DE202020100084U1 - Digital pressure measuring unit for measuring and displaying air and / or material pressure, preferably a spray gun, as well as a spray gun with a digital pressure measuring unit - Google Patents

Abstract

Digital pressure measuring unit (10), in particular exchangeable digital pressure measuring unit (10), which is designed to measure and display an air pressure and / or a material pressure, in particular an air pressure and / or material pressure in or on a spray gun (1) for atomization and application, preferably with the aid of compressed air a coating material, in particular a lacquer, characterized in that the digital pressure measuring unit (10) is formed by a housing (13) which has a recess (14) which is closed in a fluid-tight manner by a pressure transmission membrane (16) to which inside of the housing (13) is bounded by a pressure measuring chamber (17).

Description

The invention relates to a digital pressure measuring unit, in particular an exchangeable digital pressure measuring unit, which is designed to measure and display an air pressure and / or a material pressure, in particular an air pressure and / or a material pressure in or on a spray gun for, preferably compressed air-assisted, atomization and application of a coating material, especially a lacquer.

The invention also relates to a spray gun with such a digital pressure measuring unit.

A digital pressure measuring unit mentioned at the beginning is, for example, from EP 3 421 140 A1 known. The digital pressure measuring unit described there forms part of the handle of a spray gun or paint spray gun. In the case of a first exemplary embodiment, a compressed air channel extends within the exchangeable pressure measuring unit, which, when the pressure measuring unit on the paint spray gun is operational, leads from a gun-side air supply channel to a transducer arranged in the pressure measuring unit, which in turn is connected to a display in the pressure measuring unit. In another exemplary embodiment, a pressure measuring sensor is arranged outside the removable pressure measuring unit and connected to the display in the pressure measuring unit via external electrical contact means.

Both exemplary embodiments have in common that they are only resistant to the contamination and impairments that occur during operation of a paint spray gun to a limited extent. Even very carefully working painters cannot avoid that a paint spray gun is contaminated at least occasionally in the area of its handle (and thus in the area of the pressure measuring unit). The cleaning agents for removing dirt or the dirt itself sometimes contain a considerable amount of solvents or other aggressive substances. If these substances act repeatedly or for a longer period of time on seals or (after failure of the seals) also directly on electronic components, there is a high risk that the components can be damaged, which can possibly render the entire system unusable or lead to a complete loss of functionality can.

In the previously known pressure measuring unit according to the first exemplary embodiment from FIG EP 3 421 140 A1 There is a particular risk of this, as solvent can accumulate in the pressure measuring channel running inside the pressure measuring unit, which cannot be easily removed and consequently can act on inner seals and components of the pressure measuring unit, such as the transducer, for a longer period of time. In the case of the second exemplary embodiment, the external electrical contact means to which the pressure measuring sensor arranged outside the pressure measuring unit is connected are largely unprotected and exposed to aggressive contamination or cleaning substances. In general, elastic seals do not offer 100% diffusion protection against organic compounds such as acetone or other organic solvents.

The present invention has set itself the task of improving the resistance of a digital pressure measuring unit for paint spray guns to soiling, cleaning agents and solvents.

The object is achieved by a digital pressure measuring unit with the features of claim 1.

The digital pressure measuring unit according to the invention is characterized in that it is formed by a housing which has a recess which is closed fluid-tight (liquid-tight and gas-tight) by a pressure transmission membrane, which is adjoined by a pressure measuring chamber which is arranged inside the housing .

Thanks to the structure according to the invention, there is no need for an internal fluid channel which is open to the outside and which can fill with impurities which - if at all - can only be removed again with difficulty. In addition, it is avoided to arrange sensitive electronic components, which are involved in the pressure measurement, unprotected on the outside of the housing of the pressure measurement unit.

The pressure transmission membrane itself is preferably designed to be very resistant and robust. In particular, it can be made of a diffusion-tight and / or solvent-resistant material, such as stainless steel. The external pressure transmission membrane can easily be freed of soiling, for example by washing it off and then wiping it off, so that long-term, flawless functionality can be guaranteed.

It is preferably an exchangeable digital pressure measuring unit. This has the advantage that the pressure measuring unit can be removed before the spray gun is treated intensively with cleaning agent, etc. Furthermore, the pressure measuring unit can be replaced very easily if its functionality should be impaired despite the increased resistance.

In a preferred embodiment, the pressure transmission membrane is surrounded on the outside of the housing by a connection seal. In this way, the pressure transmission membrane is protected from contamination and other impairments during operation by the seal. The connection seal is preferably exchangeable.

A preferred exemplary embodiment is characterized in that the pressure transmission membrane is connected to the housing in a form-fitting, force-fitting and / or material fit, preferably by means of a welded and / or adhesive connection. In particular, the connection technology is chosen so that a permanent and tight connection results in the paint environment.

A preferred exemplary embodiment in which the pressure transmission membrane is connected to the outside of the housing is advantageous in terms of manufacture.

In a particularly preferred exemplary embodiment, the housing has a recess which is closed in a fluid-tight manner by a cover plate.

Preferably, the cover plate is positively, non-positively and / or cohesively connected to the housing, preferably by means of a welded connection, an adhesive connection and / or by means of a latching frame.

In the case of a preferred exemplary embodiment, the cover plate again has the recess closed with the pressure transmission membrane. Alternatively, the recess closed with the cover plate can also be arranged on a side of the housing which differs from the side which is provided with the recess closed by the pressure transmission membrane. For example, the recesses can be arranged on the opposite side of the housing.

The cover plate is preferably at least partially transparent, so that display electronics arranged within the housing, preferably a display, are visible through the cover plate.

Handling advantages result from the fact that the cover plate is provided with a touch field.

In a particularly preferred embodiment, an energy store, preferably a rechargeable energy store, further preferably a contactlessly rechargeable energy store, for example in the form of a double-layer capacitor, is provided for supplying energy to the digital pressure measuring unit inside or inside the housing. The result is a digital pressure measuring unit that is hermetically sealed to the outside. In comparison to conventional digital pressure measuring units, it is no longer necessary to change the battery. Seals for closing an openable battery compartment can be omitted. The risk of damage due to handling errors when changing the battery is eliminated.

A pressure measuring sensor is preferably provided in the pressure measuring chamber, which is connected to evaluation electronics arranged in the interior of the housing. A compact, integral design results from the fact that the pressure measuring sensor is attached directly to the evaluation electronics.

The protection of the electronic components against solvents etc. is further increased in a preferred embodiment in that the pressure measuring chamber is closed in a fluid-tight manner with respect to the rest of the interior of the housing. The rest of the interior of the housing can preferably be filled with a protective gas, for example helium.

A preferred exemplary embodiment, in which the pressure measuring chamber is filled with a pressure measuring fluid, is distinguished by a particularly high measuring accuracy. In particular, non-electrically conductive oils such. B. silicone-based, proven.

In the case of a preferred exemplary embodiment, a data memory is provided in the housing, from and / or to which data can be transmitted, the data preferably being able to be transmitted without contact.

A digital pressure measuring unit which can be particularly advantageously integrated into a paint spray gun is obtained in that the digital pressure measurement unit is designed in such a way that it can be attached to a handle of the paint spray gun, preferably can form part of the handle.

In the case of an alternative embodiment, the digital pressure measuring unit is designed in such a way that it can be attached in the area of an air pressure and / or material pressure setting device (micrometer) or is even integrated into the setting device.

The invention is also carried out by a paint spray gun which is designed for the, preferably compressed air-assisted, atomization and application of a coating material, in particular a paint, and which has a digital pressure measuring unit described above and below.

• 1 eine Lackierpistole mit einer austauschbaren Digitaldruckmesseinheit,
• 2 eine Schnittdarstellung der Lackierpistole gemäß 1 im Bereich der Digitaldruckmesseinheit,
• 3 beispielhafte Ausführungen der Anzeige mit einem (optionalen) Touchpad einer Digitaldruckmesseinheit,
• 4 eine ausschnittsweise Schnittdarstellung einer alternativen Ausführung einer Digitaldruckmesseinheit im Bereich des Druckluftanschlusses und
• 5 eine ausschnittsweise Schnittdarstellung einer alternativen Ausführung einer Digitaldruckmesseinheit im Verbindungsbereich einer Deckplatte mit dem Gehäuse der Digitaldruckmesseinheit.

The invention is explained below on the basis of exemplary embodiments. The figures show:

• 1 a spray gun with an exchangeable digital pressure measuring unit,
• 2 a sectional view of the spray gun according to 1 in the area of the digital pressure measuring unit,
• 3 exemplary designs of the display with an (optional) touchpad of a digital pressure measuring unit,
• 4th a partial sectional view of an alternative embodiment of a digital pressure measuring unit in the area of the compressed air connection and
• 5 a partial sectional view of an alternative embodiment of a digital pressure measuring unit in the connection area of a cover plate with the housing of the digital pressure measuring unit.

In 1 is a hand-held spray gun 1 shown for compressed air-assisted atomization and application of a coating material. The paint gun 1 can be used, for example, as a so-called Compliant or HVLP spray gun 1 be trained. The paint gun 1 has a connector 2 for z. B. a filled with a coating material (not shown) gravity cup and a nozzle head 3 at which the atomized coating material emerges. It also includes the spray gun 1 a handle 4th , a trigger guard 5 for one inside the paint gun 1 arranged paint needle, an adjustment mechanism 6th for the stroke of the paint needle (material quantity regulation), an air pressure setting device 7th (Micrometer), a round / wide beam adjustment device 8th as well as a compressed air connection 9 . By means of the round / wide jet adjustment device 8th can distribute the compressed air supplied to z. B. the atomization and transport air on the one hand and the horn air on the other hand can be changed.

For the properties of the means of the spray gun 1 generated spray jet are, among other things, the (dynamically) established air pressures with which the various air flows of the atomizing, transport and horn air are supplied to the coating material to be atomized. These air pressures are in turn determined by the spray gun 1 applied input air pressure influenced by means of the air pressure setting device 7th is adjustable.

In order to achieve an optimal painting result, paint manufacturers often specify an inlet air pressure to be set depending on the paint used and the spray gun used (including nozzle size, etc.).

In order to measure and display the inlet air pressure or the air pressure occurring elsewhere (and thus to be able to set it to the specified value), the spray gun 1 a digital pressure measuring unit 10 on. The digital pressure measuring unit 10 is exchangeable in the handle 4th the spray gun 1 arranged. A compressed air duct 11 leads the digital pressure measuring unit 10 Compressed air from one place 12th in the spray gun 1 to which air pressure is to be measured. The measuring point is located in the exemplary embodiment shown 12th in the air duct system through the spray gun 1 after the air pressure adjustment device 7th and in front of the round / wide jet adjustment device 8th .

In 2 is a detail of a sectional view through the handle 4th arranged digital pressure measuring unit 10 shown. The unit 10 is through a housing 13th educated. For example, the housing 13th Made of stainless steel and designed in the shape of a cuboid. The case 13th has a first and an opposite second recess 14th , 15th in the form of windows or openings. Preferably the housing is 13th otherwise closed, ie it has no further recesses, bores, etc.

The first recess 14th is through a pressure transmission membrane 16 sealed fluid-tight, on which a pressure measuring chamber 17th that borders inside the case 13th is arranged. The pressure transmission membrane 16 is on the outside of the case 13th from an elastic connection seal 18th surrounded on the outside of the housing 13th is attached interchangeably. By the connection seal 18th on the inside wall 19th a recess 20th in the handle 4th the spray gun 1 becomes an air chamber 21 sealed to the environment, in which the compressed air duct 11 flows out.

The pressure transmission membrane 16 is by means of a welded joint 22nd , the z. B. is formed by laser welding with the outside of the housing 13th connected. The pressure measuring chamber 17th is opposite the rest of the interior of the digital pressure measuring device 10 through a wall 23 closed. Alternatively, the pressure measuring chamber 17th also through the entire interior of the housing 13th be educated.

In the pressure measuring chamber 17th is a pressure measuring sensor 24 provided with one inside the housing 13th arranged evaluation electronics 39 connected is. Alternatively, the pressure measuring sensor 24 directly on the evaluation electronics 39 be arranged or integrated in this.

The pressure measuring chamber 17th is with a pressure measuring fluid, e.g. B. a non-electrically conductive oil, for example based on silicone, filled, with the rest of the interior of the housing 13th is filled with a protective gas, for example helium.

The second recess 15th of the housing 13th is through a transparent cover plate in the form of a pane of glass 25th fluid-tight closed by means of a pocket on the housing side 26th arranged, diffusion-tight adhesive connection 27 on the housing 13th is connected. Over the glass 25th is one inside the case 13th arranged display 28 visible. In the further is the plate 25th with a capacitive touch field 29 Mistake.

In an alternative embodiment using wireless data transmission, a display and a touch field can be omitted and the cover plate can be made of plastic or metal, for example. In this case, the cover plate is preferably welded to the housing in a hermetically sealed manner.

the display 28 forms an electronic unit with the evaluation electronics 39 . In addition, there is in the evaluation electronics 39 a data store 30th integrated, from and to the data contactless (e.g. via Bluetooth) from outside the housing 13th can be transferred. For example, a short-term activation of a readout function for the stored data by means of the touch field 29 respectively.

One also from outside the case 13th (about the one with the glass pane 25th covered second recess 15th ) contactless chargeable double-layer capacitor 31 serves to supply the digital pressure measuring unit with energy 10 , whereby the power supply is inductive via a charging coil 32 he follows.

Overall, the result is a hermetically sealed digital pressure measuring unit 10 with touch field 29 that can be operated without a battery. The digital pressure measuring device 10 is characterized by a simple holder without a cover plate and thus simplifies assembly on the spray gun 1 and removal from the spray gun 1 . If repairs are possible, the unit 10 simply in 2 to the left out of the handle 4th to be pulled. The elastic connection seal 18th prevents the penetration of z. B. Solvents during operation.

In 3 are examples of the form and content of the display 28 the digital pressure measuring unit 10 shown. It can be seen that in addition to a rectangular shape, the display also has a circular shape 28 it is a possibility. the display 28 includes a display area 33 , in which the measured pressure value is displayed in the case shown. In addition, are still through the touch field 29 formed controls 34 shown. In addition to the pressure values, other content can also be displayed, e.g. B. Total spray duration, last set pressures, other texts, etc.

In 4th is a further connection variant of the digital pressure measuring device 10 shown in which the housing 13th with a connecting piece 35 is provided, on which an O-ring-shaped connection seal 36 is raised. The mounting of the digital pressure measuring unit on the spray gun side 10 is in the 4th Not shown. It goes without saying, however, that the receptacle corresponds to the connection piece 35 is listed. In addition, many other known forms of connection are possible via nozzles, cones, etc., which are reliably tight and detachable even without an additional seal by pure form fit.

In 5 is another way of fixing the glass pane 25th on the housing 13th shown. In this case it is the pane of glass 25th by means of a locking frame 37 on the housing 13th attached and with the help of an intermediate housing 13th and glass pane 25th arranged seal 38 sealed from elastomer.

The pane of glass 25th or a different type of cover plate can, however, also be sealed by means of a sprayed-on elastomer and fixed with a welded frame. Furthermore, it can also be tightly and firmly connected to the frame by caulking or a press fit with or without a cone. Alternatively, the glass pane or the cover plate can be glued in a diffusion-tight manner with a highly filled two-component adhesive.

In an alternative embodiment (not shown), the coating material can be supplied to the spray gun under pressure or put under pressure in the spray gun. In this case, the material pressure can be measured and displayed by means of the digital pressure measuring unit, in that no compressed air channel but a material channel leads to the digital pressure measuring unit. It is even conceivable that, by means of a modified digital pressure measuring unit, both the air pressure and the material pressure, e.g. B. can be measured and displayed by means of two separate pressure measuring chambers.

List of reference symbols

1.

Spray gun

2.

connection

3.

Nozzle head

4th

Handle

5.

Trigger guard

6th

Adjustment mechanism

7th

Air pressure adjustment device

8th.

Round / wide jet adjustment device

9.

Compressed air connection

10.

Digital pressure measuring unit

11.

Compressed air duct

12th

Measuring point

13th

casing

14th

first recess

15th

second recess

16.

Pressure transmission membrane

17th

Pressure measuring chamber

18th

Connection seal

19th

Inner wall

20th

Recess

21.

Air chamber

22nd

Welded joint

23

Wall

24

Pressure measuring sensor

25th

Cover plate

26th

bag

27

Adhesive connection

28.

Display

29

Touch field

30th

Data storage

31.

Double layer capacitor

32.

Charging coil

33.

Display area

34.

Controls

35.

Connection piece

36.

Connection seal

37.

frame

38.

poetry

39.

Evaluation electronics

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• EP 3421140 A1 [0003, 0005]

Claims (13)

Digital pressure measuring unit (10), in particular exchangeable digital pressure measuring unit (10), which is designed to measure and display an air pressure and / or a material pressure, in particular an air pressure and / or material pressure in or on a spray gun (1) for atomization and application, preferably with the aid of compressed air a coating material, in particular a lacquer, characterized in that the digital pressure measuring unit (10) is formed by a housing (13) which has a recess (14) which is closed in a fluid-tight manner by a pressure transmission membrane (16) to which inside of the housing (13) is bounded by a pressure measuring chamber (17). Digital pressure measuring unit (10) Claim 1 , characterized in that the pressure transmission membrane (16) is surrounded on the outside of the housing (13) by a connection seal (18). Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that the pressure transmission membrane (16) is positively, non-positively and / or cohesively connected to the housing (13), preferably by means of a weld (22) and / or Adhesive connection. Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that the pressure transmission membrane (16) on the outside of the housing (13) is connected to the latter. Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that the housing (13) has a recess (15) which is closed in a fluid-tight manner by a cover plate (25), in particular an at least partially transparent cover plate (25), the Cover plate (25) is positively, non-positively and / or cohesively connected to the housing (13), preferably by means of a welded connection, an adhesive connection (27) and / or by means of a latching frame (37), and / or the cover plate preferably with the recess is provided, which is closed by the pressure transmission membrane. Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that the housing (13) has a recess (15) which is closed in a fluid-tight manner by a cover plate (25), via which display electronics arranged within the housing (13), preferably a display (28) is visible, in particular the cover plate (25) is provided with a touch field (29). Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that for the energy supply of the digital pressure measuring unit (10) inside the housing (13) an energy store, preferably a rechargeable energy store, further preferably a contactlessly rechargeable energy store from outside the housing (13), for example in the form of a double layer capacitor (31) is provided. Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that a pressure measuring sensor (24) is provided in the pressure measuring chamber (17), which is connected to evaluation electronics (39) arranged inside the housing (13), preferably on the evaluation electronics (39) is applied. Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that the pressure measuring chamber (17) is sealed fluid-tight with respect to the remaining interior of the housing (13), the remaining interior of the housing (13) preferably being filled with a protective gas, for example helium is. Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that the pressure measuring chamber (17) is filled with a pressure measuring fluid. Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that a data memory (30) is provided in the interior of the housing (13), from and / or to which data can be transmitted, the data preferably being able to be transmitted without contact. Digital pressure measuring unit (10) according to one of the preceding claims, characterized in that the digital pressure measuring unit (10) is designed in such a way that it can be attached to a handle (4) of the spray gun (1), preferably forming part of the handle (4) . Paint spray gun (1) for compressed air-assisted atomization and application of a coating material, in particular a paint, with a digital pressure measuring unit (10) according to one of the preceding claims.

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