Paint pistol

Abstract

The invention relates to a paint pistol (100) comprising: a paint pistol body (110) with a first compressed air interface (120); an air micrometer (20) for regulating the compressed air, comprising a second compressed air interface (21) which corresponds to the first compressed air interface (120); and a rotary joint (22) with an interface (23) for a compressed air hose (143), wherein the rotary joint (22) is designed to provide a rotational movement between the air micrometer (20) and the interface (23) for the compressed air hose (143), the rotary joint (22) has an inner body (24) and an outer body (25) which are designed to rotate relative to each other, and the inner body (24) or the outer body (25) of the rotary joint (22) and at least one part of the air micrometer (20) are integrally formed.

Description

[0001] paint spray gun

[0002] The invention relates to a paint spray gun, a use of an air micrometer, and an air micrometer, each having good handling and efficient operation.

[0003] Paint spray guns are generally well-known in the art and are used, for example, in automotive workshops for painting cars. Paint spray guns are used to atomize flowable material and apply it to a surface. The material to be applied can be either liquid or powder. The paint spray gun has a compressed air interface and usually an air micrometer for regulating the compressed air supply. For easier handling, the paint spray gun usually has a swivel joint between the compressed air hose and the paint spray gun.

[0004] In this context, it has now become apparent that there is a further need to provide a paint spray gun, in particular there is a need to provide a paint spray gun with good handling and efficient operation.

[0005] These and other objects, which will be mentioned upon reading the following description or which may be recognized by a person skilled in the art, are achieved 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, a paint spray gun is provided, comprising: a paint spray gun body with a first compressed air interface, an air micrometer for regulating compressed air with a second compressed air interface corresponding to the first compressed air interface, a rotary joint with an interface for a compressed air hose, wherein the rotary joint is configured to provide a rotary movement between the air micrometer and the interface for the compressed air hose, wherein the rotary joint has an inner body and an outer body which are configured to rotate relative to one another, wherein the inner body or the outer body of the rotary joint and at least a part of the air micrometer are integrally formed.

[0007] According to a further aspect, an air micrometer for regulating compressed air for a paint spray gun is provided, comprising a rotary joint with an interface for a compressed air hose, wherein the rotary joint is configured to provide a rotary movement between the air micrometer and the interface for the compressed air hose, wherein the rotary joint has an inner body and an outer body which are configured to rotate relative to one another, wherein the inner body or the outer body of the rotary joint and at least a part of the air micrometer are integrally formed.

[0008] The following statements apply to both the paint spray gun according to the invention and the air micrometer according to the invention. In particular, the air micrometer according to the invention can be used in a paint spray gun according to the invention.

[0009] The term "paint spray gun" refers in particular to a hand-held paint application unit with a trigger handle for actuating a valve designed to release a paint stream. The terms "paint gun", "paint nozzle" or other designations containing the terms "paint" or "color" are not to be understood as restricting these materials. The paint gun according to the invention can be used to spray, for example, paint, adhesive or varnish, in particular base and clear coat, both solvent-based and water-based, as well as liquids for the food industry, wood preservatives or other liquids. The said paint gun can be a hand-held paint gun, but also an automatic or robotic gun. Hand-held paint guns are primarily used by craftsmen, in particular painters, carpenters and varnishers.Automatic and robot guns are generally used in conjunction with a painting robot or a painting machine for industrial applications. However, it is also conceivable to integrate a manual spray gun into a painting robot or a painting machine. In particular, a paint gun according to the invention designed as a hand-held paint gun can be designed as a gravity-feed gun with a paint cup arranged above the paint gun body, from which the material to be sprayed flows into and through the paint channels essentially by gravity and by vacuum at the front end of the paint nozzle. However, the paint gun according to the invention can also be a side-feed gun, in which the paint cup is arranged on the side of the paint gun body, and in which the material is also fed to the gun by gravity and by vacuum at the front end of the material nozzle.However, the paint spray gun according to the invention can also be designed as a suction or suspended cup gun with a paint cup arranged below the paint gun body, from which the material to be sprayed is sucked out of the cup essentially by vacuum. Furthermore, it can be designed as a pressure cup gun, in which the cup is arranged below, above, or to the side of the paint gun body and is pressurized, whereupon the material to be sprayed is forced out of the cup. Furthermore, it can be a pressure-feed gun, in which the material to be sprayed is fed to the spray gun via a hose from a paint container or via a pump. The paint spray gun according to the invention can be a low-pressure gun, in particular an HVLP gun, with an internal nozzle pressure of a maximum of 10 psi or 0.7 bar, whereby transfer rates of more than 65% can be achieved.However, it could also be a compliant gun, which has an internal nozzle pressure of more than 10 psi or 0.7 bar, but also achieves a transfer rate of more than 65%. It could be an air-atomizing spray gun. It could be an air-assisted spray gun. It could also be a different type of spray gun.

[0010] The paint spray gun may include a compressed air connection, a paint needle, a trigger for opening an air valve and / or for moving the paint needle out of the paint nozzle outlet, a round-to-wide jet regulator for adjusting the ratio of atomizing air to horn air to shape the paint jet, a material flow regulator for adjusting the maximum material flow rate, a material connection, paint channels for directing the material to be sprayed from a material inlet to the material outlet, a suspension hook, and / or an analog or digital pressure gauge. However, it may also include other components from the prior art.

[0011] The term "paint spray gun body" refers in particular to a housing designed to arrange the components of a paint spray gun relative to one another and to at least partially enclose them. The paint spray gun body in particular has a handle. In or on the paint spray gun body in particular a needle valve for applying paint and, if applicable, an air valve for releasing compressed air, a compressed air interface and a paint connection are arranged. Furthermore, in particular a paint nozzle body is arranged on the paint spray gun body. The paint spray gun body in particular has an interface for the paint nozzle body and the paint nozzle body has a corresponding interface. The interfaces are in particular designed as threads. The paint spray gun body can be made of plastic or metal.

[0012] The term "compressed air interface" refers in particular to an interface through which compressed air can be transported from one structural unit to another structural unit. The compressed air interface can comprise a sealing ring and / or a mechanical coupling element. The compressed air interface connects, in particular, two flow channels for transporting compressed air from one flow channel to the second flow channel.

[0013] The term "air micrometer" refers in particular to a device for regulating an air flow. In this case, the air micrometer means a single-axis air micrometer. The air micrometer comprises, for example, a hollow body with a web and outlet holes on both sides of the web. The air flow between the outlet holes on both sides of the web can be influenced via an externally arranged, movable sleeve. For example, the air micrometer can assume different positions, such as open, partially open, or closed. The air micrometer can be used, in particular, to regulate air pressure and / or air volume flow. The air micrometer can be used, in particular, to regulate the flow cross-section for the air flowing into the paint spray gun, in particular to increase and / or decrease it.By means of the air micrometer, the flow cross-section for the air flowing into the upper area of ​​the base body of the spray gun can be regulated, in particular increased and / or reduced.

[0014] The term "swivel joint" refers specifically to a joint that enables rotary movement between the air micrometer and the interface for the compressed air hose connection. The swivel joint can be constructed in several parts. The swivel joint can include a plain bearing and / or a rolling bearing.

[0015] The term “integral” means in particular made in one piece, especially in one piece.

[0016] The present invention is based on the finding that paint spray guns have a swivel joint for improved handling. If the paint spray gun is operated with a standard hose connection without a swivel joint, the swiveling of the paint spray gun to the left and right creates torsion in the hose attached to the paint spray gun. The user of the paint spray gun must work against the resulting force, which is tiring.

[0017] The swivel joint allows the spray gun to be pivoted left and right more freely relative to the hose. The swivel joint is usually connected to the spray gun body on the one hand and to the hose on the other. Furthermore, spray guns are known in the art that have a swivel joint and an air micrometer on the underside of the spray gun body. The air micrometer and swivel joint are designed separately, i.e., in different locations and / or are not integral. If the air micrometer and swivel joint were arranged one behind the other, the connection would, for structural reasons, reduce the diameter of the flow channel in the air micrometer. This acts like an orifice and leads to a loss of pressure or energy.The invention solves this problem by designing at least part of the swivel joint, specifically the inner body or outer body of the swivel joint, and at least part of the air micrometer, specifically the inner body of the air micrometer, as an integral or one-piece construction. This eliminates cross-sectional tapering and, while maintaining consistent mobility, prevents pressure loss. In particular, the locking function (i.e., axial bearing) and the rotary bearing are combined, so that no reduction in the cross-section of the flow channel occurs. This enables efficient operation of the spray gun according to the invention.

[0018] According to one embodiment, at least one intermediate body is arranged between the inner body and the outer body of the rotary joint to provide the rotary movement. The inner body can comprise rolling elements or sliding elements.

[0019] In this way, the smoothness of the rotational movement can be increased.

[0020] According to one embodiment, the at least one intermediate body is a rolling element. The rolling element can be spherical or roller-shaped.

[0021] This reduces friction during rotation, increasing the smoothness of the rotation. With rolling elements, smoothness and rotational behavior are less dependent on the pressure within the air micrometer. Thus, rolling elements improve the usability of the spray gun.

[0022] In one embodiment, the at least one intermediate body is a sliding body. The sliding body is, for example, a sleeve made of a plastic material that is arranged between the inner body and the outer body.

[0023] This allows for increased smoothness of the rotary motion. The sliding elements can be smaller than rolling elements, resulting in a more compact design.

[0024] In one embodiment, the outer body has an undercut for axially supporting the outer body on the inner body, wherein the undercut is configured to engage behind the intermediate body. The undercut is designed, for example, as a semi-open channel, for example, to engage around a corresponding ball. The undercut can be designed as a shoulder, for example, to engage around a corresponding sleeve.

[0025] This allows for axial support of the outer body on the inner body, allowing for a combination of rotary and axial bearings.

[0026] In one embodiment, the intermediate body is mounted or fixed in the axial direction on the inner body. For example, the inner body has an undercut in the form of a semi-open channel for the intermediate body, which supports the intermediate body in the axial direction. Alternatively, the intermediate body can also be mounted by at least one shoulder arranged circumferentially on the inner body's lateral surface. Alternatively, the intermediate body, e.g., a plastic sleeve, can also be axially fixed to the inner body via a press fit.

[0027] In this way, axial support of the outer body on the inner body can be made possible.

[0028] In one embodiment, a diameter of a flow channel of the rotary joint is greater than or equal to a diameter of a flow channel of the air micrometer.

[0029] Due to the integral design of the inner body or the outer body of the rotary joint and the adjoining inner body of the air micrometer, the diameter of the flow channel of the rotary joint can be larger than the diameter of the flow channel of the air micrometer, or the diameter of the flow channel of the rotary joint can be the same as the diameter of a flow channel of the air micrometer. With conventional separate rotary joints, the diameter of the flow channel of the rotary joint would be smaller than the diameter of the flow channel of the air micrometer. This would lead to pressure losses. Particularly preferably, the inner body of the rotary joint and part of the air micrometer are designed as an integral part. This component can be essentially tubular with a constant inner diameter, which makes it easy to manufacture. Alternatively, the outer body of the rotary joint and part of the air micrometer can be designed as an integral part.This component can be widened at its end facing the interface for a compressed air hose to accommodate the inner part of the swivel joint, which then has the interface for the compressed air hose, in particular a hose connection. This also allows a constant inner diameter between the swivel joint and the air micrometer to be achieved without any cross-sectional tapering.

[0030] In this way, there are no or significantly lower flow losses or pressure losses through the swivel joint.

[0031] In one embodiment, the interface for the compressed air hose of the swivel joint has a threaded connection, wherein the thread is in particular a 1 / 4 inch thread. This allows a standard compressed air hose to be connected to the swivel joint via a standardized interface, the 1 / 4 inch threaded interface. For example, a quick-release coupling can be provided. This has a positive effect on the usability of the paint spray gun.

[0032] In one embodiment, a sealing ring is arranged between the inner body and the outer body, wherein the sealing ring contains polyfluorinated hydrogen or polytetrafluoroethylene. The sealing ring consists, for example, of at least 90% (by weight) of polytetrafluoroethylene.

[0033] In this way, the swivel joint is sealed against the environment with low friction, so that the loss of compressed air is low, but the rotational movement is only slightly inhibited.

[0034] In one embodiment, the air micrometer and the first compressed air connection are arranged on one axis. The air micrometer is arranged, for example, in the area of ​​the handle of the gun body. The corresponding interface for the compressed air hose is arranged, for example, below the air micrometer. The geometry of the swivel joint described above means that the swivel joint is also arranged on one axis to the air micrometer. The air micrometer is designed as a single-axis air micrometer. Two-axis air micrometers often have an axially movable piston and are arranged, for example, in a bore in the handle of the gun body next to the air inlet bore, with the bore for the two-axis air micrometer being aligned at an angle to the air inlet bore. The bore for the two-axis air micrometer converges with the air inlet bore in an upper area.The piston of the dual-axis air micrometer can be moved from the bore in which it is located, successively into the air inlet bore, or moved back out of the air inlet bore, to successively reduce or increase the flow cross-section of the air inlet bore. This allows the air flowing into the upper area of ​​the gun body to be regulated. In particular, air pressure and / or volume flow can be regulated.

[0035] The advantage of the single-axis air micrometer over the dual-axis air micrometer is that no additional drilling is required for the dual-axis air micrometer, as it can be installed in the existing air inlet hole in the handle of the gun body.

[0036] In one embodiment, the air micrometer is located below the gun body.

[0037] In this way, the air micrometer is easily accessible and operable during operation. In one embodiment, the air micrometer comprises an inner body and a sleeve surrounding the inner body, wherein the inner body of the air micrometer and the inner body or the outer body of the rotary joint are integrally formed.

[0038] In this way, the rotary joint and the air micrometer can be designed more compactly than if they were designed separately. Furthermore, the diameter of the flow channel of the inner body of the rotary joint can be the same as the diameter of the flow channel of the inner body of the air micrometer or larger than the diameter of the flow channel of the air micrometer. This reduces flow losses.

[0039] Another aspect of the present invention relates to the use of an air micrometer in a paint spray gun as described in more detail above.

[0040] The features described above, including those from different embodiments, can also be combined with each other, resulting in synergistic interactions that go beyond the sum of the individual effects.

[0041] The invention is explained below using exemplary embodiments, which are described with reference to the following figures:

[0042] Figure 1 shows an exemplary embodiment of an air micrometer according to the invention or an air micrometer with a swivel joint according to an exemplary embodiment of a paint spray gun according to the invention; and

[0043] Figure 2 shows an exemplary paint spray gun according to the invention.

[0044] Exemplary embodiments are described and explained below with reference to the figures listed above. Like reference symbols or analogous reference symbol structures refer to analogous or interacting components.

[0045] Figure 1 shows an air micrometer 20 with a swivel joint 22 according to an exemplary embodiment of a paint spray gun 100 according to the invention (not shown in Fig. 1). The swivel joint 22 enables a rotary movement between the air micrometer 20 and an interface 23 for a compressed air hose 143 (not shown in Fig. 1), which is arranged on the swivel joint 22. The air micrometer 20 has a second compressed air interface 21, which is designed to be connected to the first corresponding compressed air interface 120 (not shown in Fig. 1) of the paint spray gun body 110. In the area of ​​the second compressed air interface 21, a thread 37 for mounting a stop ring 38 on the air micrometer 20 is arranged. The stop ring 38 is screwed onto a horseshoe ring 36 via the thread 37. The stop ring 38 is used to mount the air micrometer 20 within the spray gun body 110.The air micrometer 20 is coupled to the paint gun body 110 via the thread 37. The air micrometer 20 has an inner body 32. The inner body 32 has a flow channel 31 with a diameter of 30. The air micrometer 20 also has a sleeve 33 surrounding the inner body 32. The inner body 32 and sleeve 33 are connected to one another via a thread 34 such that rotation of the sleeve 33 about the longitudinal axis of the air micrometer 20 generates a movement of the sleeve 33 in the longitudinal direction of the air micrometer 20. In this way, the sleeve 33 is displaced along the inner body 32. By displacing the sleeve 33, the compressed air flow can be regulated, which flows from the flow channel 31 into a second flow channel 42 downstream. The swivel joint 22 has an inner body 24 and an outer body 25.The inner body 24 of the rotary joint 22 and the inner body 32 of the air micrometer 20 are integrally constructed in one piece. In this case, the rotary joint 22 further has an interface 23 for a compressed air hose 143. The interface 23 in this case has a threaded connection 39. The threaded connection 39 is, for example, 1 / 4 inch in size. Rolling balls are arranged as intermediate bodies 26 between the outer body 25 and the inner body 24 of the rotary joint 22. The outer body 25 has an undercut 27 designed to enable axial mounting of the outer body 25 in the longitudinal direction of the rotary joint 22. The inner body 24 has a channel 40 for guiding the rolling elements 26. The inner body 24 of the rotary joint 22 and the outer body 25 of the rotary joint 22 are sealed against one another with a sealing ring 43. The sleeve 33 is sealed against the inner body 32 of the air micrometer 20 with a sealing ring 35.The sealing ring 41 seals the sleeve 33 against the interior (not shown) of the spray gun body. The diameter 28 of the flow channel 29 of the swivel joint 22 and the diameter 30 of the flow channel 31 of the air micrometer 20 are the same size in this case.

[0046] Figure 2 shows an exemplary paint spray gun 100 according to the invention. The paint spray gun 100 comprises a paint spray gun body 110. The paint spray gun body 110 is made of metal in the present case, but can also be made of plastic, and has a handle. In the present case, a needle valve for applying paint and, if appropriate, an air valve for releasing compressed air, a first compressed air interface 120, and a paint connection are arranged in the paint spray gun body 110. The paint spray gun 100 further comprises a paint nozzle body 150, which is detachably connected to the paint spray gun body 110 via a thread, but is not visible in Figure 2 because it is covered by the air cap and the air nozzle ring. The paint spray gun 100 further comprises an actuating bracket element 130. The actuating bracket element 130 is designed to be detachably connected to the paint spray gun body 110.For example, this detachable connection can be made possible via a plug-in or snap-in connection. The actuating bracket element 130 is rotatably mounted via a bolt in a bore in the paint gun body 110. By actuating the actuating bracket element 130, the needle valve for applying paint and the air valve for releasing compressed air are actuated. The second corresponding compressed air interface 21 of the air micrometer 140 is coupled to the first compressed air interface 120 in the paint gun body 110. The air micrometer 140 with the integrally formed swivel joint 141 corresponds to the air micrometer 20 described in Figure 1. A compressed air hose 143 is connected to the interface 142 for the compressed air hose 143.

[0047] Reference symbol

[0048] 20 air micrometers

[0049] 21 second compressed air interface

[0050] 22 Swivel joint

[0051] 23 Interface for compressed air hose connection

[0052] 24 inner bodies

[0053] 25 outer bodies

[0054] 26 intermediate bodies

[0055] 27 Undercut

[0056] 28 diameter flow channel swivel joint

[0057] 29 Flow channel swivel joint

[0058] 30 diameter flow channel micrometers

[0059] 31 Flow channel micrometer

[0060] 32 inner body air micrometer

[0061] 33 Sleeve air micrometer

[0062] 34 threads

[0063] 35 Sealing ring

[0064] 36 horseshoe ring for stop ring

[0065] 37 threads

[0066] 38 stop ring

[0067] 39 threaded connection

[0068] 40 channel rolling bearings

[0069] 41 Sealing ring

[0070] 42 second flow channel micrometer

[0071] 43 Sealing ring

[0072] 100 paint spray gun

[0073] 110 spray gun body

[0074] 120 first compressed air interface spray gun body

[0075] 130 Actuating bracket element

[0076] 140 air micrometers

[0077] 141 Swivel joint

[0078] 142 Interface for compressed air hose connection

[0079] 143 compressed air hose

[0080] 150 paint nozzle bodies

Claims

Claims 1. Paint spray gun (100), comprising: Paint spray gun body (110) with a first compressed air interface (120); air micrometer (20) for regulating compressed air with a second compressed air interface (21) corresponding to the first compressed air interface (120); swivel joint (22) with an interface (23) for a compressed air hose (143); wherein the swivel joint (22) is configured to provide a rotational movement between the air micrometer (20) and the interface (23) for the compressed air hose (143); wherein the swivel joint (22) has an inner body (24) and an outer body (25) which are configured to rotate relative to one another; wherein the inner body (24) or the outer body (25) of the swivel joint (22) and at least a part of the air micrometer (20) are integrally formed.

2. Paint spray gun (100) according to claim 1, wherein at least one intermediate body (26) for providing the rotary movement is arranged between the inner body (24) and the outer body (25).

3. Paint spray gun (100) according to claim 2, wherein the at least one intermediate body (26) is a rolling body (26).

4. Paint spray gun (100) according to claim 2, wherein the at least one intermediate body (26) is a sliding body.

5. Paint spray gun (100) according to one of claims 2 to 4, wherein the outer body (25) has an undercut (27) for axially mounting the outer body (25) on the inner body (24) and wherein the undercut (27) is designed to engage behind the intermediate body (26).

6. Paint spray gun (100) according to claim 5, wherein the intermediate body (26) is mounted or fixed in the axial direction on the inner body (24).

7. Paint spray gun (100) according to one of the preceding claims, wherein a diameter (28) of a flow channel (29) of the rotary joint (22) is greater than or equal to a diameter (30) of a flow channel (31) of the air micrometer (20).

8. Paint spray gun (100) according to one of the preceding claims, wherein the interface (23) for the compressed air connection of the swivel joint (22) comprises a threaded connection (39), wherein the thread is in particular a % inch thread.

9. Paint spray gun (100) according to one of the preceding claims, wherein a sealing ring (43) is arranged between the inner body (24) and the outer body (25), the sealing ring (43) containing polytetrafluoroethylene.

10. Paint spray gun (100) according to one of the preceding claims, wherein the air micrometer (20) and the first compressed air interface (120) are arranged in one axis.

11. Paint spray gun (100) according to one of the preceding claims, wherein the air micrometer (20) is arranged below the paint spray gun body (110).

12. Paint spray gun (100) according to one of the preceding claims, wherein the air micrometer (20) comprises an inner body (32) and a sleeve (33) surrounding the inner body (32), wherein the inner body (32) or the outer body (25) of the air micrometer (20) and the inner body (24) of the swivel joint (22) are integrally formed.

13. Use of an air micrometer (20) with a swivel joint (22) in a paint spray gun (100) according to one of claims 1 to 12.

14. An air micrometer (20) for regulating compressed air for a paint spray gun (100), comprising a rotary joint (22) with an interface (23) for a compressed air hose (143); wherein the rotary joint (22) is configured to provide a rotary movement between the air micrometer (20) and the interface (23) for the compressed air hose (143); wherein the rotary joint (22) has an inner body (24) and an outer body (25) which are configured to rotate relative to one another; wherein the inner body (24) or the outer body (25) of the rotary joint (22) and at least a part of the air micrometer (20) are integrally formed.

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