US3774844A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic deposition coating system
Assignee: Walberg & Co A
•
Filing: 1972-03-23
•
Granted: 1973-11-27
•
Expires: 1992-03-23
Abstract
Abstract Electrostatic deposition spray coating systems in which water base paints, teflon coatings and other highly conductive materials are sprayed utilize the conductive fluid in a paint conduit of insulating material for connecting an ionizing electrode to the high voltage power supply of the system. Higher operator safety is accomplished by mixing the conductive coating material fluid and air internally prior to rejecting it through an air cap and by limiting the exposed portion of the ionizing electrode to a short needle point or knife edge.
Inventors
- 👤 A Walberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:33
CPC Classifications
B; B05; B05B; B05B5/00; B05B5/16; B05B5/1608; B05B5/025; B05B5/03
Claims Analysis
Total Claims: 68
Claim 1
Independent Claim
207 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with an internal chamber and a passage therein having an intake for connection to a source of coating material and an outlet through which coating material is ejected into said internal chamber, means comprising air inlets to said chamber for atomizing said coating material in said chamber prior to ejection, means comprising an aperture in said chamber for ejecting the atomized coating material into the atmosphere, a container for holding conductive coating, a fluid conduit having at least an inner layer of electrical non-conducting material connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, a high voltage supply connected between conductive coating material in said container and work to be coated, and means applying an electrostatic field to the atomized coating material ejected through said aperture of said chamber including an electrical conducting element extending forwardly of said body and connected to said conducting coating material prior to atomization in said chamber, the coating material in said fluid conduit being the sole electrical conductor of high voltage between the coating material in the container and the electrical conducting element extending forwardly.
Claim 2
Dependent Claim
207 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with an internal chamber and a passage therein having an intake for connection to a source of coating material and an outlet through which coating material is ejected into said internal chamber, means comprising air inlets to said chamber for atomizing said coating material in said chamber prior to ejection, means comprising an aperture in said chamber for ejecting the atomized coating material into the atmosphere, a container for holding conductive coating, a fluid conduit having at least an inner layer of electrical non-conducting material connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, a high voltage supply connected between conductive coating material in said container and work to be coated, and means applying an electrostatic field to the atomized coating material ejected through said aperture of said chamber including an electrical conducting element extending forwardly of said body and connected to said conducting coating material prior to atomization in said chamber, the coating material in said fluid conduit being the sole electrical conductor of high voltage between the coating material in the container and the electrical conducting element extending forwardly.
Claim 3
Dependent Claim
51 words
The electrostatic deposition coating system according to claim 1 wherein said spray gun body comprises a rear end having a shield of electrical conductive material exposed to the atmosphere and a center section having all parts therein composed of electrical non-conductive material and connecting said forward end and said rear end.
Claim 4
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 1 wherein said fluid conduit for transporting coating material is composed of electrical non-conducting material and the coating material in said container is electrically insulated from ground.
Claim 5
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 2 wherein said fluid conduit for transporting coating material is composed of electrical non-conducting material and the coating material in said container is electrically insulated from ground.
Claim 6
Dependent Claim
44 words
The electrical deposition coating system according to claim 4 wherein said fluid conduit of electrical non-conducting material is covered by a shield of electrical conducting material, said conduit shield being connected to said shield on said spray gun body rear portion and to ground.
Claim 7
Dependent Claim
27 words
The electrostatic deposition coating system according to claim 3 wherein a multiplicity of said spray gun bodies are connected through respective said conduits to a single container.
Claim 8
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 6, wherein each said non-conducting conduit is connected to a fluid regulator, said fluid regulators being connected by conduit means electrically insulated from ground to said container.
Claim 9
Dependent Claim
44 words
The electrostatic deposition coating system according to claim 7, wherein said conduit means comprises a delivery conduit, a return conduit, a pumping means forcing coating material from said container through said delivery conduit to said regulators and through sAid return conduit to said container.
Claim 10
Dependent Claim
181 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with an internal chamber and a passage therein having an intake for connection to a source of coating material and an outlet through which coating material is ejected into said internal chamber, means comprising air inlets to said chamber for atomizing said coating material in said chamber prior to ejection, means comprising an aperture in said chamber for ejecting the atomized coating material into the atmosphere, a shield of electrical non-conducting material surrounding all conducting portions on the forward end of said body, a fluid conduit connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, a high voltage supply connected between conductive coating material in said container and work to be coated, and means applying an electrostatic field to the atomized coating material ejected through said aperture of said chamber including an electrical conducting element extending through said shield at said aperture and connected to said conducting coating material prior to atomization in said chamber.
Claim 11
Dependent Claim
181 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with an internal chamber and a passage therein having an intake for connection to a source of coating material and an outlet through which coating material is ejected into said internal chamber, means comprising air inlets to said chamber for atomizing said coating material in said chamber prior to ejection, means comprising an aperture in said chamber for ejecting the atomized coating material into the atmosphere, a shield of electrical non-conducting material surrounding all conducting portions on the forward end of said body, a fluid conduit connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, a high voltage supply connected between conductive coating material in said container and work to be coated, and means applying an electrostatic field to the atomized coating material ejected through said aperture of said chamber including an electrical conducting element extending through said shield at said aperture and connected to said conducting coating material prior to atomization in said chamber.
Claim 12
Dependent Claim
51 words
The electrostatic deposition coating system according to claim 9 wherein said spray gun body comprises a rear end having a shield of electrical conductive material exposed to the atmosphere and a center section having all parts therein composed of electrical non-conductive material and connecting said forward end and said rear end.
Claim 13
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 9 wherein said fluid conduit for transporting coating material is composed of electrical non-conducting material and the coating material in said container is electrically insulated from ground.
Claim 14
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 10 wherein said fluid conduit for transporting coating material is composed of electrical non-conducting material and the coating material in said container is electrically insulated from ground.
Claim 15
Dependent Claim
44 words
The electrical deposition coating system according to claim 12 wherein said fluid conduit of electrical non-conducting material is covered by a shield of electrical conducting material, said conduit shield being connected to said shield on said spray gun body rear portion and to ground.
Claim 16
Dependent Claim
27 words
The electrostatic deposition coating system according to claim 11, wherein a multiplicity of said spray gun bodies are connected through respective said conduits to a single container.
Claim 17
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 14, wherein each said non-conducting conduit is connected to a fluid regulator, said fluid regulators being connected by conduit means electrically insulated from ground to said container.
Claim 18
Dependent Claim
45 words
The electrostatic deposition coating system according to claim 15, wherein said conduit means comprises a delivery conduit, a return conduit, and a pumping means forcing coating material from said container through said delivery conduit to said regulators and through said return conduit to said container.
Claim 19
Dependent Claim
31 words
The electrostatic deposition coating system according to claim 9, wherein said electrical conducting element comprises a needle point having only its sharp tip protruding from said shield of electrical non-conducting material.
Claim 20
Dependent Claim
31 words
The electrostatic deposition coating system according to claim 9, wherein said electrical conducting element comprises a knife edge having only its sharp tip protruding from said shield of electrical non-conducting material.
Claim 21
Dependent Claim
50 words
The electrostatic deposition coating system according to claim 9, wherein said electrical conducting element comprises side surfaces of said aperture through which coating material is ejected into the atmosphere terminating in a forwardly facing knife edge having only its sharp tip protruding forwardly of said shield of electrical non-conducting material.
Claim 22
Dependent Claim
185 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with a passage therein having an intake for connection to a source of coating material and an aperture through which coating material is ejected into the atmosphere from the forward end of the body, means for atomizing said coating material on or prior to ejection, a container for holding conductive coating, a fluid conduit having at least an inner layer of electrical non-conducting material connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, a high voltage supply connected between conductive coating material in said container and work to be coated, and means applying an electrostatic field to the atomized coating material ejected through said aperture of said spray gun body including an electrical conducting element extending forwardly of said body and connected to said conducting coating material prior to atomization, the coating material in said fluid conduit being the sole electrical conductor of high voltage between the coating material in the container and the electrical conducting element extending forwardly.
Claim 23
Dependent Claim
185 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with a passage therein having an intake for connection to a source of coating material and an aperture through which coating material is ejected into the atmosphere from the forward end of the body, means for atomizing said coating material on or prior to ejection, a container for holding conductive coating, a fluid conduit having at least an inner layer of electrical non-conducting material connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, a high voltage supply connected between conductive coating material in said container and work to be coated, and means applying an electrostatic field to the atomized coating material ejected through said aperture of said spray gun body including an electrical conducting element extending forwardly of said body and connected to said conducting coating material prior to atomization, the coating material in said fluid conduit being the sole electrical conductor of high voltage between the coating material in the container and the electrical conducting element extending forwardly.
Claim 24
Dependent Claim
51 words
The electrostatic deposition coating system according to claim 20 wherein said spray gun body comprises a rear end having a shield of electrical conductive material exposed to the atmosphere and a center section having all parts therein composed of electrical non-conductive material and connecting said forward end and said rear end.
Claim 25
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 20 wherein said fluid conduit for transporting coating material is composed of electrical non-conducting material and the coating material in said container is electrically insulated from ground.
Claim 26
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 21 wherein said fluid conduit for transporting coating material is composed of electrical non-conducting material and the coating material in said container is electrically insulated from ground.
Claim 27
Dependent Claim
44 words
The electrostatic deposition coating system according to claim 23 wherein said fluid conduit of electrical non-conducting material is covered by a shield of electrical conducting material, said conduit shield being connected to said shield on said spray gun body rear portion and to ground.
Claim 28
Dependent Claim
27 words
The electrostatic deposition coating system according to claim 22, wherein a multiplicity of said spray gun bodies are connected through respective said conduits to a single container.
Claim 29
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 25, wherein each said non-conducting conduit is connected to a fluid regulator, said fluid regulators being connected by conduit means electrically insulated from ground to said container.
Claim 30
Dependent Claim
45 words
The electrostatic deposition coating system according to claim 26, wherein said conduit means comprises a delivery conduit, a return conduit, and a pumping means forcing coating material from said container through said delivery conduit to said regulators and through said return conduit to said container.
Claim 31
Dependent Claim
16 words
The coating system according to claim 20, wherein said container is constructed of electrically nonconductive material.
Claim 32
Dependent Claim
159 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with an internal chamber and a passage therein having an intake for connection to a source of coating material and an outlet through which coating material is ejected into said internal chamber, means comprising air inlet to said chamber for atomizing said coating material in said chamber prior to ejection, means comprising an aperture in said chamber for ejecting the atomized coating material into the atmosphere, a shield of electrical non-conducting material surrounding all conducting portions on the forward end of said body, means applying an electrostatic field to the atomized coating material ejeCted through said aperture of said chamber including an electrical conducting element extending through said shield at said aperture and connected to said conducting coating material prior to atomization in said chamber, and means for charging said electrical conducting element to a high potential with respect to work to be coated.
Claim 33
Dependent Claim
159 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with an internal chamber and a passage therein having an intake for connection to a source of coating material and an outlet through which coating material is ejected into said internal chamber, means comprising air inlet to said chamber for atomizing said coating material in said chamber prior to ejection, means comprising an aperture in said chamber for ejecting the atomized coating material into the atmosphere, a shield of electrical non-conducting material surrounding all conducting portions on the forward end of said body, means applying an electrostatic field to the atomized coating material ejeCted through said aperture of said chamber including an electrical conducting element extending through said shield at said aperture and connected to said conducting coating material prior to atomization in said chamber, and means for charging said electrical conducting element to a high potential with respect to work to be coated.
Claim 34
Dependent Claim
31 words
The electrostatic deposition coating system according to claim 29, wherein said electrical conducting element comprises a needle point having only its sharp tip protruding from said shield of electrical non-conducting material.
Claim 35
Dependent Claim
31 words
The electrostatic deposition coating system according to claim 29, wherein said electrical conducting element comprises a knife edge having only its sharp tip protruding from said shield of electrical non-conducting material.
Claim 36
Dependent Claim
50 words
The electrostatic deposition coating system according to claim 29, wherein said electrical conducting element comprises side surfaces of said aperture through which coating material is ejected into the atmosphere terminating in a forwardly facing knife edge having only its sharp tip protruding forwardly of said shield of electrical non-conducting material.
Claim 37
Dependent Claim
168 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with a passage therein having an intake for connection to a source of coating material and an aperture through which coating material is ejected into the atmosphere from the forward end of the body, means for atomizing said coating material on or prior to ejection, a container for holding conductive coating, a shield of electrical non-conducting material surrounding all conducting portions on the forward end of said body, a fluid conduit connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, a high voltage supply connected between conductive coating material in said container and work to be coated, and means applying an electrostatic field to the atomized coating material ejected through said aperture of said spray gun body including an electrical conducting element extending through said shield at said aperture and connected to said conducting coating material prior to atomization in said chamber.
Claim 38
Dependent Claim
168 words
An electrostatic deposition coating system comprising: a spray gun body having a forward end provided with a passage therein having an intake for connection to a source of coating material and an aperture through which coating material is ejected into the atmosphere from the forward end of the body, means for atomizing said coating material on or prior to ejection, a container for holding conductive coating, a shield of electrical non-conducting material surrounding all conducting portions on the forward end of said body, a fluid conduit connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, a high voltage supply connected between conductive coating material in said container and work to be coated, and means applying an electrostatic field to the atomized coating material ejected through said aperture of said spray gun body including an electrical conducting element extending through said shield at said aperture and connected to said conducting coating material prior to atomization in said chamber.
Claim 39
Dependent Claim
51 words
The electrostatic deposition coating system according to claim 33 wherein said spray gun body comprises a rear end having a shield of electrical conductive material exposed to the atmosphere and a center section having all parts therein composed of electrical non-conductive material and connecting said forward end and said rear end.
Claim 40
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 33 wherein said fluid conduit for transporting coating material is composed of electrical non-conducting material and the coating material in said container is electrically insulated from ground.
Claim 41
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 34 wherein said fluid conduit for transporting coating material is composed of electrical non-conducting material and the coating material in said container is electrically insulated from ground.
Claim 42
Dependent Claim
44 words
The electrostatic deposition coating system according to claim 36 wherein said fluid conduit of electrical non-conducting material is covered by a shield of electrical conducting material, said conduit shield being connected to said shield on said spray gun body rear portion and to ground.
Claim 43
Dependent Claim
27 words
The electrostatic deposition coating system according to claim 35, wherein a multiplicity of said spray gun bodies are connected through respective said conduits to a single container.
Claim 44
Dependent Claim
35 words
The electrostatic deposition coating system according to claim 38, wherein each said non-conducting conduit is connected to a fluid regulator, said fluid regulators being connected by conduit means electrically insulated from ground to said container.
Claim 45
Dependent Claim
45 words
The electrostatic deposition coating system according to claim 39, wherein said conduit means comprises a deliVery conduit, a return conduit, and a pumping means forcing coating material from said container through said delivery conduit to said regulators and through said return conduit to said container.
Claim 46
Dependent Claim
31 words
The electrostatic deposition coating system according to claim 33, wherein said electrical conducting element comprises a needle point having only its sharp tip protruding from said shield of electrical non-conducting material.
Claim 47
Dependent Claim
31 words
The electrostatic deposition coating system according to claim 33, wherein said electrical conducting element comprises a knife edge having only its sharp tip protruding from said shield of electrical non-conducting material.
Claim 48
Dependent Claim
50 words
The electrostatic deposition coating system according to claim 33, wherein said electrical conducting element comprises side surfaces of said aperture through which coating material is ejected into the atmosphere terminating in a forwardly facing knife edge having only its sharp tip protruding forwardly of said shield of electrical non-conducting material.
Claim 49
Dependent Claim
155 words
A coating system comprising: a spray gun for atomizing and ejecting coating material into the atmosphere having a forward end provided with a passage therein having an intake, a container for holding conductive coating material, a high voltage supply having a maximum voltage output connected between conductive coating material in said container and work to be coated, a fluid conduit connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, said transported conductive coating material having a high effective capacitance and said conduit having a layer of electrically nonconductive material adjacent said transported conductive coating material to electrically insulate said conductive coating material from electrical potential differences equal to said power supply maximum voltage output at said high effective capacitance, and means applying an electrostatic field to the atomized coating material ejected from said spray gun connected to said coating material at said spray gun.
Claim 50
Dependent Claim
155 words
A coating system comprising: a spray gun for atomizing and ejecting coating material into the atmosphere having a forward end provided with a passage therein having an intake, a container for holding conductive coating material, a high voltage supply having a maximum voltage output connected between conductive coating material in said container and work to be coated, a fluid conduit connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, said transported conductive coating material having a high effective capacitance and said conduit having a layer of electrically nonconductive material adjacent said transported conductive coating material to electrically insulate said conductive coating material from electrical potential differences equal to said power supply maximum voltage output at said high effective capacitance, and means applying an electrostatic field to the atomized coating material ejected from said spray gun connected to said coating material at said spray gun.
Claim 51
Dependent Claim
23 words
The coating system according to claim 44, wherein said layer of electrically nonconductive material is surrounded by a shield of electrically conductive material.
Claim 52
Dependent Claim
16 words
The coating system according to claim 44, wherein said container is constructed of electrically nonconductive material.
Claim 53
Dependent Claim
159 words
A coating system comprising: a spray gun for atomizing and ejecting coating material into the atmosphere having a forward end provided with a passage therein having an intake, a container for holding conductive coating material, a high voltage supply connected to apply at least 50,000 volts direct current between conductive coating material in said container and work to be coated, a fluid conduit connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, said transported conductive coating material having a high effective capacitance and said conduit having a layer of electrically nonconductive material adjacent said transported coating material to electrically insulate said conductive coating material from said work and other objects at an electrical potential difference of 50,000 volts at said high effective capacitance, and means applying an electrostatic field to the atomized coating material ejected from said spray gun connected to said coating material at said spray gun.
Claim 54
Dependent Claim
159 words
A coating system comprising: a spray gun for atomizing and ejecting coating material into the atmosphere having a forward end provided with a passage therein having an intake, a container for holding conductive coating material, a high voltage supply connected to apply at least 50,000 volts direct current between conductive coating material in said container and work to be coated, a fluid conduit connecting said container and said intake to transport conductive coating material from said container to said spray gun body passage, said transported conductive coating material having a high effective capacitance and said conduit having a layer of electrically nonconductive material adjacent said transported coating material to electrically insulate said conductive coating material from said work and other objects at an electrical potential difference of 50,000 volts at said high effective capacitance, and means applying an electrostatic field to the atomized coating material ejected from said spray gun connected to said coating material at said spray gun.
Claim 55
Dependent Claim
28 words
The coating system according to claim 47, wherein said layer of electrically nonconductive material is surrounded by a shield of electrically conductive material connected to a circuit ground.
Claim 56
Dependent Claim
32 words
The electrostatic deposition system according to claim 29, wherein said electrical conducting element comprises a multiplicity of needle points having only their sharp tips protruding from said shield of electrical nonconductive material.
Claim 57
Dependent Claim
107 words
A coating system comprising: a spray gun for aTomizing and ejecting coating material into the atmosphere having a forward end provided with a passage therein said passage having an intake, a shield of electrical nonconducting material surrounding all conducting portions on the forward end of said body, means applying an electrostatic field to the atomized coating material ejected from said spray gun comprising a multiplicity of needles having sharp tips protruding from said shield of electrical nonconductive material, said needles having insulating shields bonded to all their surfaces except their extreme sharp tips, and a high voltage supply connected between said needles and work to be coated.
Claim 58
Dependent Claim
107 words
A coating system comprising: a spray gun for aTomizing and ejecting coating material into the atmosphere having a forward end provided with a passage therein said passage having an intake, a shield of electrical nonconducting material surrounding all conducting portions on the forward end of said body, means applying an electrostatic field to the atomized coating material ejected from said spray gun comprising a multiplicity of needles having sharp tips protruding from said shield of electrical nonconductive material, said needles having insulating shields bonded to all their surfaces except their extreme sharp tips, and a high voltage supply connected between said needles and work to be coated.
Claim 59
Dependent Claim
117 words
A coating system compriding: a spray gun for atomizing and ejecting coating material into the atmosphere having a forward end provided with a substantial mass of electrically conductive material to produce a high capacitance to a circuit ground, means applying an electrostatic field to the atomized coating material ejected from said spray gun connected to said coating material within said spray gun, a container for holding coating material, a high voltage supply having a maximum voltage output connected at said container between coating material in said container and ground, and an electrical nonconductive fluid conduit connecting said container and said intake to transport coating material and electrical current from said container to said spray gun body passage.
Claim 60
Dependent Claim
117 words
A coating system compriding: a spray gun for atomizing and ejecting coating material into the atmosphere having a forward end provided with a substantial mass of electrically conductive material to produce a high capacitance to a circuit ground, means applying an electrostatic field to the atomized coating material ejected from said spray gun connected to said coating material within said spray gun, a container for holding coating material, a high voltage supply having a maximum voltage output connected at said container between coating material in said container and ground, and an electrical nonconductive fluid conduit connecting said container and said intake to transport coating material and electrical current from said container to said spray gun body passage.
Claim 61
Dependent Claim
39 words
A coating system according to claim 51, wherein said material being transported in said fluid conduit provides a resistance between said container and said spray gun not greater than 5,000 ohms per volt provided by said high voltage supply.
Claim 62
Dependent Claim
30 words
A coating system according to claim 51, wherein said mas of electrically conductive material has an effective capacity greater than a metal sphere of a radius of about three centimeters.
Claim 63
Dependent Claim
39 words
A coating system according to claim 53, wherein said material being transported in said fluid conduit provides a resistance between said container and said spray gun not greater than 5,000 ohms per volt provided by said high voltage supply.
Claim 64
Dependent Claim
38 words
A coating system according to claim 51, wherein the electrically conductive material in said spray gun and the coating material in said conduit have an effective capacity greater than a metal sphere of a radius of three centimeters.
Claim 65
Dependent Claim
39 words
A coating system according to claim 55, wherein said material being transported in said fluid conduit provides a resistance between said container and said spray gun not greater than 5,000 ohms per volt provided by said high voltage supply.
Claim 66
Dependent Claim
35 words
A coating system according to claim 51, wherein the ratio of the resistance of the coating material in the conduit to the voltage provided by the high voltage supply is approximately 4 ohms per volt.
Claim 67
Dependent Claim
17 words
A coating system according to claim 51, wherein the ratio is less than 25 ohms per volt.
Claim 68
Dependent Claim
17 words
A coating system according to claim 51, wherein the resistance in the conduit is approximately 250,000 ohms.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |