moved in a third direction (not illustrated) perpendicular to direction D1, such as by means of a robotic arm or along a second track, possibly using a second actuator. Any number of alternate arrangements can be used as well.

In some embodiments, the width of an individual area of a portion T treatable by a plasma generator may be at least about 0.1 inches and/or up to about 2 inches when surface204is 1 inch away from mouth68(FIG. 1). According to some of these embodiments, the width of an individual area is at least about 0.2 inches or 0.3 inches and/or up to about 1 inch or 0.6 inches.

Referring toFIG. 4, a system for plasma treating an object includes a processing circuit314. Processing circuit314can be configured to control actuator14, which in turn controls movement of plasma generator12(FIG. 1). Processing circuit314may be configured to control whether actuator14operates, a direction in which actuator14moves plasma generator12, or any other function of actuator14.

Processing circuit314can also be configured to control power supply circuit312which provides high voltage power to plasma generator12. By controlling power supply circuit312, processing circuit314can be configured to control the generation of a plasma stream202(FIG. 3) from plasma generator12.

Processing circuit314may also be configured to control a working gas control circuit318. Working gas control circuit controls the influx of a working gas to plasma generator12. Working gas control circuit.318may be configured to control an air compressor such that compressed air flows into plasma-generator12. Working gas control circuit and/or processing circuit314may operate in response to an air flow sensor which monitors parameters relating to the working gas, such as a quality/purity of the working gas.

Processing circuit314may also be configured to control a plasma generator control assembly316, such as a robotic arm on which the plasma generator is located, which is configured to control a position of plasma generator12an/or apparatus10.

Processing circuit314may include working gas control circuit318, power supply circuit312, plasma control assembly316, and actuator14, may share circuit components with these circuits, or may be separate from these components. Processing circuit314can include various types of processing circuitry, digital and/or analog, and may include a microprocessor, microcontroller, application-specific integrated circuit (ASIC), or other circuitry configured to perform various input/output, control, analysis, and other functions to be described herein. Processing circuit314may be configured to digitize data, to filter data, to analyze data, to combine data, to output command signals, and/or to process data in some other manner. Processing circuit314may also include a memory that stores data. Processing circuit314could be composed of a plurality of separate circuits and discrete circuit elements. In some embodiments, processing circuit314will essentially comprise solid state electronic components such as a microprocessor/microcontroller.

Processing circuit314may also be coupled to processing circuit306. Processing circuits314and306may be a common circuit, or may be composed of separate circuits. If separate circuits, processing circuits314and306may be directly connected by a communication line310, may be indirectly coupled by way of a network304or a separate control circuit.

Processing circuit306may be configured to receive user inputs from a user input device302. Processing circuit306may also be configured to control a material control assembly308. Material control assembly308is configured to control a position of an object by moving the object. For example, material control assembly308may comprise one or more conveyors configured to convey objects in a direction transverse to a direction that plasma generator12is moved by actuator14. Material control assembly308could also include a robotic arm configured to move the object. Material control assembly308could be configured to move the object in a plurality of directions with respect to plasma generator12.

Processing circuits306,314may be configured to control an assembly-line based on data received about the plasma treatment of an object. For example, processing circuits306,314may be configured to stop a conveyor assembly308if treatment is compromised.

Referring back toFIG. 5, a system may be constructed according to the embodiment ofFIG. 1as shown in the exploded view ofFIG. 5. Contact bar38may be connected to main block26by a set screw406. Brush assembly24may extend through space422in main block26. Brush assembly24may include a carbon brush424that is connected to a contact428by a wire (not illustrated). A tension member426such as a spring may extend between brush424and contact428.

Contact428is connected to ground wire416while contact bar38is connected to high voltage wire418. Ground wire416and high voltage wire418are carried by a common high voltage cable assembly410. Cable assembly410may also include gas supply tube414(e.g. an air supply tube) and/or a portion412of a pressure sensor, such as a differential pressure tube.

Motor50is connected to motor plate402. Wheel58is also connected to motor plate402. Wheel58is connected to shaft408around which bearings46a,46bare mounted. Spacers404help maintain space between motor plate402and main plate30.

EXEMPLARY EMBODIMENTS

One embodiment is directed to a device for plasma treating a surface. The device includes a plasma generator configured to provide a plasma treatment to a surface, and an actuator configured to provide a reciprocating motion to the plasma generator.

Another embodiment is directed to a device for plasma treating a surface. The device includes a plasma generator configured to provide a plasma treatment to a surface, the plasma generator configured to generate a plasma stream capable of treating an area of the surface of a first size. The device also includes a track, and an actuator configured to move the plasma generator along the track such that the plasma generator is configured to treat an area of the surface that is larger in size than the first size. The track may be a linear track.

Another embodiment is directed to a device for plasma treating a surface. The device comprises a plasma generator configured to provide a plasma treatment to a surface and an actuator configured to move the plasma generator in a first direction along a path and in a second direction substantially along the path. The second direction is different than the first direction.

Another embodiment is directed to a device for plasma treating a surface. The device includes a plasma generator configured to provide a plasma treatment to a surface, and an actuator configured to provide a reciprocating motion to the plasma generator.

Another embodiment is directed to a device for plasma treating a surface. The device includes a plasma generator configured to provide a plasma treatment to a surface, and an electrical actuator configured to move the plasma generator back and forth along a substantially linear path.

Another embodiment is directed to a device for plasma treating a surface the device includes a plasma generator configured to provide a plasma treatment to a surface. The plasma generator comprises a mouth through which plasma is provided from the plasma generator. The mouth is offset from the center of the plasma generator. The device may also include an actuator configured to move (e.g. rotate) the mouth.

Another embodiment provides a plasma generator and a means for treating an area of a surface that is larger in size than a size of a plasma output of the plasma generator.

Another embodiment is directed to a device for plasma treating a surface. The device includes a plasma generator configured to provide a plasma treatment to a surface, and an electrical actuator configured to move the plasma generator from a first position to a second position via an intermediate position. The actuator is then configured to move the actuator back to the first position via the intermediate position.

Another embodiment is directed to a device for plasma treating a surface. The device includes a plasma generator configured to provide a plasma treatment to a surface, and an electrical actuator configured to move the surface to be treated in a plurality of directions with respect to the plasma generator.

In the devices according to any of the embodiments discussed above, the plasma generator may include one or more of an electrode configured to provide an electrical arc, a counter electrode for providing the electrical arc, an input for a working gas configured to receive a working gas such that the electrical arc and the working gas interact to form plasma; a nozzle configured to output a plasma stream, and a mouth through which plasma can exit. The plasma generator may be configured to continuously provide a plasma output as it is moved by the actuator.

The vortex generator may comprise a unitary piece having angled holes configured such that a working gas will travel through the holes, and threads for holding an electrode. The vortex generator may be formed of a non-conductive material such as ceramic. The vortex generator may be configured such that a brush assembly can extend from an electrode (potentially held by the vortex generator) through the vortex generator.

The brush assembly may be configured such that the electrode is provided with electrical current while the plasma generator is moved in the manner discussed in the embodiments above.

The electrode may be enclosed in a chamber and the walls of the chamber may serve as the counter electrode. The chamber may be defined by a body and by a nozzle separate from the body.

In the devices according to any of the embodiments discussed above, the actuator may include a motor configured to move the plasma generator as discussed in any of the embodiments. The motor may be configured to drive a wheel. The wheel may be linked to the plasma generator by an arm. The actuator may be configured to move all of the plasma generator or only a portion of the plasma generator. The actuator may be configured to move the plasma generator back and forth in the manner described in the embodiment.

The device according to any of the embodiments discussed above may include a plurality of plasma generators configured to provide a plasma treatment to the surface. The plurality of plasma generators may be linked or may be separate. The plasma generators may be arranged in a line, may be staggered, may form a regular, repeating pattern, or may take some other configuration that is not any of these configurations.

The devices discussed with respect to any of the embodiments above may include a first portion configured to receive a power supply, and a second portion comprising an electrode and a plasma output. The actuator may be configured to move the second portion as discussed in the embodiment. Movement in the manner discussed in the embodiment may cause the first portion and the second portion to change their relative positions. A track may be connected to the first portion. The first portion may be configured to be a stationary portion.

The plasma generators discussed above may include all-metal treating heads.

A system for treating a surface may include a device constructed according to one or more of the embodiments discussed above. The system may include a cabinet. The cabinet may be one or more of welded and powder-coated. The cabinet may contain a generator, a control system, a high-voltage transformer, the device constructed according to one of the above-mentioned embodiments, and/or an air-supply system that provides a gas to the plasma generator.

Another embodiment is directed to a method for treating vehicle parts. The method includes providing a part of a vehicle, applying plasma to a surface of the vehicle part, and installing the car part in a vehicle. Applying plasma may comprise applying plasma using a movable plasma generator. The movable plasma generator may be constructed according to one or more of the embodiments discussed above. The vehicle part may include an interior panel and/or a headlight shielding. The vehicle part may be a plastic part.

Another embodiment is directed to a method of cleaning a cell phone component. The method includes providing a component of a cell phone, and applying plasma to a surface of the component. The component may then be used to form a cell phone. Applying plasma may comprise applying the plasma using a high pressure working gas. This may allow particles that have been de-charged by the plasma stream to be blown away by the high pressure of the plasma stream.

Another embodiment is directed to a method of treating an area of a surface that is greater than an area of a plasma stream. The method includes generating a plasma output, applying the plasma output to the surface to be treated. Applying the plasma output includes reciprocating the plasma output. The output may be reciprocated along a path, which may be a linear path. Reciprocating the plasma output may comprise reciprocating a plasma generator, which may include reciprocating a portion of the plasma generator (e.g. the nozzle) or may include reciprocating the entire plasma generator. The plasma generator (and corresponding device) may be constructed according to any of the embodiments discussed above. The plasma generator is preferably reciprocated while the plasma generator is providing a plasma output. The plasma output is preferably continuous throughout the path of reciprocation.

Another embodiment is directed to a method for plasma treating a surface that is larger than a width of a plasma beam. The method includes generating a plasma output from a plasma generator and applying the plasma output to the surface to be treated. Applying the plasma output includes moving the plasma generator along a track. The track may be a linear track. Moving the plasma generator along the track may include moving a portion of the plasma generator (e.g. the nozzle) along the track or may include moving the entire plasma generator along the track. The plasma generator (and corresponding device) may be constructed according to any of the embodiments discussed above. The plasma generator is preferably moved along the track while the plasma generator is providing a plasma output. The plasma output is preferably continuous throughout the path of travel along the track. The plasma generator may be directly connected to the track along which it is moved, or may be connected to another body, which other body is moved along the track.

Another embodiment is directed to a method for plasma treating a surface that is larger than a width of a plasma beam. The method includes generating a plasma output, applying the plasma output to a surface to be treated by moving the plasma output in a first direction along a path, and applying the plasma output to a surface to be treated by moving the plasma output in a second direction different than the first direction, movement in the second direction substantially being movement along the same path as movement in the first direction.

The path may be a linear path. Moving the plasma generator along the path may include moving a portion of the plasma generator (e.g. the nozzle) along the path or may include moving the entire plasma generator along the path. The plasma generator (and corresponding device) may be constructed according to any of the embodiments discussed above. The plasma generator is preferably moved along the path while the plasma generator is providing a plasma output. The plasma output is preferably continuous throughout the course of travel along the path.

According to any of the above-mentioned methods, the movement may be accomplished using an actuator (e.g. an electric actuator) as discussed above. Movement may be back and forth. Movement may be continuous. Movement may be controlled by a processing circuit, and/or timed with movement of and/or presence of an object to be treated—which information may be supplied to the processing circuit (e.g. from a sensor or from another circuit which may be monitored by the processing circuit). The methods may include stopping movement of the plasma output based on the occurrence of an event.

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator includes a base material. The vortex generator is configured to generate a vortex of working gas in the plasma generator. The base material is configured to directly hold the electrode.

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator includes a base material that defines an attachment surface. The attachment surface is configured to attach to a surface of the electrode. The vortex generator is configured to generate a vortex of working gas in the plasma generator. The base material may be configured such that the electrode is releasably attached or may be configured such that the electrode is fixedly attached.

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator comprises a non-conductive base material. Threads are integrally formed in the base material. A plurality of holes are also formed in the base material. The plurality of holes are configured to receive a working gas and to generate a vortex of working gas in the plasma generator. A second hole is also formed in the base material. The second hole can receive a conductor which may attach to the electrode to supply power to the electrode.

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator comprises a base material defining threads. The vortex generator is configured to generate a vortex of working gas in the plasma generator using the base material.

Another embodiment is directed to a vortex generator for generating a vortex in and holding an electrode of a plasma generator. The vortex generator comprises threads integrally formed in a base material. The vortex generator is configured to generate a vortex of working gas in the plasma generator.

Another embodiment is directed to a plasma generator. The plasma generator comprises a working gas inlet for receiving a working gas, a chamber in which plasma is generated, an electrode configured to generate an electrical arc, and a vortex generator arranged such that at least some of the working gas passes from the working gas inlet through the vortex generator before passing through the chamber. The vortex generator includes a base material having a plurality of holes through which working gas can pass, the holes being arranged to generate a vortex in the chamber. The base material is configured to hold the electrode.

Another embodiment provides a plasma generator. The plasma generator comprises a means for generating an electrical arc, an inlet for a gas, and a means for generating a vortex of the gas and for holding an electrode in a one-piece frame. The generator is configured such that the gas and the electrical arc interact to form plasma.

Another embodiment is directed to a plasma generator. The plasma generator comprises a gas inlet for receiving a gas, an electrode configured to generate an electrical arc, a chamber in which plasma is generated from the interaction of the gas and the electrical arc; and a vortex generator arranged such that at least some of the gas passes from the gas inlet through the vortex generator before passing through the chamber. The vortex generator is configured to swirl the gas and maintain a position of the electrode using a common body.

Another embodiment is directed to a method for forming a vortex generator. The method comprises providing a body, forming a vortex system in the body, and connecting the electrode to the body. The method may also include forming a means to connect the electrode to the body in the body. The means formed in the body could include threads.

The vortex generators and plasma generators including the vortex generators may include any combination of the above described features. The vortex generators may be used in stationary plasma generators or may be used in moving plasma generators. The vortex generators can include one or more (or none) of other features such as the following. The vortex generator may include a hole in the base material configured to receive a conductor to supply power to the electrode. The hole may be configured such that the electrode can be attached on a first side of the base material and the conductor extends through a second side of the base material. The vortex generator may be configured such that a working gas passes through the hole receiving the conductor before passing through the plurality holes configured to generate the vortex in the chamber of the plasma generator. The base material of the vortex generator may include a body and/or an extension. The plurality of holes in the base material configured to receive a working gas may be formed in the body. The hole configured to receive the conductor may extend through the body and/or the extension. The base material may further include a lip. The vortex generator may be configured such that the electrode is at least partially recessed in the lip. Threads is the base material may be configured to mate with corresponding threads of the electrode. The base material may be composed essentially of non-conductive material such as a non-conductive ceramic. And any number of additional features can be included in the vortex generator, including those features discussed above (particularly with reference toFIGS. 6-12).

Any of the above-described illustrative methods, devices, and systems can be combined according to other embodiments. For example the method for treating a vehicle part may include treating the vehicle part using a reciprocating plasma generator. The reciprocating plasma generator could include a vortex generator formed as described in any of the illustrative embodiments.

In constructing the claims directed to these and other embodiments, the claims should be read in light of the following:

Reference to “a” or “at least one” in a claim reciting “comprising” as the transitional language is a reference to an embodiment that includes one or more of the component recited unless limited by other specific terms such as “a single”, “a unitary”, etc.

Reference to “and/or” in the claims should be given its ordinary meaning which is the use of one or more of the elements recited in the “and/or phrase.” In other words, it covers the use of just one of the elements recited in the “and/or phrase”, and also covers use of more than one of the elements recited in the “and/or phrase.” The same meaning should be given to a claim reciting “at least one of ______, ______, and ______.”

The invention has been described with reference to various specific and illustrative embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope of the invention. For example, while much of the discussion has related to loaves of bread, other dough-based baking products (particularly products which are used to define the three-dimensional shape of the product—such as cake or brownie pans) can be formed according to the disclosure of the present application.

For example, the brushes24,32can be arranged in any manner on any portion of the system. Alternatively, other structures (such as permanently fixed wires which extend across a gap between moving and non-moving portions) may be used in place of brushes24,32.

As another example, in the illustrated embodiment, a single contact bar is configured to extend across the length of the path P (FIG. 1) of plasma generator12. In other embodiments, more than one contact bar may be used. In most embodiments, at least one contact bar will be used. In the illustrated embodiment, brush32maintains electrical contact with contact bar38for the entire length of travel of plasma generator12. In some embodiments, there may be gaps at the end positions, middle positions, or some combination of positions where electrical power is not provided—such as to avoid providing plasma treatment to a specific portion of the surface of the object being treated.

As another example, plasma generator12need not be placed on a fixed track22in some embodiments, may be placed on a multi-option track that allows customization, may be placed on a single part or multi-part track (e.g. a 4 or more piece track), etc.

As another example, vortex generator36can take a standard form according to some embodiments, the holes408of vortex generator36can receive a working gas from a common working gas supply or can receive air from multiple (including individual) working gas supplies. In some embodiments, vortex generator36can be excluded and replaced by components which achieve the same effect such as air pipes arranged at an angle with respect to the direction between electrode62and mouth68. In still other embodiments, plasma generator12may not have a swirl system for the working gas such that the working gas passes through plasma generator12in a straight direction.

While shown as stationary, portion13could be configured to move with portion100being stationary. In other embodiments, both portions13and100could be configured to move or be movable.

While movement of plasma generator12is illustrated in one dimension, movement may be made in more than one dimension. Also, while linear reciprocation is the primary type of reciprocation of interest as shown inFIGS. 2 and 3, other types of reciprocation, such as angular reciprocation (i.e. reciprocating about a pivot point) are also within the scope of the claims unless stated otherwise.

Various other modifications, changes, exclusions, and inclusions can be made while staying within the scope of the claims as recited. For example, the teachings herein can be applied to other treatment systems, such as other electrostatic discharge treatment systems, flame treatment systems, etc.