EP3165288A1 - Jet device - Google Patents

Abstract

A spray device (1) for spraying a fluid with a metering device (2), in particular an eccentric screw pump, for volumetric metering of the fluid and a spraying device (34), which is adapted to the metered by the metering device (2) fluid with the aid of a gas to spray.

Description

The present invention relates to a spraying device for spraying a fluid.

The spraying of fluids or fluid media, such as adhesives or sealants, paints, suspensions, viscous raw materials, emulsions or fats, for example, can be done using a Venturieffekt based spray device. A Venturi nozzle comprises a smooth-walled pipe section with a narrowing of the cross section, for example by two oppositely directed cones, which are united at the point of their smallest diameter. At this point, a pick-up tube is placed, via which the fluid to be sprayed can be supplied. The supplied fluid is entrained and sprayed by means of a gas flowing through the venturi, for example air.

Against this background, an object of the present invention is to provide an improved spraying apparatus.

Accordingly, a spray device for spraying a fluid is proposed. The spraying device comprises a metering device, in particular an eccentric screw pump, for the volumetric metering of the fluid and a spraying device, which is set up to spray the fluid metered by the metering device with the aid of a gas.

The metering device is in particular a first metering device of the spraying device. The spray device may comprise a plurality, for example two, metering devices. The metering device preferably comprises a stator accommodated in a pump housing of the metering device, which has an elastically deformable elastomer part with a central opening. The breakthrough preferably comprises a helical or helical inner contour. In the stator, a rotatable rotor is preferably provided, the a corresponding to the elastomeric part screw or helical outer contour comprises. The rotor can be driven via a drive shaft mounted in a bearing housing of the metering device. A drive device, in particular an electric motor, can preferably be connected to the drive shaft. The drive shaft may be fixedly connected to the rotor by means of a flexible shaft or flex shaft. As the rotor is rotated, the fluid is conveyed away from the endless-piston drive shaft by interaction with the elastomeric part of the stator in a longitudinal direction of the sprayer. The delivery volume depends on the speed and size of the rotor.

By volumetric dosing is meant that the fluid discharge takes place exclusively volume and thus volume-related. In contrast, in a gravimetric or weight-controlled metering system, the fluid to be metered is weighed with a weighing device. Optionally, a temperature sensor can be used to determine a temperature of the fluid. The temperature sensor may be provided in the fluid or in the pump housing. With the help of the temperature of the fluid detected by the temperature sensor, the delivery volume can be readjusted. As a result, heat-related volume changes of the fluid are compensated and dose inaccuracies avoided.

The fluid may be, for example, an adhesive or sealant, water, an aqueous solution, a paint, a suspension, a viscous raw material, an emulsion, or a fat. The fluid may have one or more than one component. For example, the fluid may be a two-component adhesive. The gas is preferably air. The gas may also be oxygen, carbon dioxide, nitrogen, a noble gas or other gas. The fact that the fluid is metered volumetrically, this can be sprayed with high accuracy. In particular, metering of the fluid can be independent of the pre-spraying thereof. The venturi effect is not used for spraying the fluid. This prevents the fluid from being torn out of a metering needle of the metering device becomes. As a result, a spalling or islanding is prevented on a substrate to be sprayed.

Because the fluid can be metered volumetrically and independently of the gas supply, the gas can be switched on before the metering of the fluid and switched off again only after the metering has ended. That is, the metered with the metering amount of fluid can be slowly increased with switched on gas to the desired metering and also be continuously reduced with still switched on gas. As a result, a ramp-like starting and stopping the spraying process is possible. In particular, the volume flow of the fluid and the volume flow of the gas can be controlled independently. As a result, the spray pattern is variably variable to a large extent.

A method for operating the spraying device comprises a, in particular first, step of volumetric metering of the fluid and a, in particular second, step of spraying the metered fluid with the aid of the gas. The steps can be performed simultaneously or with a time delay.

According to one embodiment, the spraying device further comprises a heating and / or cooling device for heating or cooling the fluid in order to change its viscosity.

In particular, by the heating or cooling of the fluid whose spray properties can be changed. For example, this can be used to heat a highly viscous fluid in order to reduce its viscosity. Alternatively, a low viscosity fluid can be cooled to increase its viscosity. This makes it possible to spray both low-viscosity and high-viscosity fluids. A control device of the spray device can readjust the metering of the fluid with the aid of the determined temperature of the fluid by accessing a viscosity table stored in the control device. hereby Dosage inaccuracies can be prevented by thermal expansion of the fluid.

According to a further embodiment, the heating and / or cooling device is arranged in a pump housing of the metering device.

Alternatively, the heating and / or cooling device can be arranged on the outside of the pump housing in the form of a sleeve. The heating and / or cooling device further comprises a temperature sensor, which is preferably also arranged in the pump housing. The heating and / or cooling device further comprises a printed circuit board or board on which heating and / or cooling elements such as heating cartridges and / or Peltier elements are arranged. On the circuit board, a plug for connecting the heating and / or cooling device may be further provided with the control device of the spray device.

According to a further embodiment, the spray device comprises a spray head with a gas cap and a dispensing needle, which is guided through the gas cap, wherein the dispensing needle protrudes in a longitudinal direction of the spray device on the gas cap.

The dispensing needle can also be flush with the gas cap or shorter than this. This means that the dispensing needle can be behind the gas cap. For example, the dosing needle can be located 0 to 1 mm behind the gas cap. The spray head preferably further comprises an air or gas housing with a gas supply line. The gas supply line may include a quick release for connecting a gas line. The air or gas cap is preferably secured by means of a union nut on the gas housing. The union nut may have a knurling on the outside, so that it can be unscrewed without tools. The gas cap is in particular exchangeable for adaptation to different fluids and / or for changing the spray pattern. The gas cap preferably has a conical bore, in which the preferably also outside conical dispensing needle is arranged. The dispensing needle and / or the gas cap can be surface-treated, in particular surface-coated, hardened or passivated. In particular, the dispensing needle and / or the gas cap can be surface-treated such that very reactive and / or abrasive fluids can be sprayed. For example, the gas cap on the inside and / or the dispensing needle on the outside of a diamond-like amorphous carbon coating (Diamond-Like Carbon, DLC) have. In particular, the dispensing needle protrudes beyond the gas cap with a predetermined projection. The predetermined supernatant may for example be 0 to 1 mm. This means that the dispensing needle can also be flush with the gas cap. The supernatant can be changeable. The fact that the dispensing needle protrudes beyond the gas cap, in addition to the spraying of the fluid and a dosing of the same is possible directly to a substrate. Furthermore, the dispensing needle can be negative and the substrate can be positive or, conversely, electrically charged. As a result, a better spray pattern, a better edge sharpness and less blobbing are achieved.

According to a further embodiment, a circumferential gap for the gas is provided between the gas cap and the dispensing needle.

The gap preferably surrounds the dispensing needle like a jacket. In the gas housing, an annular circumferential gas passage for distributing the gas is preferably provided.

According to a further embodiment, the spray head comprises a swirl element for swirling the gas.

The vortex element may be provided in the circumferential gap. There may be more than one vortex element. For example, helical or spiral ribs and / or helical or spiral cut-outs adapted to fluidize the gas may be provided on the dispensing needle and / or on the gas cap. As a result, the gas enters with a Spin out of the spray head. As a result, a sharper edge and more uniform spray pattern is achieved.

According to a further embodiment, the vortex element is made of a porous plastic, ceramic or metal material.

The vortex element may for example be made of a sintered ceramic or metal material. For example, the vortex element can be made of aluminum or steel. Preferably, the fluid flows through the vortex element. In particular, the entire gap between the dispensing needle and the gas cap is filled with the porous vortex element. The vortex element may be in one piece or in several parts. The gas flows through the vortex element. With the help of the vortex element, the gas can be indeterminate, that is chaotic, swirling.

According to a further embodiment, the dispensing needle is materialeinstückig or positively connected to an end of the metering device.

Preferably, the tail is firmly connected to the pump housing, for example screwed. The stator may be clamped between the pump housing and the tail. For example, the dispensing needle may be screwed into the end piece. As a result, a simple replacement of the dispensing needle is possible. Alternatively, the dispensing needle may be integrally formed with the end piece. As a result, dead space optimization can be achieved. This is particularly advantageous in a filigree design of the spray head. Preferably, both the dispensing needle and the gas cap are interchangeable.

According to a further embodiment, the dispensing needle and / or the gas cap are adjustable in length.

Preferably, the gas cap on a gas pipe, whose length is adjustable, for example by means of a locking fitting. By doing that, the gas cap is adjustable in length, the supernatant of the dispensing needle can be adjusted via the gas cap. In this way, a spray angle of the spray device can be adjusted without an exchange of components. Optionally, the gas cap may include a tubular gas cap extension. A length of the gas cap process extension is preferably arbitrary. The dispensing needle may have a dispensing needle extension corresponding to the gas cap extension, which protrudes in the longitudinal direction preferably over the gas cap extension. Furthermore, the dispensing needle can be designed as an exchangeable disposable component. In particular, the dispensing needle may be a disposable cannula. The dispensing needle may have a connection body made of a plastic material and a cannula. The connecting body preferably has an inner cone into which a corresponding outer cone of the end piece can be inserted. The inner cone and the outer cone can form a luer-lock connection. As a result, the dispensing needle is particularly easy and quick to replace.

According to a further embodiment, the metering device is adapted for the volumetric metering of a first component of the fluid, wherein the spraying device comprises a further metering device, in particular an eccentric screw pump, for the volumetric metering of a second component of the fluid.

In particular, a spray device for spraying a fluid with a first metering device, in particular a first eccentric screw pump for volumetric metering of a first component of the fluid, a second metering device, in particular a second eccentric screw pump, for volumetric metering of a second component of the fluid and a spray device is proposed which is adapted to spray the fluid with the aid of a gas. Preferably, the spraying device is a common spraying device of the first metering device and the second metering device. In particular, the spraying device is set up to spray the first component metered by the first metering device and the second component of the fluid metered by the second metering device with the aid of the gas. The fluid may include other components in addition to the first component and the second component. The fluid may be, for example, a two-component adhesive. The components may be mixed either before spraying or during spraying into the fluid.

According to a further embodiment, the spraying device comprises a mixing chamber for mixing the first component of the fluid with the second component of the fluid before spraying the fluid by means of the spraying device.

The mixing chamber is particularly suitable for mixing ratios of the components from 1: 1 to 1: 5. Alternatively, can be dispensed with the mixing chamber.

According to a further embodiment, the spraying device further comprises a mixing element arranged in the mixing chamber for dynamically mixing the first component of the fluid with the second component of the fluid.

The mixing element may also be referred to as a dynamic mixing element. The mixing element is preferably rotatably arranged in the mixing chamber. In particular, the mixing element is driven via a mixing element drive shaft. The mixing element drive shaft can be driven for example by means of an electric motor. By using the rotatable mixing element, in particular mixing ratios of the components of the fluid of, for example, 1: 1 to 1: 100 can be achieved.

According to a further embodiment, the spraying device further comprises a static mixer arranged in the mixing chamber for mixing the first component of the fluid with the second component of the fluid.

A static mixer is a fixture that achieves the desired mixing and dispersion effects by flowing the components of the fluid through rigid mixing elements.

According to a further embodiment, the spraying device further comprises a spray head with a dispensing needle, which is adapted to mix the first component of the fluid with the second component of the fluid.

The dispensing needle can be made in several parts. In particular, the dispensing needle comprises an inner part with a central first fluid channel, through which the first component of the fluid is conveyed. The dispensing needle may further comprise an outer part which is attached to the inner part. Between the inner part and the outer part, a second fluid channel may be provided, through which the second component of the fluid is conveyed. The second fluid channel encloses the inner part like a jacket. That is, in the dosing of the components of the fluid they are not mixed but emerge as two components of the dispensing needle on the front side. The mixing of the components takes place in that the components are swirled during the spraying with the aid of the gas and thereby mixed.

According to a further embodiment, the dispensing needle comprises a static mixing element.

The static mixing element may also be referred to as a static mixer. The static mixer may be provided in the dispensing needle. That is, the first component and the second component are mixed in dosing.

Further possible implementations of the spraying device also include combinations of non-explicitly mentioned combinations of features or embodiments described above with regard to the exemplary embodiments. The expert will also add individual aspects as improvements or additions to the respective basic form of the spray device.

• Fig. 1 zeigt eine schematische perspektivische Ansicht einer Ausführungsform einer Sprühvorrichtung;
• Fig. 2 zeigt eine schematische Seitenansicht der Sprühvorrichtung gemäß Fig. 1;
• Fig. 3 zeigt eine schematische Rückansicht der Sprühvorrichtung gemäß Fig. 1;
• Fig. 4 zeigt eine schematische Schnittansicht der Sprühvorrichtung gemäß der Schnittlinie A - A der Fig. 2;
• Fig. 5 zeigt eine schematische Schnittansicht der Sprühvorrichtung gemäß der Schnittlinie B - B der Fig. 3;
• Fig. 6 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung;
• Fig. 7 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung;
• Fig. 8 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung;
• Fig. 9 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung;
• Fig. 10 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung;
• Fig. 11 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung;
• Fig. 12 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung;
• Fig. 13 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung;
• Fig. 14 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung; und
• Fig. 15 zeigt eine schematische Schnittansicht einer weiteren Ausführungsform einer Sprühvorrichtung.

Further advantageous embodiments and aspects of the spraying device are the subject of the subclaims and the embodiments of the spraying device described below. In the following, the spraying device will be explained in more detail on the basis of preferred embodiments with reference to the enclosed figures.

• Fig. 1 shows a schematic perspective view of an embodiment of a spraying device;
• Fig. 2 shows a schematic side view of the spray device according to Fig. 1 ;
• Fig. 3 shows a schematic rear view of the spray device according to Fig. 1 ;
• Fig. 4 shows a schematic sectional view of the spraying device according to the section line A - A of Fig. 2 ;
• Fig. 5 shows a schematic sectional view of the spray device according to the section line B - B of Fig. 3 ;
• Fig. 6 shows a schematic sectional view of another embodiment of a spraying device;
• Fig. 7 shows a schematic sectional view of another embodiment of a spraying device;
• Fig. 8 shows a schematic sectional view of another embodiment of a spraying device;
• Fig. 9 shows a schematic sectional view of another embodiment of a spraying device;
• Fig. 10 shows a schematic sectional view of another embodiment of a spraying device;
• Fig. 11 shows a schematic sectional view of another embodiment of a spraying device;
• Fig. 12 shows a schematic sectional view of another embodiment of a spraying device;
• Fig. 13 shows a schematic sectional view of another embodiment of a spraying device;
• Fig. 14 shows a schematic sectional view of another embodiment of a spraying device; and
• Fig. 15 shows a schematic sectional view of another embodiment of a spraying device.

In the figures, the same or functionally identical elements have been given the same reference numerals, unless stated otherwise.

The Fig. 1 shows a schematic perspective view of an embodiment of a spray device 1 for spraying a fluid. The Fig. 2 shows a schematic side view of the spray device 1. The Fig. 3 shows a schematic rear view of the spray device 1. The Fig. 4 shows a schematic sectional view of the spray device 1 according to the section line A - A of Fig. 2 and the Fig. 5 shows a schematic sectional view of the spray device 1 according to the section line B - B of Fig. 3 , The following is on the Fig. 1 to 5 simultaneously referred to.

The spray device 1 is adapted to fluids or fluid media, such as adhesives or sealants, paints, suspensions, viscous raw materials, To dose and spray emulsions or greases. The fluid may be one-component or multi-component. The spraying device 1 comprises a, in particular first, metering device 2 for the volumetric metering of the fluid. By volumetric dosing is meant that the fluid discharge takes place exclusively volume and thus volume-related. In contrast, in a gravimetric or weight-controlled metering system, the fluid to be metered is weighed with a weighing device.

The metering device 2 is an eccentric screw pump. The spraying device 1 comprises a symmetry or central axis M ₁ and oriented in the direction of the central axis M ₁ longitudinal direction _L1. The metering device 2 comprises a rotatably mounted in a bearing housing 3 drive shaft 4. The drive shaft 4 is a hollow shaft. The drive shaft 4 is preferably made of a steel material and the bearing housing 3 is preferably made of a metal material, such as aluminum or steel, or a plastic material. The drive shaft 4 is rotatably supported in the bearing housing 3 by means of rolling bearings 5, 6. The rolling bearings 5, 6 can be designed as a double-row angular contact ball bearings. The rolling bearings 5, 6 are secured by means of a securing ring 7 in the axial direction in the bearing housing 3. On the drive shaft 4, a drive device, in particular an electric motor, can be connected. The drive device can be coupled to the drive shaft 4 with the aid of a dog clutch 8. The dog clutch 8 may be made of an elastomeric material.

The drive shaft 4 is further passed through a fixedly connected to the bearing housing 3 seal housing 9. The bearing housing 3 and the seal housing 9 may be formed rotationally symmetrical to the central axis M ₁ . In the seal housing 9 are received a plurality of sealing devices 10 to 12 arranged one behind the other. The sealing devices 10 to 12 may be, for example, shaft sealing rings. The bearing housing 3 is by means of fastening means 13, of which in the Fig. 3 and 4 only one is provided with a reference numeral, bolted to the seal housing 9. The fastening means 13 may be, for example, hexagon socket screws. Between the bearing housing 3 and the seal housing 9, a sealing element 14 may be provided. The sealing element 14 may be an O-ring. The seal housing 9 is preferably made of a metal material, such as aluminum or steel, or a plastic material.

The metering device 2 further comprises a pump housing 15. The pump housing 15 is preferably made of a metal material, such as aluminum or steel, or a plastic material. The pump housing 15 may also be formed rotationally symmetrical to the central axis M ₁ . Between the seal housing 9 and the pump housing 15, a sealing element 16, in particular an O-ring, can be arranged. The pump housing 15 can be firmly connected to the bearing housing 3 and / or the seal housing 9, in particular screwed, be. In this case, the seal housing 9 is arranged between the bearing housing 3 and the pump housing 15.

In the pump housing 15, a stator 17 is arranged. The stator 17 comprises a tubular outer part 18, which is preferably made of a metal material, such as aluminum or steel, or a plastic material, such as polyethylene or polypropylene, and an elastomeric part 19, which is made of an elastomeric material. The outer part 18 may also be referred to as stator jacket or stator tube. The elastomer part 19 has a central opening with a helical or helical inner geometry or inner contour. The stator 17 is secured in the pump housing 15 by means of a feather key or a dowel pin 20 from twisting. The stator 17 is arranged between a shoulder 21 provided in the pump housing 15 and an end piece 22 of the metering device 2. The end piece 22 is preferably made of a metal material, such as aluminum or steel, or a plastic material. The end piece 22 is bolted to the pump housing 15, for example. The stator 17 is clamped axially in the longitudinal direction L ₁ between the pump housing 15 and the end piece 22.

In the stator 17, a rotatable rotor 23 is arranged. The rotor 23 may be made of steel, aluminum or a plastic material. The rotor 23 has a helical or helical outer geometry or outer contour. The rotor 23 is fixedly connected to the drive shaft 4 by means of a flexible shaft or flexible shaft 24. The flex shaft 24 may be provided on the outside with a coating or a passivation. For example, the flex shaft 24 may be surrounded by a rubber jacket. As a result, a chemical reaction of the fluid with the material of the flex shaft 24 is excluded. The stator 17 and the rotor 23 are interchangeable, so that the delivery volume of the metering device 2 is variable.

Via a supply opening 25 provided in the pump housing 15, the metering device 2 can be supplied with the fluid. The supply port 25 may also be referred to as product input. The feed opening 25 is oriented perpendicular to the central axis M ₁ . The fluid enters from the supply opening 25 into a receiving space 71 provided in the pump housing 15. The receiving space 71 may also be referred to as a pump interior. The receiving space 71 is provided in the pump housing 15 bore extending in the longitudinal direction L ₁ . In the receiving space 71 and the flex shaft 24 is arranged. From the receiving space 71, the fluid is transported by means of the rotating rotor 23 in the longitudinal direction L ₁ in the direction of the end piece 22. The metered volume is speed-dependent.

A tubular venting device 26 for venting the metering device 2 can furthermore be provided on the pump housing 15. The venting device 26 is screwed into a provided on the pump housing 15 vent hole 27. The vent hole 27 may be arranged perpendicular to the central axis M ₁ . The end piece 22 and the pump housing 15 may be pinned together by means of dowel pins 28 and additionally screwed.

The metering device 2 further comprises a heating and / or cooling device 29. The heating and / or cooling device 29, as in the Fig. 5 shown to be disposed in the pump housing 15. Alternatively, the heating and / or cooling device 29 may be provided on the outside of the pump housing 15 in the form of a sleeve. With the help of the heating and / or cooling device 29, the viscosity of the fluid can be changed. For example, highly viscous fluids can be heated with the aid of the heating and / or cooling device 29 in order to reduce their viscosity, as a result of which even highly viscous fluids can be metered easily and reliably with the aid of the metering device 2. Alternatively, the heating and / or cooling device 29 may also be adapted to reduce the viscosity of the fluid by cooling, whereby low-viscosity fluids with the aid of the metering device 2 are easily and reliably metered.

The heating and / or cooling device 29 may have a plurality, for example two, heating and / or cooling elements 30, 31. The heating and / or cooling elements 30, 31 can be, for example, heating cartridges or Peltier elements. The heating and / or cooling device 29 further comprises a temperature sensor, not shown, and a printed circuit board 32. On the circuit board 32, a plug 33 (FIG. Fig. 2 ) be provided. With the help of the plug 33, the heating and / or cooling device 29 can be connected to a control device. The heating and / or cooling device 29 is optional.

The spraying device 1 further comprises a spraying device 34, which is set up to spray the fluid metered by the metering device 2 with the aid of a gas. The gas is particularly pressurized. The gas may be, for example, air, carbon dioxide, nitrogen, a noble gas or any other gas. Preferably, the gas is air. The spraying device 34 comprises a gas housing 35, which by means of fastening means 36, of which in the Fig. 4 only one is provided with a reference numeral, is fixedly connected to the end piece 22. The gas housing 35 may also be referred to as an air housing. The gas housing 35 is preferably made of a metal material, such as aluminum or steel, or a plastic material. The fasteners 36 may be, for example, hexagon socket screws. Between the end piece 22 and the gas housing 35, a sealing element 37, in particular an O-ring, can be arranged.

On the gas housing 35, a gas supply line 38 is provided. The gas supply line 38 is formed for example as L-push-in fitting. The gas supply line 38 may be screwed into a provided on the gas housing 35 gas supply hole 39. The gas supply hole 39 is arranged, for example, perpendicular to the central axis M ₁ . The gas supply line 38 is adapted to divert the gas by 90 °. The gas supply line 38 may have a quick release for connecting a gas line thereto.

The spray device 34 comprises a spray head 40 with a metering needle 41 associated with the metering device 41 and a gas cap 42. The gas cap 42 may also be referred to as an air cap. The gas cap 42 is preferably made of a metal material, such as aluminum or steel, or a plastic material. The dispensing needle 41 is preferably made of a metal material, such as aluminum or steel, or a plastic material. The dispensing needle 41 is materialeinstückig formed with the end piece 22 or is, as in the Fig. 4 and 5 shown frontally screwed into the end piece 22. The gas cap 42 has a central conical opening through which the dispensing needle 41 is passed. In this case, between the dispensing needle 41 and the gas cap 42 a metering needle 41 shell-shaped circumferential gap 43 is formed for the gas.

As the Fig. 2 shows the metering needle 41 and the gas cap 42 can be replaced. In this way, the spray pattern of the spray device 1 can be changed and / or an adaptation of the spray head 40 to different fluids. Furthermore, vortex elements or vertebral bodies for swirling the gas may be provided in the gap 43. For example, screw-shaped or spiral-shaped ribs and / or helical or spiral cut-outs may be provided on the dispensing needle 41 and / or on the gas cap 42 are designed to swirl the gas. As a result, the gas exits the spray head 40 with a twist. Furthermore, the metering needle 41 on the outside and / or the gas cap 42 may be surface-treated on the inside, for example passivated, hardened or coated. For example, a DLC coating can be used. As a result, very reactive and / or abrasive fluids can be sprayed.

The gas cap 42 is connected by means of a union nut 44 with the gas housing 35. The union nut 44 can, as in the Fig. 2 shown, have a knurling 45 on the outside. As a result, an easy replacement of the gas cap 42 is possible. As the Fig. 2 Furthermore, the dispensing needle 41 can protrude in the longitudinal direction L ₁ by a supernatant a via the gas cap 42. Alternatively, the dispensing needle 41 may be flush with or behind the gas cap 42. The supernatant a may be for example 0 to 1 mm. The gap 43, the gas is supplied via a ring around the end piece 22 encircling gas channel 46. Between the gas cap 42 and the end piece 22, a sealing element 68, in particular an O-ring, is provided.

The operation of the spray device 1 will be explained below. About the supply port 25 of the spray device 1 is supplied to the fluid to be sprayed. The amount of fluid to be metered is adjusted via the rotational speed of the rotor 23. The metering can initially be carried out independently of the spraying. The metered amount of the fluid can also be influenced by different geometries of the rotor 23 and / or of the stator 17. Via the gas supply line 38, the pressurized gas is supplied, which is distributed uniformly via the gas channel 46. The gas exits via the gap 43 on the front side of the gas cap 42, wherein the escaping gas travels with the exiting from the dosing needle 41 fluid and sprayed. When exiting the gas cap 42, the gas is preferably vortexed, whereby a particularly uniform and sharp-edged spray pattern can be generated.

Depending on the amount of the metered fluid, a different spray pattern on a substrate to be sprayed can be achieved with a constant gas flow. The dosage of the fluid is purely volumetric and not by a Venturi effect. As a result, it is possible to dispense with a valve in the dispensing needle 41, because no vacuum is produced on the dispensing needle 41, which tears the fluid out of the dispensing needle 41. Characterized in that the fluid is metered volumetrically and independently of the gas supply, the gas can be switched on before the metering of the fluid and turned off only after the completion of dosing. That is, the metered with the metering device 2 amount of fluid can be slowly increased with switched on gas to the desired metering and also be continuously reduced with still switched on gas. As a result, a ramp-like starting and stopping the spraying process is possible.

The gas can also be supplied in pulses. In addition, a temperature sensor can be used to determine a temperature of the fluid. A control device of the spray device 1 can readjust the metering of the fluid with the aid of the determined temperature of the fluid by accessing a viscosity table stored in the control device. As a result, metering inaccuracies can be prevented by thermal expansion of the fluid. The temperature sensor may be associated with the heating and / or cooling device 29.

Because the dispensing needle 41 protrudes beyond the gas cap 42, the fluid can also be dispensed directly onto the substrate to be sprayed with the aid of the spray device 1. For example, in this case, in a first step, first without a connection of the gas to the substrate, a dam from the fluid to be sprayed can be applied, which is subsequently sprayed with the fluid in a second step with the aid of the gas. The gas preferably has a twist on exit from the gas cap 42. For this purpose, the gas cap 42 on the inside and / or the dispensing needle 41 may be provided on the outside with a spiral contour. Furthermore, the dispensing needle 41 can be negative and the substrate be positive or vice versa electrically charged. As a result, a better spray pattern, a better edge sharpness and less blobbing are achieved. Because the volume flow of the fluid and the volume flow of the gas can be regulated independently of one another, a particularly large operating range for the spray device 1 results.

The Fig. 6 shows a further embodiment of a spraying device 1. The spraying device 1 comprises a first metering device 2 and a second metering device 47. The metering devices 2, 47 may be of identical or different construction. In particular, the metering devices 2, 47 can be constructed identical to the metering device 2 according to FIG Fig. 1 to 5 be. For example, the metering devices 2, 47 may be configured to volumetrically meter different amounts of two components of a fluid. The first metering device 2 is adapted to volumetrically meter a first component of the fluid and the second metering device 47 is adapted to meter a second component of the fluid. The fluid may be, for example, a two-component adhesive.

Each metering device 2, 47 has a pump housing 15. The pump housing 15 may be firmly connected to each other. Alternatively, the pump housing 15 may also be made of one piece material. In each pump housing 15, a stator 17 and a rotatable rotor 23 are accommodated in each case. The rotor 23 has a helical or helical outer geometry or outer contour. The stator 17 comprises a tubular outer part 18, which is received by means of a dowel pin 20 rotationally fixed in the pump housing 15. The stator 17 further comprises an elastomeric member 19 made of an elastomeric material. The elastomer part 19 has a helical or helical outer geometry or outer contour. The stator 17 is clamped axially between the pump housing 15 and an end piece 22 of the respective metering device 2, 47.

The spray device 1 further comprises a common spray device 34 with a spray head 40. The spray head 40 comprises a gas housing 35 which is fixedly connected to the end piece 22, for example screwed. On the gas casing 35, a gas supply pipe 38 for supplying a gas is provided. In the gas housing 35, a first fluid channel 48 and a second fluid channel 49 are further provided. Through the first fluid channel 48, the first component of the fluid and through the second fluid channel 49, the second component of the fluid is conveyed. The fluid channels 48, 49 also pass through a first connection plate 55 which connects the spray head 40 to the pump housings 15. The fluid channels 48, 49 meet at a mixing chamber 50 in which the first component of the fluid and the second component of the fluid mix with each other. The mixing chamber 50 is provided in a second connecting plate 73. In the mixing chamber 50, a static mixer may be provided. A static mixer is a fixture that achieves the desired mixing and dispersion effects by flowing the components of the fluid through rigid mixing elements. The energy required for mixing is provided by the metering devices 2, 47. The mixing chamber 50 is particularly suitable for mixing ratios of the components of 1: 1 to 1: 5.

The spray head 40 further comprises a gas cap 42 which is secured by means of a union nut 44 to the gas housing 35. The gas cap 42 has a central conical bore through which a dispensing needle 41 is passed. The dispensing needle 41, the connecting plate 55 is screwed. The dispensing needle 41 may extend in a longitudinal direction L _{1 of} the spray device 1 via the gas cap 42.

During operation of the spray device 1, the first component and the second component of the fluid are metered by the respective metering device 2, 47 and supplied to the mixing chamber 50. In the mixing chamber 50, the two components mix and are metered via the dispensing needle 41. The gas flows via the gas supply line 38 into the gas housing 35 and is via a gas channel 46 and a metering needle 41 annular circumferential gap 43 distributed. The gas flows around the metering needle 41 like a jacket and travels with the fluid for spraying.

The Fig. 7 shows a further embodiment of a spraying device 1. The spraying device 1 according to the Fig. 7 differs from the spray device 1 according to the Fig. 6 essentially in that the spray device 1 according to the Fig. 7 has no mixing chamber 50.

The dispensing needle 41 is here executed in several parts. The dispensing needle 41 comprises an inner part 51 with a central fluid channel 52, which is fluidically connected to the first fluid channel 48 and through which the first component of the fluid is conveyed. The dispensing needle 41 further comprises an outer part 53, which is attached to the inner part 51. Between the inner part 51 and the outer part 53, a fluid channel 54 is provided, which is fluidically connected to the second fluid channel 49 and through which the second component of the fluid is conveyed. The fluid channel 52 may be referred to as the first fluid channel of the dispensing needle 41 and the fluid channel 54 may be referred to as the second fluid channel of the dispensing needle 41. The fluid channel 54 surrounds the inner part 51 like a shell. That is, when dosing the components of the fluid they are not mixed but emerge as two components of the dispensing needle 41 on the front side. The mixing of the components takes place in that the components are swirled and mixed during the spraying with the aid of the gas.

The Fig. 8 shows a further embodiment of a spray device 1. The embodiment of the spray device 1 according to the Fig. 8 differs from the embodiment of the spray device 1 according to the Fig. 6 essentially in that a static mixer or a static mixing element 72 is provided instead of the mixing chamber 50 in the dispensing needle 41.

Between the gas housing 35 and the end piece 22, the connecting plate 55 for connecting the metering devices 2, 47 and an intermediate plate 56 is provided. The gas cap 42 is materialeinstückig formed with the gas housing 35. Screwed to the gas cap 42 is a tubular gas cap extension 57. The gas cap extension 57 may also be formed integrally with the gas cap 42. The dispensing needle 41 also has a tubular Dosiernadelverlängerung 58, in which a static mixer can be arranged. The dispensing needle 41 may protrude beyond the gas cap extension 57 in the longitudinal direction L ₁ . The two components are mixed together in the dispensing needle 41, in particular in the Dosiernadelverlängerung 58 and then sprayed.

The Fig. 9 shows a further embodiment of a spraying device 1. The spraying device 1 according to the Fig. 9 differs from the spray device 1 according to the Fig. 6 in that a mixing element 59 for dynamically mixing the first component of the fluid with the second component of the fluid is arranged in the mixing chamber 50.

The mixing element 59 is non-rotatably connected to a mixing element drive shaft 60. The mixing element drive shaft 60 can be driven, for example, by means of an electric motor. By using the rotatable mixing element 59, in particular mixing ratios of the components of the fluid of, for example, 1: 1 to 1: 100 can be achieved.

The 10 to 15 each show in a schematic sectional view of various embodiments of a spray device 1 with different spray heads 40. The embodiments of the spray head 40 according to the 10 to 15 is both for the spray device 1 according to the Fig. 1 to 5 , of the Fig. 6 , of the Fig. 7 , of the Fig. 8 as well as the Fig. 9 suitable.

The Fig. 10 shows an embodiment of the spray head 40, wherein the gas cap 42 has a tubular gas cap extension 61. A length of the gas cap extension 61 is arbitrary. The dispensing needle 41 has a dispensing needle extension 62 corresponding to the gas cap extension 61. The metering needle extension 62 can protrude beyond the gas cap extension 61 in the longitudinal direction L ₁ . The dispensing needle 41 is screwed into the end piece 22. Alternatively, the dispensing needle 41 may be integrally formed with the end piece 22 material. The spray head 40 according to the Fig. 10 is particularly suitable for applications in which only a small amount of space for spraying the fluid is available.

The Fig. 11 shows an embodiment of the spray head 40, in which the dispensing needle 41 is integrally formed with the end piece 22 material. Otherwise corresponds to the spray head 40 in the Fig. 1 to 5 shown spray head 40. The spray head 40 according to the Fig. 11 is particularly suitable to avoid dead spaces. For example, this is advantageous for precision in small doses.

The Fig. 12 shows an embodiment of the spray head 40, in which the dispensing needle 41 is designed as a disposable or disposable. In particular, the dispensing needle 41 is a disposable cannula used in medical technology. The dispensing needle 41 has a connecting body 63 made of a plastic material and a cannula 64, wherein the connecting body 63 can be injection-molded onto the cannula 64 in a plastic injection molding process or glued to it. The connection body 63 has an inner cone 65 into which an outer cone 66 of the end piece 22 can be inserted. The inner cone 65 and the outer cone 66 form a Luer-lock connection. Luer-Lock is a standardized connection system for medical tubing systems. As a result, the dispensing needle is particularly easy and quick to replace.

Between the inner cone 65 and the outer cone 66, a sealing element 67, in particular an O-ring may be arranged. The outer cone 66 is preferably formed integral with the end piece 22 material. The gas cap 42 is formed to surround the terminal body 63. In the gap 43, which is provided between the cannula 64 and the gas cap 42, vortex elements 69 are provided for swirling the gas. The vortex elements 69, the Gas cap 42 inside, for example, helical or helical rotate around to put the gas in a twist.

The Fig. 13 shows an embodiment of the spray head 40, wherein the gas cap 42 is adjustable. The embodiment of the spray head 40 according to the Fig. 13 differs from the embodiment of the spray head 40 according to the Fig. 12 in that a length-adjustable gas pipe 70 is provided on the gas cap 42. The gas pipe 70 may be connected to the gas cap 42, for example by means of a snap-in fitting. By adjusting the gas pipe 70, the exit angle of the fluid during the spraying thereof can be adjusted by adjusting the projection of the metering needle 41 via the gas pipe 70.

The Fig. 14 shows an embodiment of the spray head 40 with different swirl elements 69. The embodiment of the spray head 40 according to the Fig. 14 has an integrally formed with the end piece 22 dispensing needle 41, which protrudes beyond the gas cap 42. In the gap 43, various swirl elements 69 are provided for swirling the gas. The vortex elements 69 may be formed in one piece or in several parts. The vortex elements 69 may also have a twist. In particular, the swirl elements 69 are adapted to divert the gas helically.

The Fig. 15 shows an embodiment of the spray head 40 with a porous swirl element 69. The embodiment of the spray head 40 according to the Fig. 15 differs from the embodiment of the spray head the Fig. 14 essentially in that the entire gap 43 is filled with the porous swirl element 69. The vortex element 69 may be in one piece or in several parts. In particular, the vortex element 69 is made of a sintered ceramic or metal material. The gas flows through the vortex element 69. With the aid of the vortex element 69, the gas can be indeterminate, that is chaotic, swirling.

Although the present invention has been described with reference to embodiments, it is variously modifiable.

LIST OF REFERENCE NUMBERS

1

sprayer

2

metering

3

bearing housing

4

drive shaft

5

roller bearing

6

roller bearing

7

circlip

8th

claw clutch

9

seal housing

10

sealing device

11

sealing device

12

sealing device

13

fastener

14

sealing element

15

pump housing

16

sealing element

17

stator

18

outer part

19

elastomer part

20

dowel

21

paragraph

22

tail

23

rotor

24

flexshaft

25

supply port

26

vent

27

vent hole

28

dowel

29

Heating and / or cooling device

30

Heating and / or cooling element

31

Heating and / or cooling element

32

circuit board

33

plug

34

spraying

35

gas housing

36

fastener

37

sealing element

38

Gas supply line

39

Gas supply hole

40

spray nozzle

41

Dispense

42

gas cap

43

gap

44

Nut

45

knurling

46

gas channel

47

metering

48

fluid channel

49

fluid channel

50

mixing chamber

51

inner part

52

fluid channel

53

outer part

54

fluid channel

55

connecting plate

56

intermediate plate

57

Gas cap extension

58

Dosiernadelverlängerung

59

mixing element

60

Mixing element drive shaft

61

Gas cap extension

62

Dosiernadelfortsatz

63

connection body

64

cannula

65

inner cone

66

outer cone

67

sealing element

68

sealing element

69

vertebral element

70

gas pipe

71

accommodation space

72

mixing element

73

connecting plate

a

Got over

L ₁

longitudinal direction

M ₁

central axis

Claims (15)

Spray device (1) for spraying a fluid, comprising: a metering device (2), in particular an eccentric screw pump, for the volumetric metering of the fluid, and a spraying device (34) which is adapted to spray the metered by the metering device (2) fluid with the aid of a gas. A spraying apparatus according to claim 1, further comprising heating and / or cooling means (29) for heating or cooling the fluid to change its viscosity. Spray device according to claim 2, wherein the heating and / or cooling device in a pump housing (15) of the metering device (2) is arranged. A sprayer according to any of claims 1-3, further comprising a spray head (40) having a gas cap (42) and a dispensing needle (41) passed through the gas cap (42), the dispensing needle (41) being longitudinally (L ₁ ) of the spray device (1) protrudes beyond the gas cap (42). A spraying device according to claim 4, wherein a circumferential gap (43) for the gas is provided between the gas cap (42) and the metering needle (41). A spray device according to claim 4 or 5, wherein the spray head (40) comprises a swirl element (69) for swirling the gas. Spray device according to claim 6, wherein the swirl element (69) is made of a porous plastic, ceramic or metal material. Spray device according to one of claims 4 - 7, wherein the dispensing needle (41) with an end piece (22) of the metering device (2) is material integral or positively connected. Spray device according to one of claims 4 - 8, wherein the dispensing needle (41) and / or the gas cap (42) are adjustable in length. Spray device according to one of claims 1 - 9, wherein the metering device (2) is adapted for volumetric metering of a first component of the fluid and wherein the spraying device (1) comprises a further metering device (47), in particular an eccentric screw pump, for volumetric metering of a second component of the Fluids includes. A spraying apparatus according to claim 10, further comprising a mixing chamber (50) for mixing the first component of the fluid with the second component of the fluid prior to spraying the fluid by means of the spraying means (34). The spray device of claim 11, further comprising a mixing element (59) disposed in the mixing chamber (50) for dynamically mixing the first component of the fluid with the second component of the fluid. The spray device of claim 11, further comprising a static mixer disposed in the mixing chamber (50) for mixing the first component of the fluid with the second component of the fluid. A spraying device according to any one of claims 10 to 13, further comprising a spray head (40) having a dispensing needle (41) adapted to mix the first component of the fluid with the second component of the fluid. A spraying device according to claim 14, wherein the dispensing needle (41) comprises a static mixing element (72).

Images