US3734406A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for producing a flat fan paint spray pattern
Assignee: Nordson Corp
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Filing: 1971-07-30
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Granted: 1973-05-22
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Expires: 1991-07-30
Abstract
Abstract A method and apparatus for spraying a coating material such as paint, in a flat fan pattern. In the gun a stream of paint under a relatively low pressure is caused to flow in an annular film. Streams of gas at a slightly higher pressure are directed against the paint film so that the gas is sheared into microbubbles which are entrained in the paint stream to form a froth. The froth flows through a chamber in which the bubbles disperse uniformly in the paint and is then discharged through a narrow slit nozzle effective to give it a fan shape. As the froth is released to atmospheric pressure, the microbubbles of air expand rapidly and rupture, causing the paint to disintegrate into finely atomized drops. The apparatus includes a cooperating orifice plate and collar which define a thin annular paint flow channel; and a plurality of air injection channels which intersect the paint flow channel. Air is introduced through these channels and is directed against the paint film. In the preferred gun, the nozzle includes a hemispherical endwise portion provided with an elongated discharge slot. A protuberance or ball is disposed within the nozzle and deflects the froth so that the froth passes through a relatively narrow passageway between the ball and nozzle. A modified gun includes a conventional airless flat fan orifice; and does not utilize an internal ball.
Inventors
- 👤 P Runstadler
- 👤 E Nord
- 👤 D Hastings
- 👤 S Rosen
- 👤 D Scarbrough
- 👤 F Wilhelm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 01:25
CPC Classifications
B; B05; B05B; B05B7/00; B05B7/02; B05B7/12; B05B7/1209; B05B7/1245; B05B1/00; B05B1/34; B05B1/02; B05B1/04; B05B1/042; B05B1/26; B05B1/262; B05B1/265; B05B7/24; B05B7/2489
Claims Analysis
Total Claims: 36
Claim 1
Independent Claim
149 words
A paint spray gun for spraying a flat fan spray, said gun having an air conduit and a paint conduit, froth forming means including means communicating with said paint conduit and defining a film-forming channel for said paint, said channel having opposed walls, means communicating with said air conduit and including an opening in one of said walls for injecting bubbles of air from said air conduit into the paint film formed in said film-forming channel to form a froth, a nozzle member having an orifice, a confined space intermediate said froth-forming means and said nozzle orifice through which froth flows with the entrained air bubbles remaining under pressure, whereby when froth is discharged through the nozzle orifice the air bubbles expand to break up the paint into a spray of fine particles, the nozzle orifice being configurated to cause the paint spray to form a flat fan pattern.
Claim 2
Dependent Claim
149 words
A paint spray gun for spraying a flat fan spray, said gun having an air conduit and a paint conduit, froth forming means including means communicating with said paint conduit and defining a film-forming channel for said paint, said channel having opposed walls, means communicating with said air conduit and including an opening in one of said walls for injecting bubbles of air from said air conduit into the paint film formed in said film-forming channel to form a froth, a nozzle member having an orifice, a confined space intermediate said froth-forming means and said nozzle orifice through which froth flows with the entrained air bubbles remaining under pressure, whereby when froth is discharged through the nozzle orifice the air bubbles expand to break up the paint into a spray of fine particles, the nozzle orifice being configurated to cause the paint spray to form a flat fan pattern.
Claim 3
Dependent Claim
28 words
The paint spray gun of claim 1 in which the nozzle has a dome end and in which the orifice is a generally elongated slot in said dome.
Claim 4
Dependent Claim
18 words
The paint spray gun of claim 2 further comprising a protuberance disposed within said nozzle behind said orifice.
Claim 5
Dependent Claim
17 words
The paint spray gun of claim 3 in which said protuberance is a section of a ball.
Claim 6
Dependent Claim
30 words
The paint spray gun of claim 1 in which said orifice includes a small opening with the adjacent wall of said nozzle being cut in an inwardly tapered elliptical configuration.
Claim 7
Dependent Claim
206 words
A paint spray gun for spraying a flat fan spray, said gun comprising a body portion, an air conduit through said body portion, a paint conduit through said body portion and terminating in a tip member having a paint discharge opening formed therein, an orifice plate, said orifice plate having one face disposed toward said tip member and having a projection extending outwardly from the opposite side thereof, a collar member having a central opening receiving said projection to define an annular film-forming channel, said orifice plate having a bore extending therethrough to place said film-forming channel in fluid communication with the paint discharge port of said tip, said collar member having an inwardly extending air injection channel in communication with said air conduit for injecting bubbles of air into a film of paint in said channel to produce a froth, a nozzle having a narrow elongated orifice therein and an internal passageway therethrough in fluid communication with said film-forming chamber, a protuberance disposed within said nozzle intermediate said orifice and said film-forming channel, whereby when the froth is discharged from the nozzle orifice the air bubbles expand to break up the paint into a spray of fine particles, said spray having a flat fan pattern.
Claim 8
Dependent Claim
206 words
A paint spray gun for spraying a flat fan spray, said gun comprising a body portion, an air conduit through said body portion, a paint conduit through said body portion and terminating in a tip member having a paint discharge opening formed therein, an orifice plate, said orifice plate having one face disposed toward said tip member and having a projection extending outwardly from the opposite side thereof, a collar member having a central opening receiving said projection to define an annular film-forming channel, said orifice plate having a bore extending therethrough to place said film-forming channel in fluid communication with the paint discharge port of said tip, said collar member having an inwardly extending air injection channel in communication with said air conduit for injecting bubbles of air into a film of paint in said channel to produce a froth, a nozzle having a narrow elongated orifice therein and an internal passageway therethrough in fluid communication with said film-forming chamber, a protuberance disposed within said nozzle intermediate said orifice and said film-forming channel, whereby when the froth is discharged from the nozzle orifice the air bubbles expand to break up the paint into a spray of fine particles, said spray having a flat fan pattern.
Claim 9
Dependent Claim
22 words
The paint spray gun of claim 6 in which said protuberance is mounted on a support arm extending forwardly from said projection.
Claim 10
Dependent Claim
44 words
The paint spray gun of claim 6 in which said nozzle terminates in a hemispherical dome wall adjacent said orifice and in which said protuberance includes a portion of a spherical surface concentric in at least one plane with the wall of said dome.
Claim 11
Dependent Claim
39 words
The paint spray gun of claim 8 in which said protuberance is carried on an arm extending forwardly from said projection and in which said protuberance includes a tapered wall section joining said hemispherical section and said support arm.
Claim 12
Dependent Claim
296 words
A paint spray gun for spraying a flat fan spray, said gun comprising a body portion, an air conduit through said portion, a paint conduit through said portion, said paint conduit terminating in a tip member having a paint discharge opening formed therein, an orifice plate, said orifice plate including a transverse base portion having a rear face in engagement with said tip portion, a cylindrical projection extending forwardly of said base portion, a collar member including a rearwardly extending flange embracing the periphery of said orifice base, and a transverse wall having a central opening receiving said projection to define an annular film-forming chamber, the orifice plate having a bore extending therethrough to place said film-forming channel in fluid communication with the paint discharge opening of said tip, said collar member including a forwardly projecting peripheral flange, the forward face of the transverse wall or the collar member having an inwardly projecting slot formed therein and communicating with said central opening, said slot also extending outwardly through said forwardly projecting flange, a nozzle member having a base in abutment with the forward face of said collar member and overlying said slot to define an air injection channel, means interconnecting the outer end of said slot with said air conduit, said nozzle member base being telescopically received within said forwardly extending flange, said nozzle member providing an internal passage and including a nozzle orifice, whereby when air is injected into said film of paint a froth is formed which flows outwardly through the space in said nozzle and when the froth is discharged from the nozzle orifice the air bubbles expand to break up the paint in a spray of fine particles, the nozzle orifice being configurated to spray paint to form a flat fan pattern.
Claim 13
Dependent Claim
296 words
A paint spray gun for spraying a flat fan spray, said gun comprising a body portion, an air conduit through said portion, a paint conduit through said portion, said paint conduit terminating in a tip member having a paint discharge opening formed therein, an orifice plate, said orifice plate including a transverse base portion having a rear face in engagement with said tip portion, a cylindrical projection extending forwardly of said base portion, a collar member including a rearwardly extending flange embracing the periphery of said orifice base, and a transverse wall having a central opening receiving said projection to define an annular film-forming chamber, the orifice plate having a bore extending therethrough to place said film-forming channel in fluid communication with the paint discharge opening of said tip, said collar member including a forwardly projecting peripheral flange, the forward face of the transverse wall or the collar member having an inwardly projecting slot formed therein and communicating with said central opening, said slot also extending outwardly through said forwardly projecting flange, a nozzle member having a base in abutment with the forward face of said collar member and overlying said slot to define an air injection channel, means interconnecting the outer end of said slot with said air conduit, said nozzle member base being telescopically received within said forwardly extending flange, said nozzle member providing an internal passage and including a nozzle orifice, whereby when air is injected into said film of paint a froth is formed which flows outwardly through the space in said nozzle and when the froth is discharged from the nozzle orifice the air bubbles expand to break up the paint in a spray of fine particles, the nozzle orifice being configurated to spray paint to form a flat fan pattern.
Claim 14
Dependent Claim
29 words
The paint spray gun of claim 10 in which said nozzle orifice includes a small aperture and the surrounding nozzle wall is pRovided with an inwardly tapered elliptically-shaped recess.
Claim 15
Dependent Claim
32 words
The paint spray gun of claim 10 in which said nozzle includes a hemispherical dome wall and in which said gun further includes a protuberance disposed behind the orifice in said nozzle.
Claim 16
Dependent Claim
25 words
The paint spray gun of claim 12 in which said protuberance includes a hemispherical portion concentric in at least one plane with said dome wall.
Claim 17
Dependent Claim
21 words
The paint spray of claim 13 in which said protuberance is carried on a support member extending forwardly from said projection.
Claim 18
Dependent Claim
24 words
The paint spray gun of claim 14 in which said collar member is provided with two diametral air injection slots in its forward face.
Claim 19
Dependent Claim
40 words
The paint spray gun of claim 10 further comprising a retaining nut surrounding said tip, orifice plate, collar, and base of said nozzle member, said retaining nut defining an air chamber interconnecting the air conduit and said air injection channel.
Claim 20
Dependent Claim
36 words
The paint spray gun of claim 16 in which said retaining nut includes a shoulder engaging said nozzle member base for holding said nozzle member, collar and orifice plate in stacked relationship against said tip member.
Claim 21
Independent Claim
108 words
A method of forming a flat fan paint spray, said method comprising the steps of injecting a plurality of microbubbles of air into a stream of paint to form a froth, the air and paint being intermixed as to have a mass ratio of air-to-paint of from 0.1 to 1.6, causing said froth to flow through a confined space toward a nozzle having an orifice therein effective to impart a fan-shaped pattern to a spray, and causing said froth to flow outwardly through said orifice whereupon the entrained bubbles expand and burst to break up said paint into a spray of fine particles having a flat fan pattern.
Claim 22
Independent Claim
108 words
A method of forming a flat fan paint spray, said method comprising the steps of injecting a plurality of microbubbles of air into a stream of paint to form a froth, the air and paint being intermixed as to have a mass ratio of air-to-paint of from 0.1 to 1.6, causing said froth to flow through a confined space toward a nozzle having an orifice therein effective to impart a fan-shaped pattern to a spray, and causing said froth to flow outwardly through said orifice whereupon the entrained bubbles expand and burst to break up said paint into a spray of fine particles having a flat fan pattern.
Claim 23
Dependent Claim
26 words
The method of claim 18 further comprising the step of causing said froth to flow transversely around a protuberance prior to its discharge from said orifice.
Claim 24
Independent Claim
110 words
A method of forming a flat paint spray, said method comprising the steps of forming a thin film of paint, causing said thin film to pass transversely of an air stream directed against said film to thereby inject a plurality of microbubbles of air into the thin film to form a froth, causing said froth to flow through a confined space toward a nozzle having an orifice therein effective to impart a fan-shaped pattern to a spray, and causing said froth to flow outwardly through said orifice whereupon the entrained bubbles expand and burst to break up said paint into a spray of fine particles having a flat fan pattern.
Claim 25
Independent Claim
110 words
A method of forming a flat paint spray, said method comprising the steps of forming a thin film of paint, causing said thin film to pass transversely of an air stream directed against said film to thereby inject a plurality of microbubbles of air into the thin film to form a froth, causing said froth to flow through a confined space toward a nozzle having an orifice therein effective to impart a fan-shaped pattern to a spray, and causing said froth to flow outwardly through said orifice whereupon the entrained bubbles expand and burst to break up said paint into a spray of fine particles having a flat fan pattern.
Claim 26
Dependent Claim
26 words
The method of claim 20 further comprising the step of causing said froth to flow transversely around a protuberance prior to its discharge from said orifice.
Claim 27
Dependent Claim
24 words
The method of claim 20 in which the paint is formed in an annular film prior to the injection of said microbubbles of air.
Claim 28
Dependent Claim
29 words
The method of claim 21 in which said film of paint is of an annular configuration and in which the air is injected from the outside of said annulus.
Claim 29
Dependent Claim
26 words
The method of claim 23 further comprising the step of causing said froth to flow transversely around a protuberance prior to its discharge from said orifice.
Claim 30
Dependent Claim
26 words
The method of claim 20 in which the air and paint are intermixed as to have a mass ratio of air-to-paint of from 0.1 to 1.6.
Claim 31
Dependent Claim
185 words
A paint spray gun for spraying a flat fan spray, said gun comprising: a body portion, an air conduit through said body portion, a paint conduit through said body portion and terminating in a paint discharge opening, an orifice plate, said orifice plate having one face disposed toward said paint discharge opening and having a projection extending outwardly from the opposite side thereof, a member having a central opening receiving said projection to define an annular film-forming channel, means providing fluid communication between said film-forming channel and the paint discharge opening, said inwardly extending aiR injection channel in communication with said air conduit for injecting bubbles of air into a film of paint in said channel to produce a froth, a nozzle having a narrow elongated orifice therein and an internal passageway therethrough in fluid communication with said film-forming chamber, a protuberance disposed within said nozzle intermediate said orifice and said film-forming channel, whereby when the froth is discharged from the nozzle orifice the air bubbles expand to break up the paint into a spray of fine particles, said spray having a flat fan pattern.
Claim 32
Dependent Claim
185 words
A paint spray gun for spraying a flat fan spray, said gun comprising: a body portion, an air conduit through said body portion, a paint conduit through said body portion and terminating in a paint discharge opening, an orifice plate, said orifice plate having one face disposed toward said paint discharge opening and having a projection extending outwardly from the opposite side thereof, a member having a central opening receiving said projection to define an annular film-forming channel, means providing fluid communication between said film-forming channel and the paint discharge opening, said inwardly extending aiR injection channel in communication with said air conduit for injecting bubbles of air into a film of paint in said channel to produce a froth, a nozzle having a narrow elongated orifice therein and an internal passageway therethrough in fluid communication with said film-forming chamber, a protuberance disposed within said nozzle intermediate said orifice and said film-forming channel, whereby when the froth is discharged from the nozzle orifice the air bubbles expand to break up the paint into a spray of fine particles, said spray having a flat fan pattern.
Claim 33
Dependent Claim
22 words
The paint spray gun of claim 26 in which said protuberance is mounted on a support arm extending forwardly from said projection.
Claim 34
Dependent Claim
44 words
The paint spray gun of claim 26 in which said nozzle terminates in a hemispherical dome wall adjacent said orifice and in which said protuberance includes a portion of a spherical surface concentric in at least one plane with the wall of said dome.
Claim 35
Dependent Claim
39 words
The paint spray gun of claim 28 in which said protuberance is carried on an arm extending forwardly from said projection and in which said protuberance includes a tapered wall section joining said hemispherical section and said support arm.
Claim 36
Dependent Claim
18 words
The spray gun of claim 28 in which the ends of said orifice are formed along radial lines.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |