Claims
- 1. A spray gun for spraying coating material, which comprises:
- a housing including a body;
- a spindle mounted for rotation within the body, the spindle having a rotating tubular passageway therethrough for the flow of coating material path, the passageway rotating with the spindle, the passageway having first and second ends;
- a nonrotating flow tube through which powder flows into the rotating tubular passageway, one end of the flow tube extending partially into the first end of the passageway and spaced within the passageway from the second end, a gap being formed between the nonrotating flow tube and the rotatable spindle, the gap communicating with a supply of pressurized air whereby pressurized air escapes through the gap to provide a rotary seal between the tube and the spindle;
- a flexible sealing member mounted on one of the spindle and the flow tube and capable of engaging the other of the spindle and the flow tube to seal the gap to prevent material in the passageway from entering the gap, the sealing member urged away from engagement by the pressurized air;
- a distributor communicating with the passageway and attached for rotation with the spindle, coating material flowing from the passageway into the distributor to be sprayed from the gun; and
- a drive mechanism located within the body and connected to rotate the spindle and the distributor.
- 2. A spray gun as in claim 1, wherein the sealing member is mounted on the rotating spindle and engages the nonrotating flow tube.
- 3. A spray gun as in claim 1, comprising in addition, a second sealing member mounted to engage the spindle.
- 4. A spray gun as in claim 1, wherein spindle and the distributor rotate about the central longitudinal axis of the body, and wherein the drive mechanism is located along an axis radially spaced from the longitudinal axis of the body.
- 5. A spray gun as in claim 1, comprising in addition a plurality of discrete electrodes mounted to extend from the exterior of the housing, the electrodes located radially beyond the outer diameter of the distributor.
- 6. A powder spray gun, which comprises:
- a housing including a body, the body including a chamber which is connected to a supply of pressurized air;
- a powder flow path extending through the body to a powder outlet, the powder flow path generally located along the central longitudinal axis of the body;
- a rotatable powder distributor located at the powder outlet;
- a spindle mounted in the chamber and connected for rotation with the distributor, the spindle having a central passageway forming a portion of the powder flow path;
- at least one bearing assembly supporting the spindle for rotation;
- a nonrotating flow tube through which powder flows into the passageway, a gap being formed between the nonrotating flow tube and the rotatable spindle, the gap communicating with the chamber whereby pressurized air from the chamber escapes through the gap to provide a rotary seal between the tube and the spindle and prevents powder from flowing into the bearing assembly;
- a flexible sealing member mounted on one of the spindle and the flow tube and capable of engaging the other of the spindle and the flow tube to seal the gap to prevent material in the passageway from entering the gap, the sealing member urged away from engagement by pressurized air from the chamber; and
- a drive mechanism located within the housing along an axis radially spaced from the longitudinal axis of the body and connected to the distributor to rotate the distributor at speeds of from 0 to 2,500 rpm.
- 7. A powder spray gun as in claim 6, comprising in addition a latching mechanism mounted in the body and capable of engaging the spindle to selectively prevent the spindle from rotating.
- 8. A powder spray gun as in claim 6, comprising in addition a plurality of discrete electrodes mounted to extend from the exterior of the housing, the electrodes located radially beyond the outer diameter of the distributor.
- 9. A powder spray gun as in claim 6, wherein the powder flow path is substantially straight through the body and without obstacles or spacer elements extending through the flow path.
- 10. A spray gun for spraying coating material which comprises:
- a housing including a body, the body including a chamber which is connected to a supply of pressurized air;
- a spindle mounted for rotation within the body, the spindle having a rotating tubular passageway therethrough for the flow of coating material, the passageway rotating with the spindle, the passageway having first and second ends;
- at least one bearing assembly supporting the spindle for rotation;
- a nonrotating flow tube through which the coating material flows into the rotating tubular passageway, one end of the flow tube extending partially into the first end of the passageway and spaced within the passageway from the second end, a gap being formed between the nonrotating flow tube and the rotatable spindle, the gap communicating with the chamber whereby pressurized air from the chamber escapes through the gap to provide a rotary seal between the tube and the spindle and prevents the coating material from entering the bearing assembly;
- a flexible sealing member mounted on one of the spindle and the flow tube and capable of engaging the other of the spindle and the flow tube to seal the gap to prevent material in the passageway from entering the gap, the sealing member urged away from engagement by pressurized air from the chamber;
- a distributor communicating with the passageway and attached for rotation with the spindle, coating material flowing from the passageway into the distributor to be sprayed from the gun; and
- a drive mechanism located within the body and connected to rotate the spindle and the distributor at speeds of from 0 to 2,500 rpm.
- 11. A spray gun as in claim 10, wherein spindle and the distributor rotate about the central longitudinal axis of the body, and wherein the drive mechanism is located along an axis radially spaced from the longitudinal axis of the body.
- 12. A spray gun as in claim 10, comprising in addition a plurality of discrete electrodes mounted to extend from the exterior of the housing, the electrodes located radially beyond the outer diameter of the distributor.
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation in part of application Ser. No. 08/444,785, filed May 19, 1995 now abandoned.
US Referenced Citations (5)
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
444785 |
May 1995 |
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