Spray tip

Patent metadata

Field	Value
Publication number	US-11701670-B2
Application number	US-202017100134-A
Country	US
Kind code	B2
Filing date	Nov 20, 2020
Priority date	Jan 26, 2020
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

A spray tip is configured to atomize thick, viscous fluids. The spray tip includes a pre-orifice piece having an inlet orifice that defines a first restriction in a fluid path through the spray tip. The spray tip also includes a tip piece having an outlet orifice that defines a second restriction in the fluid path. The first and second restrictions are the portions of the fluid path having the smallest flow areas. A cross-sectional area of the outlet orifice is greater than a cross-sectional area of the inlet orifice.

First claim

The invention claimed is:

1. A spray tip for spraying fluid, the spray tip comprising:
a body having a tip bore extending transversely through the body along a flow axis;
a pre-orifice piece located within the tip bore, the pre-orifice piece having a pre-orifice channel extending therethrough, the pre-orifice piece having:
an inlet orifice open on an upstream face of the pre-orifice piece and extending partially axially through the pre-orifice piece from the upstream face;
an expansion portion of the pre-orifice channel extending in a downstream direction from the inlet orifice, the expansion portion widening relative to the inlet orifice as the expansion portion extends in a first axial direction along the flow axis away from the inlet orifice;

a turbulation chamber disposed downstream of the expansion portion to receive flow from the expansion portion, the turbulation chamber having a larger width than an outlet of the expansion portion; and
a tip piece located at least partially within the tip bore, the tip piece spaced in the first axial direction along the tip bore relative to the pre-orifice piece, the tip piece having an outlet orifice formed through an inner domed surface of the tip piece downstream of the turbulation chamber and configured to atomize fluid into a spray fan, the outlet orifice comprising:
an outlet orifice major dimension between a first end of the outlet orifice and a second end of the outlet orifice; and
an outlet orifice minor dimension between a first side of the outlet orifice and a second side of the outlet orifice, the outlet orifice minor dimension smaller than the outlet orifice major dimension such that the outlet orifice is non-circular,

wherein:
the tip piece and the pre-orifice piece together form at least part of a fluid path extending through the tip bore;
the inlet orifice defines a first smallest flow area portion of the fluid path and the outlet orifice define a second smallest flow area portion of the fluid path;
a cross-sectional area of the inlet orifice is less than a cross-sectional area of the outlet orifice; and
a first radial dimension of the inlet orifice is larger than the outlet orifice minor dimension and smaller than the outlet orifice major dimension such that a projection of the inlet orifice overlaps with the inner domed surface through which the outlet orifice is formed.

2. The spray tip of claim 1 , wherein the inlet orifice is defined by a flat circle perpendicular to a flow axis through the tip bore, and wherein the outlet orifice is three-dimensional along the flow axis.

3. The spray tip of claim 2 , wherein a lip of the outlet orifice is curved through three dimensions along a side extending between a first lateral end of the outlet orifice and a second lateral end of the outlet orifice.

4. The spray tip of claim 1 , wherein a functional-flow cross-sectional area of the inlet orifice is smaller than a functional-flow cross-sectional area of the outlet orifice.

5. The spray tip of claim 1 , further comprising:
a spacer disposed axially between the spray tip and the pre-orifice piece, wherein the spacer defines at least a portion of the turbulation chamber disposed between the inlet orifice and the outlet orifice.

6. The spray tip of claim 1 , further comprising:
a retainer disposed within the tip bore and upstream of both of the tip piece and the pre-orifice piece, wherein the retainer engages the body within the tip bore to retain the tip piece and the pre-orifice piece within the tip bore.

7. The spray tip of claim 6 , wherein the tip bore defines a stop and the tip piece includes a shoulder, wherein the shoulder engages the stop to define an axial position of the tip piece.

8. The spray tip of claim 7 , wherein the tip piece includes a domed outlet end extending axially beyond the shoulder.

9. The spray tip of claim 1 , wherein:
the tip piece includes an outlet end having a domed outer surface and the domed inner surface.

10. The spray tip of claim 9 , wherein the outlet orifice is curved along the flow axis and is curved about the flow axis.

11. The spray tip of claim 1 , wherein the inlet orifice further comprises:
a second radial dimension;
wherein the first radial dimension is a major dimension between a first end of the inlet orifice and a second end of the inlet orifice;
wherein the second radial dimension is a minor dimension between a first side of the inlet orifice and a second side of the inlet orifice; and
wherein the first radial dimension is larger than the second radial dimension such that the inlet opening is non-circular.

12. The spray tip of claim 1 , wherein the tip piece includes:
a V-shaped cut extending into an outlet end of the tip piece;
wherein the outlet orifice is defined by the V-shaped cut.

13. The spray tip of claim 1 , wherein the body is a cylindrical body.

14. The spray tip of claim 13 , further comprising:
a handle attached to the cylindrical body.

15. A spray gun comprising:
a gun body;
a handle extending relative to the gun body;
a trigger spaced from the handle and configured to control spraying by the spray gun;
a nozzle holder supported by the gun body; and
the spray tip of claim 1 configured to be disposed at least partially within the nozzle holder.

Assignees

• Graco Minnesota Inc

Inventors

• Stewart Samuel R
• Kinne Robert W

Classifications

• B05B1/048 Primary

  having a flow conduit with, immediately behind the outlet orifice, an elongated cross section, e.g. of oval or elliptic form, of which the major axis is perpendicular to the plane of the jet · CPC title

• B05B9/01

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

• B05B15/534

  by reversing the nozzle relative to the supply conduit · CPC title

• B05B1/046 Primary

  Outlets formed, e.g. cut, in the circumference of tubular or spherical elements · CPC title

• B05B12/002

  Manually-actuated controlling means, e.g. push buttons, levers or triggers (for single units B05B11/00) · CPC title