SPRAY GUN, PRESSURE MEASURING DEVICE FOR A SPRAY GUN AND METHOD FOR DEVELOPING A SPRAY GUN

Abstract

A spray gun, in particular a pressurised air atomisation paint spray gun, in particular a hand-held pressurised air atomisation paint spray gun has at least one material nozzle for discharging a material to be sprayed, at least one air nozzle for outputting air, in particular air for atomising a material to be sprayed, air for changing the shape of a spray jet, and/or air for transporting an atomised spraying medium, and at least one air chamber, in particular an air chamber adjoining the air nozzle or at least one air outlet opening of the air nozzle in the upstream direction, for supplying the air nozzle with air. The spray gun also has at least one device for inputting and/or adjusting and/or detecting and/or determining and/or displaying the air pressure in the air chamber during operation of the spray gun.

Claims

1-17. (canceled)

18. A spray gun having at least one material nozzle for delivering a material to be sprayed, at least one air nozzle for delivering air, at least one air chamber which upstream is adjacent to the at least one air nozzle or to at least one air outlet opening of the at least one air nozzle, for supplying the at least one air nozzle with air, and at least one device for entering and/or adjusting and/or detecting and/or determining and/or displaying air pressure prevalent in the at least one air chamber during operation of the spray gun.

19. The spray gun of claim 18, wherein the spray gun further comprises an air cap having a central opening, wherein the central opening conjointly with a front region of the at least one material nozzle forms an annular gap for delivering air for atomizing a material to be sprayed, and wherein at least one air chamber is formed by the at least one material nozzle and the air cap.

20. The spray gun of claim 18, wherein at least one device for detecting an air pressure which wirelessly and/or by wire is connected and/or connectable to a device for controlling and/or feedback-controlling an air pressure and/or to a device for displaying an air pressure and/or to a data processing device is disposed in the at least one air chamber on an internal face of the air cap and/or on an external face of the at least one material nozzle.

21. The spray gun of claim 18, wherein the spray gun further comprises: at least one air duct for directing air from an air inlet to an air outlet, at least one device for detecting an air pressure which is disposed outside the at least one air chamber, and a device for determining the air pressure prevalent in the at least one air chamber during operation of the spray gun based on the air pressure value determined by the device for detecting an air pressure.

22. The spray gun of claim 18, wherein the spray gun has at least one device for determining the air pressure prevalent in the at least one air chamber during operation of the spray gun and at least one replaceable component including a replaceable material nozzle and/or a replaceable air nozzle, wherein the device for determining the air pressure prevalent in the at least one air chamber during operation of the spray gun is designed such that the determination of the air pressure prevalent in the at least one air chamber during operation of the spray gun is determined as a function of at least one parameter of the replaceable component and/or of at least one dimension of the replaceable component.

23. The spray gun of claim 18, wherein the spray gun has at least one replaceable component including at least one of a replaceable nozzle assembly, a replaceable material nozzle and/or a replaceable air nozzle, and at least one device for detecting an item of information pertaining to a type and/or to a dimension of the component disposed in the spray gun and/or is wirelessly and/or by wire connected and/or connectable to a device of this type.

24. The spray gun of claim 18, wherein the spray gun has at least one device for feedback-controlling and/or delimiting the air pressure prevalent in the at least one air chamber during operation of the spray gun and/or is wirelessly and/or by wire connected and/or connectable to a device of this type.

25. The spray gun of claim 18, wherein the spray gun has at least one device for entering a target value and/or a minimum value and/or a maximum value for the air pressure prevalent in the air chamber during operation of the spray gun and/or is wirelessly and/or by wire connected and/or connectable to a device of this type.

26. The spray gun of claim 18, wherein the spray gun has at least one device for emitting a signal which is connected and/or connectable to a device for determining the air pressure prevalent in the at least one air chamber during operation of the spray gun, to a device for controlling and/or feedback-controlling and/or delimiting an air pressure, to a device for displaying an air pressure and/or to a data processing device.

27. The spray gun of claim 18, wherein the spray gun has at least one nozzle assembly having at least one air nozzle having an air cap, wherein the air nozzle has at least one first outlet opening for exhausting atomization air and at least one second outlet opening for exhausting forming air, wherein at least one first device for detecting an air pressure is disposed in the region of the first outlet opening of the air nozzle, and/or wherein at least one second device for detecting an air pressure is disposed in the region of the second outlet opening of the air nozzle.

28. A pressure measuring device for a spray gun having at least one material nozzle for delivering a material to be sprayed, at least one air nozzle for delivering air, at least one air chamber for supplying the at least one air nozzle with air, at least one air duct for directing air from an air inlet to the at least one air nozzle, the pressure measuring device comprising: at least one device for detecting an air pressure, wherein the pressure measuring device is fastened or fastenable to the spray gun such that the pressure measuring device is connected to the at least one air duct, a device for determining the air pressure prevalent in the at least one air chamber during operation of the spray gun based on the air pressure value determined by the device for detecting an air pressure.

29. The pressure measuring device of claim 28, wherein the pressure measuring device has a device for detecting an item of information pertaining to a spray gun, to a type and/or a dimension of a component disposed in the spray gun and/or is wirelessly and/or by wire connected and/or connectable to the item of information detecting device.

30. The pressure measuring device of claim 28, wherein the pressure measuring device has at least one display device for displaying a pressure value.

31. The pressure measuring device of claim 28, wherein the pressure measuring device has at least one device for emitting a signal which is connected and/or connectable to a device for determining the air pressure prevalent in the air chamber during operation of the spray gun, to a device for controlling and/or feedback-controlling and/or delimiting an air pressure, to a device for displaying an air pressure and/or to a data processing device.

32. A method for designing the spray gun of claim 21, the method comprising: determining a variance between a first air pressure, which is prevalent at a first position within the spray gun during operation of the spray gun, and a second air pressure, which is prevalent at a second position within the spray gun during the operation of the spray gun, wherein the first position is situated within the air chamber, and wherein the second position is situated outside the air chamber.

33. The method of claim 32, further comprising: designing a pressure measuring device for the spray gun, wherein the pressure measuring device is designed such that the pressure measuring device takes into account the variance between the first air pressure at the first position within the spray gun and the second air pressure at the second position within the spray gun.

34. The method of claim 32, further comprising: disposing the pressure measuring device at the second position.

Description

[0071] FIG. 1 shows a perspective view of an exemplary embodiment of a spray gun according to the invention,

[0072] FIG. 2 shows a sectional view of the head region of an exemplary embodiment of a spray gun according to the invention, and

[0073] FIG. 3 shows a diagram with an example of a characteristic line which shows the air pressure within an air chamber plotted over the air pressure outside an air chamber, as well as of a characteristic line which shows the variance between the air pressure outside an air chamber and the air pressure within an air chamber plotted over the air pressure outside an air chamber.

[0074] FIG. 1 shows a perspective view of an exemplary embodiment of a spray gun 1 according to the invention, having a main body 3, an air inlet 4 being disposed on the lower end of said main body 3. The spray gun 1 furthermore has an air nozzle 5 which presently comprises an air cap 9 which by means of an air nozzle ring 11 is screwed onto the main body 3 of the spray gun 1. The air cap 9 in the exemplary embodiment shown has two horns 13a, 13b having in each case two horn air openings. Moreover, said air cap 9 possesses a central opening 15 which presently, conjointly with a material nozzle screwed into the main body 3, forms an annular gap. A plurality of control openings 17 are in each case incorporated onto two mutually opposite sides of the central opening 15 so as to be next to the central opening 15. A material quantity control which is able to be activated by way of a material quantity rotary control button 19 is disposed in the spray gun 1. A rear detent for a paint needle is able to be defined by way of the material quantity control, i.e. it can be adjusted by way of the material quantity control how far the paint needle can exit the material outlet opening of the material nozzle when the trigger 18 is activated. As a result, the maximum flow cross section for the material flowing out of the material outlet opening of the material nozzle, and thus the quantity of the material sprayed by the spray gun 1, is defined.

[0075] The spray gun 1 moreover has a device by way of which the quantity of air which, from an air inlet duct assembly which is not visible in FIG. 1 and extends upward from the air inlet 4 through the handle of the spray gun 1, flows into an upper part of the gun body 3 is able to be adjusted. To this end, a so-called air micrometer can be used, which presently is able to be activated by means of an air micrometer rotary button 21. The air micrometer can be designed as a sleeve, for example, which in the wall thereof has an opening, the degree of overlap of said opening with the port of the air inlet duct assembly being able to be adjusted. The flow cross section through which the air from the handle region of the spray gun 1 can flow into an upper part of the gun body 3 is able to be adjusted in this way.

[0076] The present exemplary embodiment of a spray gun 1 according to the invention in the interior thereof has a first air outlet duct assembly, not visible in FIG. 1, and a second air outlet duct assembly, likewise not visible in FIG. 1. The first air outlet duct assembly can in particular be an air outlet duct assembly for directing air for the atomization of a material to be sprayed. This air outlet duct assembly can be referred to as an atomization air duct assembly or as an atomization air duct. The air directed by said duct assembly or duct can flow out of the annular gap which is formed by the central opening 15 and by the material nozzle screwed into the main body 3 and said air can be referred to as atomization air. The second air outlet duct assembly can in particular be an air outlet duct assembly for directing air for changing the shape of a spray jet. This air outlet duct assembly can be referred to as a forming-air duct assembly or as a forming-air duct. The air directed by said duct assembly or duct can flow out of the forming-air openings 20 of the horns 13a, 13b and be referred to as forming air. Visible in FIG. 1 is a round-broad jet rotary button 23 for activating a control device for distributing between the atomization air duct assembly and the forming-air duct assembly the air flowing out of the air inlet duct assembly.

[0077] The spray gun 1 moreover has a device for entering and/or adjusting and/or detecting and/or determining and/or displaying the air pressure prevalent in an air chamber during the operation of the spray gun 1, said device having a display 29. In the present exemplary embodiment, this is a device for determining and displaying the air pressure prevalent in an air chamber during the operation of the spray gun, said device furthermore having a device for detecting an air pressure, in particular a pressure sensor.

[0078] The device for detecting an air pressure, in particular the pressure sensor, presently detects, in particular measures, the air pressure in a pressurized chamber close to the air valve which is able to be activated by means of the trigger 18. The device for determining the air pressure prevalent in an air chamber during the operation of the spray gun 1 determines, in particular computes, from this measured compressed air value at a position outside the air chamber that upstream is adjacent to at least one air outlet opening, the air pressure prevalent in the air chamber during the operation of the spray gun 1. This takes place by means of the above-described taking into account of a known variance and/or series of variances between the air pressure values stored in the device for determining the air pressure prevalent in the air chamber during the operation of the spray gun 1 and/or an above-described characteristic line stored in this device.

[0079] The device for displaying the air pressure prevalent in the air chamber during the operation of the spray gun by means of the display 29 preferably displays the air pressure prevalent in the air chamber during the operation of the spray gun 1.

[0080] However, the spray gun 1 can also have a device for detecting an air pressure, in particular a pressure sensor, which is disposed in the air chamber and is connected wirelessly and/or by wire to a device for controlling and/or feedback-controlling an air pressure and/or to a device for displaying an air pressure and/or to a data processing device. The device for detecting an air pressure, in particular the pressure sensor, can be disposed within the air chamber and directly detect, in particular measure, the air pressure prevalent in the air chamber during the operation of the spray gun 1, and transmit said air pressure to a device for displaying an air pressure, for example, to which the device for detecting an air pressure, in particular the pressure sensor, is preferably wirelessly connected. In this way, the air pressure prevalent in the air chamber during the operation of the spray gun 1 can be displayed by the display 29, for example.

[0081] FIG. 2 shows a sectional view of the head region of an exemplary embodiment of a spray gun according to the invention. An air nozzle 5 which presently has an air cap 9 and an air nozzle ring 11 is disposed on the head region of the main body 3. The air cap 9 has two horns 13a, 13b and a plurality of air outlet openings, specifically a central opening 15, a plurality of control openings 17, and in each case two forming-air openings 20 in the horn 13a and in the horn 13b. A material nozzle 40 which is screwed into the main body 3 of the spray gun 1 has a material outlet opening 28. The front end of the material nozzle 40, conjointly with the central opening 15, forms an annular gap for exhausting atomization air. The material nozzle 40 and the air cap 9 form a first air chamber 80. This here is one of the air chambers of which the air pressure prevalent therein is of particular interest in the present case. A first device for detecting an air pressure 42 is disposed in the air chamber 80, in the present exemplary embodiment on an internal face of the air cap 9. The first device for detecting an air pressure 42 is partially sunk into the air cap 9. However, said first device can also be incorporated in the air cap 9 in such a manner that the internal face of the air cap 9 and the external face of the device for detecting an air pressure 42 form a planar face without steps.

[0082] A second air chamber 82, the air pressure prevalent therein likewise being of interest in the present case, is designed as a bore in the horn 13a. A second device for detecting an air pressure 43 is disposed in said second air chamber 82. The horn 13b likewise has an air chamber designed as a bore, but in the present case no device for detecting an air pressure. By virtue of the symmetrical arrangement of the two horns 13a, 13b, and because the latter are supplied with air from the same forming-air duct assembly, it is usually not necessary for a device for detecting an air pressure to be disposed in both horns 13a, 13b, since the pressure in the two horns 13a, 13b is usually identical. Of course, it is however also possible for devices for detecting an air pressure to be disposed in both air chambers of the horns 13a, 13b.

[0083] During the operation of the spray gun, atomization air, which flows from an atomization air duct assembly in the main body 3 of the spray gun 1 into the first air chamber 80, flows through the annular gap formed by the front end of the material nozzle 40 having the central opening 15. As a result, the atomization air in the first air chamber 80 generates an air pressure, the value of the latter presently being of interest. If air is directed into the forming-air duct assembly in the main body 3 of the spray gun 1, in particular by way of a round-broad jet control which is able to be operated by the user of the spray gun 1 by way of a round-broad jet rotary button 21 shown in FIG. 1, this forming air flows from the forming-air duct assembly into the second air chamber 82 and from there through the forming-air openings 20. As a result, the forming air in the second air chamber 82 generates an air pressure which may likewise be of interest. The value measured by the first device for detecting an air pressure 42 and/or by the second device for detecting an air pressure 43 can be sent to a device for controlling and/or feedback-controlling an air pressure and/or to a device for displaying an air pressure and/or to a data processing device, for example. In the simplest case, the pressure value is sent to a device for displaying an air pressure, whereupon the pressure value is displayed on a display 29 shown in FIG. 1, for example.

[0084] FIG. 3 by way of example shows a first characteristic line 92 which shows the air pressure within an air chamber being plotted over the air pressure outside an air chamber. The air pressure within an air chamber has been plotted along the vertical primary axis 94; the air pressure outside an air chamber has been plotted along the horizontal axis 95. The first characteristic line 92 shows which air pressure is prevalent within an air chamber at which air pressure outside the air chamber. For example, it can be seen that at a pressure outside the air chamber of 0.5 bar, a pressure of 0.5 bar is also prevalent within the air chamber. At a pressure of 2.5 bar outside the air chamber, a pressure of only 2.3 bar is prevalent within the pressurized chamber. At a pressure of 5.0 bar outside the air chamber, a pressure of only 4.7 bar is prevalent within the pressurized chamber.

[0085] The second characteristic line 93 shows the variance between the air pressure outside an air chamber and the air pressure within an air chamber plotted over the air pressure outside an air chamber. The variance in the present case has been computed from the difference between the air pressure outside an air chamber and the air pressure within an air chamber. The variance has been plotted along the vertical secondary axis 96; the air pressure outside an air chamber has been plotted along the horizontal axis 95. It is apparent that the variance increases as the air pressure outside the air chamber increases. In reality, the variance does not increase in steps as is shown in the diagram, but a continuous increase is rather to be assumed. The stepped shape of the increase is due to the spacing between the points of measurement and due to the rounding of measured values.

[0086] In general, the components mentioned individually in the exemplary embodiments can be used in all exemplary embodiments. The explanations pertaining to the exemplary embodiments can also apply to all exemplary embodiments. The explanations pertaining to the spray gun according to the invention can also apply to the pressure measuring device according to the invention and to the method according to the invention; the explanations pertaining to the pressure measuring device according to the invention can also apply to the spray gun according to the invention and to the method according to the invention; the explanations pertaining to the method according to the invention can also apply to the spray gun according to the invention and to the pressure measuring device according to the invention.

[0087] The described exemplary embodiments describe only a limited selection of potential embodiments and thus do not represent any limitation of the present invention.