Hand held paint spray gun with top mounted paint cup

• US 5,582,350 A
• Filed: 10/31/1995
• Issued: 12/10/1996
• Est. Priority Date: 04/19/1994
• Status: Expired due to Term

• Current Assignee: Finishing Brands Holdings Inc. (Carlisle Cos., Inc.)
• Original Assignee: Ransburg Corp. (Illinois Tool Works Inc.)
• Inventors: Wisniewski, Ralph A., Kosmyna, Michael J., Charpie, Mark E.
• Primary Examiner(s): Morris, Lesley D.
• Application Number:
  US08/551,167
• Time in Patent Office: 406 Days
• Field of Search: 239/345, 239/346, 239/379, 239/340, 239/318, 239/311, 239/DIG. 14, 239/289, 222/105, 222/83.5, 220/293, 220/300, 215/321
• US Class Current: 239/345
• CPC Class Codes: B05B 15/55 using cleaning fluids
• CPC Class Codes: B05B 7/2413 with means for changing the position or the orientation of the container relative to the spray apparatus
• CPC Class Codes: B05B 7/2478 Gun with a container which, in normal use, is located above the gun
• CPC Class Codes: B05B 7/2481 with a flexible container for liquid or other fluent material
• CPC Class Codes: Y10S 239/14 Paint sprayers

Abstract

A hand held paint spray gun having a top mounted paint cup which extends from the rear of a gun body at an angle of 30°±10° to an axis about which the atomized paint is discharged. A retainer ring secures a lid on the cup. The lid seals to both the inside and the outside of the cup. The double seals reduce the risk of paint leakage. Preferably, the gun operates with suction paint feed which is augmented by gravity feed when paint in the cup is located above a nozzle assembly on the gun. To facilitate cleaning and to allow the gun to spray in an upward direction, the paint may be sealed in a collapsible closed bag located in the cup. With the closed bag and the suction feed, the gun will operate when aimed in all directions. The gun is easily cleaned by forcing solvent from the nozzle assembly back into the bag and disposing of the bag containing any remaining paint and the used solvent.

Claims

1. In a hand held paint spray gun including a body, a nozzle assembly mounted to a front end of said body and a handle extending from adjacent a rear end of said body, said gun having an atomization air supply hose connected to said handle, said nozzle assembly atomizing and discharging paint about a spray axis during operation, the improvement comprising a paint cup having first and second spaced ends, means securing said first paint cup end to said gun body adjacent said rear gun body end, said paint cup extending from said gun body opposite said gun handle past the rear end of said gun body along a central axis forming an angle of from 25°

to 35°

to said spray axis, and a tube connected for delivering paint from said cup to said nozzle assembly, wherein said paint cup has a lid secured to said second paint cup end extending substantially perpendicular to the paint cup axis, and a vent in said lid spaced on said lid from said paint cup axis in a direction away from said pray axis.

2. A hand held paint spray gun, as set forth in claim 1, and wherein said cup axis extends at an angle of substantially 30°

to said spray axis.

3. In a hand held paint spray gun including a body, a nozzle assembly mounted to a front end of said body and a handle extending from adjacent a rear end of said body, said gun having an atomization air supply hose connected to said handle, said nozzle assembly atomizing and discharging paint about a spray axis during operation, the improvement comprising a paint cup, means securing said paint cup to said gun body adjacent said rear end, said paint cup extending from said gun body opposite said gun handle past the rear end of said gun body along an axis forming an angle of from 25°

to 35°

to said spray axis, and a tube connected for delivering paint from said cup to said nozzle assembly, and wherein said cup has an annular open end, a tapered annular exterior surface adjacent said open end and a tapered annular interior surface adjacent said open end, said tapered exterior and interior surfaces forming oppositely directed angles of from 5°

to 15°

to said cup axis, a lid having an annular groove for receiving said open cup end, said lid groove having two spaced tapered annular surfaces which are complementary to and engage with surface to surface contact said exterior and interior cup surfaces, said lid groove having a bottom which is spaced from said open cup end when said tapered cup surfaces engage said tapered groove surfaces, a retainer ring engaging a perimeter of said lid, means for releasably connecting said retainer ring to said cup to secure said lid over said open cup end, said lid separately sealing to both said exterior surface and said interior surface of said cup when said lid is secured to said cup, and a vent in said lid.

4. In a hand held paint spray gun including a body, a nozzle assembly mounted to a front end of said body and a handle extending from adjacent a rear end of said body, said gun having an atomization air supply hose connected to said handle, said nozzle assembly atomizing and discharging paint about a spray axis during operation, the improvement comprising a paint cup, means securing said paint cup to said gun body adjacent said rear end, said paint cup extending from opposite said gun handle past the rear end of said gun body along an axis forming an angle of from 25°

to 35°

to said spray axis, a tube connected for delivering paint from said cup to said nozzle assembly, said cup having an annular open end, a tapered annular exterior surface adjacent said open end and a tapered annular interior surface adjacent said open end, said tapered exterior and interior surfaces forming oppositely directed angles of from 5°

to 15°

to said cup axis, a lid having an annular groove for receiving said open cup end, a retainer ring engaging a perimeter of said lid, means for releasably connecting said retainer ring to said cup to secure said lid over said open cup end, said lid separately sealing to both said exterior surface and said interior surface of said cup when said lid is secured to said cup, and a vent in said lid comprises a tubular projection extending from said lid, said projection having an interior closed at one end by said lid and open at an opposite end, a removable cap closing said open projection end, a vent opening centered in said cap, and a pair of spaced vent openings in said cap between said projection interior and the interior of said paint cup, said spaced vent openings being located wherein any paint in said projection interior drains through one of said spaced openings into said cup when said gun is oriented with said spray axis horizontal and such paint drains through the other of said spaced openings into said cup when said gun is directed downwardly with said spray axis vertical.

5. A hand held paint spray gun, as set forth in claim 4 wherein said lid has a surface facing the interior of said cup when said lid is secured to said cup, and wherein said spaced openings are chamfered at said lid surface.

6. In a hand held paint spray gun including a body, a nozzle assembly mounted to a front end of said body and a handle extending from adjacent a rear end of said body, said gun having an atomization air supply hose connected to said handle, said nozzle assembly atomizing and discharging paint about a spray axis during operation, the improvement comprising a paint cup, means securing said paint cup to said gun body adjacent said rear end, said paint cup extending from opposite said gun handle past the rear end of said gun body along an axis forming an angle of from 25°

to 35°

to said spray axis, and a tube connected for delivering paint from said cup to said nozzle assembly and wherein said means securing said paint cup to said gun body adjacent said rear end comprises first and second spaced brackets, a first pin projecting from said first bracket towards said second bracket, a second pin projecting from said second bracket towards said first bracket, said pins engaging holes on said gun body, said first bracket having an end extending past said first pin, and means for securing said extended first bracket end to said gun body.

7. In a hand held paint spray gun including a body, a nozzle assembly mounted to a front end of said body and a handle extending from adjacent a rear end of said body, said gun having an atomization air supply hose connected to said handle, said nozzle assembly atomizing and discharging paint about a spray axis during operation, the improvement comprising a paint cup, means securing said paint cup to said gun body adjacent said rear end, said paint cup extending from said gun body opposite said gun handle past the rear end of said gun body along an axis forming an angle of from 25°

to 35°

to said spray axis, and a tube connected for delivering paint from said cup to said nozzle assembly, and wherein paint flows to said gun through suction feed, and further including a disposable flexible bag located in said paint cup, said bag having an opening adjacent one end and a sealed zipper closure adjacent an opposite end, means connecting said bag opening in fluid communications to deliver paint to said tube, said bag collapsing as paint is delivered from said bag to said gun.

8. In combination with a hand held paint spray gun, a paint cup mounted on said spray gun, tube means for delivering paint from said paint cup to said spray gun, a disposable flexible bag located in said paint cup, said bag having an opening adjacent one end and a sealed zipper closure adjacent an opposite end, means connecting said bag opening in fluid communications to deliver paint to said tube, said bag collapsing as paint is delivered from said bag to said gun.

9. A hand held paint spray gun, as set forth in claim 8, and wherein said tube is made of polytetrafluoroethylene.

10. A hand held paint spray gun, as set forth in claim 8, and wherein said connecting means comprises a bushing having an end passing through said bag opening, said bushing having an enlarged diameter flange located in said bag, said flange retaining said bushing in said bag opening.

11. In a hand held paint spray gun having a top mounted paint cup and a lid closing said paint cup, said lid having a vent opening including a vent passage through said lid communicating with a chamber closed by a cap having a central vent opening spaced from said vent passage, the improvement wherein said vent passage comprises a pair of spaced vent passages communicating between said paint cup and said chamber, and wherein one of said passages is located at the lowest position in said chamber when said spray gun is aimed with an axis about which paint is sprayed oriented horizontal and the other of said passages is located at the lowest position in said chamber when said spray gun is aimed downwardly to spray about a vertical axis.

12. A hand held paint spray gun, as set forth in claim 11, wherein said lid has a surface facing an interior of said cup when said lid is secured to said cup, and wherein said spaced openings are chamfered at said lid surface.

13. A method for operating it hand held paint spray gun of the type in which a flow of atomization air through said spray gun when said spray gun is triggered creates suction for feeding paint to said spray gun, said method comprising the steps of:

a) lining a paint cup mounted on said gun with a disposable flexible bag having a sealed zipper closure at one end and a paint outlet connected to deliver paint to said gun;

b) placing a volume of paint in said bag and sealing said zipper closure, said bag having a volume of air entrapped above the paint in said bag;

c) while positioning said spray gun with said paint outlet located above the paint in said bag, triggering said spray gun to create suction feed to draw the entrapped air from said bag; and

d) using said spray gun to spray paint from said bag.

14. A method for operating a hand held suction feed paint spray gun, as set forth in claim 13, and, after spraying is completed, further including the steps of:

e) interrupting the flow of atomization air to said spray gun;

f) while triggering said spray gun, forcing solvent to flow from a nozzle on said spray gun back into said bag to flush paint from said spray gun; and

g) disposing of said bag.

15. A method for securing a bag in a paint cup having an outlet opening, said bag having a zipper closure for sealing said, bag, said method comprising the steps of:

a) inserting a tool having a stepped cylindrical exterior surface into an opening through a bushing until said tool step abuts said bushing, said tool having a section extending through said bushing and tapering to a sharp end, and said bushing having a tubular end and an enlarged diameter flange adjacent said tubular end;

b) piercing an opening in a bottom region of said bag from the inside of said bag with said tool end;

c) forcing said tool end, said tapered section and said bushing end through the pierced bag opening until said bushing flange abuts said bag;

d) manipulating said tool to insert said bushing end into said paint cup outlet; and

e) withdrawing said tool from said bushing and said bag.

16. A method for operating a paint spray gun having a paint atomizing nozzle assembly comprising the steps of:

a) delivering paint from a disposable bag to said spray gun nozzle assembly for spraying;

b) subsequent to completion of spraying, forcing a flow of paint cleaning solvent in a reverse direction from the nozzle assembly to the disposable bag for cleaning said spray gun and collecting the used solvent in the disposable bag; and

c) disposing of the disposable bag and its contents.

17. A disposable liner for a paint cup secured to a spray gun, said paint cup having a bottom opening through which paint is withdrawn during spraying, said liner comprising a flexible paint receiving bag having first and second ends, a zipper closure sealing said bag first end, a paint discharge opening adjacent said bag second end, and means for securing said bag to the paint cup with said paint discharge opening connected to deliver paint to the cup bottom opening.

18. A disposable liner for a paint cup, as set forth in claim 17, and wherein said securing means comprises a bushing having a tubular end and an enlarged diameter flange adjacent said tubular end, said tubular end having an exterior diameter greater than the diameter of said paint discharge opening in said bag, and wherein said bushing is secured to said bag with said enlarged diameter flange located inside said bag and said tubular end extending through said paint discharge opening in said bag, whereby the resiliency of said bag retains said bushing in said paint discharge opening.

19. Apparatus for securing a flexible liner bag in a paint cup, such paint cup having an opening through which paint flows, comprising a bushing having a tubular end and an enlarged diameter flange, said tubular end having an exterior diameter sized for a friction fit in the paint cup opening, said bushing having an interior opening of a predetermined diameter extending through said tubular end and said flange, and a tool having a portion of a diameter greater than said predetermined diameter of said bushing opening, said tool having a first end and having a second end of a diameter for passing through said tubular bushing opening, whereby said second tool end is free to pass through said bushing opening until said greater diameter portion abuts said bushing.

20. The apparatus for securing a flexible liner bag in a paint cup, as set forth in claim 19, and wherein said tool second end has a length greater than the length of said bushing opening whereby said second end projects from said bushing opening when inserted through said bushing opening with said greater diameter portion abutting said bushing, and wherein the portion of said second end which projects from said bushing opening has means for piercing a hole in a flexible liner bag.

21. A disposable liner for a paint cup secured to a spray gun, said paint cup having a bottom opening through which paint is withdrawn during spraying, said liner comprising a flexible paint receiving bag having first and second ends, a fluid tight revealable closure sealing said bag first end, a paint discharge opening adjacent said bag second end, and means for securing said bag to the paint cup with said paint discharge opening connected to deliver paint to the cup bottom opening.

22. A disposable liner for a paint cup, as set forth in claim 21, and wherein said securing means comprises a bushing having a tubular end and an enlarged diameter flange adjacent said tubular end, said tubular end having an exterior diameter greater than the diameter of said paint discharge opening in said bag, and wherein said bushing is secured to said bag with said enlarged diameter flange located inside said bag and said tubular end extending through said paint discharge opening in said bag, whereby the resiliency of said bag retains said bushing in said paint discharge opening.

23. A disposable liner for a paint cup, as set forth in claim 21, and wherein said closure at said first bag end is a zipper closure.