Patent Description:
While examples described herein are in the context of applying paint to a surface, it is understood that the concepts are not limited to these particular applications. As used herein, paint includes substances composed of coloring matter, or pigments, suspended in a liquid medium as well as substances that are free of coloring matter or pigment. Paint may also include preparatory coatings, such as primers, and can be opaque, transparent, or semi-transparent. Some particular examples include, but are not limited to, latex paint, oil-based paint, stain, lacquers, varnishes, inks, etc..

Document <CIT>, which discloses the following, is known from the prior art: An improved reversible spray tip for use with airless paint spraying equipment to project a spray pattern, and mountable on a pressurized paint sprayer, comprising: a nozzle carrier, rotatable about an axis, and having a fluid passage and a spray nozzle in said fluid passage; a cam which co-rotates with said rotatable nozzle carrier, said cam having a position stop; and a counterstop disposed to engage said position stop when said nozzle carrier is rotated to a predetermined rotational position, so that rotation of said nozzle carrier from said given rotational position is bidirectionally resisted; wherein said position stop comprises a projecting detent for resisting rotation of said rotatable nozzle carrier.

Document <CIT>, which discloses the following, is also known from the prior art: A spray device, comprising: a rotatable, reversible spray tip, the spray tip having a handle for rotating the spray tip relative to a body of the spray device; a safety lock operatively connected to a) the body of spray device, b) a safety guard of the spray device, or c) a portion of a spray tip assembly of the spray device, the safety lock having a cover substantially conforming to the shape of the handle such that the cover is selectively engageable with the handle to prevent the handle from rotating out of a spraying position.

Document <CIT>, which discloses the following, is also known from the prior art: A spray nozzle comprising: a nozzle body, a nozzle entry orifice through which a material to be sprayed can enter, a nozzle bore through which a material to be sprayed can pass, a nozzle exit orifice through which a material to be sprayed can exit, a diamond bore liner in said bore for providing low wear, durable and long-lasting service in the nozzle.

Document <CIT>, which discloses the following, is also known from the prior art: In a liquid spray nozzle having flow capacity of not more than about <NUM> gallons of water per hour at <NUM> p. , comprising a body having a central void, comprising at least in part an approach passage, with a longitudinal axis and a fan spray outlet orifice at one end of said passage and with a side inlet at the other end of said passage and with an imperforate sidewall from said one end to said inlet, the area of said inlet being harmoniously related to the effective area of said outlet in respect to turbulent flow therebetween, the improvement comprising means for preventing the longitudinal inflow of liquid to the inlet end of said passage and defining a turbulence chamber in said void adjacent said inlet, and liquid inlet conducting means for introducing liquid into said chamber transversely of said axis with velocity and direction tending to induce turbulence in said chamber and avoid substantial bodily rotation of the fluid stream in said passage about said axis adjacent said orifice; both said means and said passage coacting to create a turbulent stream in said passage with substantially uniform mean velocity across the whole.

Document <CIT>, which discloses the following, is also known from the prior art: An airless spray gun nozzle, comprising: a cylindrical nozzle seat, wherein the end portion of the cylindrical nozzle seat forms a cross-shaped four passages, wherein two adjacent nozzles are respectively embedded with a circular nozzle and An elliptical nozzle such that the circular nozzle and the elliptical nozzle are at a <NUM>° cross-distribution; The nozzle holder is connected to the nozzle guard through the left and right snap rings; the left and right snap rings are composed of two semi-circular snap rings, one end of the two semi-circular snap rings is fastened by a buckle, and the other end is fastened by a snap ring cap; a semi-circular track groove is formed on the inner side of the curved portion of the shape snap ring; the semi-circular track groove can provide a guide for the rotation of the nozzle seat; The nozzle holder is provided with two bumps, and the two bumps correspond to the opening of the semi-circular rail groove and are inserted into the nozzle guard.

Document <CIT>, which discloses the following, is also known from the prior art: A method of manufacturing a spray nozzle comprising a nozzle tip and nozzle adapter, the nozzle tip being made from a hard, abrasive resistant material and the nozzle adapter being made from a material which is less hard, less abrasive resistant, and more easily machineable than the material from which the nozzle tip is made, the method comprising the steps of forming a generally semi-spherical dome shaped external peripheral surface on the tip, forming an axial approach passage in the tip terminating in a blind, generally semi-spherical end cavity coaxially aligned with the approach passage and the dome shaped peripheral surface, drilling and counterboring an axial passage through the adapter, the counterbored portion of the axial passage extending inwardly from a front face of the adapter; machining an annular groove in the frontface of the adapter so as to form an annular lip on said front face between the counterbored passage and the annular groove and an annular ring between the annular groove and the peripheral surface of said adapter; milling opposite sides of the front face of the adapter to the depth of the annular channel so as to create a pair of spaced arcuate ears on opposite sides of the front face of the adapter and a pair of arcuate lips spaced inwardly from the ears, inserting the tip into the counterbored axial passage of the adapter; swaging said lips over a portion of the tip so as to secure the tip within the bore, and brazing the tip to the adapter so as to form a liquid tight seal between the peripheral surface of the tip and the axial passage through the adapter.

A spray tip for a fluid applicator includes a stem configured to be inserted into the fluid applicator. The stem includes a stem pre-orifice portion and an insert receiving portion. The spray tip includes a pre-orifice insert having an inlet and an outlet. The pre-orifice insert is disposed within the insert receiving portion and disposed against a rearward shoulder of the stem.

This summary is not intended to identify key features or essential features of the claimed subject matter, is not intended to describe each disclosed embodiment or every implementation of the claimed subject matter, and is not intended to be used as an aid in determining the scope of the claimed subject matter. Many other novel advantages, features, and relationships will become apparent as this description proceeds. The figures and the description that follow more particularly exemplify illustrative embodiments.

In a fluid spraying system, a pump receives and pressurizes a fluid, delivers the pressurized fluid to an applicator, which, in turn, applies the pressurized fluid to a surface using a spray tip having a geometry selected to emit a desired spray pattern (e.g., a round pattern, a flat pattern, or a fan pattern, etc.). The fluid may comprise any fluid applied to surfaces, including, but not limited to, for example, paint, primer, lacquers, foams, textured materials, plural components, adhesive components, etc. For the sake of illustration, and not by limitation, the example of a paint spraying system will be described in detail.

<FIG> is a side view showing an example applicator <NUM>. Applicator <NUM> is used in a fluid spraying system to apply fluid to a surface (e.g., apply paint to a wall). The fluid enters through inlet <NUM>, and exits from outlet <NUM>, after passing through a fluid channel (not explicitly shown) within applicator <NUM>. Tip <NUM> is coupled to applicator <NUM> and has an outlet <NUM>. Tip <NUM> often is reversible or removable from applicator <NUM>. Tip <NUM> may have a pre-orifice configuration consisting of an internal geometry that provides a desired spray pattern (e.g., a fan that has minimal tailings or other beneficial fluid dynamics).

<FIG> is a side view showing an example spray tip <NUM>. Spray tip <NUM>, for example, could be used in applicator <NUM>. Spray tip <NUM> includes stem <NUM>, flag <NUM> and channel <NUM>. Stem <NUM> is typically cylindrical to allow rotation of spray tip <NUM> in an applicator (e.g., applicator <NUM> in <FIG>). Stem <NUM> can be formed of stainless steel, tungsten carbide or another suitable material. Flag <NUM> couples to stem <NUM> and allows a user to rotate and remove spray tip <NUM> from applicator <NUM>. Flag <NUM> can be press fit over stem or over molded onto stem, but other materials and methods of attachment are also envisioned. Channel <NUM> is disposed through stem <NUM> and allows fluid flow through spray tip <NUM>. Channel <NUM> and components disposed within channel <NUM> can be shaped to accommodate different fluids and spray patterns.

<FIG> is a sectional view of spray tip <NUM> along section A-A in <FIG>. As shown, stem <NUM> includes a channel <NUM> that allows fluid flow through stem <NUM>. Within channel <NUM> are pre-orifice inserts <NUM> and <NUM>. Fluid flows in through channel <NUM> into pre-orifice insert <NUM> and then into pre-orifice insert <NUM> before being expelled through orifice <NUM>. The internal structure of channel <NUM>, pre-orifice insert <NUM>, and pre-orifice insert <NUM> can greatly affect the spray pattern expelled from orifice <NUM>.

Spray tip <NUM> may be manufactured using current assembly processes for spray tips. Normally, pre-orifice inserts <NUM> and <NUM> are manufactured separately from stem <NUM>, and then inserted into channel <NUM>. Such machining often utilizes outside diameter (OD) grinding of pre-orifice inserts <NUM> and <NUM> (which generally comprise tungsten carbide) with tight press tolerances. The pre-orifice inserts <NUM> and <NUM> are then inserted into channel <NUM> of stem <NUM>. This process can create a large amount of scrap. Additionally, after the OD grinding process, pre-orifice inserts <NUM> and <NUM> might not press into stem <NUM> straight - in which case the assembly is considered a failure (e.g., the inserts do not align properly and can affect a desired spray pattern).

It is desired for a spray tip assembly process that does not require an OD grind, and where the parts assembly utilizes a slip fit, with a filler metal in a brazing process used to fill any gap. In one example, the filler metal used is a silver brazing filler metal. However, other suitable brazing filler metals, and other suitable bonding agents, are also envisioned.

<FIG> is a flow diagram showing an example assembly operation <NUM>. Assembly operation <NUM> is generally known, however, the internal geometries shown in <FIG> and <FIG>, respectively show low-pressure and high-pressure geometry configurations. Assembly operation <NUM> begins at block <NUM> where a stem is provided for example stem <NUM> shown in <FIG> and <FIG>.

Assembly operation <NUM> proceeds at block <NUM> where channel <NUM> is formed through stem <NUM>. Channel <NUM> can be formed in a variety of different ways as indicated by blocks <NUM>-<NUM>. As indicated by block <NUM>, channel <NUM> can be machined or drilled through stem <NUM>. For example, stem <NUM> is first formed as a cylinder and channel <NUM> is then bored into the cylindrical body of stem <NUM>. As indicated by block <NUM>, channel <NUM> can be casted or molded at the same time as stem <NUM>. For example, the cylindrical shape of stem <NUM> is formed by a casting process, however, a die is placed in the casting mold to create channel <NUM> in the stem forming casting process. As indicated by block <NUM>, channel <NUM> can be formed in other ways as well.

Assembly operation <NUM> proceeds at block <NUM> where pre-orifice inserts <NUM> are inserted within the stem <NUM>. Assembly operation <NUM> then proceeds to block <NUM> where the pre-orifice inserts <NUM> are secured within stem <NUM>. For example, the inserts are press fit against block <NUM> and as fluid flows through the inserts they are further forced against block <NUM> and cannot be pushed through entirely through channel <NUM>. In one example, pre-orifice inserts <NUM> are press fit into channel <NUM> and are held in by friction.

<FIG> is a flow diagram showing an example assembly operation <NUM>. Assembly operation <NUM> will be described with reference to <FIG>. Assembly operation <NUM> begins at block <NUM> where a stem is provided (e.g., stem <NUM>).

Assembly operation <NUM> proceeds at block <NUM> where a channel <NUM> is formed through the stem <NUM>. Channel <NUM> is shown formed in <FIG>. Channel <NUM> can be formed in a variety of different ways as indicated by blocks <NUM>-<NUM>. As indicated by block <NUM>, channel <NUM> can be machined or drilled through stem <NUM>. For example, a drill bit, end mill, or other tooling can be used to subtractively create the channel <NUM>. As indicated by block <NUM>, the channel <NUM> can be cast or molded into stem <NUM> during casting or molding of stem <NUM>. For example, a die is provided through the body of the mold to create channel <NUM>. As indicate by block <NUM>, channel <NUM> can be formed in stem <NUM> in other ways as well.

Assembly operation <NUM> proceeds at block <NUM> where internal geometry is formed in the stem. As shown in <FIG>, internal geometry can include channel <NUM>. As shown, portion <NUM>-<NUM> includes a cylindrical geometric portion, portion <NUM>-<NUM> is a frustoconical geometric portion and portion <NUM>-<NUM> is a cylindrical portion with a smaller diameter of than portion <NUM>-<NUM>. In this instance, portion <NUM>-<NUM> is the unmodified portion of channel <NUM> shown in <FIG>. Of course these are only examples and more complex geometry can also be formed in stem <NUM> such as step steps, spherical or other more complex shaping. The internal geometry formed in stem <NUM> can be formed in a variety of different ways as indicated by blocks <NUM>-<NUM>. As indicated by block <NUM>, the internal geometry can be machined or drilled in stem <NUM>. For example, utilizing the channel <NUM> as a guide, a tapered bit could drill into channel <NUM> all the way down to portion <NUM> - <NUM> and then to form portion <NUM>-<NUM> and <NUM>-<NUM>. (Drilling with this tapered bit all the way through stem <NUM> would create only one portion that would be similar to portion <NUM>-<NUM>. As indicated by block <NUM>, portion(s) <NUM> can be formed while casting or molding stem <NUM>. Portion(s) <NUM> can be formed in other ways as well, as indicated by block <NUM>.

Assembly operation <NUM> proceeds at block <NUM> where a pre-orifice retaining portion is formed (as shown in <FIG>) and the pre-orifice insert is inserted within stem <NUM> (as shown in <FIG>). For example, pre-orifice insert receiving portion <NUM> can be formed in similar ways as portions <NUM> (e.g., drilled, milled, molded, etc.). After the pre-orifice insert receiving portion <NUM> is formed, pre-orifice insert <NUM> can be inserted into pre-orifice insert receiving portion <NUM>. In some examples, pre-orifice insert <NUM> is press fit into pre-orifice insert receiving portion <NUM>. In other examples pre-orifice insert <NUM> snugly fits into pre-orifice insert receiving portion <NUM> such that a press is not needed. In other examples, pre-orifice insert <NUM> can loosely fit in pre-orifice insert receiving portion <NUM> to allow for more aligning options. In some examples, more than one pre-orifice insert <NUM> can be inserted into pre-orifice insert receiving portion <NUM>.

Assembly operation <NUM> proceeds at block <NUM> where the pre-orifice insert is secured within the stem. Pre-orifice insert <NUM> can be secured within the stem in a variety of different ways as indicated by block <NUM>-<NUM>. As indicated by block <NUM>, the pre-orifice insert <NUM> can be secured by brazing pre-orifice insert <NUM> into stem <NUM>. For example, a filler metal can be provided and brazed from the downstream direction of pre-orifice insert <NUM> and fill in a gap between pre-orifice insert <NUM> and stem <NUM>, securing pre-orifice insert <NUM>. As indicated by block <NUM>, a bonding agent can be used to secure pre-orifice insert <NUM> in stem <NUM>. For example, a glue, epoxy etc. can be used as a bonding agent to secure pre-orifice insert <NUM> into stem <NUM>. As indicated by block <NUM>, pre-orifice insert <NUM> can be secured in stem <NUM> by friction of (e.g., pre-orifice insert <NUM> tightly fits in pre-orifice insert receiving portion <NUM> such that it will not fall out under an applied fluid pressure flowing through channel <NUM>). Pre-orifice insert <NUM> can be secured in other ways as well, as indicated by block <NUM>. For example, a combination of one or more methods could be used. For instance, pre-orifice insert <NUM> may be secured using friction and a bonding agent.

<FIG> are sectional views showing example spray tip assembly configurations. As shown in <FIG>, a stem <NUM> includes a stem pre-orifice portion <NUM>, configured to guide fluid to pre-orifice insert <NUM>. Gap <NUM> between pre-orifice insert <NUM> and stem <NUM>, can allow for a fastening material to be applied to couple pre-orifice insert <NUM> to stem <NUM>. A fastening material may include filler or a bonding agent (e.g., a silver brazing filler metal, an epoxy or a different bonding agent). As shown, pre-orifice insert <NUM> is disposed rearwardly against rear shoulder <NUM> such that fluid does not flow around pre-orifice insert <NUM>. In some examples, the fastening material couples and/or bonds pre-orifice insert <NUM> to rear shoulder <NUM>.

As shown in <FIG>, stem <NUM> includes a stem pre-orifice portion <NUM>, configured to guide fluid to a pre-orifice insert <NUM>. Gap <NUM> between pre-orifice insert <NUM> and stem <NUM> can allow for a fastening material to be applied to couple pre-orifice insert <NUM> within stem <NUM>. A fastening material may include filler metal or a bonding agent (e.g., a silver brazing filler metal, an epoxy or some other bonding agent). As shown, pre-orifice insert <NUM> is disposed rearwardly of forward shoulder <NUM>. In some examples, the fastening material couples and/or bonds pre-orifice insert <NUM> to forward shoulder <NUM>.

As shown in <FIG>, stem <NUM> includes a stem pre-orifice portion <NUM>, configured to guide fluid to a pre-orifice insert <NUM>. Gap <NUM> between pre-orifice insert <NUM> and stem <NUM> can allow for a fastening material to be applied to couple pre-orifice insert <NUM> within stem <NUM>. A fastening material may include brazing material or a bonding agent (e.g., a silver brazing material or an epoxy bonding agent). As shown, pre-orifice insert <NUM> is disposed forwardly against forward shoulder <NUM> such that fluid under pressure does not force pre-orifice insert <NUM> out of stem <NUM>. In some examples, the fastening material couples and/or bonds pre-orifice insert <NUM> to forward shoulder <NUM>.

As shown in <FIG>, stem <NUM> comprises a stem pre-orifice portion <NUM>, configured to guide fluid to a pre-orifice insert <NUM>. Stem pre-orifice portion <NUM> may be machined or drilled as described above. Gap <NUM> between pre-orifice insert <NUM> and stem <NUM> can allow for a fastening material to be applied to couple pre-orifice insert <NUM> within stem <NUM>. A fastening material may include brazing material or a bonding agent (e.g., a silver brazing material or an epoxy bonding agent).

As shown in <FIG>, stem <NUM> includes a stem pre-orifice portion <NUM>, configured to guide fluid to a pre-orifice insert <NUM>. Stem pre-orifice portion <NUM> includes a cylinder <NUM>, a frustrum <NUM> and a cylinder <NUM>. In other examples, stem pre-orifice portion <NUM> can include other internal geometry in different configurations. For example, stem pre-orifice portion <NUM> can include the geometry of any available pre-orifice insert. For instance, stem pre-orifice portion <NUM> can remove the need for having two pre-orifice inserts to create internal concave geometry, such as a cavity or chamber that is wider than either the inlet or outlet. Some example geometries can include a plurality of stepped surfaces, widening surfaces, narrowing surfaces, spherical surfaces, cylindrical surfaces, etc. Gap <NUM> between pre-orifice insert <NUM> and stem <NUM> can allow for a fastening material to be applied to couple pre-orifice insert <NUM> within stem <NUM>. A fastening material may include brazing material or a bonding agent (e.g., a silver brazing material or an epoxy bonding agent). Gap <NUM> can be determined based on the properties of the brazing material or bonding agent. In one example, gap <NUM> includes a distance in the range <NUM> - <NUM> (<NUM> inches - <NUM> inches). In one example, gap <NUM> includes a distance in the range <NUM> - <NUM> (<NUM> inches - <NUM> inches).

As shown, pre-orifice insert <NUM> is disposed rearwardly against rear shoulder <NUM> such that fluid does not flow around pre-orifice insert <NUM> and/or in between pre-orifice insert <NUM> and stem <NUM>. In some examples, the fastening material couples and/or bonds pre-orifice insert <NUM> to rear shoulder <NUM>.

As shown in <FIG>, stem <NUM> includes a stem pre-orifice portion <NUM>, configured to guide fluid to a pre-orifice insert <NUM>. Gap <NUM> between pre-orifice insert <NUM> and stem <NUM> can allow for a fastening material <NUM> to be applied to couple pre-orifice insert <NUM> within stem <NUM>. Fastening material <NUM> may include brazing material or a bonding agent (e.g., a silver brazing material or an epoxy bonding agent).

Stem <NUM> includes a counter bore <NUM>. Counter bore <NUM>, as shown, includes a cylindrical shape. However, in other examples, counter bore <NUM> can include other geometries (e.g., frustums, steps, spheres, etc.). As shown, pre-orifice insert <NUM> is disposed rearwardly against rear shoulder <NUM> such that fluid does not flow around pre-orifice insert <NUM>. As shown, the fastening material <NUM> couples and/or bonds pre-orifice insert <NUM> to rear shoulder <NUM>.

Claim 1:
A spray tip (<NUM>) for a fluid applicator (<NUM>), the spray tip comprising:
a stem (<NUM>) configured to be inserted into the fluid applicator (<NUM>), the stem (<NUM>) comprising a stem pre-orifice portion (<NUM>) and an insert receiving portion (<NUM>);
a pre-orifice insert (<NUM>, <NUM>) comprising an inlet and an outlet; and wherein the pre-orifice insert (<NUM>) is mounted within the insert receiving portion (<NUM>) and disposed against a rearward shoulder (<NUM>, <NUM>) of the stem (<NUM>);
wherein the pre-orifice insert (<NUM>) is coupled to the pre-orifice receiving portion by a filler metal;
wherein the pre-orifice insert (<NUM>) is coupled to the rearward shoulder (<NUM>) by a filler metal;
wherein the stem pre-orifice portion comprises a frustum surface that widens in a downstream direction,
wherein the stem (<NUM>) includes a counter bore (<NUM>), wherein a fastening material (<NUM>) couples and/or bonds pre-orifice insert (<NUM>, <NUM>) to the rearward shoulder (<NUM>, <NUM>).