WO2013023313A1

WO2013023313A1 - Method for spraying on adhesives

Info

Publication number: WO2013023313A1
Application number: PCT/CH2012/000186
Authority: WO
Inventors: Thomas Simmler
Original assignee: Alfa Klebstoffe Ag
Priority date: 2011-08-17
Filing date: 2012-08-14
Publication date: 2013-02-21
Also published as: EP2648851A1; PL2648851T3; EP2559491A1; EP2648851B1

Abstract

The invention relates to a method for spraying a one-component adhesive onto surfaces (21), which offers at least two modes, in which the one-component adhesive is either sprayed on its own or a one-component adhesive is sprayed jointly with an accelerator component. A device (1) for carrying out the method allows simple switching between the first and the second mode. In addition to a spraying arrangement for the one-component adhesive, the device (1) comprises an additional spraying arrangement for additional spraying of an accelerator component.

Description

Method of spraying adhesives

Technical area

The invention relates to a method for spraying a one-component adhesive on surfaces. The invention also relates to a spraying device for carrying out the method with a spraying device for spraying a one-component adhesive onto a surface. State of the art

One-component adhesives (1K adhesives) based on polychloroprene dispersions in aqueous solution have been used in the foam industry for about 20 years. For example, in the patent EP 0 624 634 these are extensively described. 1 K adhesives may u. A. be applied using 1 K spray guns, as described in US 2002/166902A. When bonding demanding objects, however, it may happen that the initial adhesion of these adhesives is insufficient.

A further development are the two-component adhesives (2K adhesives) based on polychloroprene. They have an improved initial adhesion, which is even comparable to the initial adhesion of solvent-based adhesives. However, it always requires both components, usually a dispersion and a coagulant, such as. As a saline solution or a dilute acid. The application of these adhesives is usually done via 2K spray guns. An example of such a spray gun can be seen from US 4,713,257A or DE 20 2005 018 206 U 1. However, 2-component adhesives have the disadvantage that technically complicated systems are necessary for their processing, which are also very expensive in terms of service and maintenance. It must be ensured that the mixing ratio between coagulant and adhesive component is constant. If the mixing ratio deviates too much from the target value, the adhesive does not show the desired properties and the bonding can not be carried out. The reason for this is the relatively high stability of the formulation; this is so stable that it shows no sufficient wet grip without coagulant. Only with an activator can the dispersion be destabilized to the extent that a setting process is triggered.

Thus, US Pat. No. 5,419,491 A discloses a 2K spray gun with which an adhesive and an accelerator are sprayed together in a constant ratio to one another. In this case, the actuating mechanism is designed so that shortly before the spraying of the main component even the additional component can escape, so as to ensure that the main component aliein is never sprayed on separate. Plants for applying two components to a surface are also known from other technical fields, for example from the field of impregnation of material surfaces. DE 10 2009 052654 A1 describes such a device which can spray a preservative and an additional hardener. In three embodiments, only a combined spraying of the two components is possible. However, it is not intended to spray the components individually. In a fourth embodiment, it is provided to spray first the preservative and shortly thereafter the additional hardener. For this purpose, two application elements are provided, wherein from the first application element the preservative and from the second application element of the hardener is sprayed. The object to be sprayed is transported by a conveyor belt from the first to the second application element. The hardener is sprayed flat to the same extent as the preservative.

Overall, a system is sought that combines the advantages of both adhesives - 1K and 2K adhesive. Presentation of the invention

It is an object of the invention to provide a method for spraying a one-component adhesive on surfaces which can be glued to variously difficult-to-bond regions without resulting in increased material consumption and unnecessarily prolonged setting times. Another object is to provide a device suitable for carrying out the method.

The solution of the problem is defined by the features of claim 1. According to the invention, this is a method for spraying a one-component adhesive on surfaces with two defined modes, between which is switched. In the first mode, only a 1K adhesive is sprayed alone. In the second mode, in addition to the 1K adhesive, an accelerator component for the 1K adhesive is also sprayed, with a beam of the 1K adhesive and a beam of the accelerator component mixing together. On the sprayed surface can then at least a portion of the one-component adhesive alone and at least a portion of the one-component adhesive combined with accelerator component are generated.

A method according to the invention, in which it is possible to spray on an accelerator component only when required, offers several advantages: First, the initial adhesion of the adhesive is increased by the accelerator component, so that sites which are difficult to bond can nevertheless be glued reliably. Targeted application to these demanding areas minimizes the overall consumption of the accelerator component, since it is not necessary to apply it to the entire surface to be bonded. On easy-to-bond surfaces, there is no need for an accelerator. Due to the economical use of the accelerator component less water, which serves as a solvent for the accelerator component, applied to the easy-to-bond sites. These areas can then dry completely faster, as they will not be soaked unnecessarily. Overall, with this method, an adhesive process in which different difficult-to-bond pieces are processed, be optimized in terms of material costs, drying time and processing time.

1-K adhesives are characterized by the fact that they have an initial adhesion, ie they have a certain adhesive power of their own, without the need for an auxiliary agent. The adhesive power of 1K adhesives is only slightly reduced compared to the adhesive power of 2K adhesives. However, this difference can already be sufficient to no longer be able to connect surfaces that are difficult to bond sufficiently well. In particular, the bonding of elements which make different demands on the adhesive on the same workpiece is difficult to carry out with a 1K adhesive. So z. For example, a seat cushion for a sofa on a large area and a small side surface. The seat can be easily bonded to other substrates with virtually no tension. The side surfaces, however, represent a voltage bonding for the substrates to be bonded, in which a higher initial adhesion is desired. Similar problems are encountered when gluing sofa or chair frames made of wood with flexible foams; Also there occur high restoring forces, which must be absorbed with the adhesive. An accelerator component increases the adhesive force of a 1K adhesive. The accelerator component destabilizes the provided adhesive and thus accelerates the coagulation. Thus, two components are applied to the hard-to-bond surfaces. In contrast to a 2K adhesive, however, the one component itself already has an adhesive power. The accelerator component is not supplied permanently, but only when needed. In contrast, when using 2-adhesives, the constant supply of both components is necessary.

When carrying out the method, it is not absolutely necessary for both areas to be present on each individual object. Are z. If, for example, several differently shaped or differently processed objects are sprayed one behind the other, an advantage of the method is that the several objects are treated differently in one workflow. While some objects are only sprayed with the 1K system, others are provided with the 1K Plus system. It can only arise on some of these objects both areas. Overall, the objects can be sprayed individually as part of the process.

Optional third mode:

In a preferred variant, the method offers a third mode in addition to the previously described first and second modes. In the third mode, the accelerator component is sprayed alone. The additional third mode thus offers even more flexibility in the process. It is possible for the user to sprinkle only with the accelerating component in places which he classifies as difficult to bond in the first mode after application of the 1K adhesive. It is not necessary to apply in this case again the 1 K adhesive, and thus accept a higher material consumption and longer drying times. Overall, it is therefore possible to switch between the first, second and third modes.

But it can also be dispensed with a third mode, if the overall process is easier to do so.

Proportion of the accelerator component: A process of applying a 1K adhesive with an accelerator component (1K-plus system) provides greater production safety because the exact mixing ratio of the two components is not critical. Usually, 1K-plus systems have some tolerance in terms of mixing ratio. The proportion of the accelerator component is 2 to 25 wt .-%, preferably 5 to 15 wt .-%, particularly preferably 8 to 12 wt .-%.

Preferably, the switching between the first mode and the second mode can be done by operating a single control element. Such ease of use facilitates the process and so hardly allows errors in the execution. It may be that both the 1 K adhesive, as well as the accelerator component are controlled via a common operating element with an off position and two operating positions. If the control element is in the first operating position, the 1K adhesive is supplied (first mode). When the control is in the second operating position, the 1K adhesive and the accelerator component are supplied (second mode).

But it is also possible to control both components via two control elements. So z. B. the 1 K adhesive controlled by a first control element, while the accelerator component is controlled via a second control element. In order to be able to supply the accelerator component, the second operating element is additionally actuated when carrying out this method.

A method with three modes is preferably controlled by the actuation of two operating elements, wherein here too the flow of each component can be triggered or stopped with a control element. In this case, the actuation of the first operating element corresponds to the first mode. The actuation of the second control element corresponds to the third mode. The simultaneous operation of both controls corresponds to the application of the 1K adhesive together with the accelerator component and thus the second mode.

The 1K adhesive is preferably a dispersion adhesive. Here are in the water as a mobile phase adhesive components dispersed. By applying the dispersion to the surface to be bonded, the dispersant can escape; the Dispersion breaks. The concentration of the adhesive particles increases, and a layer is formed which connects the elements to be bonded together. Dispersion adhesives are safer to use due to the use of water as a solvent as there are no flammable or explosive solvents. In addition, no solvent vapors are released which are hazardous to health.

The dispersion adhesive is preferably based on polychloroprene. Polychloroprene has a relatively high initial adhesion and is easily mixed with other substances, eg. B. modifiable with fillers.

In a preferred variant, the accelerator component is an aqueous salt solution. Optionally, the accelerator component may also be a dilute acid.

sprayers:

A sprayer suitable for spraying an adhesive on surfaces according to the described method comprises a spraying device for spraying a one-component adhesive onto a surface. Further, an auxiliary sprayer is provided for additionally spraying an accelerator component for the one-component adhesive. There is a first actuating device for the spray device and a second actuating device for the additional spray device. The two actuating devices are designed such that it is possible to switch between the first and the second mode. The spraying device is designed such that in the second mode the one-component adhesive and the accelerator component mix outside the device. Thus, by spraying the sprayer on the surface, at least a portion of the one-component adhesive alone and at least a portion of the one-component adhesive may be combined with accelerator component.

Two nozzles:

The spray device comprises at least a first material guide for the 1K adhesive, which can be opened or closed via a first valve. This first material guide is arranged within a housing. The material is about a supplied to the first material line. The valve is controlled by a first actuator, which is located on the outside of the housing. If the valve is open, the 1 K adhesive is sprayed through a spray nozzle. In addition, the sprayer on a Zusatzsprüheinrichtung with a second material guide and a second valve. This second material guide is provided for the accelerator component. The accelerator component is supplied via a second material line and sprayed via a secondary nozzle. The spray device is designed such that the 1 K adhesive can be sprayed independently of the accelerator component.

A sprayer designed in this way allows a flexible use of the accelerator component and thus a material-sparing type of bonding of materials which have areas to be bonded differently.

In general, the sprayer according to the invention can also be used to apply a 1K adhesive alone. So it is not necessary to provide different spraying devices for the spraying of a 1 K-adhesive and a 1 K-plus-system. Especially for a casual user, this additional versatility of the sprayer is an advantage.

1 control element:

Preferably, the sprayer on a single common control element, with which is switched between the first and the second mode. A single control allows for very easy handling of the sprayer and minimizes potential design errors. The one control element has a rest position and two operating positions. In the rest position no material is sprayed. If the operating element is in the first operating position, only the spraying device is actuated and the 1 K adhesive is supplied. If the operating element is in the second operating position, then both the spraying device and the auxiliary spraying device are actuated and the 1K adhesive and the accelerator component are supplied.

Under a control is understood in this context, a technical means which can control the supply of a material, ie z. B. opens a valve. It may be z. B. to a bracket, lever, tilt, rocker, slide switch, knob or push button act.

Preferably, the one control element is a lever with a rest position and two operating positions. When the lever is pulled to the first operating position, the first mode of the method is executed. When the lever is pulled more to the second operating position, the second mode is executed.

The operating element can be designed in such a way that it has to be constantly held in the desired position by a user. But it can also be provided that the one and / or the other position can be fixed by z. B. is executed latched.

2 operating elements:

In another embodiment of the spray device, it is provided that each component is controlled via its own control element. The sprayer has two controls that are operated independently. In a method with two modes z. B. the 1 K adhesive controlled by a first control element, while the accelerator component is controlled via a second control element. In order to be able to supply the accelerator component, the second operating element is additionally actuated when carrying out this method. A method with three modes is preferably controlled by the actuation of two operating elements, wherein here too the flow of each component can be triggered or stopped with a control element. In this case, the actuation of the first operating element corresponds to the first mode. The actuation of the second control element corresponds to the third mode. Depending on the embodiment of the sprayer, it may be necessary to also operate the first control to switch to the third mode. Thus, the first control element can be brought into a pre-position in which only compressed air, but no 1 K adhesive is sprayed. In the compressed air jet then the accelerator component can be injected. The simultaneous operation of both controls corresponds to the application of the 1K adhesive together with the accelerator component and thus the second mode. The controls may be z. B. to handle, levers, tilt, rocker, slide switch, knobs and / or push buttons act. Two controls on a sprayer can be the same or different. Preferably, the first operating element is designed as a lever, while the second operating element is a push button. The push button can be preferably with a finger, z. B. operate the thumb.

Optionally, a fixing possibility for the first and / or the second control element can be provided, which is also operated with only one finger. A lever can z. B. are fixed by a bolt, which locks the lever in the activated state and leaves the lever in the deactivated state to move freely.

The sprayer can also be constructed such that a combination of both controls is constructed by a simple operation. Through such a coupling, the accelerator component always flows out as soon as the first control element for the 1 K adhesive is actuated. On / off switch:

Preferably, the second control over which the addition of the accelerator component is controlled can be set in two positions: on and off. An on / off switch has a simple design and is therefore inexpensive.

But it is also possible to provide a second control element, which has more than two positions, z. B. with two or more stages in which the accelerator component varies in strength, d. H. is added in different amounts to 1 K adhesive. It is also conceivable to provide a second operating element, which makes it possible to adjust the amount of the accelerator component continuously.

External Mixing: In an advantageous embodiment, the spraying device is designed in such a way that the 1 K adhesive and the accelerator component mix outside the spraying device. The atomizing nozzle and the sub-nozzle are aligned with each other at the exit of the device such that a beam of the 1 K adhesive and the accelerator component mix with each other. Preferably, the accelerator component is injected into the main jet of the 1K adhesive.

A mixing of the two components outside of the sprayer allows a simpler structure of the device, since it can be dispensed with a mixing chamber in its interior. In addition, no adhesive mixture is produced with an accelerated setting behavior within the sprayer. This simplifies or even eliminates time-consuming and material-consuming cleaning procedures.

But it can u. U. be advantageous to mix special recipes within the sprayer when z. B. one of the substances is air or oxygen sensitive. However, a sprayer provided for this purpose no longer has the stated advantages of a spraying device with external mixing.

Surface nozzle:

It is particularly favorable if the atomizer nozzle is designed as a broad jet nozzle. For this purpose, two air ducts are arranged on the air head laterally of the atomizer nozzle such that the atomizer nozzle lies on a connecting line between the two air ducts. The atomizer nozzle itself produces a round jet. Through the air from the two air channels, the material to be sprayed is applied in a broad jet.

But there are also other types of nozzles conceivable, such. B. round jet nozzles.

Sub-nozzle arrangement: The sub-nozzle is preferably an injection nozzle. The injector via which the accelerator component is added is mounted laterally on the atomizer nozzle. In a preferred arrangement, the injection nozzle is oriented in such a way that the jet of the accelerator component is sprayed as perpendicular as possible to the spray axis of the atomizer nozzle, ie perpendicular to the broad spray cone. In order to come as close as possible to the preferred angle of 90 ° to the broad jet spray cone, the injection nozzle is preferably provided directly in the region of a lateral air duct on the air head, ie the injection nozzle is a fixed part of the air head. The injection nozzle can be mounted in the region of an air duct. For this purpose, the air cap in the region of an air duct on a front extension, which provides space for an injection nozzle. This arrangement makes it possible to inject the accelerator component at an angle of 90 ° in the broad-jet spray cone of 1 K adhesive. However, this extension on the airhead is a disadvantage because it can be easily damaged when handling the sprayer or broken completely.

Optionally, the injector may be provided directly adjacent to an air passage. The injection angle is then slightly lower than 90 °, it is z. B. in a range of 80 ° - 90 °. The angle is reasonably good for effective mixing, while the air head has no exposed area that is easily damaged.

Alternatively, the injection nozzle may be present as a separate component that is flexibly mounted on the commercially available air head of a spray nozzle. Also, a separate injection nozzle is aligned so that its beam is sprayed as possible at an angle of 90 ° in the broad jet spray cone of 1 K adhesive. Depending on the injection nozzle but requires more or less space, so that the angle is actually between 30 ° and 80 °.

The injector may also be mounted at other angles. However, then a complete mixing of the two components is not guaranteed. If the injection nozzle is oriented in such a way that the accelerator component is injected in the plane of the spray jet, mixing of the two components takes place only to a limited extent. Under certain circumstances, however, the construction of the air head or a space-consuming injection nozzle does not allow a more favorable arrangement.

Spray gun:

In the preferred embodiment, the sprayer is designed in the manner of a hand-operated spray gun. Their mode of action can be explained as follows: The liquid to be sprayed is atomized by means of a pressure difference into small drops. The droplets then hit a surface to be sprayed, resulting in a surface film. The material can be fed via a flow cup, suction cup or pressure lines. The pressure difference will vary depending on the construction of the gun generates and identifies the respective spraying process. Decisive is also a corresponding nozzle set, consisting of nozzle needle, fluid nozzle and matching air cap. Overall, therefore, the amount of material, the amount of air and the type of spray can be adjusted. Spray guns are used to apply paints, varnishes and adhesives. Such a sprayer is easy to handle and produces even layers of the substances to be sprayed.

But it is also possible that the sprayer is designed as a sprayer, which is controlled electronically or pneumatically. Since the device is not hand-operated, it does not have to have a specific outer shape, which makes operation easier. The necessary for the spraying elements can also be present without housing.

1 K Plus Spray Gun:

In particular, the sprayer is a commercially available 1K air operated gun with additional equipment. Thus, a further supply of material for the accelerator component, an operating element for switching on and off the accelerator supply, and an injection nozzle for the accelerator are provided on the outside of the spray gun.

Flow control:

The accelerator component is directed under pressure into the additional fluid supply. The pressure is preset. Optionally, a flow regulator can be arranged on the additional material guide. Thus, it is possible to make a fine adjustment of the accelerator component on the spray gun.

But it can also be dispensed with a flow regulator. The amount of the accelerator component is then regulated solely by presetting the pressure. A spray gun without additional flow regulator is cheaper to manufacture.

In principle, however, the accelerator component can also be conducted via a free-flow system into the additional material supply, wherein a supply of compressed air or a pump can be dispensed with. The accelerator component is in one appropriate storage vessel stored higher and directed solely by gravity in the additional material supply.

One-hand sprayers:

The spray gun is designed to have one-handed controls. The spraying process is carried out by one-handed operations. So it is possible to operate simultaneously with one hand, the lever for spraying the 1 K adhesive, as well as a switch or button for releasing the supply of the accelerator component, preferably with a finger, z. B. the thumb to use. From the following detailed description and the totality of the claims, further advantageous embodiments and feature combinations of the invention result.

Brief description of the drawings

The drawings used to explain the embodiment show: Fig. 1 a-c the possible modes 1, 2 and 3 in which spraying can be carried out;

Fig. 2a, b an object with different difficulty to be bonded points before and after the spraying process according to the method;

Fig. 3 is a commercial 1 K spray gun;

Fig. 4a, b a material nozzle in front and side view; Fig. 5 front view of a spray nozzle with air cap;

6 shows a first inventive 1 K-plus spray gun in one

Embodiment with a control element;

7 shows a second inventive 1 K-plus spray gun in one

Embodiment with two controls; Fig. 8a-d variants of a spray nozzle with injection nozzle

9 is a side view of a spray nozzle with injection nozzle.

Basically, the same parts are provided with the same reference numerals in the figures. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A spraying device 1 is shown schematically in FIGS. 1 a-c, with which the method according to the invention can be carried out. The sprayer 1 allows a simple switching between the first and second modes or third mode, if provided. The spray device 1 consists of a housing 2, which has two operating elements, which are designed as first and second switches 3 and 4. In this case, the first valve 5 of the first material guide 6 can be actuated via the first switch 3. Accordingly, with the second switch 4, the second valve 7 of the second material guide 8 can be controlled. At the end of the first material guide 6 there is an atomizer nozzle 9. At the end of the second material guide 8, the auxiliary nozzle 10 is arranged. A switch is understood to mean a functional element which has two clearly defined positions. There is no stable position between these unique positions. In the ideal case, the switch abruptly changes the operating mode of the device, comparable to an electrical toggle switch. In other words, the switch has two intrinsically stable states, one of which defines the state "valve open" and the other the state "valve closed".

In Fig. 1 a, the spray device 1 is shown in the first mode. By actuating the first switch 3, the first valve 5 is opened, and the 1 K adhesive is passed into the first material guide 6. At the end of the first material guide 6, the 1K adhesive exits through the atomizer nozzle 9 in the form of a first jet 11. At the same time, the second switch 4 is not actuated, so that the second valve 7 remains closed and no material is passed through the second material guide 8. Fig. 1 b shows the same sprayer 1 in the second mode. In addition to the opened first valve 5, the second valve 7 is also opened by actuating the second switch 4. While the 1 K adhesive flows through the first material guide 6 and emerges radially at its end through the atomizer nozzle 9, the accelerator component is passed through the second material guide 8. It emerges at the end of the second material guide 8 through the auxiliary nozzle 10 in the form of a second jet 12. The atomizing nozzle 9 and the auxiliary nozzle 10 are arranged such that the 1 K adhesive and the accelerator component mix outside with each other.

The optional third mode is shown in FIG. 1 c. In the third mode, only the accelerator component is sprayed. For this purpose, only the second switch 4 is actuated, so that the second valve 7 is opened and the accelerator component passes through the second material guide 8 to the sub-nozzle 10. The first switch 3 is not actuated; no 1 K adhesive is sprayed.

FIG. 2 a shows an object 20 with regions which are difficult to bond differently. The surfaces 21 of the object 20 are easy to bond, the use of a 1 K adhesive with a sufficient adhesive force is completely sufficient in these areas. In contrast, the areas of the edges 22 and corners 23 are demanding. In these areas, it may be necessary to use an accelerator component in order to increase the initial force of the adhesive.

2b shows the object 20 with areas of different difficulty to be bonded after application of the adhesive and, if appropriate, the accelerator component according to the method described. The surfaces were sprayed in the first mode, on top of which is a 1K layer 24 of the 1K adhesive. The edges and corners, however, have been sprayed in the second mode. So they have a 1 K-plus layer 25, consisting of the 1 K adhesive and the accelerator component. It is also possible that the areas of the edges and corners were first sprayed in the first mode exclusively with the 1K adhesive and afterwards with the accelerator component in the third mode. This two-stage application also leads to the 1 K-plus layer 25. The different layers 24 and 25 are not necessarily sharply delimited from each other, the transition can also be fluid. Likewise, the Extension of the 1 K plus layer 25 vary, it is not necessarily limited to a certain distance from the edge or corner.

Fig. 3 shows schematically a commercially available 1 K spray gun 30, with which, however, it is not possible to turn on if necessary, another component. In general, the 1 K spray gun 30 has a housing 31 with a spray head 32 and a handle 33. Often, the spray gun 30 has a hook 34 for hanging.

Through the spray gun passes through a compressed air line 35. At its end on the handle 33 is an air port 36, on the z. B. a compressor is connected. In the compressed air line is a slide valve 37. The compressed air line 35 opens in the front region 38 of the spray gun 30. The compressed air line 35 is divided into an inner region 39 and an outer region

40 of the compressed air line 35.

In addition, a material supply 41 is provided in the front region 38 of the spray gun 30. The material to be sprayed can be supplied via a pressure line or a suction cup and connected via the material connection 42. The material feed

41 opens below the compressed air line 35. Through the material supply 41, a material needle 43 runs.

In the front region 38 of the spray gun 30, an air distributor ring 44 is placed in front of the compressed air line 35 and the material supply 38. This distributes the compressed air so that it continues to flow in a wider cone, the compressed air from the inner region 39 and the outer region 40 of the compressed air line 35 is separated from each other.

In front of the air distributor ring 44, a material nozzle 45 is mounted. This is constructed in three parts. The inner part of the material nozzle 45 is an extension of the material supply 41 and is screwed directly onto it. It is pulled out towards the front 46 and has an opening in the middle, which is dimensioned such that it can be closed by the material needle 43. Around the inner part of the material nozzle, a first ring 47 is arranged from air ducts. Farther outside is a second ring 48 from air ducts. The first ring 47 is connected to the inner portion 39 of Compressed air line 35 is connected, while the second ring 48 communicates from air channels with the outer region 40 of the compressed air line 35.

Before the material nozzle 45, an air head 49 is set and fixed with an air head nut 50 on the housing 31 of the spray gun 30. This air head 49 has in the middle a round opening 51, in the extended tip 46 of the material nozzle 45 projects. The opening 51 is formed significantly larger than the tip 46 of the material nozzle 45 and forms an outlet for the compressed air. The portion of the compressed air, which is passed via the first ring 47 from air channels of the material nozzle 45, flows through this opening 51, and can entrain the material, which may be located at the tip 46. Furthermore, the air head 49 has lateral air channels 52 which are located on two attachments 53. About these air channels 52, the shape of the spray is designed. Through these air channels 52, the compressed air can flow, which is passed through the second ring 48 from air channels of the material nozzle 45.

The spray gun 30 is actuated via the trigger lever 60. The trigger lever 60 is pulled to an operating position. First, the pre-air is opened, d. H. it is the valve 37 of the compressed air line 35 is actuated. At the air head 49 exits from the opening 51 and possibly from the air channels 52 an air jet. Subsequently, the material needle 43 is withdrawn, whereby the material to be sprayed passes into the nozzle. The closing takes place in reverse order. It is possible to hold the trigger lever 60 in an intermediate position, so that only compressed air is passed through the gun 30.

At the spray gun 30 three basic settings can be made. On the one hand, the quantity of atomizing air can be determined by adjusting the air volume regulation 67 via the air quantity regulation 61. Upon actuation of the trigger lever 60, the cone of the valve 37 is opened. By the valve spring 62, the cone of the valve 37 is returned when releasing the trigger lever 60. Furthermore, the amount of material to be sprayed can be adjusted. By adjusting the needle spring 63 by means of the material adjustment 64 it is determined how far the material needle 43 is pushed back out of the tip 46 of the material nozzle 45, and how much material can flow out through it. Finally, via the control screw 65, the shape of the spray jet can be determined, since in this way the amount of air flowing into the outer ring 48 of the air channels at the material nozzle 45 and then into the Air passages 52 of the air cap 49 flows, is regulated. If the outer region 40 of the compressed air line 35 is completely closed with the cone 66, no compressed air can flow into the channels 52 of the air cap 49; the material is sprayed in a round jet. If the cone 66 is withdrawn, then compressed air flows through the channels 52 of the air cap 49. The spray jet which emerges in a round manner can thus be delimited laterally and brought into the form of a broad jet.

Fig. 4a, b show a material nozzle 45 in the front and in the side view. The central tip 46 of the fluid nozzle 45 is extended to the front and has a material opening 80. Through the material opening 80, the material to be sprayed emerges when the material needle 43, which lies in the material channel 81 of the material nozzle, is withdrawn.

Fig. 5 shows the basic structure of a spray nozzle 82 in the front view. The air head 49 has an opening 51 in the middle. Through this opening, the tip 46 of the material nozzle 45 can be seen with the material opening 80. Directly adjacent to the opening 51, two overpressure openings 83 are provided. Furthermore, the side 51 of the opening 51, two essays 53 having air channels 52, which are directed in the area in front of the opening 51. When material emerges from the material opening 80, it is sprayed by the air from the opening 51 in an omnidirectional jet. By the air from the air channels 52 of the circular beam is bounded on the sides and thus formed into a broad jet with a spray axis 84.

FIG. 6 shows a first inventive 1 K-plus spray gun 100, with which a 1 K adhesive and optionally an accelerator component can be sprayed. The 1 K-plus spray gun 100 corresponds to the 1 K spray gun 30 with additional elements. Thus, in addition to the outside of the housing 31 there is a second material supply 101 for the accelerator component, which opens into the injection nozzle 102. The injection nozzle is mounted in the region of the air head 49. In the second material supply 101 there is a valve 103, via which the flow of the accelerator component can be controlled.

The 1 K-plus spray gun 100 is actuated via the trigger lever 60. In contrast to the 1 K spray gun 30, the trigger lever 60 has a second operating position. Will the Trigger lever 60 brought into the first operating position described above, first the compressed air and then enter the material in the nozzle. In addition, the trigger lever 60 can be brought into a second operating position in which it is pulled even more to the handle 33. Thereby, the push button 104 is actuated, which communicates with the valve 103. Upon actuation of the push button 104, the valve 103 is opened, and the accelerator component can pass through the second material supply 101 to the injection nozzle 102, from where it is then sprayed into the main jet of the 1K adhesive.

The entire operation of the first inventive 1 K-plus spray gun 100 is done with one hand; For example, the 1K-plus spray gun 100 is held in one hand and the lever 60 is held with one finger of this hand, e.g. B. the index finger or the middle finger, in which he is pulled in the direction of the handle 33. Spraying the 1K adhesive by operating the lever in the first operating position corresponds to the first mode. The joint spraying of the 1K adhesive and the accelerator component by operating the lever in the second operating position corresponds to the second mode.

It should be noted that in this embodiment, the amount of the 1K adhesive is increased upon switching from the first mode to the second mode. Due to the stronger pulling of the trigger lever 60 to the handle 33, the material needle 43 is further retracted, thus providing more adhesive available.

FIG. 7 shows a second inventive 1 K-plus spray gun 200 with which a 1 K adhesive and optionally an accelerator component can be sprayed, wherein two control elements, namely lever 60 and push button 201, are provided for switching between the modes. The 1 K-Plus spray gun 200 corresponds in its internal structure to the commercially available 1 K spray gun 30 with additional elements. The spraying of the 1K adhesive is controlled with the lever 60 according to the principle described above.

In addition, on the outside of the housing 31 there is a second material supply 202 for the accelerator component. It opens into the injection nozzle 203, which in the region of Air head 49 is attached. The second material supply 202 passes through an additional housing 204, which is attached to the trigger lever 60.

In the second material supply 202 is a valve 205, which is controlled by means of the push button 201, which is located on the additional housing 204. The flow of the accelerator component can thus be switched on or off by pressing the push button 201. When the valve 205 is opened, the accelerator component flows into the further section of the second material supply 202, through a flow regulator 206 to the injection nozzle 203. While the trigger lever 60 is operated again with the index finger, the push button 201 is applied such that it z. B. can be operated with the thumb. Trigger lever 60 and push button 201 can be operated with the same hand. By operating the trigger lever 60 is sprayed in the first mode. By additionally pressing the push button 201 one switches to the second mode. In order to spray only the accelerator component in the third mode, the trigger 60 must be brought into the pre-position in which only compressed air flows out, but no material from the material nozzle 45 occurs. By simultaneously pressing the push button 201, the accelerator component is injected into the air cone and thus sprayed exclusively the accelerator component.

8a, b each show a spray nozzle 82 with an injection nozzle 102. In FIG. 8a, the injection nozzle 102 is mounted at an angle α = 60 ° to the spray axis 84. This orientation of the injection nozzle 102 is a variant that can be implemented particularly technically simple. It forms a compromise between the preferred angle of 90 ° and the space requirement of the injection nozzle 102. In contrast, in Fig. 8b, the injection nozzle 102 is provided at an angle ß = 0 ° to the spray axis 84. This angle is unfavorable, since such a mixing of the two components takes place only moderately. Fig. 8c, d show spray nozzles, in which an injection nozzle is integrated in the air head of the atomizer nozzle. Thus, in Fig. 8c an atomizer nozzle 301 is shown having an air cap 302 which includes a conventional cap 53 with two air channels 52 and a modified cap 303. This cap is larger and has two air channels 52 in addition to the compressed air an opening 304, which can be used as an injection nozzle. As a result, an injection angle of γ = 80 ° can be realized. Alternatively, an attachment may be made higher than usual, such as the modified attachment 305 of the atomizing nozzle 306 in Fig. 8d. The higher attachment provides enough space to provide an additional opening 307 above the air channels 52, which may then serve as the accelerator component injector. In this case, the accelerator component can be injected at the preferred angle of δ = 90 ° into the broad jet spray cone of the 1K adhesive. However, such a protruding essay is more susceptible to damage.

FIG. 9 shows the arrangement of the atomizing nozzle 82 with an injection nozzle 102 at an angle of 45 ° to the spray axis 84 in a side view. The angle ε, which occupy the rays of the two components to each other, is 30 °. In principle, the angle ε should be less than 45 °.

The abovementioned exemplary embodiments are to be understood merely as illustrative examples, which can be modified as desired within the scope of the invention.

When spraying the accelerator component in the third mode, it may be necessary to operate both controls. So z. B. via a first switch only the compressed air are activated, but no material flow. Subsequently, the accelerator component can be injected into the air jet and swirled there.

Among the objects to be sprayed are in particular upholstered furniture such as chairs, armchairs, sofas and corresponding cushions.

The sprayers can basically have different housing shapes, as spray guns. In particular, hangers or handles can be designed differently or completely omitted.

Optionally, other atomizing nozzles can be used as wide jet nozzles, z. B. round jet nozzles.

The design of the controls may vary. So levers, buttons and / or knobs may be provided except levers and snaps. The materials to be sprayed in storage containers z. B. present in flow or suction cups, but they can also be passed through pipes from larger tanks in the sprayer.

The arrangement of the material supply can also be configured differently, so the material can also be supplied from above or from the side.

Optionally, a spray gun with only one control element is designed such that the amount of adhesive remains constant when switching between the first and second modes. For this purpose, the further retraction of the material needle 43 during further pulling the trigger must be prevented, z. B. by a telescopic structure of the material needle or by a pulling device with a spring.

In summary, it should be noted that a method is provided which facilitates the spraying of objects with suitable adhesive. For simple sections, a sufficiently good 1K adhesive is applied to save material. For more demanding locations, the same 1K adhesive can be used in combination with an accelerator component. The switching between these and possibly other modes can be performed by a simple action with only one hand.

Claims

claims

A method of spraying a one-component adhesive on surfaces (21), characterized in that in addition to a first mode in which the one-component adhesive alone is sprayed, a second mode is used in which, in addition to the one-component Glue an accelerator component for the one-component adhesive is sprayed, wherein a beam of the one-component adhesive and a beam of the accelerator component mix with each other, and that is switched between the first and second mode, so that on the surface at least a portion of Ein- Component adhesive (24) alone and at least a portion of the one-component adhesive combined with accelerator component (25) can be generated.

2. The method according to claim 1, characterized in that in addition a third mode is used, in which only the accelerator component is sprayed, being switched between the first, second and third mode.

3. The method according to any one of claims 1 - 2, characterized in that the proportion of the accelerator component during spraying in the second mode at 2 - 25 wt .-%, preferably at 5 - 15 wt .-%, particularly preferably at 8 - 12 wt .-% lies.

4. Apparatus (1) for carrying out the method of claim 1, comprising a) a spraying device for spraying a one-component adhesive onto a surface (21), b) an additional spraying device for additionally spraying an accelerator component for the one-component adhesive , c) wherein a first actuating device (3) for the spraying device and a second actuating device (4) for the additional spraying device are present, and d) wherein the device is designed such that mix the one-component adhesive and the accelerator component outside the device, characterized in that e) the first and second actuating device are designed such that can be switched between the first and second modes, so at least one region of the one-component adhesive (24) alone and at least one region of the one-component adhesive combined with the accelerator component (25) can be produced on the surface.

5. The device according to claim 4, characterized in that the spray device comprises a spray nozzle (82) for the one-component adhesive and the auxiliary spray device an injection nozzle (102) for the accelerator component.

6. Apparatus according to claim 5, characterized in that a common operating element (60) for the first and the second actuating device is present, which has at least two operating positions, wherein a first operating position, only the spray device and a second operating position both the spray device and the Additional spraying device actuated.

7. The device according to claim 5, characterized in that the spraying of the one-component adhesive via a first operating element (60) and the spraying of the accelerator component via a second operating element (201) is triggered, and the two operating elements are independent of each other.

8. Apparatus according to claim 7, characterized in that the second operating element has two positions - off and on - has.

9. Device according to one of claims 5 - 8, characterized in that the

Atomizer nozzle (82) and the injection nozzle (102) on the output side of the device are aligned with each other so that a beam of the one-component adhesive and a beam of the accelerator component mix with each other.

10. Device according to one of claims 4 - 9, characterized in that the

Atomizer nozzle is a broad jet nozzle, in which there are two air channels adjacent to the atomizer element, which form the beam.

1 1. Device according to one of claims 4 - 10, characterized in that the

Injection nozzle (102) is arranged in an angular range between 30 ° and 90 °, preferably at an angle of 90 ° to the spray axis of the atomizer nozzle.

12. Device according to one of claims 4 - 1 1, characterized in that it is designed in the manner of a compressed air-operated spray gun (30).

13. The apparatus according to claim 12, characterized in that it is designed as a compressed air-driven one-component spray gun (200) having an injection nozzle (203), an additional material guide (202) and an operating element (201).

14. The apparatus according to claim 13, characterized in that there is a flow regulator (206) on the additional material guide.

15. Device according to one of claims 4 - 14, characterized in that the

Operating elements (60, 201) are arranged such that they can be operated with one hand.