Electrostatic isolation apparatus and method

Claim 2

An isolator for an electrostatic coating system comprising: a housing; a receptacle, having an opening in an upper portion thereof and mounted in the housing, for electrostatic coating material which is at a first electrical potential; an outlet conduit communicating between the receptacle and the exterior of the housing for supplying electrostatic coating material from the receptacle for use by an electrostatic coating device; a nozzle chamber, for electrostatic coating material at a second electrical potential, mounted above the receptacle and having an aperture in a bottom portion thereof, to serve as a nozzle for dispensing electrostatic coating material; means for coupling electrostatic coating material to the nozzle chamber from an electrostatic coating material supply; means for mechanically vibrating the electrostatic coating material in the nozzle chamber to produce a pulsed jet droplet flow of electrostatic coating material in a relatively confined path from the aperture in the bottom portion of the nozzle chamber downwardly into the opening in the upper portion of the receptacle; and an electrostatic shield, at an electrical potential substantially closer to said second electrical potential than to said first electrical potential, mounted between the receptacle and the nozzle chamber to substantially electrically shield the nozzle chamber from electrical potentials below the shield including the electrical potential of the electrostatic coating material in the receptacle, the electrostatic shield having an aperture sized to permit the passage of the pulsed jet droplet flow of electrostatic coating material in a relatively confined path from the nozzle chamber to the receptacle.

Claim 3

The isolator of claim 1 in which the nozzle chamber is mounted within the housing above the receptacle.

Claim 4

The isolator of claim 2 in which the electrostatic shield is mounted in the housing between the receptacle and the nozzle chamber.

Claim 5

The isolator of claim 3 in which the second electrical potential of the electrostatic coating material in the nozzle chamber is a ground potential.

Claim 6

The isolator of claim 4 in which the electrostatic shield is at a ground potential.

Claim 7

The isolator of claim 5 in which the housing in the vicinity of the nozzle chamber, for electrostatic coating material at a ground potential, is electrically conductive and at a ground potential.

Claim 8

The isolator of claim 5 in which the housing is substantially electrically conductive and at a ground potential.

Claim 9

The isolator of claim 1 in which the second electrical potential of the electrostatic coating material in the nozzle chamber is a ground potential.

Claim 10

The isolator of claim 8 in which the electrostatic shield is at a ground potential.

Claim 11

The isolator of claim 1 in which the receptacle comprises a generally rounded exterior wall.

Claim 12

The isolator of claim 10 in which the receptacle further comprises a coating material cup mounted in the rounded exterior wall.

Claim 13

The isolator of claim 11 in which the receptacle further comprises a funnel having an angled sidewall beneath the opening in the upper portion of the receptacle for receiving said pulsed jet droplet flow.

Claim 14

The isolator of claim 11 in which the opening in the upper portion of the receptacle is smaller than the surface area of coating material in the cup.

Claim 15

The isolator of claim 1 in which the nozzle chamber, mounted above the receptacle, has an aperture in a bottom portion thereof which is a nozzle aperture.

Claim 16

The isolator of claim 14 in which the means for coupling the electrostatic coating material supply to the nozzle chamber comprises a bore in a wall of the nozzle chamber.

Claim 17

The isolator of claim 1 in which the means for mechanically vibrating the electrostatic coating material comprises means for producing oscillatory pressure changes at the aperture in the bottom portion of the nozzle chamber.

Claim 18

The isolator of claim 16 in which the means for mechanically vibrating the electrostatic coating material further comprises a diaphragm forming one wall of the nozzle chamber.

Claim 19

The isolator of claim 17 in which the means for mechanically vibrating the electrostatic coating material further comprises a piston attached to the diaphragm and movable within the nozzle chamber.

Claim 20

The isolator of claim 18 in which the nozzle chamber, mounted above the receptacle, has an aperture in a bottom portion thereof which is a nozzle aperture.

Claim 21

The isolator of claim 19 in which the means for coupling the electrostatic coating material supply to the nozzle chamber comprises a bore in a wall of the nozzle chamber.

Claim 22

The isolator of claim 20 in which the piston is reciprocable in the nozzle chamber and operable to cover and uncover the bore in the nozzle chamber.

Claim 23

The isolator of claim 1 in which the means for mechanically vibrating the electrostatic coating material in the nozzle chamber comprises a diaphragm forming a top wall of the nozzle chamber and a vibrator coupled to the diaphragm mounted above the nozzle chamber for driving the diaphragm to produce oscillatory pressure changes in the nozzle chamber.

Claim 24

The isolator of claim 22 which further comprises means for varying the frequency of vibration of the vibrator.

Claim 25

The isolator of claim 22 which further comprises means for varying the force applied to the membrane by the vibrator.

Claim 26

The isolator of claim 24 which further comprises means for varying the frequency of vibration of the diaphragm by the vibrator.

Claim 27

The isolator of claim 22 in which the nozzle chamber is mounted within the housing above the receptacle.

Claim 28

The isolator of claim 26 in which the second electrical potential of the electrostatic coating material in the nozzle chamber is a ground potential.

Claim 29

The isolator of claim 27 in which the housing further comprises a lid at the top of the housing, beneath which the vibrator and the nozzle chamber are mounted.

Claim 30

The isolator of claim 1 which further comprises means for sensing droplet separation in the pulsed jet droplet flow at a location between the receptacle and the nozzle chamber and means responsive to the sensed separation for controlling the means for mechanically vibrating the electrostatic coating material in the nozzle chamber.

Claim 31

The isolator of claim 29 in which the means for mechanically vibrating the electrostatic coating material in the nozzle chamber comprises a diaphragm forming a top wall of the nozzle chamber and a vibrator coupled to the diaphragm mounted above the nozzle chamber for driving the diaphragm to produce oscillatory pressure changes in the nozzle chamber.

Claim 32

The isolator of claim 30 which further comprises means for varying the force applied to the membrane by the vibrator.

Claim 33

The isolator of claim 31 which further comprises means for varying the frequency of vibration of the diaphragm by the vibrator.

Claim 34

The isolator of claim 32 in which the means for controlling the means for mechanically vibrating the electrostatic coating material in the nozzle chamber comprises means for controlling the frequency and force of vibration of the vibrator.

Claim 35

The isolator of claim 29 in which the means for sensing the droplet separation location comprises a photosensor arrangement positioned along the pulsed jet droplet flow path.

Claim 36

The isolator of claim 34 in which the photosensor arrangement comprises a light source directing light through the path of the pulsed jet droplet flow and a light sensitive device on an opposite side of the path for receiving light from the light source, interrupted by droplet flow in the path.

Claim 37

The isolator of claim 35 in which the light sensitive device produces an electrical signal indicative of the light received from the light source and further comprising means for controlling the frequency and force of the vibrator utilizing said electrical signal.

Claim 38

The isolator of claim 36 which further comprises a light-focusing lens positioned between the pulsed jet droplet flow path and the light sensitive device for focusing light upon the light sensitive device.

Claim 39

The isolator of claim 37 which further comprises means for defining a narrow slit transverse to the path of the pulsed jet droplet flow at a location between the flow path and the focusing lens.

Claim 40

The isolator of claim 1 which further comprises a coating material collection bowl mounted above the electrostatic shield and below the nozzle chamber, for collecting splattered coating material from the aperture in the bottom portion of the nozzle chamber, the bowl being apertured in line with an aperture in the apertured electrostatic shield to permit passage of the pulsed jet droplet flow through the bowl.

Claim 41

The isolator of claim 39 further comprising a vertical pipe extending above the bowl about the aperture, positioned to receive the pulsed jet droplet flow from the nozzle chamber.

Claim 42

The isolator of claim 40 in which the aperture in the bowl is no larger than said in line aperture in the electrostatic shield.

Claim 43

The isolator of claim 41 in which the pipe on the bowl surrounding the pulsed jet droplet flow path further includes, in its interior, an inverted frusto-conical element in the form of a funnel having an opening in a lower portion thereof for the pulsed jet droplet flow path which is smaller than said apertures in the bowl and in the electrostatic shield.

Claim 44

The isolator of claim 1 in which the nozzle chamber, mounted above the receptacle, has an aperture in a bottom portion thereof which is a nozzle aperture, and the means for coupling electrostatic coating material to the nozzle chamber comprises a manifold surrounding the nozzle chamber and communicating therewith through a plurality of radial bores between the manifold and the chamber.

Claim 45

An electrostatic coating system including a source of electrically conductive coating material at a ground potential, an electrostatic coating dispensing device for dispensing electrically conductive coating material onto objects to be coated, means for electrostatically charging the coating material dispensed by the dispensing device to a high electrostatic potential, and an isolator for coupling electrically conductive coating material from the coating material source to the coating material dispensing device while maintaining electrical isolation therebetween, the isolator comprising: a housing; a charged coating material receptacle having an opening in an upper portion thereof and mounted in the housing; means for coupling coating material from the charged coating material receptacle through the housing to the coating material dispensing device, whereby electrically conductive coating material in the receptacle is electrostatically charged by the charging means through the conductive coating material in the coupling means; a grounded coating material nozzle chamber mounted above the charged coating material receptacle and having an aperture in a bottom portion thereof defining a coating material nozzle; means for coupling coating material from the source of coating material to the grounded coating material nozzle chamber; means for mechanically vibrating the coating material in the grounded coating material nozzle chamber to produce a pulsed jet droplet flow of coating material in a relatively confined path from the aperture in the bottom portion of the grounded nozzle chamber downwardly into the opening in the upper portion of the charged coating material receptacle; and a grounded electrostatic shield mounted between the receptacle and the nozzle chamber to substantially shield the grounded coating material nozzle chamber from electrical potentials below the shield including the electrical potential of the charged coating material in the charge coating material receptacle, the electrostatic shield having an aperture sized to permit pulsed jet droplet flow of coating material in a relatively confined path from the grounded coating material nozzle chamber into the charged coating material receptacle.

Claim 46

An electrostatic coating system including a source of electrically conductive coating material at a ground potential, an electrostatic coating dispensing device for dispensing electrically conductive coating material onto objects to be coated, means for electrostatically charging the coating material dispensed by the dispensing device to a high electrostatic potential, and an isolator for coupling electrically conductive coating material from the coating material source to the coating material dispensing device while maintaining electrical isolation therebetween, the isolator comprising: a housing; a charged coating material receptacle having an opening in an upper portion thereof and mounted in the housing; means for coupling coating material from the charged coating material receptacle through the housing to the coating material dispensing device, whereby electrically conductive coating material in the receptacle is electrostatically charged by the charging means through the conductive coating material in the coupling means; a grounded coating material nozzle chamber mounted above the charged coating material receptacle and having an aperture in a bottom portion thereof defining a coating material nozzle; means for coupling coating material from the source of coating material to the grounded coating material nozzle chamber; means for mechanically vibrating the coating material in the grounded coating material nozzle chamber to produce a pulsed jet droplet flow of coating material in a relatively confined path from the aperture in the bottom portion of the grounded nozzle chamber downwardly into the opening in the upper portion of the charged coating material receptacle; and a grounded electrostatic shield mounted between the receptacle and the nozzle chamber to substantially shield the grounded coating material nozzle chamber from electrical potentials below the shield including the electrical potential of the charged coating material in the charge coating material receptacle, the electrostatic shield having an aperture sized to permit pulsed jet droplet flow of coating material in a relatively confined path from the grounded coating material nozzle chamber into the charged coating material receptacle.

Claim 47

The coating system of claim 44 in which the grounded coating material nozzle chamber is mounted within the housing above the charged coating material receptacle.

Claim 48

The coating system of claim 44 in which the grounded coating material nozzle chamber, mounted above the charged coating material receptacle, has an aperture in a bottom portion thereof which is a nozzle aperture.

Claim 49

The coating system of claim 46 in which the means for coupling electrostatic coating material from the source of coating material to the grounded coating material nozzle chamber comprises a bore in a wall of the nozzle chamber.

Claim 50

The coating system of claim 44 in which the means for mechanically vibrating the electrostatic coating material comprises means for producing oscillatory pressure changes at the aperture in the bottom portion of the grounded coating material nozzle chamber.

Claim 51

The coating system of claim 48 in which the means for mechanically vibrating the electrostatic coating material further comprises a diaphragm forming one wall of the grounded coating material nozzle chamber.

Claim 52

The coating system of claim 44 in which the means for mechanically vibrating the coating material in the grounded coating material nozzle chamber comprises a diaphragm forming a top wall of the grounded coating material nozzle chamber and a vibrator coupled to the diaphragm mounted above the grounded coating material nozzle chamber for driving the diaphragm to produce oscillatory pressure changes in the grounded coating material nozzle chamber.

Claim 53

The coating system of claim 44 which further comprises means for sensing droplet separation in the pulsed jet droplet flow at a location between the charged coating material receptacle and the grounded coating material nozzle chamber and means responsive to the sensed separation for controlling the means for mechanically vibrating the coating material in the grounded coating material nozzle chamber.

Claim 54

The coating system of claim 44 which further comprises a coating material collection bowl mounted above the electrostatic shield and below the grounded coating material nozzle chamber, for collecting splattered coating material from the aperture in the bottom portion of the grounded coating material nozzle chamber, the bowl having an aperture in line with an aperture in the apertured electrostatic shield to permit passage of the pulsed jet droplet flow through the bowl.

Claim 55

The coating system of claim 52 further comprising a vertical pipe extending above the bowl about the bowl aperture, positioned to receive the pulsed jet droplet flow from the grounded coating material nozzle chamber.

Claim 56

The coating system of claim 44 in which the grounded coating material nozzle chamber, mounted above the charged coating material receptacle, has an aperture in a bottom portion thereof which is a nozzle aperture, and the means for coupling coating material from the source of coating material to the grounded coating material nozzle chamber comprises a manifold surrounding the nozzle chamber and communicating therewith through a plurality of radial bores between the manifold and the chamber.

Claim 57

An isolator for an electrostatic coating system comprising: a housing; a receptacle, having an opening in an upper portion thereof and mounted in the housing, for electrostatic coating material which is at a first electrical potential; an outlet conduit communicating between the receptacle and the exterior of the housing for supplying electrostatic coating material from the receptacle for use by an electrostatic coating device; droplet supply means for supplying droplets of coating material at a second electrostatic potential at a location spaced above said receptacle for downward flow into said opening in the upper portion of said receptacle, and

Claim 58

An isolator for an electrostatic coating system comprising: a housing; a receptacle, having an opening in an upper portion thereof and mounted in the housing, for electrostatic coating material which is at a first electrical potential; an outlet conduit communicating between the receptacle and the exterior of the housing for supplying electrostatic coating material from the receptacle for use by an electrostatic coating device; droplet supply means for supplying droplets of coating material at a second electrostatic potential at a location spaced above said receptacle for downward flow into said opening in the upper portion of said receptacle, and

Claim 59

an electrostatic shield at an electrical potential substantially closer to said second potential than to said first potential, mounted between said droplet supply means and said receptacle opening to substantially electrostatically shield said droplet supply means from electrostatic potentials below said shield including the electrostatic potential of the coating material in said receptacle.

Claim 60

an electrostatic shield at an electrical potential substantially closer to said second potential than to said first potential, mounted between said droplet supply means and said receptacle opening to substantially electrostatically shield said droplet supply means from electrostatic potentials below said shield including the electrostatic potential of the coating material in said receptacle.

Claim 61

The isolator of claim 55 wherein said droplet supply means includes: a nozzle chamber, for electrostatic coating material at a second electrical potential, mounted above the receptable and having an aperture in a bottom portion thereof, to serve as a nozzle for dispensing electrostatic coating material, means for coupling electrostatic coating material to the nozzle chamber from an electrostatic coating material supply, and means for mechanically vibrating the electrostatic coating material in the nozzle chamber to produce a pulsed jet droplet flow of electrostatic coating material from the aperture in the bottom portion of the nozzle chamber into the opening in the upper portion of the receptacle, said means for mechanically vibrating the electrostatic coating material including means for producing oscillatory pressure changes at the aperture in the bottom portion of the nozzle chamber.

Claim 62

The isolator of claim 56 in which the means for mechanically vibrating the electrostatic coating material further comprises a diaphragm forming one wall of the nozzle chamber.

Claim 63

The isolator of claim 57 in which the means for mechanically vibrating the electrostatic coating material further comprises a piston attached to the diaphragm and movable within the nozzle chamber.

Claim 64

The isolator of claim 58 in which the nozzle chamber, mounted above the receptacle, has an aperture in a bottom portion thereof which is a nozzle aperture.

Claim 65

The isolator of claim 59 in which the means for coupling electrostatic coating material from the coating material supply to the nozzle chamber comprises a bore in a wall of the nozzle chamber.

Claim 66

The isolator of claim 60 in which the piston is reciprocable in the nozzle chamber and operable to cover and uncover the bore in the nozzle chamber.

Claim 67

The isolator of claim 56 in which the means for mechanically vibrating the electrostatic coating material in the nozzle chamber comprises a diaphragm forming a top wall of the nozzle chamber and a vibrator coupled to the diaphragm mounted above the nozzle chamber for driving the diaphragm to produce oscillatory pressure changes in the nozzle chamber.

Claim 68

The isolator of claim 62 which further comprises means for varying the frequency of vibration of the vibrator.

Claim 69

The isolator of claim 62 which further comprises means for varying the force applied to the membrane by the vibrator.

Claim 70

THe isolator of claim 55 which further comprises means for sensing droplet separation in the pulsed jet droplet flow at a location between the receptacle and the droplet supply means, and means responsive to the sensed separation for controlling the droplet supply means to regulate the droplet separation.

Claim 71

The isolator of claim 65 wherein said droplet supply means includes: a nozzle chamber, for electrostatic coating material at a second electrical potential, mounted above the receptacle and having an aperture in a bottom portion thereof, to serve as a nozzle for dispensing electrostatic coating material, means for coupling electrostatic coating material to the nozzle chamber from an electrostatic coating material supply, means for mechanically vibrating the electrostatic coating material in the nozzle chamber to produce a pulsed jet droplet flow of electrostatic coating material from the aperture in the bottom portion of the nozzle chamber into the opening in the upper portion of the receptacle, and said means for mechanically vibrating the electrostatic coating material in the nozzle chamber comprises a diaphragm forming a top wall of the nozzle chamber and a vibrator coupled to the diaphragm mounted above the nozzle chamber for driving the diaphragm to produce oscillatory pressure changes in the nozzle chamber.

Claim 72

The isolator of claim 66 which further comprises means for varying the force applied to the diaphragm by the vibrator.

Claim 73

The isolator of claim 67 which further comprises means for varying the frequency of vibration of the diaphragm by the vibrator.

Claim 74

The isolator of claim 68 in which the means for controlling the means for mechanically vibrating the electrostatic coating material in the nozzle chamber comprises means for controlling the frequency and force of vibration of the vibrator.

Claim 75

An isolator for an electrostatic coating system comprising: a housing; a receptacle, having an opening in an upper portion thereof and mounted in the housing, for electrostatic coating material which is at a first electrical potential; an outlet conduit communicating between the receptacle and the exterior of the housing for supplying electrostatic coating material from the receptacle for use by an electrostatic coating device; a nozzle chamber, for electrostatic coating material at a second electrical potential, mounted above the receptacle and having an aperture in a bottom portion thereof, to serve as a nozzle for dispensing electrostatic coating material; means for coupling electrostatic coating material to the nozzle chamber from an electrostatic coating material supply; means for forming coating material dispensed from the aperture in the bottom portion of the nozzle chamber into discrete droplets falling downwardly in a relatively confined path; and an electrostatic shield, at an electrical potential substantially closer to said second electrical potential than to said first electrical potential, mounted between the receptacle and the nozzle chamber to substantially electrically shield an area below the nozzle chamber in which said discrete droplets are formed from electrical potentials below the shield including the electrical potential of the electrostatic coating material in the receptacle, the electrostatic shield having an aperture sized to permit the passage of electrostatic coating material in a relatively confined path from the nozzle chamber to the receptacle.

Claim 76

An isolator for an electrostatic coating system comprising: a housing; a receptacle, having an opening in an upper portion thereof and mounted in the housing, for electrostatic coating material which is at a first electrical potential; an outlet conduit communicating between the receptacle and the exterior of the housing for supplying electrostatic coating material from the receptacle for use by an electrostatic coating device; a nozzle chamber, for electrostatic coating material at a second electrical potential, mounted above the receptacle and having an aperture in a bottom portion thereof, to serve as a nozzle for dispensing electrostatic coating material; means for coupling electrostatic coating material to the nozzle chamber from an electrostatic coating material supply; means for forming coating material dispensed from the aperture in the bottom portion of the nozzle chamber into discrete droplets falling downwardly in a relatively confined path; and an electrostatic shield, at an electrical potential substantially closer to said second electrical potential than to said first electrical potential, mounted between the receptacle and the nozzle chamber to substantially electrically shield an area below the nozzle chamber in which said discrete droplets are formed from electrical potentials below the shield including the electrical potential of the electrostatic coating material in the receptacle, the electrostatic shield having an aperture sized to permit the passage of electrostatic coating material in a relatively confined path from the nozzle chamber to the receptacle.

Claim 77

The isolator of claim 70 in which the nozzle chamber is mounted within the housing above the receptacle.

Claim 78

The isolator of claim 71 in which the electrostatic shield is mounted in the housing between the receptacle and the nozzle chamber.

Claim 79

The isolator of claim 72 in which the second electrical potential of the electrostatic coating material in the nozzle chamber is a ground potential.

Claim 80

The isolator of claim 73 in which the electrostatic shield is at a ground potential.

Claim 81

The isolator of claim 70 which further comprises a coating material collection bowl mounted above the electrostatic shield and below the nozzle chamber, for collecting splattered coating material from the aperture in the bottom portion of the nozzle chamber, the bowl having an aperture in line with an aperture in the apertured electrostatic shield to permit passage of the droplets through the bowl.

Claim 82

The isolator of claim 75 further comprising a vertical pipe extending above the bowl about the bowl aperture, positioned to receive the droplet flow from the nozzle chamber.

Claim 83

An isolator for transferring liquid from a first quantity of liquid at a first electrostatic potential to a second quantity of liquid at a second electrostatic potential, different from said first potential, comprising: a receptacle for said second quantity of liquid, having an opening in an upper portion thereof; an outlet conduit coupled from the receptacle for the second quantity of liquid to a use location for said liquid; droplet supply means for supplying in a relatively confined downward flow path, droplets of coating material at a first electrostatic potential at a location spaced above said receptacle for flow into said opening in the upper portion of said receptacle, and an electrostatic shield at an electrical potential substantially closer to said first potential than to said second potential, mounted between said droplet supply means and said receptacle opening to substantially electrostatically shield said droplet supply means from electrostatic potential below said shield including the electrostatic potential of the coating material in said receptacle, said electrostatic shield having an aperture sized to permit the passage of said droplets in said relatively confined flow path from said droplet supply means to said receptacle.

Claim 84

An isolator for transferring liquid from a first quantity of liquid at a first electrostatic potential to a second quantity of liquid at a second electrostatic potential, different from said first potential, comprising: a receptacle for said second quantity of liquid, having an opening in an upper portion thereof; an outlet conduit coupled from the receptacle for the second quantity of liquid to a use location for said liquid; droplet supply means for supplying in a relatively confined downward flow path, droplets of coating material at a first electrostatic potential at a location spaced above said receptacle for flow into said opening in the upper portion of said receptacle, and an electrostatic shield at an electrical potential substantially closer to said first potential than to said second potential, mounted between said droplet supply means and said receptacle opening to substantially electrostatically shield said droplet supply means from electrostatic potential below said shield including the electrostatic potential of the coating material in said receptacle, said electrostatic shield having an aperture sized to permit the passage of said droplets in said relatively confined flow path from said droplet supply means to said receptacle.

Claim 85

An isolator for transferring liquid from a first quantity of liquid at a first electrostatic potential to a second quantity of liquid at a second electrostatic potential, different from said first potential, comprising: a receptacle for said second quantity of liquid, having an opening in an upper portion thereof; an outlet conduit coupled from the receptacle for the second quantity of liquid to a use location for said liquid; a nozzle chamber for the first quantity of liquid, mounted above the receptacle for the second quantity of liquid and having an aperture in a bottom portion thereof, to serve as a nozzle for dispensing liquid; means for coupling liquid to the nozzle chamber for the first quantity of liquid from a liquid supply; means for forming the liquid dispensed from the nozzle chamber for the first quantity of liquid into discrete droplets falling downwardly in a relatively confined path; and an electrostatic shield, at an electrical potential substantially closer to the electrical potential of the first quantity of liquid than to the electrical potential of the second quantity of liquid, mounted between the receptacle and the nozzle chamber at a location to substantially electrically shield areas of droplet formation beneath the nozzle chamber for the first quantity of liquid from electrical potentials below the shield, including the electrical potential of the second quantity of liquid, the electrostatic shield having an aperture sized to permit the passage of liquid droplets from the first quantity of liquid in a relatively confined path to the second quantity of liquid.

Claim 86

An isolator for transferring liquid from a first quantity of liquid at a first electrostatic potential to a second quantity of liquid at a second electrostatic potential, different from said first potential, comprising: a receptacle for said second quantity of liquid, having an opening in an upper portion thereof; an outlet conduit coupled from the receptacle for the second quantity of liquid to a use location for said liquid; a nozzle chamber for the first quantity of liquid, mounted above the receptacle for the second quantity of liquid and having an aperture in a bottom portion thereof, to serve as a nozzle for dispensing liquid; means for coupling liquid to the nozzle chamber for the first quantity of liquid from a liquid supply; means for forming the liquid dispensed from the nozzle chamber for the first quantity of liquid into discrete droplets falling downwardly in a relatively confined path; and an electrostatic shield, at an electrical potential substantially closer to the electrical potential of the first quantity of liquid than to the electrical potential of the second quantity of liquid, mounted between the receptacle and the nozzle chamber at a location to substantially electrically shield areas of droplet formation beneath the nozzle chamber for the first quantity of liquid from electrical potentials below the shield, including the electrical potential of the second quantity of liquid, the electrostatic shield having an aperture sized to permit the passage of liquid droplets from the first quantity of liquid in a relatively confined path to the second quantity of liquid.

Claim 87

An isolator for transferring liquid from a first quantity of liquid at a first electrostatic potential to a second quantity of liquid at a second electrostatic potential, different from said first potential, comprising: a receptacle for said second quantity of liquid, having an opening in an upper portion thereof; a nozzle chamber for the first quantity of liquid, mounted above the receptacle for the second quantity of liquid and having an aperture in a bottom portion thereof, to serve as a nozzle for dispening liquid; means for mechanically vibrating the first quantity of liquid to produce a pulsed jet droplet flow of liquid in a relatively confined path, from the aperture in the bottom portion of the nozzle chamber for the first quality of liquid, downwardly into the opening in the upper portion of the receptacle for the second quantity of liquid; and an electrostatic shield, at an electrical potential substantially closer to the electrical potential of the first quantity of liquid than to the electrical potential of the second quantity of liquid, mounted between the receptacle and the nozzle chamber at a location to substantially electrically shield locations of droplet formation beneath the nozzle chamber for the first quantity of liquid from electrical potentials below the shield including the electrical potential of the second quantity of liquid, the electrostatic shield having an aperture sized to permit the passage of liquid droplets from the first quantity of liquid in a relatively confined path to the second quantity of liquid.

Claim 88

An isolator for transferring liquid from a first quantity of liquid at a first electrostatic potential to a second quantity of liquid at a second electrostatic potential, different from said first potential, comprising: a receptacle for said second quantity of liquid, having an opening in an upper portion thereof; a nozzle chamber for the first quantity of liquid, mounted above the receptacle for the second quantity of liquid and having an aperture in a bottom portion thereof, to serve as a nozzle for dispening liquid; means for mechanically vibrating the first quantity of liquid to produce a pulsed jet droplet flow of liquid in a relatively confined path, from the aperture in the bottom portion of the nozzle chamber for the first quality of liquid, downwardly into the opening in the upper portion of the receptacle for the second quantity of liquid; and an electrostatic shield, at an electrical potential substantially closer to the electrical potential of the first quantity of liquid than to the electrical potential of the second quantity of liquid, mounted between the receptacle and the nozzle chamber at a location to substantially electrically shield locations of droplet formation beneath the nozzle chamber for the first quantity of liquid from electrical potentials below the shield including the electrical potential of the second quantity of liquid, the electrostatic shield having an aperture sized to permit the passage of liquid droplets from the first quantity of liquid in a relatively confined path to the second quantity of liquid.