Lance base, lance, lance kit, method of manufacturing a base and retrofitting a lance

Abstract

The invention relates to a lance base body, a lance, a lance set, a method for producing a base body and for retrofitting a lance, the base body having at least one head region for accommodating a nozzle device, the head region having at least one inner wall portion, an outer wall portion and an intermediate wall portion arranged therebetween, the wall portions being formed annularly and integrally with the base body, and the front end of the intermediate wall portion being set back relative to the front end of the outer wall portion along an axis. By virtue of this particular design of the base body according to the invention, no additional sealing element is required for sealing between the atomizing gas region and the corner gas region, the intermediate wall portion of the base body according to the invention is also well protected against damage in the event of the nozzle being unscrewed and the lance head can be formed extremely compactly. The invention also relates to a lance, in particular a paint spray gun, a lance set, a method for producing a base body for a lance, in particular a paint spray gun, and a method for retrofitting a lance, in particular a paint spray gun.

Description

[0001] This invention is a divisional application of the parent application of Chinese patent application No. 201910703261.2, filed on July 31, 2019, entitled “Spray gun substrate, spray gun, spray gun kit, method for manufacturing substrate and modified spray gun”. Technical Field

[0002] This invention relates to a substrate for spray guns, particularly paint spray guns; spray guns, particularly paint spray guns; spray gun kits; a method for manufacturing a substrate for spray guns, particularly paint spray guns; and a method for modifying spray guns, particularly paint spray guns. Background Technology

[0003] According to existing technology, spray guns, especially paint spray guns, and particularly compressed gas atomizing paint spray guns, have a paint nozzle at their head, which screws into the gun body. The paint nozzle typically has a hollow cylindrical plug at its front end, through which the material to be sprayed exits during spray gun operation. However, the paint nozzle can be designed to be tapered in its front end region. The spray gun head typically has external threads, through which an air cap disposed and screwed onto the gun head. The air cap has a central opening with a diameter larger than the outer diameter of the paint nozzle plug or the outer diameter of the tapered front end of the paint nozzle. The central opening of the air cap and the plug or the front end of the paint nozzle together form an annular gap. The so-called atomizing gas exits through this annular gap, and in the nozzle arrangement described above, the atomizing gas creates a vacuum at the end face of the paint nozzle, thereby drawing the material to be sprayed out of the paint nozzle. The atomized gas is then directed onto the paint stream, whereby the paint stream is split into lines and bands. These lines and strips disintegrate into droplets due to their hydrodynamic instabilities, namely the interaction between the rapidly flowing compressed gas and the ambient gas, and due to gas dynamic disturbances. The droplets are blown away from the nozzle by the atomizing gas.

[0004] The air cap typically also has two corner structures, which are diametrically opposed and extend beyond the so-called annular gap and material outlet in the outflow direction. Two supply through-holes, i.e., corner structure gas delivery channels, extend from the rear side of the air cap to the corner structure gas through-holes in the corner structures. Typically, each corner structure has at least one corner structure gas through-hole; however, preferably, each corner structure has at least two corner structure gas through-holes from which the corner structure gas exits. The corner structure gas through-holes are typically oriented such that they point downstream of the annular gap towards the nozzle longitudinal axis in the exit direction, so that the so-called gas corner structure exiting the corner structure gas through-holes can influence the gas or paint stream that has already exited the annular gap or the paint mist that has at least partially formed. As a result, the paint stream, or also the jet stream (circular stream), which originally has a circular cross-section, is compressed together on its side facing the corner structure and extends in a direction perpendicular to it. This forms a so-called diffusion jet, which results in a higher topcoat speed. In addition to jet stream deformation, the corner structure gas is intended to further atomize the jet stream.

[0005] Typically, a gas channel is disposed within the spray gun body, i.e., the base of the spray gun. Gas from the channel described above is guided to a so-called annular gap for use as an atomizing gas, and gas from another channel described above is guided to a so-called corner structure gas opening for use as a corner structure gas. For this purpose, the gas channel converges into the end face of the spray gun head and is guided to the annular gap or corner structure gas through-hole via a gas disperser device. The gas disperser device typically includes a gas disperser ring that separates the atomizing gas region and the corner structure gas region from each other. Such nozzle devices or gas disperser devices are disclosed, for example, in DE 20 2010 012 449 U1 and Chinese Utility Model Documents ZL 2014 2 0431026.7 and ZL 2016 2 0911120.1.

[0006] The disadvantages of the aforementioned prior art, namely the gas disperser device with a gas disperser ring, are that the gas disperser ring is manufactured as a separate component by the spray gun manufacturer and must be installed by the spray gun manufacturer or user. The user must clean and replace this individual component. Furthermore, there is a risk of the gas disperser ring being lost, rendering the spray gun unusable until the user purchases a replacement. To achieve a simple seal between the atomized gas zone and the corner structure gas zone, the gas disperser ring is made of plastic. However, this makes the gas disperser ring susceptible to damage. Additionally, the gas disperser ring design according to the prior art is relatively complex.

[0007] US 2007 / 0262169 A1 cites Taiwan Utility Model Document TW 510253, which discloses a gun head structure in which the gun head has two annular grooves defined by a surrounding wall at the gun head. The described nozzle structure includes a sealing disc b, a connector c, a nozzle d, a spray head d, and a nut f.

[0008] The nozzle structure based on existing technology cited in US literature, and the device described in the US literature itself, includes numerous individual components with the aforementioned drawbacks. These components are constructed with relative finesse. In the event of damage to one component, there is a risk that the seal between the atomizing gas region and the corner structure gas region is no longer provided, negatively impacting the jet stream. Furthermore, the nozzle is relatively long due to the multiple stacked components. Summary of the Invention

[0009] Therefore, the object of the present invention is to provide a substrate for spray guns, especially paint spray guns, and a spray gun, especially paint spray gun, that is not easily damaged and is functionally safe.

[0010] Another object of the present invention is to provide a spray gun kit that can provide users with spray guns for different purposes.

[0011] Another object of the present invention is to provide an efficient method for manufacturing a substrate for spray guns, especially paint spray guns.

[0012] Another object of the present invention is to provide a method for modifying a spray gun, especially a paint spray gun, by means of which a spray gun having a first nozzle internal pressure, especially a paint spray gun, can be easily modified into a spray gun having a second nozzle internal pressure, especially a paint spray gun, and vice versa.

[0013] The first objective is to provide a base for a spray gun, particularly a paint spray gun, having at least one head region for accommodating a nozzle assembly. The head region has at least one inner wall portion, an outer wall portion, and an intermediate wall portion disposed therebetween. The wall portions are circumferentially and integrally formed with the base, and the front end portion of the intermediate wall portion is positioned axially rearward relative to the front end portion of the outer wall portion. Preferably, the front end portion of the intermediate wall portion is positioned axially 2 mm to 4 mm rearward relative to the front end portion of the outer wall portion.

[0014] A nozzle device that can be positioned in the head region may include, for example, a material nozzle, which is also commonly referred to as a paint nozzle, and is at least used to discharge the material to be sprayed; an air cap for discharging gas; and a gas nozzle ring for connecting the air cap to the substrate.

[0015] A separating wall or tab with a thickness of several millimeters can be particularly understood here as a wall portion extending substantially parallel to the central or longitudinal axis of the head region of the substrate, or substantially parallel to the central or longitudinal axis of a material nozzle that may be arranged in or on the substrate. Here, it can also be the central or longitudinal axis of the upper component of the substrate and / or the central or longitudinal axis of the receiving opening for accommodating a material quantity adjustment device. The wall portion preferably stands substantially vertically on a surface extending substantially perpendicular to one or more of the aforementioned central or longitudinal axes, such as the front of the head of the substrate. The terms "inner wall portion," "middle wall portion," and "outer wall portion" can be understood as meaning that, viewed from the front towards the nozzle, the inner wall portion is closer to the midpoint of the nozzle in the radial direction than the middle wall portion, and the middle wall portion is closer to the midpoint than the outer wall portion.

[0016] Here, the wall portion does not necessarily have to be circular and does not necessarily have to have a constant thickness. More precisely, the wall portion can also be designed as an ellipse, or another ellipse, or a triangle, such as a square or rectangle, and be thicker or thinner at at least one location than at at least one other location. However, the wall portion is preferably designed as circular and has a constant thickness.

[0017] The expression "integrally" in relation to the matrix means that the wall and the remaining matrix are made from a single workpiece, for example by means of casting, machining, 3D printing, or other methods. That is, the wall and the matrix do not need to be manufactured separately and then joined together. This reduces the number of individual components. Particularly preferably, the matrix is ​​first forged from a bent solid bar of material and then machined by means of a drilling machine, milling machine, or a combination thereof.

[0018] "Along the axis" here can be understood as along the central or longitudinal axis of the head region of the substrate, or the central or longitudinal axis of the material nozzle that may be arranged in or on the substrate. Here, the side of the substrate on which the spray direction or on which the material nozzle may be arranged is considered "front," and the opposite side or opposite direction is considered "rear," on which, for example, a material quantity adjustment device is arranged or may be arranged. The term "rear" relative to the front end of the outer wall section along the axis means that the front end of the outer wall section is further forward than the front end of the intermediate wall section. Here, the advantage is that the rearward-positioned intermediate wall section is better protected from damage than an intermediate wall section that extends beyond or is flush with the outer wall section. In the current situation, the intermediate wall section, especially its front end, i.e., the front edge or front edge region, is more critical to the reliability of the substrate or spray gun than the outer wall section, especially its front end, i.e., the front edge or front edge region.

[0019] Preferably, the front end of the intermediate wall portion is positioned 2 mm to 4 mm behind the front end of the outer wall portion along the axis. In this case, the substrate according to the invention provides sufficient space for a robust, functionally safe nozzle or its components, as described below.

[0020] The fact that the front end of the intermediate wall portion is positioned rearward relative to the front end of the outer wall portion along the axis means that the front edge of the intermediate wall portion is positioned rearward relative to the front end of the outer wall portion along the axis, at least locally. The front end of the outer wall portion does not necessarily precede the front edge of the intermediate wall portion over its entire extension. More precisely, the front edge of the outer wall portion can also be positioned rearward relative to the front edge of the intermediate wall portion, locally. This also means that the wall portion does not necessarily have a constant height over its entire extension. More precisely, the wall portion can have steps, shoulders, ramps, etc. However, preferably, the wall portion has a constant height over its extension and the front edge of the intermediate wall portion is positioned rearward relative to the front end of the outer wall portion along the axis over its entire extension.

[0021] Furthermore, the objective is also achieved by a spray gun, particularly a paint spray gun, which includes the substrate described above and below.

[0022] Furthermore, the objective is achieved by a spray gun, particularly a paint spray gun, comprising: at least one substrate, particularly the substrate described above and below; a nozzle having at least one material nozzle; an air cap; a first air guide region and a second air guide region, wherein the first air guide region guides gas for atomizing the material to be sprayed, and the second air guide region guides gas for influencing the jet stream, wherein the first and second air guide regions are separated from each other at least partially by a central wall of the substrate, a disc element integrally arranged at the material nozzle, at least one impact disc arranged at the material nozzle, particularly in a non-removable manner, and at least a portion of the air cap, wherein the central wall of the substrate is formed circumferentially. With the described design, the separation or sealing between the first and second air guide regions can be achieved solely by existing components, i.e., components that also fulfill functions different from separating the two regions. No additional sealing elements are required, thereby keeping the number of individual components low to overcome the aforementioned disadvantages or achieve the aforementioned advantages. The gas used for atomizing the material to be sprayed and the gas guided by the first air guide region are generally referred to as atomizing gas. The gas used to influence the jet stream and guided by the second guide zone is typically referred to as the corner structure gas. This zone is typically called the atomizing gas zone or the corner structure gas zone. The disc element can be considered part of the material nozzle, so that the impact disc actually arranged on the disc element can also be considered arranged on the material nozzle. The term "non-removable" arrangement of the impact disc at the material nozzle means that the impact disc cannot or should not be removed from the material nozzle without considerable effort and should not be attempted to remove it. For example, the impact disc can be pressed, glued, riveted, or welded to the material nozzle. A secure snap-fit ​​connection or a secure threaded connection can make the impact disc "non-removable."

[0023] Furthermore, the objective is achieved by a spray gun, particularly a paint spray gun, comprising: at least one substrate, particularly according to the above and below descriptions, the substrate having an outer wall portion and an intermediate wall portion; a nozzle having at least one material nozzle having a hollow section for guiding the material to be sprayed through and a material outlet; and a disc element disposed on the outer periphery of the hollow section, wherein the nozzle further comprises at least one impact disc disposed on the side of the disc element opposite to the material outlet and the impact disc having an inner periphery and an outer periphery, wherein the nozzle is disposed in or on the substrate such that a first gap, particularly a first annular gap, is formed between the outer wall portion and the at least one impact disc.

[0024] The above-described embodiments of the intermediate wall portion of the substrate according to the invention are correspondingly applicable to the intermediate wall portion of the spray gun according to the invention. The above description of the integral nature of the substrate and wall portion also applies similarly to the integral nature of the material nozzle and disc element, i.e., they are made from a single piece, for example by casting, machining, 3D printing, or other methods, thereby achieving the advantages already mentioned above. Neither the disc element nor the impact disc needs to be designed as a cylinder or have a circular bottom surface. More precisely, its width and length are only a few times its thickness. In other aspects, the disc element and the impact disc can have shapes on the lower side that differ from the upper side; the impact disc and the disc element can have different thicknesses at different locations; they can have constricted or expanded portions; they can have an elliptical or other oval-shaped upper or lower side; or they can be designed as angular plates. Furthermore, the impact disc and the disc element can be provided with openings or slots, or designed with other components or connected to other components. However, preferably, the disc element is designed as a disc or ring with a circular bottom surface, the disc or ring being concentrically arranged around the material nozzle. Therefore, material nozzle-disc element units can be easily manufactured by turning. The same applies to impact discs. Disc elements and impact discs can act as throttling rings, which, for example, limit the flow range of gas. The two components can alternatively or additionally act as gas deflection elements or gas guiding elements. In particular, the two components can be used to homogenize one or more gas flows. The two elements can be used to disperse one or more gas flows from one or more gas outlets over a larger area, so that the gas flow exists less as a point and more as a surface. Design examples of the components and their functions are described in detail below.

[0025] Another objective is achieved by a spray gun assembly comprising: at least one substrate, particularly the substrate described above and below; a first nozzle assembly having a first nozzle and a second nozzle assembly having a second nozzle, wherein the first nozzle assembly and / or the first nozzle is a low-pressure nozzle assembly and / or a low-pressure nozzle, and / or the second nozzle assembly and / or the second nozzle is a high-pressure nozzle assembly and / or a high-pressure nozzle. The first nozzle assembly or the first nozzle and the second nozzle assembly or the second nozzle can each be interchangeably mounted on the substrate. Depending on whether the user requires a low-pressure spray gun or a high-pressure nozzle for their coating work, the user can either arrange the low-pressure nozzle assembly or the low-pressure nozzle on or therein of the substrate, or arrange the high-pressure nozzle assembly or the high-pressure nozzle on or therein of the substrate, thereby obtaining a low-pressure spray gun or a high-pressure spray gun. The differences between a low-pressure nozzle assembly or the low-pressure nozzle and a high-pressure nozzle assembly or the high-pressure nozzle are described in detail below.

[0026] Another objective is achieved by a method for manufacturing a substrate for a spray gun, particularly a paint spray gun, especially the substrate described above and below, wherein the substrate has at least: a gas inlet channel, a first receiving opening for accommodating a gas quantity regulating device, a second receiving opening for accommodating a material quantity regulating device, at least one corner structure gas opening and an atomizing gas channel, and a head region having an inner wall portion, an outer wall portion and an intermediate wall portion disposed therebetween, wherein the substrate is manufactured integrally by means of 3D printing.

[0027] The advantages of 3D printing in manufacturing are particularly evident in the fact that the entire substrate can be manufactured in a single step. In contrast, manufacturing using forging or casting followed by, especially, rotary machining such as drilling and milling, requires components to be loaded into different tools or machines and then removed again after machining. Furthermore, 3D printing can be used to create shapes that are impossible or difficult to achieve using conventional manufacturing methods, such as undercuts. Moreover, virtually no material waste is generated. Substrates manufactured using 3D printing can be made, in particular, from plastics or metals.

[0028] The last objective is achieved by a method for converting a spray gun, particularly a paint spray gun, having a first nozzle internal pressure into a spray gun, particularly a paint spray gun, having a second nozzle internal pressure, wherein the first nozzle internal pressure is greater than the second nozzle internal pressure, wherein the method particularly includes, as a step, removing a high-pressure nozzle device from the base of the spray gun or removing a high-pressure nozzle device from the base of the spray gun, wherein the high-pressure nozzle device has at least one nozzle, the nozzle having a material nozzle, the material nozzle having a hollow section for guiding the material to be sprayed through and a material outlet, and wherein the method includes, as another step, arranging a low-pressure nozzle device in or on the base of the spray gun, wherein the low-pressure nozzle device has at least one nozzle, the nozzle having a material nozzle, the material nozzle having a hollow section for guiding the material to be sprayed through and a material outlet.

[0029] The objective is also achieved by a method for converting a spray gun, particularly a paint spray gun, having a first nozzle internal pressure into a spray gun, particularly a paint spray gun, having a second nozzle internal pressure, wherein the first nozzle internal pressure is less than the second nozzle internal pressure, wherein the method particularly includes, as a step, removing a low-pressure nozzle device from the base of the spray gun or removing a low-pressure nozzle device from the base of the spray gun, wherein the low-pressure nozzle device has at least one nozzle, the nozzle having a material nozzle, the material nozzle having a hollow section for guiding the material to be sprayed through and a material outlet, and wherein the method includes, as another step, arranging a high-pressure nozzle device in or on the base of the spray gun, wherein the high-pressure nozzle device has at least one nozzle, the nozzle having a material nozzle, the material nozzle having a hollow section for guiding the material to be sprayed through and a material outlet.

[0030] Spray guns, especially paint spray guns, operate using different pressure methods. Conventional spray guns operate with relatively high jet pressures of several bar. So-called HVLP (High-Volume Low-Pressure, High-Flow) guns have a maximum nozzle internal pressure of 10 psi or 0.7 bar, thus achieving a transfer rate well over 65%. Compliant (Low-Volume Low-Flow) spray guns, on the other hand, have a nozzle internal pressure of approximately 10 psi or 0.7 bar, yet also achieve a transfer rate above 65%.

[0031] According to existing technology, the HVLP spray gun differs from the Compliant spray gun in the following aspects: an additional throttling tube is inserted into the gas channel manifold in the head of the HVLP spray gun's base. This requires additional manufacturing steps, and the spray gun or base used to construct the HVLP spray gun cannot or is difficult to modify into a Compliant spray gun or Compliant spray gun base because the throttling tube must be securely inserted into the gas channel manifold, for example, by compression, to prevent accidental loosening.

[0032] A first method according to the invention for converting a spray gun, particularly a paint spray gun, having a first nozzle internal pressure into a spray gun, particularly a paint spray gun, having a second nozzle internal pressure, wherein the first nozzle internal pressure is greater than the second nozzle internal pressure, has the advantage that the spray gun body can remain unchanged when, for example, a Compliant spray gun needs to be converted into an HVLP spray gun. The spray gun can be easily converted into a spray gun with a lower nozzle internal pressure by changing the nozzle. It is possible to forgo manufacturing a separate throttling tube and introducing it into the spray gun body.

[0033] The second method according to the invention for converting a spray gun, particularly a paint spray gun, with a first nozzle internal pressure into a spray gun with a second nozzle internal pressure, wherein the first nozzle internal pressure is less than the second nozzle internal pressure, also has the advantage that the spray gun base can remain unchanged when, for example, an HVLP spray gun needs to be converted into a Compliant spray gun. The spray gun can be easily converted into a spray gun with a higher nozzle internal pressure by changing the nozzle. The difficult removal of the throttling tube inserted into the spray gun base can be avoided.

[0034] Another advantage of these two methods according to the invention for modifying spray guns, especially paint spray guns, is that they can also be easily modified after the spray gun has been delivered to the user.

[0035] The nozzle internal pressure of a spray gun should be understood as the pressure residing in the air cap of the spray gun. Here, the atomizing gas region is typically separated from the corner structure gas region, and the pressure in the atomizing gas region can differ from that in the corner structure gas region. However, the pressure in the atomizing gas region and the corner structure gas region can also be the same. The nozzle internal pressure can be measured, for example, by means of a so-called test air cap. Here, the test air cap is a special air cap arranged on the spray gun instead of a regular air cap. The test air cap typically has two fluid pressure stages, one of which is connected to the atomizing gas region via a through-hole in the test air cap, and the other is connected to the corner structure gas region via another through-hole in the test air cap.

[0036] The terms "low-pressure nozzle device" and "high-pressure nozzle device" do not imply that the corresponding nozzle devices are only used in typical low-pressure or high-pressure nozzles, or that the spray gun is transformed into a typical low-pressure, especially HVLP, spray gun or a typical high-pressure spray gun by using the corresponding nozzle devices. More precisely, it can only be understood that when equipped with a high-pressure nozzle device, the spray gun has a higher nozzle internal pressure than when equipped with a low-pressure nozzle device. Preferably, the spray gun equipped with a low-pressure nozzle device or the substrate equipped with a low-pressure nozzle device meets the standards for an HVLP spray gun, and the spray gun equipped with a high-pressure nozzle device or the substrate equipped with a high-pressure nozzle device meets the standards for a Compliant spray gun.

[0037] In addition to the nozzle, the nozzle assembly can also have an air cap and a gas nozzle ring. The nozzle includes at least one material nozzle with additional components that can be disposed thereon. All these components can be configured differently in a low-pressure nozzle assembly than in a high-pressure nozzle assembly; however, the difference can be limited to one or some of the components, while the other components in the low-pressure and high-pressure nozzle assemblies are the same. Preferably, the difference lies in the material nozzle, the components disposed thereon, or the air cap. The difference in the nozzle, the material nozzle, or the components disposed thereon can particularly be that the nozzle of the low-pressure nozzle assembly has an additional impact disc compared to the nozzle of the high-pressure nozzle assembly, and the first impact disc of the nozzle of the low-pressure nozzle assembly has a smaller outer perimeter than the first impact disc of the nozzle of the high-pressure nozzle assembly. Here, the additional impact disc can act as an additional throttling ring, limiting the flow range of the gas. However, alternatively or additionally, the additional impact disc can also perform the aforementioned functions of the first impact disc, such as gas guiding, gas deflection, homogenization, and / or gas dispersion. Furthermore, the disc elements of the nozzles in both low-pressure and high-pressure nozzle devices can have through-holes for gas, particularly through-holes. However, these through-holes can be constructed differently or exist in different numbers compared to those in low-pressure nozzle devices. The same applies to impact discs. A preferred difference in the air cap is that the central opening of the air cap in the low-pressure nozzle device has a larger diameter than that in the high-pressure nozzle device. Consequently, while the outer diameter of the front end of the material nozzle remains substantially the same, the annular gap formed by the outer surface of the front region of the material nozzle and the wall defining the central opening in the air cap is larger in the low-pressure nozzle device than in the high-pressure nozzle device, and the atomized gas exits from this annular gap.

[0038] Preferably, the inner wall and the intermediate wall define a first gas dispersion chamber, and the intermediate wall and the outer wall define a second gas dispersion chamber. This means that they preferably define such gas dispersion chambers with other walls or surfaces of the substrate or other components. The gas dispersion chamber is preferably not closed, but has an inlet, an outlet, and / or a through-hole. Preferably, the gas dispersion chamber is designed to be generally annular; however, other shapes are possible where advantageous. Preferably, the chamber is circumferential, i.e., extending in 360°; however, the chamber can also be defined in a smaller area. The purpose of the gas dispersion chamber is to disperse the gas flowing into the gas dispersion chamber from at least one opening over a larger area, preferably in 360°. The gas dispersion chamber between the inner wall and the intermediate wall can be referred to as the "inner gas dispersion chamber," and the gas dispersion chamber between the intermediate wall and the outer wall can be referred to as the "outer gas dispersion chamber." The inner gas dispersion chamber can be a gas dispersion chamber for atomizing gases, and the outer gas dispersion chamber can be a gas dispersion chamber for angularly structured gases.

[0039] A first front surface is preferably arranged between the inner wall portion and the intermediate wall portion, and a second front surface is arranged between the intermediate wall portion and the outer wall portion. The first front surface has at least a first distance along its axis from the front end of the outer wall portion in a localized manner, and the second front surface has at least a second distance along its axis from the front end of the outer wall portion in a localized manner. The first distance is greater than the second distance. The axis mentioned here refers to the central or longitudinal axis of the head region of the substrate, or the central or longitudinal axis of a material nozzle that can be arranged on or within the substrate. Here, the term "front surface" should be interpreted as the "forward" surface as defined above, specifically pointing towards the injection direction. Therefore, the front surface is substantially perpendicular to the aforementioned central or longitudinal axis and perpendicular to the wall portions, and the front surfaces are arranged between these wall portions. The front surface can form a base surface of the aforementioned gas dispersion cavity and is preferably a surface of the substrate. The first front surface is at least locally farther from the front end of the outer wall portion than the second front surface along the mentioned axis. However, the spacing does not need to be constant over the entire extension of the front surface. More precisely, the front surface can also have inclined portions, steps, depths, shoulders, etc.

[0040] Preferably, the first spacing, i.e., the distance from the front end of the outer wall portion along the axial direction between the inner wall portion and the intermediate wall portion, is 9 mm to 11 mm, and the second spacing, i.e., the distance from the front end of the outer wall portion along the axial direction between the intermediate wall portion and the outer wall portion, is 4 mm to 6 mm. Due to the different spacings, the inner gas dispersion cavity can have a greater depth than the outer gas dispersion cavity, and thus a larger volume despite a smaller base surface. If the gas dispersion cavities are considered as closed chambers, defined by the base surface, two adjacent walls, and a virtual covering surface, the volume of the inner gas dispersion cavity is particularly preferably 1000 mm². 3 and 1500mm 3 The volume of the external gas dispersion chamber is 400 mm. 3 and 900mm 3 Between them, the virtual covering surface is arranged parallel to the bottom surface on the lower of the two wall sections.

[0041] Preferably, at least the first front surface and / or the second front surface have grooves at least partially; particularly preferably, the second front surface has a groove at least partially, the groove having a bottom surface, wherein the bottom surface of the groove has a third distance from the front end of the outer wall portion along the axis, particularly the central or longitudinal axis of the head region of the substrate or the central or longitudinal axis of the material nozzle that may be arranged on or in the substrate, and wherein the third distance is less than the first distance from the front end of the outer wall portion of the first front surface. The bottom surface of the groove is therefore located along the axis between the first and second front surfaces. The aforementioned third distance consists of the distance between the second front surface and the front end of the outer wall portion plus the distance between the bottom surface of the groove and the second front surface, i.e., the depth of the groove.

[0042] The width of the groove in the first or second front surface preferably corresponds approximately to the width of the first or second front surface. The groove in the first front surface is particularly preferably approximately the same width as the first front surface, and the groove in the second front surface is particularly preferably approximately the same width as the second front surface. The width of the groove or front surface can be understood herein as the radial extension along the head region of the substrate, or as the radial spacing between the intermediate wall portion and the outer wall portion, or between the inner wall portion and the intermediate wall portion.

[0043] Particularly preferably, the groove extends circumferentially over 25% to 75%, particularly 45% to 55%, of the circumference of the first or second front surface. The first front surface preferably has at least one internal gas outlet, particularly two internal gas outlets, and the second front surface has at least one external gas outlet, particularly two external gas outlets. This, and particularly by extending over 25% to 75%, particularly 45% to 55%, of the circumference of the respective front surface, allows the gas flowing from at least one gas outlet to be better dispersed around the circumference of the gas dispersion chamber. If the respective front surface extends in 360°, then the groove preferably extends in 90° to 270°, particularly 162° to 198°. The terms "internal" and "external" gas outlets are used only to distinguish between gas outlets. Preferably, at least one "internal" gas outlet is located further in the radial direction than at least one "external" gas outlet, i.e., closer to the center or longitudinal axis of the head region of the substrate; however, the gas outlets can also have the same distance from the center or longitudinal axis of the head region of the substrate.

[0044] Particularly preferably, the first front side has two internal gas outlets and the second front side has two external gas outlets, wherein the external gas outlets are located within a groove in the second front side, and wherein the groove extends over approximately 50% of the circumference of the second front side.

[0045] At least one internal gas outlet on the first front extends at least locally over at least 85% of the width of the first front, and at least one external gas outlet on the second front extends at least locally over at least 85% of the width of the second front.

[0046] Particularly preferably, as mentioned above, there are two gas outlets in both the first and second front surfaces. The gas outlets are, in particular, through-holes, wherein it is advantageous that the diameter of the through-hole is as large as possible to achieve the largest possible gas volume. The space of the through-hole is constrained by the wall, therefore the through-hole, or gas outlet in general, should extend as wide as possible across the width of the front surface.

[0047] Preferably, the substrate has at least two atomizing gas channels extending from a first front surface into a circular diffuser jet gas dispersion cavity, and / or the substrate has at least two corner-structured gas channels extending from a second front surface into a circular diffuser jet gas dispersion cavity, wherein the atomizing gas channels are spaced apart from each other in the region of the first front surface and at least partially intersect in the region of the circular diffuser jet gas dispersion cavity, and / or wherein the corner-structured gas channels are spaced apart from each other in the region of the second front surface and at least partially intersect in the region of the circular diffuser jet gas dispersion cavity. In other words, the first front surface has two spaced-apart atomizing gas channel inlets and the second front surface has two spaced-apart corner-structured gas channel inlets. The circular diffuser jet gas dispersion cavity has only one atomizing gas channel inlet and one corner-structured gas channel inlet. The outer contour of the inlets can correspondingly have an "8"-shaped outer contour. Thus, the total cross-section of the two gas channels expands from the circular diffuser jet gas dispersion cavity to the front surface.

[0048] In a preferred embodiment of the substrate according to the invention, the front end of the inner wall portion is positioned rearward relative to the front end of the intermediate wall portion along the axis, particularly along the central or longitudinal axis of the head region of the substrate, or along the central or longitudinal axis of a material nozzle that may be disposed on or within the substrate. Particularly preferably, the front end of the inner wall portion is positioned 0.4 mm to 0.6 mm rearward relative to the front end of the intermediate wall portion along the axis.

[0049] The fact that the front end of the inner wall portion is positioned rearward relative to the front end of the intermediate wall portion along the axis means that the front edge of the inner wall portion is positioned rearward relative to the front edge of the intermediate wall portion along the axis, at least locally. The front edge of the intermediate wall portion does not necessarily precede the front edge of the inner wall portion over its entire extension. More precisely, the front edge of the intermediate wall portion is also partially behind the front edge of the inner wall portion. This also means that the wall portion does not necessarily have a constant height over its entire extension. More precisely, the wall portion can have steps, shoulders, ramps, etc. However, preferably, the wall portion has a constant height over its extension, and the front edge of the inner wall portion is positioned rearward relative to the front end of the intermediate wall portion along the axis over its entire extension.

[0050] Particularly preferably, the walls (i.e., the inner wall, the intermediate wall, and the outer wall) are each designed to be circular and arranged concentrically. This allows for simpler manufacturing of the shape, as it can be achieved relatively easily and quickly by turning or by using a rotationally symmetrical tool. Preferably, the shape can be manufactured in a single step when the tool profile corresponds to the profile of the head region of the front of the base, or is a negative mold of the profile. The nozzle or nozzle assembly that can be arranged on or in the head region can also therefore be designed to be at least partially rotationally symmetrical.

[0051] Preferably, the inner wall portion has an outer diameter of 13 mm to 15 mm, the middle wall portion has an outer diameter of 22 mm to 24 mm, and the outer wall portion has an outer diameter of 33 mm to 35 mm.

[0052] The inner wall portion has an inner diameter of 11 mm to 13 mm, the middle wall portion has an inner diameter of 20 mm to 22 mm, and the outer wall portion has an inner diameter of 31 mm to 33 mm.

[0053] Preferably, the inner wall portion has internal threads at least partially, and the outer wall portion has external threads at least partially. For example, a nozzle, especially a material nozzle, can be screwed into the internal threads of the inner wall portion along with other components disposed thereon. For example, a gas nozzle ring can be screwed onto the external threads of the outer wall portion. The threads can be, for example, metric threads, trapezoidal threads, or other threads. The internal threads of the inner wall portion should ensure a tight fit of the nozzle in the base and, if possible, ensure a seal between the areas guiding the material and the gas. The external threads of the outer wall portion should primarily enable quick installation and removal of the gas nozzle ring from the base, but should also ensure a seal between the gas guiding area and the environment. Preferably, the internal threads of the inner wall portion are pointed threads, and the external threads of the outer wall portion are high-speed threads, particularly trapezoidal threads.

[0054] Preferably, the nozzle of the spray gun according to the invention is disposed on or therein in the substrate, such that a second gap, particularly a second annular gap, is formed between the interior and at least one impact disc. The impact disc forming the second gap with the inner wall of the substrate can be a different impact disc than the one forming the first gap with the outer wall of the substrate as described above. The two impact discs can be integrally connected to each other. The two impact discs can also be considered as a single impact disc with different sections. However, the first gap and the second gap can also be formed by the same impact disc.

[0055] At least one impact disc of the spray gun according to the invention preferably has at least one sealing surface that seals against a mating sealing surface of the intermediate wall portion of the substrate, particularly against the front end of the intermediate wall portion of the substrate. This arrangement is particularly helpful for sealing, i.e., isolation between the first and second air guiding regions, especially between the region guiding atomized gas and the region guiding angular structure gas. Therefore, the wall portion and the impact disc, which primarily fulfill the above functions, also contribute to the sealing of the area, thereby eliminating the need for a separate sealing mechanism or sealing element.

[0056] Preferably, at least one impact disc of the spray gun according to the invention is formed by a first segment and a second segment, the first segment and the second segment forming a step with each other, wherein the outer diameter of the step substantially corresponds to the inner diameter of the intermediate wall portion of the substrate. The outer diameter of the step thus rests against the inner side of the intermediate wall portion, which can contribute to the sealing described above. Furthermore, no dead zone is formed between the impact disc and the intermediate wall portion, which could negatively affect the gas flow. The first and second segments of the impact disc can also be considered as two distinct impact discs that can be integrally connected to each other.

[0057] Preferably, within the scope of the method according to the invention for converting a spray gun, particularly a paint spray gun, having a first nozzle internal pressure into a spray gun, particularly a paint spray gun, having a second nozzle internal pressure, the high-pressure nozzle device is removed from or from the spray gun body, wherein the first nozzle internal pressure is greater than the second nozzle internal pressure, the nozzle of the high-pressure nozzle device further having a disc element arranged on the outer periphery of the hollow section and at least one first impact disc, wherein the first impact disc is disposed on the side of the disc element away from the material outlet and has an inner periphery and an outer periphery, and the nozzle of the low-pressure nozzle device (arranged on or in the spray gun body within the scope of the method according to the invention) also preferably has a disc element arranged on the outer periphery of the hollow section and at least one first impact disc, wherein the first impact disc is disposed on the side of the disc element away from the material outlet and has an inner periphery and an outer periphery, and has a second impact disc arranged on the side of the first impact disc away from the material outlet, wherein the outer periphery of the first impact disc of the low-pressure nozzle device nozzle is smaller than the outer periphery of the first impact disc of the high-pressure nozzle device nozzle.

[0058] The method according to the invention preferably includes, as a step, removing a high-pressure air cap arranged on the substrate via a gas nozzle ring, wherein the high-pressure air cap has at least one central opening (77) having a first diameter, and includes, as another step, arranging a low-pressure air cap arranged on the substrate via the gas nozzle ring, wherein the low-pressure air cap has at least one central opening having a second diameter, and wherein the second diameter is larger than the first diameter of the high-pressure air cap. Because the central opening of the air cap in the low-pressure nozzle device has a larger diameter than that in the high-pressure gas nozzle device, while the outer diameter of the front end of the material nozzle remains substantially the same, the annular gap between the material nozzle and the air cap is larger in the low-pressure nozzle device than in the high-pressure nozzle device, wherein the atomized gas exits from the annular gap. Therefore, the pressure of the air cap in the low-pressure nozzle device is lower than that in the high-pressure nozzle device, and the volumetric flow of the outflowing gas is larger.

[0059] Preferably, within the scope of the method according to the invention for converting a spray gun, particularly a paint spray gun, having a first nozzle internal pressure into a spray gun, particularly a paint spray gun, having a second nozzle internal pressure, a low-pressure nozzle device is removed from or from the spray gun body, wherein the first nozzle internal pressure is less than the second nozzle internal pressure, the nozzle of the low-pressure nozzle device further having a disc element arranged on the outer periphery of the hollow section and at least one first impact disc, wherein the first impact disc is arranged on the side of the disc element away from the material outlet and has an inner periphery and an outer periphery, and a second impact disc arranged on the side of the first impact disc away from the material outlet, and the nozzle of the high-pressure nozzle device (arranged on or in the spray gun body within the scope of the method according to the invention) also preferably has a disc element arranged on the outer periphery of the hollow section and at least one first impact disc, wherein the first impact disc is arranged on the side of the disc element away from the material outlet and has an inner periphery and an outer periphery, wherein the outer periphery of the first impact disc of the high-pressure nozzle device nozzle is larger than the outer periphery of the first impact disc of the low-pressure nozzle device nozzle.

[0060] The method according to the invention preferably includes removing a low-pressure air cap disposed on the substrate via a gas nozzle ring as a step, wherein the low-pressure air cap has at least one central opening having a first diameter, and includes arranging a high-pressure air cap disposed on the substrate via a gas nozzle ring as another step, wherein the high-pressure air cap has at least one central opening having a second diameter, and wherein the second diameter is smaller than the first diameter of the low-pressure air cap.

[0061] The method according to the invention for modifying spray guns, especially paint spray guns, can also be regarded as a method for modifying the substrate of spray guns, especially paint spray guns, and in particular as a method for modifying the substrate according to the invention described above and below.

[0062] The method according to the invention for manufacturing a substrate, and the method according to the invention for modifying a spray gun, can, as an additional step, include: delivering the substrate or spray gun to the customer and / or using the substrate or spray gun.

[0063] Embodiments for use with the substrate according to the invention, especially with the spray gun according to the invention, with the method for manufacturing the substrate according to the invention, and with the method for modifying the spray gun according to the invention, especially with the embodiments for components, are fully applicable; that is, embodiments for use with the substrate according to the invention are also applicable to the spray gun according to the invention or the method according to the invention, etc.

[0064] The spray guns according to the invention, especially paint spray guns, can be used not only to spray paints but also to spray adhesives or varnishes, particularly solvent-based or water-based primers and varnishes, and similarly to spray liquids used in the food industry, wood preservatives, or other liquids. The spray guns according to the invention can be handheld or automatic or robotic. Handheld spray guns are primarily used by artisans, especially painters, carpenters, and painters. Automatic and robotic guns are typically used in conjunction with painting robots or painting machines for industrial applications. Of course, it is entirely possible to integrate handheld spray guns into painting robots or painting machines as well.

[0065] The substrate according to the invention, the spray gun according to the invention, and the method according to the invention can be used for all types of spray guns, but are particularly suitable for spray guns for gas atomization, and especially for spray guns for compressed gas atomization.

[0066] The substrate and spray gun according to the invention can in particular have or be assembled with the following additional components: a handle, an upper gun body, a compressed gas connector, a paint needle, a trigger for opening a gas valve and for moving the paint needle outward from the material outlet of the material nozzle, a circular-spray width adjustment device for setting the ratio of atomizing gas and angular structure gas to form a paint jet, a gas micrometer for setting the spray pressure, a material quantity adjustment device for setting the maximum material volume flow, a material connector, a paint channel for guiding the material to be sprayed from the material inlet to the material outlet, a hook, and / or an analog or digital pressure measuring device. However, the substrate and spray gun can also have other components as in the prior art. The paint spray gun can be designed as a flow cup spray gun with a paint cup arranged on the gun body, wherein the material to be sprayed flows substantially by gravity or by negative pressure from the paint cup into the paint channel at the front end of the material nozzle and flows through the paint channel. However, the spray gun can also be a side cup spray gun, wherein the paint cup is laterally disposed at the gun body, and wherein the material is also conveyed by gravity and by negative pressure at the front end of the material nozzle of the gun. However, the spray gun can also be a suction cup spray gun or a hanging cup spray gun with a paint cup arranged below the gun body, where the material to be sprayed is drawn from the paint cup by a general negative pressure, especially by utilizing the Venturi effect. Furthermore, the spray gun can be designed as a pressure cup gun, where the cup is arranged below, above, or laterally on the gun body and pressure is applied, subsequently forcing the material to be sprayed out of the cup. Additionally, it can be a canister spray gun, where the material to be sprayed is delivered to the spray gun from the paint cup via a hose or via a pump. Attached Figure Description

[0067] The invention will now be described in detail with reference to 18 accompanying drawings. These drawings show: Figure 1The portion of a spray gun having a gas disperser ring according to the prior art disclosed in Chinese Utility Model Document ZL 2014 2 0431026.7 is shown in an exploded view. Figure 2 A top view of the head region of the base of a spray gun in the prior art disclosed in the proposed Chinese utility model document is shown. Figure 3 A cross-sectional view of the head region of a prior art spray gun disclosed in Chinese utility model document ZL 2016 2 0911120.1 is shown. Figure 4 An exploded view of one embodiment of the spray gun according to the present invention is shown; Figure 5 A cross-sectional view is shown of one embodiment of a substrate for a spray gun according to the present invention; Figure 6 A cross-sectional view of the head region of a substrate for a spray gun according to an embodiment of the present invention is shown; Figure 7 A perspective view of the head region of a substrate for a spray gun according to an embodiment of the present invention is shown; Figure 8 A perspective view showing a nozzle for use in one embodiment of a spray gun according to the invention, or an embodiment of a nozzle used with a substrate for a spray gun according to the invention; Figure 9 Shown from the other side Figure 8 A perspective view of an embodiment of the nozzle; Figure 10 Showing the view from the rear Figure 8 A view of an embodiment of the nozzle; Figure 11 Show Figure 8 A cross-sectional view of an embodiment of the nozzle; Figure 12 Showing has Figure 8 A cross-sectional view of the head region of an embodiment of the nozzle according to a substrate according to the invention or an embodiment of the spray gun according to the invention; Figure 13 A perspective view is shown of a second embodiment of a nozzle used in one embodiment of a spray gun according to the invention, or used with a base according to the invention for a spray gun; Figure 14 Shown from the other side Figure 13 A perspective view of an embodiment of the nozzle; Figure 15 Shown from the rear Figure 13 A view of an embodiment of the nozzle; Figure 16 Show Figure 13A cross-sectional view of an embodiment of the nozzle; Figure 17 An embodiment of the spray gun according to the invention is shown or has Figure 13 A cross-sectional view of the head region of an embodiment of the nozzle according to a substrate based on the present invention; and Figure 18 A perspective view of a portion of an embodiment of the substrate according to the present invention is shown. Detailed Implementation

[0068] According to existing technology, spray guns 100, especially paint spray guns Figure 1 The portion shown has a base 102 with different attachments. A gas disperser ring 104 is shown, which can be disposed at the head region 103 of the base 102. For this purpose, the gas disperser ring 104 has at least one, in the present example two retaining pins 106a and 106b, which are inserted into two corresponding retaining pins 106a and 106b. Figure 2 The blind holes 108a and 108b shown are used to secure the diffuser ring 104 to the nozzle head or the head region 103 of the base 102, such that the wall 107 of the gas diffuser ring 104 is sealed against the front surface 110 of the head region 103 of the base 102, as shown in... Figure 3 As shown in the image. Figure 3 The head region 103 shown is disclosed in Chinese Utility Model Document ZL 2016 2 0911120.1. Here, the atomized gas outlet 114 of the front surface 110 of the head region 103 of the substrate 102 is located within the wall 107 of the gas disperser ring 104. Atomized gas flows from the atomized gas outlet 114 into the inner gas dispersion chamber 116, which is formed by the gas disperser ring 104 and the substrate 102. The corner structure gas outlet 112 in the front surface 110 of the head region 103 of the substrate 102 is located outside the wall 107 of the gas disperser ring 104. Corner structure gas flows from the corner structure gas outlet 112 into the outer gas dispersion chamber 118 of the gas disperser ring 104.

[0069] On the surface within the wall portion 107, the gas disperser ring 104 has a plurality of through-holes 120 distributed around its circumference, through which atomized gas flows out from the internal gas dispersion chamber 116. The atomized gas flows from the through-holes 120 to a disc 124 integrally arranged at the paint nozzle 112, which is sealed against the wall portion 109 of the gas disperser ring 104, wherein the wall portion 109 is arranged on the side of the gas disperser ring 104 opposite to the front face 110 of the head region 103 of the substrate 102. The disc 124 has a plurality of through-holes 126 distributed around its circumference. The gas flowing through the through-holes 126 then flows through an annular gap 130 between the central opening of the air cap 132 and the front end of the paint nozzle 122, the front end being configured as a small plug.

[0070] The outer gas dispersion chamber 118 of the gas disperser ring 104 forms a gap with the outer wall portion 134 on the head region 103 of the base 102, through which angular structure gas flows from the outer gas dispersion chamber 118. From there, the gas flows into the angular structure gas delivery channel in the air cap 132 and subsequently into the angular structure gas through-hole 136, from which it exits.

[0071] Figure 4 An exploded view of an embodiment of a spray gun 1 according to the invention, or an embodiment of a substrate 2 according to the invention with accessories, is shown. The spray gun 1 has a cup 3 for receiving and dispensing the material to be sprayed, wherein the cup includes a cover 3b having a valve plug 3a, a cup body 3c, and a plate-type screen 3d. Furthermore, the spray gun 1 may include a material quantity adjustment device 11, a gas micrometer 13, a circular-spray width adjustment device 9, a trigger system 7 consisting of a trigger and a fixing mechanism, and a gas connector, which may be configured as a standard connector 4a or a hinged connector 4b. A nozzle assembly consisting of a nozzle 24 may be arranged in the head region 6 of the substrate 2, the nozzle including a material nozzle 40. The nozzle assembly may also include an air cap 76, which may be fixed, particularly screwed, onto the head region 6 via a gas nozzle ring 74. The head region 6, nozzle 24, and air cap 76 are arranged coaxially with the gas nozzle ring 74 along axis Z, or are capable of being arranged along axis Z, which is the aforementioned central or longitudinal axis of the head region 6 of the base 2, the central or longitudinal axis of the material nozzle 40, the central or longitudinal axis of the upper part of the base 2, and the central or longitudinal axis of the receiving opening for accommodating the material amount adjustment device 11.

[0072] exist Figure 5 The image shows the use of Figure 4 A cross-sectional view of the spray gun according to an embodiment of the substrate of the present invention, wherein, passing from top to bottom... Figure 4The section is completed along axis Z. The substrate 2 has multiple through holes; in particular, multiple through holes are arranged along axis Z in the upper portion of the substrate 2, which is here the central or longitudinal axis mentioned above in the head region 6 of the substrate 2. In this embodiment, this axis is equal to... Figure 4 The material nozzle 40 can be arranged on or within the substrate 2 at its center or longitudinal axis, and is equivalent to a container for... Figure 4 The material quantity adjustment device 11 shown in the example has a receiving opening 82 at its center or longitudinal axis.

[0073] When described as above: the front end of one wall portion is positioned rearward relative to the front end of another wall portion along an axis, then the axis referred to is axis Z. For example, in Figure 5 As can be seen, the intermediate wall portion 12 is clearly positioned rearward relative to the outer wall portion 14. Here, the jetting direction or the substrate 2 can be arranged with... Figure 4 The side of the material nozzle 40 is considered "front", and the opposite side, which is the side with the receiving opening 82 or the opposite direction, is considered "rear". The term "rear" relative to the front end of the outer wall 14 along the axis Z means that the front end of the outer wall 14 is further forward than the front end of the intermediate wall 12.

[0074] In the current embodiment, the inner wall portion 10 is positioned only slightly rearward relative to the intermediate wall portion 12.

[0075] exist Figure 5 Only a single atomizing gas channel 64 is visible in the cross-section, along with a corner-structured gas channel 66 that intersects with a second corner-structured gas channel. A portion of the circular diffusion jet gas dispersion chamber 68 is also shown in the cross-sectional view.

[0076] Figure 6 A cross-sectional view is shown of a portion of an embodiment of the substrate 2 according to the invention for use in a spray gun 1. Figure 5 The image is shown in another cross-sectional view. Figure 6 The section shown is a re-penetration. Figure 4 The axis Z in the middle and along the perpendicular to Figure 5 The sectioning plane used was employed to complete the task. In the current... Figure 6As can be seen, the inner wall portion 10 of the head region 6 of the base 2 of the spray gun 1 is positioned rearward by a distance d4 relative to the intermediate wall portion 12 along the axis Z. The intermediate wall portion 12 is also positioned rearward by a distance d3 relative to the outer wall portion 14 along the axis Z. In other words, the outer wall portion 14 extends beyond the intermediate wall portion 12, and the intermediate wall portion extends beyond the inner wall portion 10. The inner wall portion 10 and the outer wall portion 12 define a first gas dispersion cavity 60, and the intermediate wall portion 12 and the outer wall portion 14 define a second gas dispersion cavity 62. The gas dispersion cavities 60 and 62 are open forward, i.e., in the spray direction, and are defined rearwardly, at least partially, by a first front surface 16 or a second front surface 18. In the current embodiment, a groove 19 is provided in the second front surface 18, and the gas dispersion cavity 62 is partially defined rearwardly by the bottom surface of the groove instead of the second front surface 18. Therefore, the gas dispersion cavity 62 is partially defined rearwardly by the second front surface 18 and partially by the bottom surface of the groove 19. The spacing d5, i.e., the depth of the groove 19, i.e., the distance between the bottom surface of the second front surface 18 and the groove 19, can be, for example, about 1.5 mm to 3.0 mm. The spacing d1 between the first front surface 16 and the front end of the outer wall portion 14 is preferably between 8 mm and 12 mm, and particularly preferably between 9 mm and 11 mm. The spacing d2 between the second front surface 18 and the front end of the outer wall portion 14 is preferably between 4 mm and 6 mm. The intermediate wall portion 12 is currently positioned relative to the outer wall portion 14 along the Z axis with a spacing D3, which is preferably about 2 mm to 4 mm. The inner wall portion is preferably positioned only 0.1 mm to 1.0 mm behind the intermediate wall portion 12. Here, it is the spacing d4. The head region 6 of the base according to the invention is in Figure 6 The embodiments shown have for Figure 6 The nozzle seal has mating sealing surfaces 84 (not shown). The distance d6 between the mating sealing surfaces 84 and the first front surface 16 is preferably about 1.5 mm to 3.0 mm. The first front surface 16 is positioned rearward relative to the second front surface 18 along the Z-axis. In the present embodiment, the distance d7 between the front surface 16 and the second front surface 18 is about 4 mm to 6 mm. The aforementioned dimensions or combinations of dimensions have been proven advantageous for good atomization quality in spraying experiments.

[0077] exist Figure 7 The middle shows Figure 5 and Figure 6A perspective view of an embodiment of the substrate according to the present invention is shown. In particular, the groove 19 in the second front side 18 is clearly visible here. The width of the groove 19 is approximately the same as the width of the second front side 18. The width of the groove 19 or the second front side 18 can be understood here as the radial extension of the head region 6 of the substrate 2, or also as the radial spacing between the intermediate wall portion 12 and the outer wall portion 14. The groove 19 extends circumferentially over approximately 50% of the circumference of the second front side 18, i.e., approximately 180% in this case. In the present embodiment, the inner wall portion 10, the intermediate wall portion 12, and the outer wall portion 14 are each designed to be circular and are arranged concentrically with each other and coaxially with axis Z in the previous figures. Axis Z extends through the axis of rotation of the wall portion, which extends parallel to axis Z.

[0078] Here, the inner wall portion 10 has an internal thread 70. Figure 7 The nozzle, not shown, and especially the material nozzle commonly referred to as a paint nozzle, can be screwed into the internal thread. The outer wall portion 14 here has an external thread 72. Figure 7 The gas nozzle ring, not shown, can be screwed onto the head region 6 of the base 2 together with the air cap via an external thread. The intermediate wall portion 12 does not have a thread here. However, it is conceivable that the intermediate wall portion 12 may also have an internal or external thread. Furthermore, it is conceivable that the outer wall portion 14 has an internal thread for screwing in components, especially the air cap, and the inner wall portion 10 has an external thread for screwing on components, especially the nozzle.

[0079] The first front panel 16 has two internal gas outlets 20a and 20b, and the second front panel 17 has two external gas outlets 22a and 22b. The diameters of the gas outlets 20a, 20b, 22a, and 22b correspond almost to the width of the front panels 16 and 18 or the slots 19 into which they are placed. In this way, the available space can be fully utilized to maximize the gas throughput.

[0080] Figure 8 A perspective view is shown of a nozzle in an embodiment of a spray gun according to the invention, or a nozzle used with an embodiment of a substrate according to the invention for a spray gun, or also an embodiment of a nozzle 24 for use in a method according to the invention. The nozzle 24 can have: at least one material nozzle 40 having a material outlet 28 and a section for abutting a tool, here an external hexagonal profile 41; and a disc element 32 having a front surface 34 and a conical surface 35. The front surface 34 here has a plurality, particularly 7 to 9, through openings 36 distributed circumferentially. The material nozzle 40 and the disc element 32 are preferably integrally formed. A first impact disc 30 is arranged thereon, preferably non-removably arranged, and particularly preferably press-fitted thereon. A [missing information - likely a conical surface] is arranged on the first impact disc, preferably integrally arranged. Figure 9The second impact disc 42 is visible in the image. The second impact disc is disposed on the side of the first impact disc 30 opposite to the material outlet 28. Like the first impact disc 30, the second impact disc 42 is also annularly formed with an inner and outer circumference. The inner circumference of the second impact disc 42 does not contact the external thread 46 of the material nozzle 40 in the radial direction, resulting in a gap between the inner circumference of the second impact disc 42 and the external thread 46 of the material nozzle 40. The second impact disc 42 is spaced apart from the through opening 36 along the axis, i.e., along the center or longitudinal axis of the nozzle 24. The second impact disc 42 almost completely covers the through opening 36 in the radial direction, as shown in... Figure 10 That's what you can see very well in the middle. Furthermore, in... Figure 10 The material outlet 28 and the impact surface 30a of the first impact disc 30 are visible. Preferably, the disc element 32 has a groove or slot on its side opposite to the material outlet 28, in which a through opening 36 is arranged. As a result, the distance between the side of the disc element 32 opposite to the material outlet 28 and the side of the second impact disc 42 facing that side is increased, and the gas flowing into this area is provided with more volume for dispersion.

[0081] Figure 11 The construction of nozzle 24 is shown in cross-section. It can be seen that the material nozzle 40 is integrally formed with its material outlet 28 and disc element 32. Disc element 32 has a surrounding groove 33 on its side facing away from material outlet 28, which facilitates or simplifies the pressing of the first impact disc 30 onto the disc element 32. The first impact disc 30 has an inner circumference and an outer circumference, wherein the outer circumference of the first impact disc 30 is larger than the outer circumference of the disc element 32. The inner circumference of the first impact disc 30 approximately reaches the through opening 36 of the disc element 32. A second impact disc 42 is integrally arranged on the first impact disc 30. A flange 43 can be arranged between them. The first impact disc 30, the second impact disc 32, and the possible flange 43 form a Z-shape here. The first impact disc 30 can have a gap on its side facing material outlet 28, especially in the region of its inner circumference, thereby forming a stepped shape that creates a contact area between the first impact disc 30 and the disc element 32. Here, the disc element 32 also has a step on its side away from the material outlet 28, especially in the outer peripheral region, which forms the contact area between the first impact disc 30 and the disc element 32.

[0082] The material nozzle 40 is equipped with a gas guide disc 38, which is also non-removably connected to the material nozzle 40, and can be pressed tightly. Furthermore, the nozzle 24 here has a nozzle seal 44, the purpose of which will be explained below. The nozzle seal 44 is preferably made of plastic and is preferably replaceably connected to the material nozzle 40. Figure 11 The external thread 46 of the material nozzle 40 is also shown.

[0083] Figure 12 The head region 6 of the spray gun according to the invention or the substrate according to the invention is shown in one embodiment. Figures 8 to 11 The nozzle embodiment is shown in a cross-sectional view in its assembled state. The nozzle 24, which is integrally formed by the material nozzle 40, disc element 32, first impact disc 30, second impact disc 42, gas guide disc 38, and nozzle seal 44, is screwed into the base or its head region via the threads described above. Here, a stop is formed by the first impact disc 30, particularly its impact surface 30a, and the intermediate wall 12 of the head region 6 of the base. The impact surface 30a of the first impact disc 30 serves as a sealing surface, and the intermediate wall 12, with its front end, serves as a mating sealing surface, with the impact surface 30a sealingly abutting against the mating sealing surface. Alternatively or additionally, the outer surface of the second impact disc 42 or the outer surface of the flange 43 sealingly abuts against the inner surface of the intermediate wall 12 between the first and second impact discs 30 and 42.

[0084] With nozzle 24 screwed in, nozzle seal 44 is pressed against Figure 6 The mating sealing surface 84 shown in the figure seals the area between the area of ​​the spray gun that guides the material, especially the cam channel in the substrate and the hollow section of the material nozzle 40 that guides the material to be sprayed, relative to the area of ​​the spray gun that guides the gas.

[0085] In the loaded state, the first impact disc 30 forms a gap 86 with the outer wall portion 14, which is preferably an annular gap with a substantially constant width. The second impact disc 42 forms another gap 88 with the inner wall portion 10, which is also preferably an annular gap with a substantially constant width.

[0086] The gas nozzle ring 74 can be threaded onto the head region 6 of the base body as mentioned above. An air cap 78 is arranged in the gas nozzle ring 74, wherein the air cap 78 is secured in the first direction by means of a flange 90, which abuts against a protrusion on the inner surface of the gas nozzle ring 74. The air cap 78 is defined in the opposite direction by a safety ring 89, wherein the safety ring is located in a groove 91 in the air cap 78 and a void in the inner surface of the gas nozzle ring 74. For better identification only, the safety ring 89 is currently... Figure 12 The locking ring 89 is shown outside the groove 91, and it is not necessary for the locking ring 89 to be completely within the groove 91. For example, the locking ring 89 can be polygonal, such that it is only partially located within the circular groove 91.

[0087] As in Figure 7As can be seen, in the current embodiment of the substrate according to the invention, the first front surface 16 has two gas outlets 20a and 20b or 22a and 22b respectively between the inner wall portion 10 and the intermediate wall portion 12, and the second front surface 18 has two gas outlets 20a and 20b or 22a and 22b respectively between the intermediate wall portion 12 and the outer wall portion 14. (See reference...) Figure 12 It can also be seen that the gas leaving between the inner wall portion 10 and the intermediate wall portion 12 from the two internal gas outlets 20a and 20b first flows onto the second impact disc 42. Due to the narrowing portion in the shape of the gap 88, the gas is dispersed around the circumference of the gas dispersion chamber between the inner wall portion 10 and the intermediate wall portion 12. The gas flow passes through the gap 88 and is thus throttled before flowing through the through opening 36 of the disc element 32. The gas leaving the through opening 36 in a specific manner flows onto the gas guiding element 38, whereby the gas is dispersed planarly, homogenized, and easily throttled again through the small narrowing portion between the gas guiding element 38 and the inner surface of the air cap 78. The gas then flows from the air cap cavity 80 between the air cap 78 and the material nozzle 40 through the gap, especially the annular gap, which is formed by the front end of the material nozzle 40 extending from the inside into the central opening 79 in the air cap 78. The gas flowing from the gap atomizes the material to be sprayed, which flows from the material delivery device through the paint channel in the base of the spray gun and the hollow section of the material nozzle 40, thereby forming a so-called jet stream. The gas having the flow path just described is therefore called atomizing gas. The two internal gas outlets 20a and 20b between the inner wall portion 10 and the intermediate wall portion 12 can be called atomizing gas outlets, the gas channel located behind them is called atomizing gas channel, and the gas dispersion chamber defined by the inner wall portion 10 and the intermediate wall portion 12 can be called atomizing gas dispersion chamber. The area through which the atomizing gas flows can be called the atomizing gas region.

[0088] The gas flowing out from the two external gas outlets 22a and 22b first flows onto the first impact plate 30, and the gas outlet is located in the substrate according to the invention. Figure 12 Although present in the embodiments shown, in Figure 7The gas is particularly well visible in the middle. Due to the narrowing of the gap 86, the gas is dispersed between the intermediate wall 12 and the outer wall 14 on the circumference of the gas dispersion chamber. The gas flow passes through the gap 86 and is thus throttled. Advantageously, the gas then flows into the intermediate chamber 92 and into the corner structure gas delivery channel 78a, entering the corner structure of the air cap 78. From here, the gas flows out from the corner structure gas through-hole 78b and onto the aforementioned jet stream, deforming it. In particular, the so-called corner structure gas flowing out from the corner structure gas through-hole 78b in the diameter-opposite corner structure of the air cap 78 compresses the jet stream on two opposite sides, the jet stream originally having a circular cross-section, thus forming a so-called diffuse jet stream. The amount of corner structure gas flowing out from the corner structure gas through-hole 78b, or the amount of gas that has already flowed out from the external gas outlets 22a and 22b, can be exemplarily determined by... Figure 4 The circular spray pattern adjustment device 9 shown is used for setting, wherein the gas outlet can be referred to as the corner structure gas outlet. If the corner structure gas is reduced to zero or almost zero, the spray gun produces a so-called circular beam with a circular cross-section. The gas passage behind the so-called corner structure gas outlet can be referred to as the corner structure gas passage, the gas dispersion chamber defined by the intermediate wall portion 12 and the outer wall portion 14 is referred to as the corner structure gas dispersion chamber, and the area through which the corner structure gas flows is referred to as the corner structure gas region. In order to seal the corner structure gas region relative to the environment, a sealing element 87 can be provided between the gas nozzle ring 74 and the head region 6.

[0089] The so-called control opening 79a can be opened into the front face of the air cap 78, radially outside the central opening 79. Gas exiting from the control opening 79a affects the corner structure gas, particularly reducing the impact of the corner structure gas on the jet stream. Furthermore, the so-called control gas protects the air cap 78 from contamination by carrying paint droplets away from the air cap 78. In addition, the control gas contributes to further atomization of the jet stream. The control gas also acts on the circular jet stream and causes minor pre-deformation, as well as additional atomization.

[0090] As in Figure 12 As can be clearly seen, separation between the atomizing gas region and the corner structure gas region is achieved through the intermediate wall portion 12, the first impact disc 30, the disc element 32, and the air cap 78, particularly through the preferred surrounding tab 78c. The tab 78c here has a conical region that abuts against the conical surface 35 of the disc element 32. This achieves centering of the air cap 78, thereby ensuring that the air cap 78 and the material nozzle 40 are arranged concentrically, and that the aforementioned gap, particularly the annular gap, between the front end of the material nozzle 40 and the air cap 78, which facilitates the exit of the atomizing gas, has a constant width.

[0091] It is clear that, due to the specific design of the substrate according to the invention and the spray gun according to the invention, no additional seals are required to seal between the atomizing gas region and the corner structure gas region. Since the front end of the intermediate wall portion 12 is positioned rearward relative to the front end of the outer wall portion 14, the intermediate wall portion 12 of the substrate according to the invention, which is crucial for sealing between the atomizing gas region and the corner structure gas region, is well protected even when the nozzle 24 is unscrewed. Furthermore, the head region 6 of the substrate according to the invention provides space for the first impact disc 30 through this design, which therefore does not extend beyond the outer wall portion 14. The nozzle head can thus be designed to be extremely compact.

[0092] exist Figures 8 to 12 The nozzle 24 shown is preferably a low-pressure or HVLP nozzle, or a nozzle for use in low-pressure or HVLP nozzle devices, especially for use in the method according to the invention for modifying spray guns, especially paint spray guns.

[0093] Figure 13 A perspective view is shown of a second embodiment of a nozzle used in one embodiment of a spray gun according to the invention, or used in conjunction with one embodiment of a substrate according to the invention for a spray gun, or also used in the method according to the invention. Figures 8 to 12 Compared to the first embodiment shown, the current nozzle 50 does not have a gas guide disc, and the disc element 32 has a larger number of through openings 36 in the front side 34. In other aspects, the spray gun 50 also has a material nozzle 40 with a material outlet 28, and the disc element 32 has a tapered surface 35. Preferably, the disc element 32 has a groove or slot on its side opposite to the material outlet 28, in which the through openings 36 are arranged. Thus, with the nozzle 50 in the inserted state, the distance between the side of the disc element 32 opposite to the material outlet 28 and the first front side 16 of the head region 6 of the substrate 2 is increased, and the gas flowing into this region provides more volume for dispersion.

[0094] exist Figure 14 As can be seen in the image, the first impact disk 31 of the nozzle 50 is constructed differently from the first impact disk 30 of the previously described nozzle 24. The nozzle 50 does not have a second impact disk, and for this purpose has an inner flange 52 and an outer flange 53 and an impact surface 31a located therebetween.

[0095] exist Figure 15 The image shows a view of the nozzle 50 from the rear, illustrating that the through openings 36 are fully exposed, i.e., not obscured or extended beyond by other components of the nozzle 50. The disc element 32 of the nozzle 50 preferably has a greater number of through openings 36, particularly between ten and fourteen.

[0096] The exposed through opening 36 is also Figure 16 As can be seen in the figure, this is a cross-sectional view of the nozzle 50. The material nozzle 40, having an integrally arranged disc element 32 and a preferably replaceable nozzle seal 44, is substantially the same as the material nozzle 40 having the previously described nozzle 24 with a preferably replaceable nozzle seal 44 and an integrally arranged disc element 32. The above-described embodiments regarding these components are correspondingly applied to the nozzle 50. The first impact disc 31, having an inner flange 52, an outer flange 53, and an impact surface 31a located therebetween, is different from the first impact disc 30 of the previously described nozzle 24.

[0097] Figure 17 It shows having Figures 13 to 16 A cross-sectional view of the head region 6 of an embodiment of the nozzle 50 according to a substrate according to the invention, or an embodiment of a spray gun according to the invention. The substrate is... Figure 12 The embodiment shown is illustrated below. In particular, the head region 6 is constructed similarly, and therefore reference can be made to the above-described embodiment. It can be seen that the gap 86 between the outer wall portion 14 and the first impact disc 31 is greater than... Figure 12 The gap is narrower in 86. Figure 12 The head region 6 of the substrate equipped with the previously described nozzle 24 is shown. Since it involves the same substrate having an outer wall 14 of the same size, particularly the same inner diameter, it is obvious that the first impact disk 31 of the nozzle 50 has a larger outer diameter than the first impact disk 30 of the nozzle 24. Regarding... Figure 12 The remaining embodiments of the device shown are also applicable. Figure 17 The device shown in the figure.

[0098] By using the second impact disc and the missing gas guide disc in nozzle 50 compared to nozzle 24, in Figure 17 In the apparatus shown, that is, when using nozzle 50, the atomized gas and... Figure 12 In the device shown, the flow is more strongly throttled when using nozzle 24. As a result, the pressure inside the nozzle, particularly in the air cap chamber 81 between the air cap 78 and the material nozzle 40 when using nozzle 50, is greater than the pressure inside the nozzle, specifically in the space between the air cap 78 and the material nozzle 40 when using nozzle 24. Figure 12 The pressure in the air cap chamber 80 shown in the figure.

[0099] Figures 13 to 17 The nozzle 50 shown is preferably a high-pressure or flexible nozzle or a nozzle used in high-pressure or flexible nozzle devices, especially in methods of converting a spray gun having a first nozzle internal pressure, especially a paint spray gun, into a spray gun having a second nozzle internal pressure, especially a paint spray gun.

[0100] Figure 18A perspective view of a portion of an embodiment of the substrate according to the invention is shown, specifically of the region in which an object can be arranged. Figure 4 The circular spray pattern adjustment device 9 is illustrated in the example. Specifically, in... Figure 18 The interior of the circular diffuser jet gas dispersion chamber 68 can be seen at least partially. As described above, such as Figure 7 The substrate 2 according to the invention, as visible in the diagram, has two atomized gas outlets 20a and 20b and two corner structure gas outlets 22a and 22b in the head region 6. In the head region 6, the two atomized gas outlets 20a and 20b are spaced apart from each other, as are the two corner structure gas outlets 22a and 22b. Atomized gas channels located after the two atomized gas outlets 20a and 20b, i.e., air cap channels terminating in the form of atomized gas outlets 20a and 20b, extend into the circular diffuser jet gas dispersion cavity 68, converging along their paths into the circular diffuser jet gas dispersion cavity 68, and finally meeting at a focal point with one wall of the circular diffuser jet gas dispersion cavity 68. Therefore, the circular diffuser jet gas dispersion cavity 68 has only a single atomized gas channel inlet 20c. The angular gas channels located after the two angular gas outlets 22a and 22b, that is, the gas channels terminating in the form of angular gas outlets 22a and 22b, extend into the circular diffuser jet gas dispersion cavity 68. They converge into the circular diffuser jet gas dispersion cavity 68 along their paths and finally meet at the focal point of one wall of the circular diffuser jet gas dispersion cavity 68. Therefore, the circular diffuser jet gas dispersion cavity 68 has only one angular gas channel inlet 22c.

[0101] The outer contours of the corner structure gas inlet 22c and the atomizing gas channel inlet 20c in the circular diffuser jet gas dispersion cavity 68 can have a flat “8” shape. If the two atomizing gas channels and the two corner structure gas channels are completely superimposed when entering the circular diffuser jet gas dispersion cavity 68, then the atomizing gas channel inlet 20c has essentially the same cross-sectional shape as at least one of the atomizing gas outlets 20a and 20b, and the corner structure gas inlet 22c has essentially the same cross-sectional shape as one of the corner structure gas outlets 22a and 22b.

[0102] Different circular-spray amplitude adjustment devices are known in the prior art, for example from EP 0 706 832 B1 or EP 2451 586 B1. For the substrate according to the invention herein, any type of circular-spray amplitude adjustment device can be used. However, preferably, the circular diffuser jet gas dispersion chamber 68 has a first chamber section and a second chamber section, wherein the second chamber section has a larger diameter than the first chamber section. The corner structure gas channel of the substrate 2 opens into the first chamber section, i.e., the corner structure gas channel inlet 22c is located in the first chamber section. The atomizing gas channel of the substrate 2 opens into the second chamber section, i.e., the atomizing gas channel inlet 20c is located in the second chamber section. These sections form steps, and a disc or circular-spray amplitude adjustment device can be placed on the steps to close the first chamber section, thereby preventing gas from being delivered to the corner structure gas channel inlet 22c and thus to the corner structure gas channel. In this configuration, gas is supplied only to the atomizing gas channel inlet 20c and the associated atomizing gas channel during spray gun operation. The spray gun produces a circular jet with a substantially circular cross-section because the corner gas does not act laterally on the jet. For example, by means of a rotating mechanism, the disc of the circular-spray width adjustment device can preferably be moved steplessly away from the step between the first and second chamber sections of the circular diffuse jet gas dispersion chamber 68, with the appropriate disc being released into the first chamber section in the substrate 2 and then into the corner gas channel inlet 22c and the gas delivery to the corner gas channel. The farther the disc moves from the step, the more gas flows through the corner gas channel and out of the corner gas orifice, and the more jets are laterally compressed together, thereby producing a finer diffuse jet.

[0103] Finally, it should be noted that the described embodiments only depict a limited selection of feasible implementations and therefore do not limit the invention.

Claims

1. A spray gun (1), comprising: The system comprises at least one substrate (2), a nozzle (24, 50) having at least one material nozzle (40), an air cap (76, 78), a first air guiding region and a second air guiding region, wherein the first air guiding region guides gas for atomizing the material to be sprayed, and the second air guiding region guides gas for influencing the jet stream, wherein the substrate (2) has at least one head region (6) for accommodating the nozzle assembly, wherein the head region (6) has at least one inner wall portion (10), an outer wall portion (14) and an intermediate wall portion (12) disposed between the inner wall portion and the outer wall portion, wherein the wall portion is circumferentially and integrally formed with the substrate (2). Wherein, the front end of the intermediate wall portion (12) is positioned rearward relative to the front end of the outer wall portion (14) along the axis (Z), and wherein the first air guiding region and the second air guiding region are at least partially separated by the intermediate wall portion (12) of the substrate (2), the disc element (32) integrally arranged on the material nozzle (40), at least one impact disc (30, 31, 42) arranged on the material nozzle (40), and at least a portion of the air cap (76, 78), characterized in that the inner wall portion (10), the intermediate wall portion (12) and the outer wall portion (14) are each designed to be circular and arranged concentrically with each other.

2. The spray gun (1) according to claim 1, characterized in that, The spray gun (1) is a paint spray gun.

3. The spray gun (1) according to claim 1, characterized in that, The impact discs (30, 31, 42) are arranged on the material nozzle (40) in a non-removable manner.

4. The spray gun (1) according to any one of claims 1 to 3, characterized in that, The front end of the intermediate wall portion (12) is positioned 2 mm to 4 mm behind the front end of the outer wall portion (14) along the axis (Z).

5. The spray gun (1) according to any one of claims 1 to 3, characterized in that, The inner wall portion (10) and the intermediate wall portion (12) define a first gas dispersion chamber (60), and the intermediate wall portion (12) and the outer wall portion (14) define a second gas dispersion chamber (62).

6. The spray gun (1) according to any one of claims 1 to 3, characterized in that, A first front surface (16) is arranged between the inner wall portion (10) and the intermediate wall portion (12), and a second front surface (18) is arranged between the intermediate wall portion (12) and the outer wall portion (14). The first front surface (16) has at least a first distance (d1) along the axis (Z) from the front end of the outer wall portion (14), and the second front surface (18) has at least a second distance (d2) along the axis (Z) from the front end of the outer wall portion (14), and the first distance (d1) is greater than the second distance (d2).

7. The spray gun (1) according to claim 6, characterized in that, The first spacing (d1) is 9 mm to 11 mm, and the second spacing (d2) is 4 mm to 6 mm.

8. The spray gun (1) according to claim 6, characterized in that, At least the first front side (16) and / or the second front side (18) have a groove (19) at least in a localized area.

9. The spray gun (1) according to claim 8, characterized in that, The second front surface (18) has at least a partial groove (19) having a bottom surface, wherein the bottom surface of the groove (19) is at a third distance from the front end of the outer wall portion (14) along the axis (Z), and the third distance is less than the first distance (d1) of the first front surface (16) from the front end of the outer wall portion (14).

10. The spray gun (1) according to claim 8, characterized in that, The width of the groove (19) corresponds to the width of the first front side (16) or the second front side (18).

11. The spray gun (1) according to claim 8, characterized in that, The groove (19) extends circumferentially over 25% to 75% of the circumference of the first front face (16) or the second front face (18).

12. The spray gun (1) according to claim 11, characterized in that, The groove (19) extends circumferentially over 45% to 55% of the circumference of the first front face (16) or the second front face (18).

13. The spray gun (1) according to claim 6, characterized in that, The first front side (16) has at least one internal gas outlet (20a, 20b), and the second front side (18) has at least one external gas outlet (22a, 22b).

14. The spray gun (1) according to claim 13, characterized in that, The first front side (16) has two internal gas outlets (20a, 20b), and the second front side (18) has two external gas outlets (22a, 22b).

15. The spray gun (1) according to claim 13, characterized in that, At least one of the internal gas outlets (20a, 20b) of the first front side (16) extends at least partially over at least 85% of the width of the first front side (16), and at least one of the external gas outlets (22a, 22b) of the second front side (18) extends at least partially over at least 85% of the width of the second front side (18).

16. The spray gun (1) according to claim 6, characterized in that, The substrate (2) has at least two atomizing gas channels (64) extending from the first front surface (16) into a circular diffuser jet gas dispersion cavity (68), and / or the substrate (2) has at least two corner structure gas channels (66) extending from the second front surface (18) into a circular diffuser jet gas dispersion cavity (68), wherein the atomizing gas channels (64) are spaced apart from each other in the region of the first front surface (16) and at least partially intersect in the region of the circular diffuser jet gas dispersion cavity (68), and / or wherein the corner structure gas channels (66) are spaced apart from each other in the region of the second front surface (18) and at least partially intersect in the region of the circular diffuser jet gas dispersion cavity (68).

17. The spray gun (1) according to any one of claims 1 to 3, characterized in that, The front end of the inner wall portion (10) is positioned rearward relative to the front end of the intermediate wall portion (12) along the axis (Z).

18. The spray gun (1) according to claim 17, characterized in that, The front end of the inner wall portion (10) is positioned 0.4 mm to 0.6 mm behind the front end of the intermediate wall portion (12) along the axis (Z).

19. The spray gun (1) according to any one of claims 1 to 3, characterized in that, The inner wall portion (10) has an outer diameter of 13 mm to 15 mm, the intermediate wall portion (12) has an outer diameter of 22 mm to 24 mm, and the outer wall portion (14) has an outer diameter of 33 mm to 35 mm.

20. The spray gun (1) according to any one of claims 1 to 3, characterized in that, The inner wall portion (10) has an inner diameter of 11 mm to 13 mm, the intermediate wall portion (12) has an inner diameter of 20 mm to 22 mm, and the outer wall portion (14) has an inner diameter of 31 mm to 33 mm.

21. The spray gun (1) according to any one of claims 1 to 3, characterized in that, The inner wall portion (10) has internal threads (70) at least in some parts, and the outer wall portion (14) has external threads (72) at least in some parts.

22. The spray gun (1) according to any one of claims 1 to 3, characterized in that, The nozzles (24, 50) are arranged in or on the substrate (2) such that a second gap (88) is formed between the inner wall portion (10) and at least one of the impact discs (30, 31, 42).

23. The spray gun (1) according to claim 22, characterized in that, The second gap (88) is the second annular gap.

24. The spray gun (1) according to any one of claims 1 to 3, characterized in that, At least one of the impact discs (30, 31, 42) has at least one sealing surface that is sealed against the mating sealing surface of the intermediate wall portion (12) of the substrate (2).

25. The spray gun (1) according to claim 24, characterized in that, At least one of the impact discs (30, 31, 42) has at least one sealing surface that is sealed against the front end of the intermediate wall portion (12) of the substrate (2).

26. The spray gun (1) according to any one of claims 1 to 3, characterized in that, At least one of the impact discs (30, 31, 42) is formed by a first segment and a second segment, the first segment and the second segment together forming a step, and the outer diameter of the step corresponds to the inner diameter of the intermediate wall portion (12) of the base (2).

27. A method for converting a spray gun (1) having a first nozzle internal pressure into a spray gun (1) having a second nozzle internal pressure, wherein, The spray gun having a first nozzle internal pressure and the spray gun having a second nozzle internal pressure are spray guns according to any one of claims 1 to 26, wherein the first nozzle internal pressure is greater than the second nozzle internal pressure, characterized in that the method includes at least the following steps: a. Remove the high-pressure nozzle device from the base (2) of the spray gun (1) or remove the high-pressure nozzle device from the base of the spray gun, wherein the high-pressure nozzle device has at least one nozzle, the nozzle has a material nozzle (40), the material nozzle has a hollow section for guiding the material to be sprayed through and a material outlet (28). b. The low-pressure nozzle device is disposed in or on the substrate (2) of the spray gun (1), wherein the low-pressure nozzle device has at least one nozzle having a material nozzle (40) having a hollow section for guiding the material to be sprayed through and a material outlet (28).

28. The method according to claim 27, characterized in that, The nozzle of the high-pressure nozzle device, removed from the base (2) of the spray gun (1) or from the base of the spray gun, further has a disc element (32) disposed on the outer periphery of the hollow section and at least one first impact disc, wherein the first impact disc is disposed on the side of the disc element (32) opposite to the material outlet (28) and has an inner periphery and an outer periphery. The nozzle of the low-pressure nozzle device, disposed on or in the base (2) of the spray gun, further has a disc element (32) disposed on the outer periphery of the hollow section and at least one first impact disc, wherein the first impact disc of the low-pressure nozzle device is disposed on the side of the disc element (32) of the low-pressure nozzle device opposite to the material outlet (28) and has an inner periphery and an outer periphery, and the first impact disc has a second impact disc disposed on the side of the first impact disc opposite to the material outlet (28), wherein the outer periphery of the first impact disc of the nozzle of the low-pressure nozzle device is smaller than the outer periphery of the first impact disc of the nozzle of the high-pressure nozzle device.

29. The method according to claim 27 or 28, characterized in that, The method includes at least the following additional steps: a. Remove the high-pressure air cap disposed on the substrate (2) via a gas nozzle ring (74), wherein the high-pressure air cap has at least one central opening having a first diameter; b. A low-pressure air cap is arranged on the base (2) via the gas nozzle ring (74), wherein the low-pressure air cap has at least one central opening having a second diameter, and wherein the second diameter is larger than the first diameter of the high-pressure air cap.

30. A method for converting a spray gun (1) having a first nozzle internal pressure into a spray gun (1) having a second nozzle internal pressure, wherein, The spray gun having a first nozzle internal pressure and the spray gun having a second nozzle internal pressure are spray guns according to any one of claims 1 to 26, wherein the first nozzle internal pressure is less than the second nozzle internal pressure, characterized in that the method includes at least the following steps: a. Remove the low-pressure nozzle device from the base (2) of the spray gun (1) or remove the low-pressure nozzle device from the base (2) of the spray gun (1), wherein the low-pressure nozzle device has at least one nozzle, the nozzle having a material nozzle (40), the material nozzle having a hollow section for guiding the material to be sprayed through and a material outlet (28). b. The high-pressure nozzle device is disposed in or on the substrate (2) of the spray gun (1), wherein the high-pressure nozzle device has at least one nozzle, the nozzle having a material nozzle (40) having a hollow section for guiding the material to be sprayed through and a material outlet (28).

31. The method according to claim 30, characterized in that, The nozzle of the low-pressure nozzle device, which is removed from the base (2) of the spray gun (1) or from the base of the spray gun, further has a disc element (32) arranged on the outer periphery of the hollow section and at least one first impact disc, wherein the first impact disc is arranged on the side of the disc element (32) opposite to the material outlet (28), the first impact disc having an inner periphery and an outer periphery, and the first impact disc having a second impact disc arranged on the side of the first impact disc opposite to the material outlet (28), and the nozzle of the high-pressure nozzle device, which is arranged on or in the base (2) of the spray gun, further has a disc element (32) arranged on the outer periphery of the hollow section and at least one first impact disc, wherein the first impact disc of the high-pressure nozzle device is arranged on the side of the disc element (32) of the high-pressure nozzle device opposite to the material outlet (28) and has an inner periphery and an outer periphery, and wherein the outer periphery of the first impact disc of the nozzle of the high-pressure nozzle device is larger than the outer periphery of the first impact disc of the nozzle of the low-pressure nozzle device.

32. The method according to claim 30 or 31, characterized in that, The method includes at least the following additional steps: a. Remove the low-pressure air cap disposed on the substrate (2) via a gas nozzle ring (74), wherein the low-pressure air cap has at least one central opening having a first diameter; b. A high-pressure air cap is arranged on the base (2) via the gas nozzle ring (74), wherein the high-pressure air cap has at least one central opening having a second diameter, and wherein the second diameter is smaller than the first diameter of the low-pressure air cap.

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