Nozzle assembly with auxiliary apertures

Patent metadata

Field	Value
Publication number	US-11577262-B2
Application number	US-201615576327-A
Country	US
Kind code	B2
Filing date	May 20, 2016
Priority date	May 27, 2015
Publication date	Feb 14, 2023
Grant date	Feb 14, 2023

Abstract

Provided are nozzle assemblies for a spraying apparatus having an outer wall ( 146 ) having opposed inner and outer surfaces, a central aperture ( 136 ) extending through the outer wall, and a pair of auxiliary apertures ( 158 ) disposed on the outer wall ( 146 ). Each auxiliary aperture is aligned along a respective auxiliary axis ( 162 ) and areas of the inner surface ( 164 ) of the outer wall ( 146 ) adjacent to the auxiliary apertures ( 158 ) are countersunk to define ledges ( 166 ) that are axially symmetric about the auxiliary axes ( 162 ). These assemblies obviate problems associated with rotatable molding pins and also provide the unexpected advantage of providing axial alignment of the air flow profile as air is emitted from the auxiliary apertures.

First claim

What is claimed is:

1. A nozzle assembly for a spraying apparatus comprising:
an inner wall having opposed inner and outer surfaces, the inner surface defining a liquid passageway that extends longitudinally along a liquid axis and terminates in a liquid aperture;
an outer wall extending around the inner wall and having opposed inner and outer surfaces, wherein the outer surface of the inner wall and inner surface of the outer wall collectively define a first air passageway, the first air passageway terminating in an atomizing aperture adjacent the liquid aperture;
a pair of auxiliary apertures extending through the outer wall and in communication with the first air passageway, wherein each auxiliary aperture extends along an auxiliary axis and wherein an area of the inner surface of the outer wall adjacent to each auxiliary aperture is countersunk to define a ledge that is axially symmetric about its auxiliary axis; and
a pair of diametrically opposed air horns protruding past the liquid aperture from the outer wall and defining respective air horn cavities in communication with a second air passageway, each air horn having an external wall and a fan control aperture extending along a fan control axis through the external wall to direct air from the air horn cavity against a stream of liquid droplets discharged from the liquid aperture, each auxiliary axis aligned transverse to a respective fan control axis.

2. The nozzle assembly of claim 1 , wherein each auxiliary aperture has a cylindrical side wall whose length, defined along its longitudinal axis, is generally constant along the circumference of the auxiliary aperture.

3. The nozzle assembly of claim 1 , wherein the ledge is generally planar and aligned along a reference plane.

4. The nozzle assembly of claim 1 , wherein each auxiliary aperture has a certain radius and the ledge has a certain maximum width as measured along a radial direction perpendicular to the auxiliary axis, the certain maximum width ranging from 10 percent to 300 percent of the certain radius.

5. The nozzle assembly of claim 1 , wherein the pair of auxiliary apertures is a first pair and further comprising one or more additional pairs of auxiliary apertures extending through the outer wall and each having substantially the same features as the first pair.

6. A method of aligning auxiliary air flow through the nozzle assembly of claim 1 , the method comprising:
discharging a liquid from the liquid aperture in a conical stream of liquid droplets while directing air from the fan control apertures against the discharged liquid from opposing directions to flatten the conical stream of liquid droplets; and
directing air from the pair of auxiliary apertures to modify the air flowing from the fan control apertures, wherein each ledge improves axial alignment of the air flow external to its respective auxiliary aperture.

7. The method of claim 6 , wherein air flowing into each auxiliary aperture is directed along directions parallel to the inner surface of the outer wall.

8. The method of claim 6 , wherein the air discharged from each auxiliary aperture has a flow field that is generally symmetric about its respective auxiliary axis.

9. A spraying apparatus comprising:
the nozzle assembly of claim 1 ; and
a spray gun platform releasably coupled to the nozzle assembly.

10. An air cap for a nozzle assembly of a spraying apparatus comprising:
an outer wall having opposed inner and outer surfaces;
a central aperture extending through the outer wall;
a pair of auxiliary apertures disposed on the outer wall, each auxiliary aperture aligned along a respective auxiliary axis, wherein an area of the inner surface of the outer wall adjacent to the auxiliary aperture is countersunk to define a ledge that is axially symmetric about the auxiliary axis; and
a pair of diametrically opposed air horns protruding from the outer wall past the central aperture and defining respective air horn cavities, each air horn having an external wall and a fan control aperture extending along a fan control axis through the external wall to direct air from the air horn cavity against a conical stream of liquid droplets discharged from the central aperture, wherein each auxiliary axis is oriented transverse to a respective fan control axis.

11. A nozzle assembly for a spraying apparatus comprising:
an inner wall having opposed inner and outer surfaces, the inner surface defining a liquid passageway that extends longitudinally along a liquid axis and terminates in a liquid aperture;
an outer wall extending around the inner wall and having opposed inner and outer surfaces, wherein the outer surface of the inner wall and inner surface of the outer wall collectively define a first air passageway, the first air passageway terminating in an atomizing aperture adjacent the liquid aperture;
a pair of auxiliary apertures extending through the outer wall and in communication with the first air passageway, wherein each auxiliary aperture extends along an auxiliary axis and wherein an area of the inner surface of the outer wall adjacent to each auxiliary aperture is countersunk to define a ledge that is axially symmetric about its auxiliary axis, wherein the ledge is generally planar and aligned along a reference plane.

12. A method of aligning auxiliary air flow through the nozzle assembly of claim 11 , the method comprising:
discharging a liquid from the liquid aperture in a conical stream of liquid droplets while directing air from the fan control apertures against the discharged liquid from opposing directions to flatten the conical stream of liquid droplets; and
directing air from the pair of auxiliary apertures to modify the air flowing from the fan control apertures, wherein each ledge improves axial alignment of the air flow external to its respective auxiliary aperture.

13. The method of claim 12 , wherein air flowing into each auxiliary aperture is directed along directions parallel to the inner surface of the outer wall.

14. The method of claim 12 , wherein the air discharged from each auxiliary aperture has a flow field that is generally symmetric about its respective auxiliary axis.

15. A spraying apparatus comprising:
the nozzle assembly of claim 11 ; and
a spray gun platform releasably coupled to the nozzle assembly.

16. The nozzle assembly of claim 1 , wherein a shape of the ledge is at least partially curved where an entrance to the auxiliary apertures has an annular edge defined at the interface between a cylindrical side wall and the ledge, the annular edge having a corner radius of at least 1 percent the radius of the auxiliary aperture.

Assignees

• 3M Innovative Properties Company

Inventors

• Scheibner John B
• Duncan Brian E
• Yorkgitis Elaine M
• Erickson Ryan D

Classifications

• B05B7/0807

  to form intersecting jets · CPC title

• B05B7/066 Primary

  with an inner liquid outlet surrounded by at least one annular gas outlet · CPC title

• B05B7/0861

  with one single jet constituted by a liquid or a mixture containing a liquid and several gas jets (B05B7/0815 takes precedence) · CPC title

• B05B7/0815 Primary

  with at least one gas jet intersecting a jet constituted by a liquid or a mixture containing a liquid for controlling the shape of the latter · CPC title