DE20305103U1 - Spray head for two component lacquers has three mixing chambers connected by nozzles, producing progressively finer spray - Google Patents

Abstract

The spray head for spraying two component lacquers has two channels passing though it which are connected to the main canister, holding lacquer and a smaller canister inside the main canister which contains hardener. Both channels terminate in a premixing chamber (1). Mixture passes from this through a nozzle (2) into a second chamber where a finer spray is produced, then through a second nozzle (4) into a third chamber, producing a still finer spray, after which it is sprayed out through several nozzles (6).

Description

······ t· ·· »· .. Spray head for paint spray

Colux GmbH, W. v. Siemens-Str. 12, 78224 Singen

Two-component paint has been filled into aerosol cans for some time. A commercially available system consists of a normal aerosol can with a second container built into it. The can contains the base paint and the inner container contains the hardener. If the user wants to use the paint, he must open the inner container from the outside and mix the paint and hardener by shaking. The mixture is sprayed out using a commercially available spray head for paints. In another system, the base paint is in an aerosol can measuring 67 x 157 mm and the hardener in a second can measuring 35 x 5 mm. To activate the base paint, the hardener must be poured through the valve of the large can. After the mixture has been shaken thoroughly, it can be sprayed using a commercially available spray head. Both systems have the crucial disadvantage that after the paint has been activated, there is only a limited amount of time during which the paint can be used. Once the time has elapsed, the mixture in the can becomes hard. If a user does not need the entire can, he or she must dispose of the rest.

To solve the disadvantages, the inventor set himself the task of developing an aerosol can with a suitable spray head for two-component paint, which makes it possible to mix the components outside the can, i.e. in the spray head. EP 0 111 089 discloses an aerosol can (Fig. 1) which allows mixing outside. A second container (8) is built into a commercially available aerosol can (9). It is screwed onto the valve plate (7). The valve body (5) leads to the inner container, the valve body (6) into the aerosol can. Two-component products can be filled into the aerosol can, which is divided into two chambers. As soon as the spray head (1) is pressed down, the valve bodies (5 and 6) are opened and the two partial fillings flow through the separate channels (2 and 3) in the spray head (1). They are mixed and dispensed in a connected spray tube (4).

The can with spray head and tube described has been used to date for foams; the design is not suitable for spray, especially paint spray. Instead of the spray tube, a specially designed nozzle construction must be attached. Fig. 2 shows the schematic structure of the spray head. In the spray head (1), two separate channels (2 and 3) lead at the lower end to the two valve bodies (5 and 6 from Fig. 1). At the upper end, they open into a mixing chamber (4 in Fig. 2). A special nozzle construction (5) is connected to the mixing chamber (4). Fig. 3 shows the nozzle construction in an enlarged view. The mixing chamber (4 from Fig. 2) extends into the mixing chamber (1 in Fig. 3). It ends at the first atomizer nozzle (2). The paint-hardener mixture roughly premixed in the mixing chamber (1) passes through the nozzle (2), is roughly atomized there for the first time and then reaches the second mixing chamber (3). The mixture is atomized a second time at nozzle 4, which results in the spray mist becoming finer. In the third mixing chamber (5), the now fine mist is mixed once again, further refined and then leaves the spray head through the three holes (6) in the molded part (7). The three holes have a very small diameter. This makes the spray pattern very fine. If only one hole were provided in the molded part (7), the spray rate would be far too low and the user would need too long to do anything.

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With the construction shown it is possible to produce an extremely fine spray pattern and an acceptable spray rate.

The increased diameter of the molded part (7) ensures a firm hold in the spray head.

It is also possible to create the three mixing chambers with atomizing nozzles by putting two half shells together. Fig. 4 shows the schematic structure. The half shell (1) when put together produces a molded part with several mixing chambers and holes. Part (2) in Fig. 4 is the first half shell, part (3) is the second half shell.

Claims (6)

1. Spray head for a pressure vessel for gases, liquids, pasty products or the like, the interior of which is divided into at least two chambers sealed against one another and which has a valve plate common to the chambers, into which an outlet valve is inserted for each chamber which is connected to its interior and which can be actuated jointly by a spray head which can be displaced in the axial direction in the sense of opening all the valves, characterized in that the spray head has at least two spray holes for atomizing the filling goods. 2. Spray head according to claim 1, characterized in that at least two mixing chambers and at least two atomizing nozzles are installed in the spray head for mixing and atomizing the filling materials. 3. Spray head according to claim 1 and 2, characterized in that two molded parts with one atomizer hole and one molded part with at least two atomizer holes are built into the spray head. 4. Spray head according to claim 1, characterized in that a molded part consisting of two half-shells according to Fig. 4 is installed. 5. Spray head according to claim 1 to 5, characterized in that the atomizer nozzles have a conical shape. 6. Spray head according to claim 1 to 6, characterized in that the atomizer nozzles have a cylindrical shape.