Patent Application
20190337007
Spray guns are known for the application of coatings to various substrates. It has been known to provide spray guns with air caps having air horns for the purpose of shaping a spray pattern. Such air caps are typically secured to the spray gun by means of a threaded ring that captures the air cap against the spray gun body. There is a need for improved connections between air caps and spray gun bodies.
Exemplary embodiments according to the present disclosure include, but are not limited to, the embodiments listed below, which may or may not be numbered for convenience. Several additional embodiments, not specifically enumerated in this section, are disclosed within the accompanying detailed description.
1. A spray gun air cap comprising
2. The spray gun air cap of Embodiment 1 comprising an endwall at the retention end, wherein the endwall comprises the retainer window.
3. The spray gun air cap of any of Embodiments 1 or 2 wherein the retainer window extends through the sidewall toward the forward end.
4. The spray gun air cap of any of Embodiments 1-3 wherein the air cap rotation guide extends through the sidewall.
5. The spray gun air cap of any of Embodiments 1-4 wherein the air cap rotation guide comprises a first end stop positioned at a first end of the arc.
6. The spray gun air cap of Embodiment 5 wherein the air cap rotation guide comprises a second end stop positioned at a second end of the arc.
7. The spray gun air cap of Embodiment 6 wherein the retainer window is positioned at an intermediate arcuate location between the first end stop and the second end stop.
8. The spray gun air cap of Embodiment 7 wherein the arc spans an angle about the spray axis in a range from 60 degrees to 120 degrees from the first end of the arc to the second end of the arc.
9. The spray gun air cap of Embodiment 8 wherein the retainer window is positioned at an angle in a range from 30 degrees to 60 degrees from one of the first end stop or the second end stop.
10. The spray gun air cap of any of Embodiments 8 or 9 wherein the arc spans an angle about the spray axis of 90 degrees from the first end of the arc to the second end of the arc
11. The spray gun air cap of any of Embodiments 8-10 wherein the retainer window is positioned at an angle of 45 degrees from one of the first end stop or the second end stop.
12. The spray gun air cap of any of Embodiments 1-11 wherein the reception feature comprises a hand grip adapted to facilitate manual rotation of the air cap about the spray axis.
13. The spray gun air cap of any of Embodiments 1-12 wherein the sidewall comprises a second air cap retention system opposite the spray axis from the first air cap retention system.
14. The spray gun air cap of any of Embodiments 1-12 comprising one of a retention rib or a retention channel positioned in the sidewall.
15. The spray gun air cap of Embodiment 14 wherein the retention rib or retention channel is positioned closer to the forward end than the air cap rotation guide.
16. A spray gun nozzle assembly comprising a nozzle body and a spray gun air cap according to any preceding Embodiment.
17. The spray gun nozzle assembly of Embodiment 16 wherein the nozzle body comprises a nozzle body retainer feature adapted to pass through the retainer window on the spray gun air cap.
18. The spray gun nozzle assembly Embodiment 17 wherein the nozzle body retainer feature is adapted to pass through the air cap rotation guide.
19. The spray gun nozzle assembly of any of Embodiments 17 or 18 wherein the nozzle body retainer feature cooperates with a rearward-oriented face of the retention wall on the spray gun air cap to retain the air cap against the nozzle body.
20. The spray gun nozzle assembly of any of Embodiments 16-19 wherein the spray gun air cap comprises a second air cap retention system comprising a second retention wall, and wherein the nozzle body comprises a second nozzle body retainer feature; wherein the second nozzle body retainer feature cooperates with the second retention wall on the spray gun air cap to retain the air cap against the nozzle body.
21. The spray gun nozzle assembly of any of Embodiments 16-20 wherein the nozzle body comprises a retention channel positioned to cooperate with the retention rib on the spray gun air cap.
22. The spray gun nozzle assembly of any of Embodiments 16-21 wherein the nozzle body comprises a primary air cap sealing feature positioned to cooperate with a sealing surface on the spray gun air cap.
23. The spray gun nozzle assembly of any of Embodiments 16-22 wherein the nozzle body is integral with a spray gun body.
24. The spray gun nozzle assembly of any of Embodiments 16-22 wherein the nozzle body is separable from a spray gun body.
25. A method of assembling an air cap to a nozzle body comprising aligning a retention end of a spray gun air cap with a nozzle body along a spray axis such that a retainer window on the spray gun air cap is rotationally aligned with a nozzle body retainer feature; and translating the spray gun air cap toward the nozzle body to cause the nozzle body retainer feature to pass into the retainer window.
26. The method of Embodiment 25 comprising, after causing the nozzle body retainer feature to pass into the retainer window, continuing to translate the spray gun air cap toward the nozzle body to cause a snapping of the spray gun air cap onto the nozzle body.
27. The method of Embodiment 25 wherein snapping of the spray gun air cap onto the nozzle body comprises seating a retention rib on one of the spray gun air cap or the nozzle body into a retention channel on the other of the spray gun air cap or the nozzle body.
28. The method of any of Embodiments 25-27 comprising, after causing the nozzle body retainer feature to pass into the retainer window, rotating the spray gun air cap about the spray axis with respect to the nozzle body to cause the nozzle body retainer feature to ride along an air cap rotation guide.
29. The method of Embodiment 28 wherein, while the nozzle body retainer feature resides in the air cap rotation guide, the nozzle body retainer feature bears against a retention wall to resist separation of the spray gun air cap from the nozzle body.
30. The method of any of Embodiments 25-29 comprising rotating the spray gun air cap in a first direction about the spray axis with respect to the nozzle body to cause the nozzle body retainer feature to ride along an air cap rotation guide until the nozzle body retainer feature contacts a first end stop.
31. The method of Embodiment 30 comprising rotating the spray gun air cap in a second direction opposite the first direction about the spray axis with respect to the nozzle body to cause the nozzle body retainer feature to ride along the air cap rotation guide until the nozzle body retainer feature contacts a second end stop.
32. The method of Embodiment 31 wherein the air cap rotation guide spans an arc about the spray axis from a first end of the arc to a second end of the arc, wherein the first end stop is located at the first end and the second end stop is located at the second end, the method comprising rotating the spray gun air cap throughout the arc to cause the nozzle body retainer feature to contact the first end stop and the second end stop.
33. The method of any of Embodiments 31 or 32 wherein the retainer window is positioned at an intermediate arcuate location between the first end stop and the second end stop, wherein the nozzle body retainer feature can pass transversely through the retainer window as the spray gun air cap is rotated between the first end stop and the second end stop.
34. The method of any of Embodiments 28-33 comprising
The words “preferred” and “preferably” refer to embodiments described herein that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.
As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a” or “the” component may include one or more of the components and equivalents thereof known to those skilled in the art. Further, the term “and/or” means one or all of the listed elements or a combination of any two or more of the listed elements.
It is noted that the terms “comprises” and variations thereof do not have a limiting meaning where these terms appear in the accompanying description. Moreover, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably herein.
Relative terms such as left, right, forward, rearward, top, bottom, side, upper, lower, horizontal, vertical, and the like may be used herein and, if so, are from the perspective observed in the particular figure. These terms are used only to simplify the description, however, and not to limit the scope of the invention in any way.
Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments” or “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.
The above summary is not intended to describe each embodiment or every implementation of the reservoirs and associated vent assemblies described herein. Rather, a more complete understanding of the invention will become apparent and appreciated by reference to the following Description of Illustrative Embodiments and claims in view of the accompanying figures of the drawing.
These and other aspects of the invention will be apparent from the detailed description below. In no event, however, should the above summaries be construed as limitations on the claimed subject matter, which subject matter is defined solely by the attached claims, as may be amended during prosecution.
Throughout the specification, reference is made to the appended drawings, where like reference numerals designate like elements, and wherein:
Referring to
The liquid spray gun nozzle assembly 100 comprises one end of a liquid spray gun coating liquid connector 104 (located at a coating liquid inlet portion 102), through which a coating liquid is supplied to the liquid spray gun 2 from an external liquid source 6′. As shown, for example, in
Within the liquid spray gun nozzle assembly 100 is a coating liquid flow path 110 through which the coating liquid flows from the liquid spray gun coating liquid connector 104 to a liquid nozzle 108 (see, e.g.,
The liquid spray nozzle assembly comprises an air cap 115 affixed to the spraying end thereof. The air cap 115 can direct pressurized air advantageously toward the stream of coating liquid, e.g., via one or more shaping air outlets 116 located in one or more air horns 117, as it is expelled from the liquid nozzle 108 to assist in atomization of the coating liquid and shaping of the coating liquid jet into the desired spray pattern for a given application. Within the air cap or proximate the air cap, the center air outlet 107 directs air around the liquid outlet 108 to draw the coating liquid from the liquid nozzle 108 and (if desired) also impinges upon the coating liquid to atomize it, creating a fine mist of droplets. Optionally, one or more auxiliary air outlets 118 may be provided in the air cap 115 to further assist in shaping the spray pattern. Portions of the air cap 115, the center air outlet 107, the liquid nozzle 108, the air horns 117, the auxiliary air outlets 118, and the shaping air outlets 116 may be configured as described in U.S. Pat. Pub. Nos. 2016/0052003 A1 (“Liquid Spray gun, spray gun platform, and spray head assembly”); 2013/0327850 A1 (“Nozzle tips and spray head assemblies for liquid spray guns”); 2014/0246519 A1 (“Spray head assembly with integrated air cap/nozzle for a liquid spray gun”); 2013/0092760 A1 (“Spray head assemblies for liquid spray guns”); 2015/0069142 A1 (“Spray gun barrel with inseparable nozzle”); 2016/0151797 A1 (“Air caps with face geometry inserts for liquid spray guns”); 2016/0175861 A1 (“Nozzle assemblies, systems and related methods”); and/or in WO2015/191323; and/or WO2016/033415, the disclosures of which are hereby incorporated by reference in their entireties. In the embodiments shown, the coating liquid is contained entirely within the liquid spray gun nozzle assembly 100, thus generally avoiding the need to clean the liquid spray gun body 3 after use.
The external liquid source 6′ may be a container that is directly affixed to the liquid spray gun nozzle assembly 100 (see, e.g.,
As shown, the nozzle assembly connection portion 200 facilitates the attachment of the paint spray gun nozzle assembly 100 to the paint spray gun body 3 by way of a locking ring 210 as described in U.S. provisional patent application No. 62/430,383 (3M Docket No. 77384US002), entitled “Spray Gun and Nozzle Assembly Attachment,” filed Dec. 6, 2016, the disclosure of which is herein incorporated by reference in its entirety. In other embodiments, the connection between the paint spray gun nozzle assembly 100 and the paint spray gun body 3 may be carried out by other means, such as, for example, a threaded collar, by one or more lever elements 130 as described, for example, in U.S. Pat. No. 8,590,809 B2 to Escoto, Jr. et al., by manually operable means for releasably mounting as described in U.S. Pat. No. 6,971,590 B2 to Blette et al., or by releasable mounts as described in U.S. patent publication number 2006/0065761 A1 to Joseph et al., the disclosures of which are herein incorporated by reference in their entirety. In other embodiments not shown herein, the paint spray gun nozzle assembly 100 is integral with (or at least not readily removable from) the spray gun body.
As shown in
The exemplary nozzle assembly connection portion 200 facilitates the attachment of the liquid spray gun nozzle assembly 100 to the liquid spray gun body 3 by way of a captured, rotatable locking ring 210, as seen in
Referring now to
In
As best seen in
In the embodiments shown in the drawings, the nozzle body retainer feature(s) 410 comprise protrusions from the outer wall 124 of the nozzle body 100′ (see, e.g.,
In some embodiments, the air cap rotation guide(s) 320 comprise first and second end stops 322, 324 to allow the user to position the air cap in preset rotational positions, as shown in
Assuming the above vertical and horizontal preset positions will be the most commonly chosen by the user, the user will want to assure secure retention of the air cap in those positions. Therefore, in the embodiments shown, the retainer window(s) 312 is located in an intermediate rotational position with respect to these preset positions. In particular, the retainer windows(s) 312 are located in a central rotational portion of the air cap rotation guide 320. For example, if the air horns 117 are positioned horizontally (for a vertical spray pattern) at a rotational position of 0 degrees, and the air horns 117 are positioned vertically (for a horizontal spray pattern) at a rotational position of 90 degrees, the retainer window(s) 312 may be positioned along the air cap rotation guide 320 such that the air cap 115 may be installed and/or removed at a rotational position of 45 degrees. Of course, this angle need not be precisely 45 degrees, but may be chosen to be any angle that permits secure retention at desired preset rotational position(s) while allowing installation/removal at another position. For example, the rotational position of the retainer window may be chosen in a range from 30 degrees to 60 degrees from either the first or second end stop. Because one or more retention grooves 420 and retention ribs 340 may be provided to allow further security against detachment (i.e., security beyond just a rearward-oriented face 410′ of nozzle body retainer feature 410 bearing against a retention wall 321), the position of the retainer window 312 may in some embodiments be chosen to correspond with the location of the first or second end stop (i.e., positioned at an angle of 0 degrees from an end stop).
The air cap 115 may be removed for cleaning and/or replaced, if desired, by aligning the retainer window(s) 312 with the nozzle body retainer feature(s) 410 and pulling along the spray axis 101 to separate the air cap 115 from the nozzle body 100′. In this manner, the air cap 115 is rotated to a position where a rearward-oriented face 410′ of the nozzle body retainer feature 410 will not bear against a retention wall 321, and can thus be detached axially along the spray axis 101. In one embodiment, the user is provided with different air caps 115 for a given nozzle body 100′ and may wish to swap them depending on the desired application. For example, one air cap may comprise a different air horn geometry and/or different shaping air outlets, or may not contain any air horns at all (such as where no pattern shaping is needed). The present disclosure allows for such swapping without the need for loose auxiliary parts (e.g., the typically-provided threaded ring) that might otherwise be lost or damaged.
In some embodiments, the air cap 115 and/or the nozzle body 100′ further or alternatively comprise one or more cooperating retention channels 420 and retention ribs 340. Such cooperating features may provide enhanced resistance against axial separation of the air cap 115 from the nozzle body 100′. An exemplary retention channel 420 may be seen in isolation in
In some embodiments, a cooperating pair of a retention channel 420 and a retention rib 340 can act to provide a positive snap-fit of the air cap 115 onto the nozzle body 100′. Such snapping is realized by way of deformation and relaxation of the air cap 115 as it is pressed into place onto the nozzle body 100′. In particular, in the configurations depicted, the retention rib 340 must deform outwardly to clear an outer wall of the nozzle body 100′ (in this case the primary air cap sealing feature 430), and after so clearing will relax to become seated within the retention channel 420. If this relaxation is rapid, a snapping effect can be achieved. The snapping effect may be an effect that is felt by the user, but may also be audible if desired.
In some embodiments, the air cap 115 and/or the nozzle body 100′ comprise a primary air cap sealing feature 430. In the embodiments shown, the primary air cap sealing feature 430 comprises a ring-shaped member on the nozzle body 100′. Upon assembly of the air cap 115, the primary air cap sealing feature 430 presses against an air cap sealing surface 119 (which, as shown in the illustrated embodiments, comprises an inner wall of the air cap 115) with sufficient force and continuity to create a seal against compressed air, such seal being sufficient to essentially prevent compressed air from escaping the air cap around its rear perimeter under normal operating conditions. In some embodiments, the primary air cap sealing feature 430 is comprised of the same material as the remainder of the nozzle body 100′ (or another relatively non-resilient material), and provides a seal by virtue of simple cooperation with the air cap sealing surface 119. For example, the air cap 115 may comprise a thin enough wall and/or a soft enough material as to slightly deform outwardly due to the force applied by the air cap sealing feature. In such cases, the fit between the air cap 115 and the nozzle body 100′ may be described as an interference fit.
In some embodiments, a secondary air cap sealing feature 440 is further provided (see, e.g.,
It is also envisioned that sealing materials (e.g., elastomers) and/or members (e.g., o-rings, gaskets, etc.) may be provided instead of or in addition to an interference fit as described above.
Optionally, interaction between the primary air cap sealing feature 430 and the air cap sealing surface 119 further provides a degree of resistance against rotation of the air cap 115 relative to the nozzle body 100′. Where so provided, such resistance should be sufficient to prevent the air cap 115 from rotating on its own (e.g., in response to vibration, movement of the spray gun in use, or minor impacts), but permit the air cap 115 to be selectively rotationally positioned by hand about the spray axis 101 such that the desired spray pattern can be obtained by the user. For example, the user may wish (even during spraying) to quickly rotate the air cap 115 to change the pattern from vertical to horizontal (or some angle therebetween) in order to facilitate holding the spray gun in differing orientations and/or spraying differently situated and/or shaped surfaces. In this way, the user may advantageously rapidly alter the orientation of the spray pattern without the need to first loosen any parts, without the use of tools, and without breaking or compromising the seal between the air cap 115 and the nozzle body 100′ in the process.
In some embodiments, the one or more reception features 310 may further act as gripping features to facilitate the user's rotation of the air cap 115 to the desired rotational position, and also to assist with installation and/or removal of the air cap 115 from the nozzle body 100′.
In some embodiments, the air cap 115 may be provided as a disposable part, if desired, thereby minimizing replacement cost. Furthermore, the air cap 115 can be constructed of a resilient material (such as an injection molded polymer) not only to reduce cost but also to provide the necessary resilience needed to perform the sealing and rotational resistance functions as described herein (i.e., permitting the air cap sealing surface 119 to deform slightly to seal against the air cap sealing feature 430 and/or a retention rib 340 to seat into a cooperating retention channel 420.
It should be understood that, while the air caps 115 depicted in the appended figures in combination with a spray gun having a removable nozzle body 100′, the advantages described in the preceding several paragraphs are not limited to use on the depicted spray gun(s), and are applicable to other types of spray guns. For example, it is envisioned that, in a typical spray gun comprising an integral, non-removable liquid channel, the threaded retaining ring could be eliminated and replaced with the air cap retention system described herein. Therefore, wherever it is stated that features related to air cap retention, sealing, positioning, etc. may be located on the nozzle body 100′, it should be understood that such features may alternatively be located on a spray gun body. Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2017/057668 | 12/5/2017 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62430393 | Dec 2016 | US |
