Compressed air valve seat unit for a paint spray gun

Abstract

The invention relates to a compressed air valve seat unit (10, 51) for a paint spray gun (50), in particular comprising a cage (11, 52), wherein the cage (11, 52) is designed to be mounted within a paint spray gun body (58) between a compressed air supply channel (53) and a broad-jet / round-jet regulating unit (54); the cage (11, 52) has an outlet interface (14) for the flow of compressed air from an inner region (13, 57) of the cage (11, 52) into the broad-jet / round-jet regulating unit (54); the outlet interface (14) is provided over the entire circumference of the lateral surface (15) of the cage (11, 52); and the outlet interface (14) has at least one first row of openings (16), which are distributed over the circumference of the lateral surface (15), and a second row of openings (17), which are distributed over the circumference of the lateral surface (15).

Description

[0001] Compressed air valve seat unit for a paint gun

[0002] The invention relates to a compressed air valve seat unit for a paint gun, and a paint gun.

[0003] Spray guns are generally known in the prior art and are used, for example, in automotive workshops for painting cars. Spray guns serve to atomize flowable material and apply it to a surface. The material to be applied can be either liquid or powder. Spray guns have different airflows that flow within the gun and serve to convey, atomize, and / or shape the paint flow. A compressed air valve seat unit is used as part of an air valve.

[0004] In this context, it has now become apparent that there is a further need to provide a compressed air valve seat unit that enables improved airflow.

[0005] These and other problems, which will be mentioned in the following description or which can be recognized by a person skilled in the art, are solved by the subject matter of the independent claims. The dependent claims further develop the central idea of ​​the present invention.

[0006] According to a first aspect of the present invention, a compressed air valve seat unit for a paint gun is provided, comprising a cage, wherein the cage is arranged to be positioned within a paint gun body between a compressed air supply channel and a wide-spray / round-spray control unit, wherein the cage is arranged to receive an air piston, wherein the cage has a valve seat surface, wherein the valve seat surface is arranged to be in contact with a valve seat counter-surface of the air piston in a first position of the air piston such that a flow of compressed air is prevented, wherein the valve seat surface is arranged to be spaced apart from the valve seat counter-surface of the air piston in a second position of the air piston so that the compressed air flow flows into an interior region of the cage.wherein the cage has an outlet interface for the compressed air flow from the interior of the cage into the wide-spray / round-spray control unit, wherein the outlet interface is arranged over an entire circumference of a lateral surface of the cage so that the cage can be arranged in any orientation within the spray gun body, wherein the outlet interface has at least a first row of openings distributed over the circumference of the lateral surface and a second row of openings distributed over the circumference of the lateral surface.

[0007] According to a second aspect of the present invention, a paint gun is provided comprising a paint gun body, an air piston, a wide-jet / round-jet regulating unit, and a compressed air valve seat unit described in more detail above and below.

[0008] The term "spray gun" refers in particular to a hand-held paint dispensing unit with a trigger for actuating a valve configured to release a flow of paint and / or for actuating a valve configured to release a flow of compressed air. The terms "spray gun," "paint nozzle," or other designations containing the terms "paint" or "paint" are not to be understood as restricting this to these materials. The spray gun according to the invention can, for example, spray paint, adhesive, or varnish, in particular base coat and clear coat, both solvent-based and water-based, as well as liquids for the food industry, wood preservatives, or other liquids. The spray gun in question can be either hand-held or automatic or robotic.Handheld spray guns are primarily used by tradespeople, especially painters, carpenters, and varnishers. Automatic and robotic spray guns are generally used in conjunction with a painting robot or a painting machine for industrial applications. However, it is certainly conceivable to integrate a handheld spray gun into a painting robot or a painting machine. In particular, a spray gun according to the invention, designed as a handheld spray gun, can be configured as a gravity-feed spray gun with a paint cup arranged above the spray gun body, from which the material to be sprayed flows into and through the paint channels essentially by gravity and by negative pressure at the front end of the paint nozzle.The spray gun according to the invention can be a side-feed spray gun in which the paint cup is arranged laterally on the spray gun body, and in which the material is fed to the gun by gravity and by negative pressure at the front end of the material nozzle. The spray gun according to the invention can be designed as a suction or hanging-feed spray gun with a paint cup arranged below the spray gun body, from which the material to be sprayed is drawn out of the cup essentially by negative pressure. The spray gun according to the invention can be designed as a pressure-feed spray gun in which the cup is arranged below, above, or laterally on the spray gun body and is pressurized, whereupon the material to be sprayed is forced out of the cup.The spray gun according to the invention can be a tank gun, in which the material to be sprayed is supplied to the spray gun via a hose from a paint container or via a pump. The spray gun according to the invention can be a low-pressure, in particular an HVLP, gun with a nozzle internal pressure of a maximum of 10 psi or 0.7 bar, thereby achieving transfer rates of more than 65%. The spray gun according to the invention can be a compliant gun that has a nozzle internal pressure of more than 10 psi or 0.7 bar, but also achieves a transfer rate of more than 65%. The spray gun according to the invention can be an air-assisted airless gun. The spray gun according to the invention can be a spray gun of another type.

[0009] The spray gun according to the invention is preferably a so-called "single-axis" spray gun. The air valve axis and the paint valve axis lie on the same axis. The term "paint valve axis" refers in particular to the axis in or on which the paint valve is arranged. The paint valve axis is defined, in particular, by the orientation of a paint needle of the needle valve. The paint valve axis can be the longitudinal axis of the paint needle. The term "air valve axis" refers in particular to the axis in or on which the air valve is arranged. The air valve axis can be the longitudinal axis of at least one component of the air valve, in particular the longitudinal axis of a compressed air valve seat unit and / or the longitudinal axis of a cage of a compressed air valve seat unit, which can form a seat for a sealing element. The air valve axis and the paint valve axis can be coaxial.The air valve axis and the paint valve axis can preferably be the same axis. The paint needle preferably extends along the air valve axis and the paint valve axis. The air valve axis and / or the paint valve axis can be the same as the longitudinal axis of the paint nozzle body. The air valve axis and / or the paint valve axis and / or the longitudinal axis of a paint nozzle body can be coaxial. The air valve can be arranged on the air valve axis and / or the paint valve axis, which can mean that components forming the air valve, in particular a seal and at least part of a compressed air valve seat assembly and / or a cage of a compressed air valve seat assembly, can be arranged around the air valve axis and / or the paint valve axis. The air valve axis and / or the paint valve axis can be the same as the longitudinal axis of a compressed air valve seat assembly and / or a cage of a compressed air valve seat assembly.The air valve axis and / or the paint valve axis can be coaxial with a longitudinal axis of a compressed air valve seat assembly and / or a cage of a compressed air valve seat assembly. The air valve axis and / or the paint valve axis can be the same as the longitudinal axis of an air piston. The air valve axis and / or the paint valve axis can be coaxial with the longitudinal axis of an air piston.

[0010] The compressed air valve seat unit according to the invention can be used in all the aforementioned types of spray guns. The term "spray gun body" refers in particular to a housing designed to arrange and at least partially enclose the components of a spray gun. The spray gun body includes, in particular, a handle. A paint valve, especially a needle valve, is arranged in or on the spray gun body, which is designed to regulate, i.e., to release or close, a flow of paint to the outlet opening of the spray nozzle body. An air valve is also arranged in or on the spray gun body, which is designed to regulate, i.e., to release or close, an air flow.The airflow serves, for example, to atomize the paint stream after it leaves the outlet of the spray nozzle body and / or to carry the paint particles towards the object to be coated and / or to shape the spray pattern. A compressed air connection and a paint connection are arranged in or on the spray gun body. Furthermore, a spray nozzle body is arranged on the spray gun body. The spray gun body has an interface for the spray nozzle body, and the spray nozzle body has a corresponding interface. These interfaces are threaded.The spray gun may include a paint needle, a trigger for opening the air valve and the paint valve, in particular for moving the paint needle out of the paint nozzle outlet, a wide-spray / round-spray control unit for adjusting the ratio of atomizing air to horn air to shape the paint jet, an air micrometer for adjusting the spray pressure, a material flow control device for adjusting the maximum material flow rate, a material connection, paint channels for guiding the material to be sprayed from a material inlet to the material outlet, a hanging hook, and / or an analog or digital pressure measuring device. It may also include other components from the prior art. The spray gun body may be made of plastic or metal.

[0011] The term "compressed air valve seat unit" refers in particular to a part of an air valve. The air valve is located between the compressed air inlet of the spray gun and the air outlet, in particular the air nozzle, of the spray gun. The compressed air valve seat unit is located in particular adjacent to the wide-spray / round-spray control unit. The compressed air valve seat unit is located in particular in a bore in the spray gun body. The compressed air valve seat unit is located in particular in a horizontal bore in the spray gun body that runs coaxially or parallel to the spray direction of the spray gun. The horizontal bore can in particular consist of several bores, in particular several bores with different diameters. The compressed air valve seat unit is located in particular around an air piston of the spray gun.The compressed air valve seat unit is arranged, in particular, coaxially to an air piston of the spray gun. The compressed air valve seat unit is arranged, in particular, around a paint needle of the spray gun. The compressed air valve seat unit is arranged, in particular, coaxially to a paint needle of the spray gun. A paint needle of the spray gun is guided, in particular, within an air piston. An air piston is guided, in particular, along the outer circumference of a paint needle of the spray gun. An air piston is guided, in particular, by the compressed air valve seat unit or the cage of the compressed air valve seat unit, in particular by sealing elements on its inner circumference.

[0012] The term "cage" refers in particular to a part of an air valve, especially a part of the compressed air valve seat assembly. The cage is designed in particular as a hollow cylinder. The cage may in particular be a valve sleeve. The cage has in particular a first interface for arrangement or mounting in the spray gun body. The cage has in particular a thread, in particular an external thread, by means of which the cage can be screwed into the spray gun body. Radially within the threaded section, the cage has in particular a seal, the inner diameter of which seals against an air piston, which is mounted axially displaceably within the cage. On its side opposite the first interface, the cage has a contact surface, in particular a seat, for an air valve or a mating element of an air valve. The contact surface may have a seal.The seal preferably seals downstream between the air piston and the cage. Alternatively or additionally, a seal can be arranged on the air piston. This seal is preferably designed such that it can bear against the contact surface of the cage and seal downstream between the air piston and the cage. A seal can be arranged between the cage and the spray gun body on the outer circumference of the end of the cage opposite the first interface (hereinafter referred to as the rear end). The cage has, in particular, a contour for the engagement of a tool, especially an internal hexagon, by means of which the cage or the compressed air valve seat unit can be screwed into the spray gun body.

[0013] The term "compressed air supply channel" refers specifically to a bore through the handle of the spray gun body, through which air, particularly compressed air, flows from an air supply, especially a hose connection, into an upper part of the spray gun body. In the upper part of the gun body, the compressed air supply channel meets the aforementioned horizontal bore in the spray gun body. An air micrometer may be arranged in the compressed air supply channel. An air micrometer may engage within the compressed air supply channel.

[0014] The wide-beam / round-beam control unit is used to adjust the ratio of atomizing air to horn air for shaping the paint spray. The wide-beam / round-beam control unit may include a bore in the spray gun body. Downstream of this bore are the round-beam air duct for supplying atomizing air and the wide-beam air duct for supplying shaping air. The inlets of the round-beam and wide-beam air ducts are fluidically connected to the bore in the spray gun body. The wide-beam / round-beam control can be achieved via a device that opens or at least partially closes the inlets of the round-beam and wide-beam air ducts. This device may be operated by a rotary knob.Preferably, the bore in the spray gun body has a section with a larger inner diameter and a section with a smaller inner diameter, the transition between the sections comprising a step against which a plate can rest to seal the section with the smaller inner diameter from the section with the larger inner diameter. The section with the smaller inner diameter is preferably fluidically connected to the wide-jet air channel for guiding the molding air. The section with the larger inner diameter is preferably fluidically connected to the circular-jet air channel for guiding the atomizing air. The plate can be moved by means of a rotary knob and thus positioned against and removed from the step to cut off or release the air supply to the wide-jet air channel.The bore of the wide-beam / round-beam control unit, in particular the area with a larger diameter, preferably intersects the aforementioned horizontal bore in the pistol body.

[0015] Preferably, the horizontal bore in the gun body and the bore of the wide-beam / round-beam control unit are fluidically connected, allowing air to flow from the horizontal bore into the bore of the wide-beam / round-beam control unit. Preferably, the cage of the compressed air valve seat unit is arranged above the interface between the bore of the wide-beam / round-beam control unit and the horizontal bore in the spray gun body. The cage has two axial openings at its two ends.

[0016] The air piston is, in particular, an element for transmitting the trigger movement to the paint needle. The air piston is, in particular, an element for moving the paint needle and for opening and closing the needle valve. The air piston is, in particular, an element for opening and closing the air valve. The air piston is, in particular, a hollow body, specifically a hollow body for guiding the paint needle. The paint needle extends through the aforementioned horizontal bore in the paint gun body. The air piston surrounds the paint needle but is not attached to it, allowing the air piston to slide over the paint needle. The air piston preferably has a collar against which a spring rests. In particular, the spring rests against the rear of the collar. In particular, the front of the collar forms a valve seat surface for contact with the valve seat surface of the cage.In particular, a seal arranged on the air piston, especially a seal located on the front of the collar, forms a valve seat counter surface for contact with the valve seat surface of the cage.

[0017] When the trigger is not actuated, the valve seat surface rests against the rear end of the cage and seals an air chamber located upstream of the cage in the horizontal bore against the interior of the cage. When air flows into the spray gun and through the compressed air supply channel into this air chamber, the air cannot flow into the interior of the cage.

[0018] In the region of the rear end of the paint needle, i.e., in the region of the end of the paint needle facing away from the spray direction of the paint gun, a drive element is arranged on the paint needle in such a way that the drive element is not axially displaceable relative to the paint needle. Preferably, the drive element is arranged on the paint needle in such a way that it is also not rotatable about the longitudinal axis of the paint needle.

[0019] When the trigger guard is not actuated, there is a gap between the rear end of the air piston and the front end of the follower. When the trigger guard is not actuated, the rear end of the air piston is axially spaced from the front end of the follower.

[0020] When the trigger is pulled, part of the trigger presses against the front end of the air piston, causing the piston to slide rearward over the paint needle. This moves the valve seat surface away from the valve seat surface of the cage, i.e., the valve seat surface moves out of its seat at the rear of the cage. The air valve is now open. Air can now flow from the air chamber in the horizontal bore into the interior of the cage. The front opening of the cage is closed, so air can only flow from the interior of the cage into the wide-spray / round-spray control unit, or rather into its bore, through the compressed air outlet. The outlet is located around the entire circumference of one of the cage's outer surfaces, allowing the cage to be positioned in any orientation within the spray gun body.The outlet interface has at least a first row of openings distributed around the circumference of the outer surface, and a second row of openings also distributed around the circumference of the outer surface. From the wide-spray / round-spray control unit, at least a portion of the air flows through air channels in the spray gun body to an annular gap formed by a central opening in the air cap and the front end of the paint nozzle. This air flows through the annular gap and atomizes the paint flowing from the nozzle. The air flowing from the annular gap is known as atomizing air. Depending on the setting of the wide-spray / round-spray control unit, a portion of the air flows through air channels in the spray gun body, separate from the aforementioned air channels, into horns in the air cap and out of openings therein, known as horn air openings or horn bores.The so-called shaping air or horn air that emerges there serves in particular to shape the spray jet.

[0021] When the trigger is pulled further after the air valve has opened, the rear end of the air piston presses against the drive pin, which is thereby moved backward. Since the drive pin is axially fixed to the paint needle, the paint needle also moves backward and opens the outlet of the paint nozzle, allowing paint to flow from the outlet and be atomized by the atomizing air.

[0022] The invention is based on the understanding that spray guns of a specific model, with a specific nozzle technology and nozzle size, should all have the same spraying characteristics. For this reason, the components of all these spray guns must be manufactured with as identical dimensions as possible and assembled in the same way. Prior art compressed air valve seat units typically have elongated openings on their outer surface or on the outer surface of the cage of the compressed air valve seat unit, which are separated from each other by webs. These designs have the disadvantage that the orientation of the compressed air valve seat unit or the cage within the spray gun body has a significant impact on the airflow behavior. For example, the compressed air valve seat unit or cage can be...The cage may be accidentally mounted in such a way that a bridge lies in the transition area between the inside of the cage and the wide-beam / round-beam control unit, or within its bore. However, the compressed air valve seat unit or the cage may also be accidentally mounted in such a way that an elongated opening lies in the transition area between the inside of the cage and the wide-beam / round-beam control unit, or within its bore. Such different mounting situations arise from minimally different tightening torques used to screw the cage into the gun body. The airflow and pressure conditions differ significantly between these mounting situations.The compressed air valve seat unit according to the invention allows the cage to be arranged in any orientation within the paint gun body, in particular with respect to the wide-jet / round-jet control unit, especially the bore of the wide-jet / round-jet control unit, whereby the flow and pressure conditions for the air are significantly more constant at different tightening torques with which the cage is screwed into the gun body than with compressed air valve seat units according to the prior art.

[0023] Preferably, the openings of the cage's outlet interface are evenly distributed around the circumference of the lateral surface. In particular, the openings of the first row of openings are evenly distributed around the circumference of the lateral surface, and / or the openings of the second row of openings are evenly distributed around the circumference of the lateral surface.

[0024] Preferably, the first row of openings is arranged offset longitudinally from the second row of openings. In particular, the first row of openings and the second row of openings are not at the same height axially.

[0025] Preferably, the openings of the first row of openings are arranged circumferentially offset from the openings of the second row of openings. Such an offset results in an even lower dependence of the flow and pressure conditions on the orientation of the cage within the spray gun body, particularly with regard to the wide-spray / round-spray control unit, and especially the bore of the wide-spray / round-spray control unit.

[0026] Particularly preferred is the arrangement of the openings of the first row of openings centrally between two openings of the second row of openings in the circumferential direction. This allows for optimal utilization of the surface area. In particular, the ratio of the total area of ​​all openings to the total area of ​​the intervening webs can be maximized. This design further improves the flow cross-section and the independence of the flow and pressure conditions from the cage's orientation.

[0027] Preferably, the outlet interface has a third row of openings. This further improves the independence of the flow and pressure conditions from the orientation of the cage.

[0028] The openings can have, in particular, an oblong, elliptical, or triangular cross-section. Specifically, the openings can have a polygonal, especially a hexagonal, cross-section. This allows for the greatest possible ratio of openings to intervening webs.

[0029] Preferably, each opening has a bore. Preferably, each of the openings has a bore. In particular, the bore has a circular cross-section. This results in better airflow than would be the case with rectangular openings. Preferably, the opening has a chamfer. In particular, the term "chamfer" refers to a beveled surface. Specifically, the chamfer is an inclined surface surrounding the opening. Preferably, each of the openings has a chamfer. The chamfer can be located on the inside and / or on the outside of the cage. The chamfer can taper towards the inside of the cage and / or towards the outside of the cage. Preferably, the chamfer completely surrounds the respective opening. Preferably, the chamfers of adjacent openings form a corner. The chamfers offer aerodynamic advantages.In particular, the chamfer has a straight area and / or a curved area.

[0030] Preferably, the chamfer of the opening in the second row is larger than the chamfer of the opening in the first and third rows. In particular, the chamfers of the openings in the second row extend in the radial and / or axial direction over a larger area than the chamfers of the openings in the first and third rows.

[0031] Preferably, the openings have a substantially identical cross-sectional area. In particular, this means that all openings of the cage's outlet interface have a substantially equal cross-sectional area. The cross-sectional area is particularly preferably between 2 mm². 2 and 6 mm 2 , especially between 4 mm 2 and 5 mm 2 , especially 4.5 mm 2 .

[0032] Preferably, the ratio between the cross-sectional area of ​​an opening and the cross-sectional area of ​​the interior of the cage in the region of the openings is between 0.04 and 0.06. Particularly preferably, the cross-sectional area of ​​an opening is between 2 mm². 2 and 6 mm 2 , especially between 4 mm 2 and 5 mm 2 , especially 4.5 mm 2 , and the cross-sectional area of ​​the interior of the cage in the area of ​​the openings between 60 mm 2 and 100 mm 2 , preferably 87 mm 2 .

[0033] Preferably, the cage is designed as a single piece and / or the cage is made of a plastic material. Preferably, the cage is made of POM. In particular, the cage is injection-molded in one piece. The cage or the compressed air valve seat assembly can have seals, especially sealing rings. These can be injection-molded and / or mounted onto the cage. The cage can be designed as a multi-piece assembly.

[0034] Preferably, the cage has a through-opening for receiving and guiding the air piston and / or the cage has a groove for receiving a seal to seal the cage against the paint gun body. The air piston can be guided on the inner circumference of the cage by means of sealing elements.

[0035] A paint spray gun, in particular the paint spray gun according to the invention, preferably has an air nozzle assembly comprising, in particular, an air cap and an air nozzle ring, wherein the air nozzle ring has at least one locking lug, in particular three locking lugs, which is designed to engage in a groove in the air cap, wherein the locking lug has at least one chamfer. The locking lug is preferably arranged on the inner circumference of the air nozzle ring. For assembly of the air cap and air nozzle ring, the air cap is inserted into the air nozzle ring from the rear. The locking lugs engage in a groove in the air cap, in particular on the outer circumference of the air cap, and secure the air cap in the air nozzle ring in such a way that the air cap is rotatably mounted about a longitudinal axis, but in the axial direction does not fall out of the air nozzle ring on its own.The chamfer allows the locking lugs to disengage more easily from the groove in the air cap and reduces wear on the locking lugs when the air cap is pushed out of the air nozzle ring for disassembly. The features in this paragraph, taken individually, and especially without the features mentioned above, are considered inventive.

[0036] A paint spray gun, in particular the paint spray gun according to the invention, preferably has an air nozzle ring with at least two locking lugs arranged in a non-opposite position, in particular at least two locking lugs arranged in a non-diametrically opposed position, wherein the air nozzle ring in particular has an odd number of locking lugs which are arranged evenly distributed over the inner circumference of the air nozzle ring. When the locking lug emerges from a groove in the air cap during disassembly of the air cap and air nozzle ring, the air nozzle ring moves away from the air cap in the area of ​​the locking lug and / or the air cap moves away from the air nozzle ring in the area of ​​the locking lug.If two locking lugs are arranged opposite each other on the inner circumference of the air nozzle ring, these movements are hindered, and the locking lug may have more difficulty disengaging from the groove in the air cap, and / or the wear of the locking lug increases, and / or the disassembly of the air cap and air nozzle ring becomes more difficult. The features in this paragraph are considered inventive on their own, particularly without the features mentioned above. The features in this paragraph are considered inventive in particular when combined with the features mentioned in the preceding paragraph.

[0037] A paint spray gun, in particular the paint spray gun according to the invention, preferably has an air nozzle ring with at least one locking lug that is spaced axially, in particular along a longitudinal axis, from the front end of the air nozzle ring. This provides, in particular, better protection of the locking lug against damage. The features in this paragraph are considered inventive on their own, especially without the features mentioned above. The features in this paragraph are considered inventive, in particular, together with the features mentioned in the preceding paragraph. The features in this paragraph are considered inventive, in particular, together with the features mentioned before the preceding paragraph.

[0038] The features described above, including those from different embodiments, can also be combined with each other, which can result in synergistic interactions that go beyond the sum of the individual effects.

[0039] The invention is explained below with reference to exemplary embodiments, which are described with reference to the following figures:

[0040] Figure 1 shows an exemplary compressed air valve seat unit according to the invention;

[0041] Figure 2 shows an exemplary paint gun according to the invention or a paint gun with an exemplary compressed air valve seat unit according to the invention;

[0042] Figure 3 shows an air nozzle arrangement of an exemplary paint gun according to the invention.

[0043] Figure 1 shows an exemplary compressed air valve seat assembly 10 according to the invention. The illustrated compressed air valve seat assembly 10 has a cage 11, the cage 11 having a valve seat surface 12, and the cage 11 also having an outlet interface 14 so that a compressed air flow can flow from the interior 13 of the cage 11. The outlet interface 14 is arranged over the entire circumference of a lateral surface 15 of the cage 11. The outlet interface 14 has at least a first row of openings 16 distributed over the circumference of the lateral surface 15 and a second row of openings 17 distributed over the circumference of the lateral surface 15. The first row of openings 16 is arranged offset in the longitudinal direction 18 from the second row of openings 17. The first row of openings 16 has openings 19. The second row of openings 17 has openings 20, 22.The openings 19 of the first row of openings 16 are arranged circumferentially offset from the openings 20, 22 of the second row of openings 17. One opening 19 of the openings of the first row of openings 16 is arranged circumferentially 21 centrally between two openings 20, 22 of the openings of the second row of openings 17. The outlet interface 14 of the compressed air valve seat unit 10 has a third row of openings 23, which are distributed around the circumference of the outer surface 15. The third row of openings 23 has openings 32. The openings 19, 20, 22, 32 each have a bore 24, or are configured as a bore 24. The openings 19, 20, 22, 32 each have a chamfer 25, 26, 27. In the present case, the chamfer 26 of the openings 20, 22 in the second row of openings 17 is larger than the chamfers 25, 27 of the openings 19, 32 in the first row of openings 16 and the third row of openings 23.In the present embodiment, the openings 19, 20, 22, 32 have a substantially identical cross-sectional area. In particular, the openings 19, 20, 22, 32 are of the same size. The openings 19, 20, 22, 32 have an inner diameter 28. The cage 11 has an inner diameter 29 in the region of the openings 19, 20, 22, 32. In the present embodiment, the openings 19, 20, 22, 32 each have an inner diameter 28 of approximately 2.4 mm, which corresponds to a cross-sectional area of ​​4.5 mm². 2 The cage 11, or rather its interior, has an inner diameter 29 of approximately 10.5 mm in the area of ​​openings 19, 20, 22, 32, which corresponds to a cross-sectional area of ​​approximately 87 mm². 2The ratio between the cross-sectional area of ​​an opening 19, 20, 22, 32 and the cross-sectional area of ​​the interior region 13 of the cage 11 in the area of ​​the openings 19, 20, 22, 32 is preferably between 0.04 and 0.06, and approximately 0.05 in the present embodiment. The cage 11 is designed as a single piece and is made of plastic. In particular, it is manufactured in one piece by injection molding. The cage 11 has a groove 31 for receiving a seal, in particular an O-ring. The collars delimiting the groove 31 can have the same diameter. The collars delimiting the groove 31 can have different diameters. In particular, the collar located on the side of the groove 31 facing away from the valve seat surface 12 can have a smaller diameter than the collar located on the side of the groove 31 facing the valve seat surface 12. This facilitates the insertion of the cage 11 into the space shown in Fig.2. Paint gun body 58 shown. The cage 11 has an external thread 33 for screwing the cage 11 into a paint gun body.

[0044] Figure 2 shows an exemplary paint spray gun 50 according to the invention, or a paint spray gun 50 with an exemplary compressed air valve seat unit 51 according to the invention. The compressed air valve seat unit 51 shown in Figure 2 can be configured like the compressed air valve seat unit 10 shown in Figure 1. The compressed air valve seat unit 51 comprises a cage 52, wherein the cage 52 is arranged to be positioned within the paint spray gun body 58 between a compressed air supply channel 53 and a wide-spray / round-spray control unit 54, wherein the cage 52 is arranged to receive an air piston 55, wherein the cage 52 has a valve seat surface 12 as shown in Figure 1, wherein the valve seat surface 12 is arranged to be brought into contact with a valve seat counter surface 56 of the air piston 55 in a first position of the air piston 55 in such a way that a flow of compressed air is prevented, wherein the valve seat surface 12 is arrangedin a second position of the air piston 55, the air piston 55 is spaced apart from the valve seat surface 56 of the air piston 55, so that the compressed air flow flows into an inner region 57 of the cage 52, the cage 52 having an outlet interface 14 shown in Figure 1 for the compressed air flow from the inner region 57 of the cage 52 into the wide-beam / round-beam control unit 54, the outlet interface 14 being arranged over an entire circumference of a cylindrical surface 15 of the cage 52 shown in Figure 1, so that the cage 52 can be arranged in any orientation within the paint gun body 58, the outlet interface 14 having at least a first row of openings 16 shown in Figure 1, which are distributed over the circumference of the cylindrical surface 15, and a second row of openings 17 shown in Figure 1.which are distributed over the circumference of the outer surface 15. In the groove 31 of the cage 52 shown in Figure 1, a seal 59 is arranged to seal the cage 52 against the spray gun body 58. The cage 52 has an external thread 33 shown in Figure 1, by means of which the cage 52 is screwed into the spray gun body 58. Radially within the section with external thread 33, the cage 52 has a seal whose inner diameter seals against the air piston 55. The air piston 55 is mounted to be axially displaceable within the cage 52. A paint needle is also mounted to be axially displaceable within the air piston 55.

[0045] Figure 3 shows an air nozzle assembly 60 of an exemplary paint spray gun according to the invention. The air nozzle assembly 60 comprises, in particular, an air cap 62 and an air nozzle ring 64. The air cap 62 has a central opening 65 which, together with a paint nozzle (not shown in Figure 3), forms an annular gap through which the atomizing air flows out. The air cap 62 further comprises two horns 631, 632. The horns 631, 632 each have three horn openings 63a, 63b, 63c, 63d, 63e, 63f. The horn openings 63a, 63b, 63c, 63d, 63e, 63f of a horn 631, 632 are each arranged on two curved surfaces which are arranged at an angle other than 180° to each other. The air cap 62 has, at its rear end, a step 62b which extends around the entire circumference of the air cap 62. A groove 62a is arranged in front of the step 62b, which also extends around the entire circumference of the air cap 62.The air nozzle ring 64 has at least one locking lug 66, preferably three locking lugs 66, on its inner circumference in a front region, which are evenly distributed around the inner circumference of the air nozzle ring 64. To assemble the air cap 62 and the air nozzle ring 64, the air cap 62 is inserted into the air nozzle ring 64 from the rear. The locking lugs 66 engage in the groove 62 in the air cap 62 and secure the air cap 62 in the air nozzle ring 64 such that the air cap 62 is rotatably mounted about the longitudinal axis 70, but at least does not fall out of the air nozzle ring 64 on its own in the axial direction. In the assembled state, the step 62b of the air cap 62 rests against a counter-surface 66b on the inner circumference of the air nozzle ring 64 and secures the air cap 62, particularly towards the front, in the air nozzle ring 64.A sealing element, particularly a sealing element made of PTFE, can be arranged between the air cap 62 and the air nozzle ring 64, in particular between the step 62b and the counter-surface 66b. The locking lugs 66 have at least one chamfer 66a, which allows the locking lugs 66 to more easily disengage from the groove 62a in the air cap 62 when the air cap 62 is pushed out of the air nozzle ring 64 for disassembly.

[0046] Reference sign

[0047] 10, 51 Compressed air valve seat unit

[0048] 11.52 cage

[0049] 12 Valve seat surface

[0050] 13, 57 Interior of the cage

[0051] 14 Outlet interface

[0052] 15 Surface area of ​​the cage

[0053] 16 first row of openings

[0054] 17 second row of openings

[0055] 18 Longitudinal direction

[0056] 19, 20, 22, 32 openings

[0057] 21 Circumferential direction

[0058] 23 third row of openings

[0059] 24 bore

[0060] Phases 25, 26, and 27

[0061] 28 inner diameter openings

[0062] 29 Inner diameter cage

[0063] 30 Passage opening

[0064] 31 Nut

[0065] 33 external threads

[0066] 50 paint gun

[0067] 53 Compressed air supply channel

[0068] 54 Wide-beam / omni-beam control unit

[0069] 55 air pistons

[0070] 56 Valve seat surface

[0071] 58 paint gun bodies

[0072] 59 Seal

[0073] 60 air nozzle arrangement

[0074] 62 air cap

[0075] 62a Nut

[0076] Level 62b

[0077] 63a, 63b, 63c, 63d, 63e, 63f horn opening

[0078] 631, 632 Horn

[0079] 64 Air jet ring

[0080] 65 central opening

[0081] 66 Rastnase

[0082] 66a Slope

[0083] 66b Counter-surface

[0084] 70 Longitudinal axis

Claims

Claims 1. Compressed air valve seat unit (10, 51) for a paint gun (50), comprising: a cage (11, 52); wherein the cage (11, 52) is arranged within a paint gun body (58) between a compressed air supply channel (53) and a wide-jet / round-jet control unit (54) to be arranged; wherein the cage (11, 52) is configured to receive an air piston (55); wherein the cage (11, 52) has a valve seat surface (12); wherein the valve seat surface (12) is configured to be brought into contact with a valve seat counter surface (56) of the air piston (55) in a first position of the air piston (55) in such a way as to prevent a flow of compressed air; wherein the valve seat surface (12) is configured to be brought into contact with a valve seat counter surface (56) of the air piston (55) in a second position of the air piston (55) being spaced apart from the valve seat counter surface (56) of the air piston (55) so that the compressed air flow flows into an interior region (13, 57) of the cage (11, 52); wherein the cage (11, 52) has an outlet interface (14) for the compressed air flow from the interior region (13, 57) of the cage (11, 52) into the wide-spray / round-spray control unit (54); wherein the outlet interface (14) is arranged over an entire circumference of a lateral surface (15) of the cage (11, 52) so that the cage (11, 52) can be arranged in any orientation within the paint gun body (58); wherein the outlet interface (14) has at least a first row of openings (16) distributed over the circumference of the lateral surface (15) and a second row of openings (17) distributed over the circumference of the lateral surface (15).

2. Compressed air valve seat unit (10, 51) according to claim 1, wherein the first row of openings (16) is arranged offset in the longitudinal direction (18) to the second row of openings (17).

3. Compressed air valve seat unit (10, 51) according to claim 1 or 2, wherein the openings (19) of the first row of openings (16) are arranged offset in the circumferential direction (21) to the openings (20, 22) of the second row of openings (17).

4. Compressed air valve seat unit (10, 51) according to claim 3, wherein an opening (19) of the openings of the first row of openings (16) is arranged in the circumferential direction (21) centrally between two openings (20, 22) of the openings of the second row of openings (17).

5. Compressed air valve seat unit (10, 51) according to one of the preceding claims, wherein the outlet interface (14) has a third row of openings (23).

6. Compressed air valve seat unit (10, 51) according to one of the preceding claims, wherein the opening (19, 20, 22, 32) each has a bore (24).

7. Compressed air valve seat assembly (10, 51) according to one of the preceding claims, wherein the opening (19, 20, 22, 32) has a chamfer (25, 26, 27).

8. Compressed air valve seat unit (10, 51) according to one of the preceding claims, wherein the chamfer (26) of the opening (20, 22) in the second row of openings (17) is larger than the chamfer (25, 27) of the opening (19, 32) in the first row of openings (16) and the third row of openings (23).

9. Compressed air valve seat unit (10, 51) according to one of the preceding claims, wherein the openings (19, 20, 22, 32) have a substantially identical cross-sectional area.

10. Compressed air valve seat unit (10, 51) according to one of the preceding claims, wherein the ratio between a cross-sectional area of ​​an opening (19, 20, 22, 32) and a cross-sectional area of ​​the interior (13, 57) of the cage (11, 52) in the region of the openings (19, 20, 22, 32) is between 0.04 and 0.

06.

11. Compressed air valve seat unit (10, 51) according to one of the preceding claims, wherein the cage (11, 52) is one-piece and / or wherein the cage (11, 52) comprises a plastic as a material.

12. Compressed air valve seat unit (10, 51) according to one of the preceding claims, wherein the cage (11, 52) has a through-opening (30) for receiving and guiding the air piston (55) and / or wherein the cage (11, 52) has a groove (31) for receiving a seal (59) for sealing the cage (11, 52) against the paint gun body (58).

13. Paint gun (50) comprising a paint gun body (58), an air piston (55), a wide-jet / round-jet control unit (54), and a compressed air valve seat unit (10, 51) according to one of claims 1 to 12.

14. Paint gun (50) according to claim 13, characterized in that it has a air nozzle arrangement (60) comprising in particular an air cap (62) and a air nozzle ring (64) comprising, wherein the air nozzle ring (64) has at least one locking lug (66), in particular three locking lugs (66), which is designed to engage in a groove (62a) in the air cap (62), wherein the locking lug (66) has at least one inclined surface (66a).

15. Paint gun (50) according to one of claims 13 or 14, characterized in that it has an air nozzle ring (64) with at least two locking lugs (66) arranged not opposite each other, in particular at least two locking lugs (66) arranged not diametrically opposite each other, wherein the air nozzle ring (64) in particular has an odd number of locking lugs (66) which are arranged evenly distributed over the inner circumference of the air nozzle ring (64).

16. Paint gun (50) according to one of claims 13 to 15, characterized in that it has an air nozzle ring (64) with at least one locking lug (66) which is spaced from the front end of the air nozzle ring (64) in an axial direction, in particular in the direction of a longitudinal axis (70).

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