Electrostatic paint spray system

Claim 2

In an electrostatic spray coating system wherein high velocity atomizing air is employed to generate a spray of atomized liquid coating material which is electrostatically attracted toward and deposited upon a grounded article while still in a liquid state, means for selectively introducing such material into a stream of pressurized atomizing air, and an electrogasdynamic power generating means disposed integrally adjacent the locus of atomization and operatively responsive to at least a portion of the flow of said seeded atomizing air therethrough at a velocity in the vicinity of the sonic velocity and having a voltage and current output of a magnitude dependent upon the magnitude of the delivery rate of said seeded atomizing air for effecting proportional variations in the magnitude of the average depositing field strength of an electrostatic depositing field engendered thereby.

Claim 3

In an electrostatic spray coating system wherein high velocity atomizing air is employed to generate a spray of atomized liquid coating material which is electrostatically attracted toward and deposited upon a grounded article while still in a liquid state, means for selectively introducing seed material into a stream of pressurized atomizing air, and an electrogasdynamic power generating means disposed integrally adjacent the locus of atomization and operatively responsive to at least a portion of the flow of said seeded atomizing air therethrough having a voltage and current output of a magnitude dependent upon the magnitude of the delivery rate of said seeded atomizing air for effecting proportional variations in the magnitude of the average depositing field strength of an electrostatic depositing field engendered thereby, said electrogasdynamic power generating means comprising an elongate channel having an attractor electrode means shaped to define a passage for the flow of said seeded atomizing air therethrough, a converging conduit section disposed on the upstream side of said attractor electrode to accelerate the flow of seeded atomizing air thereto, ionizing electrode means positioned within said conduit section to provide a discharge current flow path to said attractor electrode and an elongate channel section disposed on The downstream side of said attractor electrode means for conveying said atomizing air stream therefrom at an average speed in the vicinity of the sonic velocity.

Claim 4

In an electrostatic spray coating system wherein high velocity atomizing air is employed to generate a spray of atomized liquid coating material which is electrostatically attracted toward and deposited upon a grounded article while still in a liquid state, means for selectively introducing seed material into a stream of pressurized atomizing air, and an electrogasdynamic power generating means disposed integrally adjacent the locus of atomization and operatively responsive to at least a portion of the flow of said seeded atomizing air therethrough having a voltage and current output of a magnitude dependent upon the magnitude of the delivery rate of said seeded atomizing air for effecting proportional variations in the magnitude of the average depositing field strength of an electrostatic depositing field engendered thereby, said electrogasdynamic power generating means comprising an elongate channel having an attractor electrode means shaped to define a passage for the flow of said seeded atomizing air therethrough, a converging conduit section disposed on the upstream side of said attractor electrode to accelerate the flow of seeded atomizing air thereto, ionizing electrode means positioned within said conduit section to provide a discharge current flow path to said attractor electrode and an elongate channel section disposed on The downstream side of said attractor electrode means for conveying said atomizing air stream therefrom at an average speed in the vicinity of the sonic velocity.

Claim 5

The combination as set forth in claim 2 wherein said converging conduit section is constituted by a plurality of coaxial bores of progressively decreasing internal diameter in the direction of air flow therethrough thereby presenting a plurality of annular shoulders in substantially perpendicular relation to the approaching air flow.

Claim 6

In an air atomized electrostatic spray coating device wherein a high velocity stream of seeded atomizing air is employed to generate a spray of atomized liquid coating material which is electrostatically attracted toward and deposited upon a grounded article while still in a liquid state, an electrogasdynamic power generating means disposed integrally adjacent the locus of atomization therein and operatively responsive to the flow of at least a portion of said stream of seeded atomizing air therethrough having a voltage and current output of a magnitude dependent upon the magnitude of the delivery rate of said first air stream to effect proportional variations in the magnitude of the average depositing field strength of an electrostatic depositing field engendered thereby; said electrogasdynamic power generating means comprising an elongate channel having an attractor electrode means shaped to define a passage for the flow of said seeded atomizing air therethrough, a converging conduit section disposed on the upstream side of said attractor electrode to accelerate the flow of seeded atomizing air thereto, ionizing electrode means positioned within said conduit section to provide a discharge current flow path to said attractor electrode and an elongate channel section disposed on the downstream side of said attractor electrode means for conveying said atomizing air stream therefrom at an average speed in the vicinity of the sonic velocity.

Claim 7

In an air atomized electrostatic spray coating device wherein a high velocity stream of seeded atomizing air is employed to generate a spray of atomized liquid coating material which is electrostatically attracted toward and deposited upon a grounded article while still in a liquid state, an electrogasdynamic power generating means disposed integrally adjacent the locus of atomization therein and operatively responsive to the flow of at least a portion of said stream of seeded atomizing air therethrough having a voltage and current output of a magnitude dependent upon the magnitude of the delivery rate of said first air stream to effect proportional variations in the magnitude of the average depositing field strength of an electrostatic depositing field engendered thereby; said electrogasdynamic power generating means comprising an elongate channel having an attractor electrode means shaped to define a passage for the flow of said seeded atomizing air therethrough, a converging conduit section disposed on the upstream side of said attractor electrode to accelerate the flow of seeded atomizing air thereto, ionizing electrode means positioned within said conduit section to provide a discharge current flow path to said attractor electrode and an elongate channel section disposed on the downstream side of said attractor electrode means for conveying said atomizing air stream therefrom at an average speed in the vicinity of the sonic velocity.

Claim 8

The combination as set forth in claim 2 wherein said ionizing electrode means and attractor electrode means are selectively electrically connected intermediate an excitation potential and ground.

Claim 9

In an electrostatic spray coating gun wherein an emitted spray of atomized liquid coating material is electrostatically attracted toward and deposited upon a grounded article while still in a liquid state, an insulating body member containing a cartridge receiving bore and having liquid coating material atomizing means disposed at one end thereof and a groundable conducting base member disposed at the other end thereof, an electrogasdynamic power generating cartridge member removably disposed within said cartridge receiving bore and operatively responsive to the flow of a stream of seeded air therethrough and having a voltage and current output of a magnitude dependent upon the volumetric magnitude of said seeded air stream therethrough to effect proportional variations in the magnitude of the average depositing field strength of an electrostatic depositing field engendered thereby, said electrogasdynamic power generating cartridge member comprising an elongate channel having an attractor electrode means shaped to define a passage for the flow of said seeded atomizing air therethrough, a converging conduit section disposed on the upstream side of said attractor electrode to accelerate the flow of seeded atomizing air thereto, ionizing electrode means positioned within said conduit section to provide a discharge current flow path to said attractor electrode and an elongate channel section disposed on the downstream side of said attractor electrode means for conveying said atomizing air stream therefrom at an average speed in the vicinity of the sonic velocity.

Claim 10

In an electrostatic spray coating gun wherein an emitted spray of atomized liquid coating material is electrostatically attracted toward and deposited upon a grounded article while still in a liquid state, an insulating body member containing a cartridge receiving bore and having liquid coating material atomizing means disposed at one end thereof and a groundable conducting base member disposed at the other end thereof, an electrogasdynamic power generating cartridge member removably disposed within said cartridge receiving bore and operatively responsive to the flow of a stream of seeded air therethrough and having a voltage and current output of a magnitude dependent upon the volumetric magnitude of said seeded air stream therethrough to effect proportional variations in the magnitude of the average depositing field strength of an electrostatic depositing field engendered thereby, said electrogasdynamic power generating cartridge member comprising an elongate channel having an attractor electrode means shaped to define a passage for the flow of said seeded atomizing air therethrough, a converging conduit section disposed on the upstream side of said attractor electrode to accelerate the flow of seeded atomizing air thereto, ionizing electrode means positioned within said conduit section to provide a discharge current flow path to said attractor electrode and an elongate channel section disposed on the downstream side of said attractor electrode means for conveying said atomizing air stream therefrom at an average speed in the vicinity of the sonic velocity.

Claim 11

The combination as set forth in claim 6 wherein said ionizing electrode means and attractor electrode means are selectively electrically connected intermediate an excitation potential and ground.

Claim 12

The combination as set forth in claim 6 wherein Said cartridge member includes a conducting sleeve member for mounting said ionizing electrode means in predetermined spatial relation with said attractor electrode means and for electrically connecting the latter with the groundable conducting base member of said gun when said cartridge is operatively disposed in said cartridge receiving bore.

Claim 13

The combination as set forth in claim 6 including a collector electrode element mounted in said body member and extending into said cartridge receiving bore in coaxial spaced relation with the end of said elongate channel member disposable therein.

Claim 14

The combination as set forth in claim 9 wherein said cartridge member includes a mounting sleeve adjacent said conduit section thereof threadedly engageable with a complemental coaxial bore surface in said groundable base member for fixedly locating said cartridge member in said cartridge receiving bore with said elongate channel member disposed in predetermined spaced relation with said collector electrode element.

Claim 15

The combination as set forth in claim 8 wherein said conducting sleeve member is threadedly engageable with a complemental coaxial bore surface in said groundable conducting base member for fixedly locating said cartridge member within said cartridge receiving bore in said body member.

Claim 16

The combination as set forth in claim 6 wherein said seeded air is introduced into said electrogasdynamic power generating cartridge member from a remotely located pressurized supply thereof through a hose means connected to said groundable base member and wherein said base member is connectable to ground through conducting means associated with said hose member.

Claim 17

The combination as set forth in claim 9 wherein said cartridge receiving bore is of greater internal diameter than the external diameter of the elongate channel section of the electrogasdynamic power generating cartridge member disposed therewithin for providing an annulus for an exiting flow of seeded air moving countercurrent to the flow through said cartridge member and in a direction away from said collector electrode element and toward said groundable base member.

Claim 18

The combination as set forth in claim 13 including valve means for directing the exiting flow of said air disposed remote from said collector electrode means and in close proximity to said groundable base member.

Claim 19

The combination as set forth in claim 6 wherein said seeded air, the excitation potential for maintaining a corona current flow intermediate said ionizing electrode means and said attractor electrode means, and a conductor for connecting said base member to ground are associated with a common conduit member connectable to said base member.

Claim 20

In an electrostatic spray coating gun wherein an emitted spray of atomized liquid coating material is electrostatically attracted toward and deposited upon a grounded article while still in a liquid state, an insulating body member containing a cartridge receiving bore and having liquid coating material atomizing means disposed at one end thereof and a groundable conducting base member disposed at the other end thereof, an electrogasdynamic power generating cartridge member removably disposed within said cartridge receiving bore and operatively responsive to the flow of a stream of seeded air therethrough and having a voltage and current output of a magnitude dependent upon the volumetric magnitude of said seeded air stream therethrough to effect proportional variations in the magnitude of the average depositing field strength of an electrostatic depositing field engendered thereby, a liquid coating material delivering bore disposed within said body member in fluid communication with said atomizing means disposed at the end thereof, an externally actuatable valve stem assembly displaceably mounted within said liquid delivering bore for regulating the flow of liquid therethrough to said atomizing means, said valve stem assembly including telescopic sleeve means Disposed within said bore to increase the length of available surface paths to ground from said liquid coating material disposed therein.

Claim 21

In an electrostatic spray coating gun wherein an emitted spray of atomized liquid coating material is electrostatically attracted toward and deposited upon a grounded article while still in a liquid state, an insulating body member containing a cartridge receiving bore and having liquid coating material atomizing means disposed at one end thereof and a groundable conducting base member disposed at the other end thereof, an electrogasdynamic power generating cartridge member removably disposed within said cartridge receiving bore and operatively responsive to the flow of a stream of seeded air therethrough and having a voltage and current output of a magnitude dependent upon the volumetric magnitude of said seeded air stream therethrough to effect proportional variations in the magnitude of the average depositing field strength of an electrostatic depositing field engendered thereby, a liquid coating material delivering bore disposed within said body member in fluid communication with said atomizing means disposed at the end thereof, an externally actuatable valve stem assembly displaceably mounted within said liquid delivering bore for regulating the flow of liquid therethrough to said atomizing means, said valve stem assembly including telescopic sleeve means Disposed within said bore to increase the length of available surface paths to ground from said liquid coating material disposed therein.

Claim 22

In a method of electrostatically depositing a coating material on an article wherein liquid coating material is emitted in an atomized spray pattern into an electrostatic depositing field by action of high velocity air delivered from a remote supply thereon in proximity to an electrostatically induced ionized atmosphere, the step of passing at least a portion of the air delivered from said remote supply through an electrogasdynamic power generator at an average speed in the vicinity of the sonic velocity to maintain said electrostatically induced ionized atmosphere and said depositing field at an average field strength of a magnitude proportional to the rate of flow of said air that interacts with said liquid coating material.

Claim 23

In a method of electrostatically depositing a coating material on an article wherein liquid coating material is emitted in an atomized spray pattern into an electrostatic depositing field by action of high velocity air delivered from a remote supply thereon in proximity to an electrostatically induced ionized atmosphere, the step of passing at least a portion of the air delivered from said remote supply through an electrogasdynamic power generator at an average speed in the vicinity of the sonic velocity to maintain said electrostatically induced ionized atmosphere and said depositing field at an average field strength of a magnitude proportional to the rate of flow of said air that interacts with said liquid coating material.

Claim 24

In a method for electrostatically depositing a coating meterial on an article wherein liquid coating material is emitted in an atomized spray pattern into an electrostatic depositing field by the action of high velocity air in proximity to an electrostatically induced ionized atmosphere the steps of, introducing seed material into said air at a location remote from the locus of atomization of said liquid coating material, passing at least a portion of said seeded air through an electrogasdynamic power generator at an average speed in the vicinity of the sonic velocity to maintain said electrostatically induced ionized atmosphere and said electrostatic depositing field at an average field strength of a magnitude proportional to the rate of flow of said air.

Claim 25

In a method for electrostatically depositing a coating meterial on an article wherein liquid coating material is emitted in an atomized spray pattern into an electrostatic depositing field by the action of high velocity air in proximity to an electrostatically induced ionized atmosphere the steps of, introducing seed material into said air at a location remote from the locus of atomization of said liquid coating material, passing at least a portion of said seeded air through an electrogasdynamic power generator at an average speed in the vicinity of the sonic velocity to maintain said electrostatically induced ionized atmosphere and said electrostatic depositing field at an average field strength of a magnitude proportional to the rate of flow of said air.