Powder spray gun for quick color changes systems

• US 4,815,666 A
• Filed: 09/21/1987
• Issued: 03/28/1989
• Est. Priority Date: 09/21/1987
• Status: Expired due to Fees

• Current Assignee: Nordson Corporation
• Original Assignee: Nordson Corporation
• Inventors: Traylor, John C., Hollstein, Thomas E., Gacka, Mark
• Primary Examiner(s): Kashnikow, Andres
• Assistant Examiner(s): Merritt, Karen B.
• Application Number:
  US07/099,495
• Time in Patent Office: 554 Days
• Field of Search: 239/3, 239/11, 239/600, 239/707, 239/697, 239/704, 239/706, 239/456-458, 239/505, 239/513-515
• US Class Current: 239/697
• CPC Class Codes: B05B 5/032 for spraying particulate materials

Abstract

A powder spray gun for use in spraying particulate powder material of different colors is constructed of a number of individual parts which are quickly and easily disassembled from one another so that each part which comes into contact with particulate powder material can be individually cleaned in changing over from one powder to another. The powder spray gun comprises a mounting block which carries a rearward barrel member and a powder inlet tube, a forward barrel member connected to the rearward barrel member, a nozzle and pattern adjustment sleeve both carried on the forward barrel member and an electrostatic cable assembly received within a barrel liner which extend axially along the length of the spray gun. All but one of the connections between these parts are made by O-rings which frictionally engage facing surfaces of the parts so that they are easily pulled apart, cleaned by a jet of air or the like and then reassembled in preparation for spraying another color of particulate powder material.

Claims

1. A powder spray gun adapted for easy assembly and disassenbly, comprising:

a mounting block having an inlet sleeve, a cavity and means for mounting to a support rod;

a barrel member releasably mounted within said cavity of said mounting block, said barrel member being formed with a throughbore and a powder inlet passageway intersecting said throughbore;

a powder inlet tube releasably mounted within said powder inlet passageway of said barrel member, said powder inlet tube being adapted to connect to a supply line from a source of particulate powder material;

a cable assembly including a cable liner having a hollow interior and an electrostatic cable mounted within at least a portion of said hollow interior of said cable liner, one end of said cable assembly being mounted to said inlet sleeve of said mounting block and extending outwardly from said mounting block through said cavity thereof and into said throughbore of said barrel member;

said barrel member being slidably disengageable from said cable assembly and said mounting block, respectively while said mounting block and cable assembly remain assembled.

2. A powder spray gun adapted for easy assembly and disassembly, comprising:

a mounting block formed with an inlet sleeve, a cavity and means for mounting to a support rod;

a barrel member slidably and frictionally mounted within said cavity of said mounting block, said barrel member being formed with a throughbore defining an inner wall and a powder inlet passageway intersecting said througbore, said powder inlet passageway being adapted to be connected to a source of particulate powder material;

a barrel liner having a throughbore and an outer wall, said barrel liner being slidably and frictionally mounted within said throughbore of said barrel member forming a powder flow passageway between said outer wall of said barrel liner and said inner wall of said barrel member;

a cable assembly including a cable liner having a hollow interior and an electrostatic cable mounted within said hollow interior of said cable liner, one end of said cable assembly being mounted to said inlet sleeve of said mounting block and extending outwardly from said mounting block through said cavity thereof and into said throughbore of said barrel member;

a deflector slidably and frictionally mounted to said outer end of said cable assembly, said deflector having an electrode in electrical contact with the electrostatic cable carried within said cable liner of said cable assembly;

said deflector, said barrel member and said barrel liner being slidably disassembled for cleaning of particulate powder material therefrom, while said cable assembly and said mounting block remain assembled.

3. A powder spray gun adapted for easy assembly and disassembly, comprising:

a mounting block formed with an inlet sleeve, a cavity and means for mounting to a support rod;

a cable assembly including a cable liner having a hollow interior and an electrostatic cable mounted within said hollow interior of said cable liner, one end of said cable assembly being mounted to said inlet sleeve of said mounting block and extending outwardly from said mounting block through said cavity thereof;

a rearward barrel member slidably and frictionally mounted within said cavity of said mounting block, said rearward barrel member being formed with a throughbore which receives said cable assembly and a powder inlet passageway intersecting said throughbore;

a powder delivery tube adapted to be connected to a source of particulate powder material, said powder delivery tube being carried within said powder inlet passageway of said rearward barrel member;

a forward barrel member connected to said rearward barrel member, said forward barrel member being formed with an outer surface and a throughbore which receives said cable assembly;

a barrel liner having a throughbore which receives said cable assembly, said barrel liner being slidably and frictionally mounted at one end by said rearward barrel member and extending outwardly therefrom within said throughbore of each said forward and rearward barrel members;

a nozzle slidably and frictionally mounted on said outer surface of said forward barrel member, said nozzle being formed with a throughbore which receives said cable assembly;

a cable liner mount slidably and frictionally mounted on said outer surface of said forward barrel member and extending into said throughbore of said nozzle, said cable liner mount being formed with a throughbore defining an inner wall which supports the other end of said cable assembly;

a deflector slidably and frictionally mounted to said other end of said cable assembly, said deflector having an electrode in electrical contact with the electrostatic cable carried within said cable liner of said cable assembly.

4. A powder spray gun adapted for easy assembly and disassembly, comprising:

a mounting block formed with an inlet sleeve, a cavity and means for mounting to a support rod;

a cable assembly including a cable liner having a hollow interior and an electrostatic cable mounted within said hollow interior of said cable liner, one end of said cable assembly being mounted to said inlet sleeve of said mounting block and extending outwardly from said mounting block through said cavity thereof;

a rearward barrel member carried within said cavity of said mounting block, said rearward barrel member being formed with a throughbore which receives said cable assembly and a powder inlet passageway intersecting said throughbore;

a powder delivery tube adapted to be connected to a source of particulate powder material, said powder delivery tube being carried within said powder inlet passageway of said rearward barrel member;

a forward barrel member connected to said rearward barrel member, said forward barrel member being formed with an outer surface and a throughbore which receives said cable assembly;

a barrel liner having a throughbore which receives said cable assembly, said barrel liner being carried at one end by said rearward barrel member and extending outwardly therefrom within said throughbore of each said forward and rearward barrel members;

a nozzle carried on said outer surface of said forward barrel member, said nozzle being formed with a throughbore which receives said cable assembly;

a cable liner mount carried on said outer surface of said forward barrel member and extending into said throughbore of said nozzle, said cable liner mount being formed with a throughbore defining an inner wall which supports the other end of said cable assembly;

a deflector mounted to said other end of said cable assembly, said deflector having an electrode in electrical contact with the electrostatic cable carried within said cable liner of said cable assembly.

5. The powder spray gun of claim 4 including a pattern adjustment sleeve carried on said outer surface of said forward barrel member, said pattern adjustment sleeve being formed with a throughbore which receives said nozzle.

6. The powder spray gun of claim 5 in which said pattern adjustment sleeve has an inner wall formed by said throughbore, said inner wall being formed with at least one groove which mounts an O-ring, said pattern adjustment sleeve being slid onto said outer surface of said forward barrel member so that said O-ring engages said outer surface to retain said pattern adjustment sleeve on said forward barrel member.

7. The powder spray gun of claim 4 in which said powder delivery tube is positioned on an angle of about 23°

relative to the longitudinal axis of said throughbore formed in said rearward barrel member.

8. The powder spray gun of claim 4 in which the diameter of said forward barrel member increases upstream from said cable liner mount to decrease the velocity of particulate powder material flowing through said forward barrel member.

9. The powder spray gun of claim 4 in which said cavity forms an inner wall in said mounting block, said rearward barrel member including an outer surface which carries at least one O-ring, said O-ring engaging said inner wall of said cavity of said mounting block for slidably retaining said rearward barrel member within said cavity.

10. The powder spray gun of claim 4 in which said mounting block is formed with a stepped bore forming an inner wall and an annular seat, said one end of said barrel liner being mounted upon said seat formed in said mounting block, an O-ring being mounted within a groove formed in said inner wall of said mounting block in a position wherein said O-ring engages said barrel liner to retain said barrel liner upon said seat.

11. The powder spray gun of claim 4 in which said forward barrel member includes a forward end formed with at least one annular groove which mounts an O-ring, said nozzle being positioned over said forward end of said forward barrel member so that said O-ring engages the wall formed by said throughbore in said nozzle to retain said nozzle on said forward barrel member.

12. The powder spray gun of claim 4 in which said throughbore in said nozzle forms an annular shoulder, said cable liner mount having a forward end which engages said annular shoulder of said nozzle to retain said cable liner mount on said forward end of said forward barrel member.

13. A powder spray gun for spraying particulate powder material, comprising:

a mounting block;

a cable assembly including a cable liner having a hollow interior and an electrostatic cable mounted within said hollow interior of said cable liner;

a gun barrel carried by said mounting block, said gun barrel being formed with a powder flow passageway and a powder inlet passageway which intersects said powder flow passageway at an angle of less than about 30°

relative to the longitudinal axis of said powder flow passageway;

a hollow barrel liner which receives said cable assembly, said barrel liner and cable assembly being mounted within said powder flow passageway of said gun barrel;

a powder delivery tube connected to said powder inlet passageway and adapted to connect to a source of air-entrained particulate powder material, said powder delivery tube transmitting particulate powder material to said powder inlet passageway and into said powder flow passageway at said angle of less than 30°

so that the particulate powder material is thoroughly mixed about said barrel liner within said powder flow passageway.

14. The powder spray gun of claim 13 in which said angle of said powder inlet passageway is about 23°

.