Liquid dispensing applicators having backpressure control devices, and related methods

Patent metadata

Field	Value
Publication number	US-10150134-B2
Application number	US-201815934969-A
Country	US
Kind code	B2
Filing date	Mar 24, 2018
Priority date	Mar 9, 2015
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

An applicator for dispensing liquid material onto a substrate includes a body, a valve module, and a backpressure control device having a device passage. The body includes an inlet passage, a dispensing outlet passage, and a recirculation outlet passage. The valve module has a dispensing mode and a recirculation mode, and directs the liquid material through the dispensing outlet passage in the dispensing mode and directs the liquid material through the recirculation outlet passage in the recirculation mode. The backpressure control device directs the liquid material through the device passage in the recirculation mode such that a backpressure of the liquid material in the recirculation mode is substantially equal to a backpressure of the liquid material in the dispensing mode. A method of adjusting a backpressure experienced by liquid material is also disclosed.

First claim

What is claimed is:

1. An applicator for dispensing liquid material onto a substrate, said applicator comprising:
a body including:
an inlet passage for receiving liquid material,
a dispensing outlet passage for directing the liquid material toward the substrate, and
a recirculation outlet passage for recirculating the liquid material;

a valve module having a dispensing mode and a recirculation mode, wherein said valve module directs the liquid material through said dispensing outlet passage in said dispensing mode, and directs the liquid material through said recirculation outlet passage in said recirculation mode; and
a backpressure control device configured to adjust backpressure experienced by the liquid material, the backpressure control device having a device passage that communicates with said recirculation outlet passage,
wherein said backpressure control device includes a device portion that is configured to adjust a volume of said device passage such that a backpressure experienced by the liquid material in said recirculation mode is substantially equal to a backpressure experienced by the liquid material in said dispensing mode.

2. The applicator of claim 1 , wherein the device portion is movable relative to said body to adjust the volume of said device passage.

3. The applicator of claim 1 , wherein:
said backpressure control device includes a valve having a needle and a port that receives said needle, said needle and said port forming said device passage therebetween.

4. The applicator of claim 3 , wherein said needle includes a tapered portion, said port includes a tapered bore that receives said tapered portion, and said device passage includes a tapered annular space formed between said tapered portion of said needle and said tapered bore of said port.

5. The applicator of claim 1 , wherein said backpressure control device is fixed relative to said body such that said device passage has a fixed volume.

6. The applicator of claim 1 , wherein said backpressure control device includes an insert received within at least a portion of said recirculation outlet passage, said insert having a bore that forms said device passage.

7. The applicator of claim 1 , wherein said valve module includes a valve stem that is movable between an open position in which said valve module operates in said dispensing mode and a closed position in which said valve module operates in said recirculation mode.

8. The applicator of claim 7 , wherein said backpressure control device includes a ring that encircles said valve stem, said ring having a radially outer wall, a radially inner wall, and a plurality of circumferentially spaced bores extending between said radially inner wall and said radially outer wall, and
wherein said plurality of circumferentially spaced bores forms at least a portion of said device passage.

9. The applicator of claim 8 , wherein:
said ring further includes an outer annular groove formed on said radially outer wall and an inner annular groove formed on said radially inner wall, said outer annular groove at least partially forming an outer annular chamber and said inner annular groove at least partially forming an inner annular chamber, and
said device passage includes said outer annular chamber and said inner annular chamber.

10. A method of adjusting a backpressure experienced by liquid material in an applicator including a body having an inlet passage, a dispensing outlet, and a recirculation outlet, a valve module having a dispensing mode for dispensing the liquid material through said dispensing outlet and a recirculation mode for recirculating liquid material through said recirculation outlet, and a backpressure control device having a device passage and including a device portion that is movable, the method comprising:
moving the device portion of the backpressure control device to adjust a volume of said device passage such that the backpressure experienced by the liquid material in said recirculation mode is substantially equal to a backpressure experienced by the liquid material in said dispensing mode.

11. The method of claim 10 , further comprising receiving the liquid material through the inlet passage formed in the body.

12. The method of claim 11 , further comprising directing the liquid material from the inlet passage toward the dispensing outlet in the dispensing mode.

13. The method of claim 11 , further comprising directing the liquid material from the inlet passage toward the recirculation outlet in the recirculation mode.

14. The method of claim 10 , wherein moving the device portion of the backpressure control device to adjust the volume of said device passage comprises moving the device portion in a first direction to increase the backpressure experienced by the liquid material and/or moving the device portion in a second direction to decrease the backpressure experienced by the liquid material.

15. The method of claim 14 , wherein the second direction is opposite the first direction.

16. The method of claim 15 , wherein the first direction is towards the body and the second direction is away from the body.

17. The method of claim 14 , wherein moving the device portion in the first direction to increase the backpressure experienced by the liquid material comprises decreasing the volume of said device passage.

18. The method of claim 14 , wherein moving the device portion in the second direction to decrease the backpressure experienced by the liquid material comprises increasing the volume of said device passage.

Assignees

• Nordson Corp

Inventors

• Saine Joel E

Classifications

• B05B7/0416

  with arrangements for mixing one gas and one liquid · CPC title

• B05C5/0279

  independently, e.g. individually, flow controlled · CPC title

• B05B14/00 Primary

  Arrangements for collecting, re-using or eliminating excess spraying material (arrangements integral with nozzles B05B1/28) · CPC title

• B05C5/0237 Primary

  Fluid actuated valves · CPC title

• B05B9/01

  Spray pistols, {discharge devices}(B05B9/03 takes precedence) · CPC title