Fluid dispensing gun and method for dispensing 1K-polyurethane foam

Abstract

A fluid dispensing gun for 1K-polyurethane foam includes a dispensing tube with a dosing nozzle at its outlet, a spring-loaded needle co-axially moveable in the dispensing tube for opening and closing the dosing nozzle, a trigger actuating the needle to open the nozzle and to dispense the fluid, a regulator regulating the degree of opening of the nozzle outlet and a coupler coupling a pressurized can to the gun. It also concerns a method for dispensing 1K-polyurethane foam. The fluid dispensing gun includes a delivery device delivering a curing fluid essentially parallel to the nozzle outlet that includes a curing fluid reservoir, a curing fluid outlet situated near the nozzle and a curing fluid line connecting the curing fluid reservoir and the curing fluid outlet, the trigger activating the delivery device. The curing fluid delivered in the same direction as the 1K-polyurethane foam and separately therefrom makes the foam cure more rapidly.

Claims

1. A fluid dispensing gun for 1K-polyurethane foam comprising a dispensing tube (3) with a dosing nozzle (4) at its outlet, a spring-loaded needle which is co-axially moveable in the dispensing tube (3) for opening and closing the dosing nozzle (4), a trigger (6) for actuating said spring-loaded needle in order to open the dosing nozzle (4) and to dispense the fluid, regulating means (7) for regulating the degree of opening of the outlet of the dosing nozzle (4) and coupling means (2) for coupling a pressurized can to the fluid dispensing gun, wherein the fluid dispensing gun comprises means (8, 9, 10) for delivering a curing fluid separately from the 1K-polyurethane foam in a direction which is essentially parallel to that of the outlet of the dosing nozzle (4) of the dispensing tube, the means (8, 9, 10) for delivering a curing fluid comprising a curing fluid reservoir (8), a curing fluid outlet (10) situated in proximity of the dosing nozzle (4) of the dispensing tube and a curing fluid line (9) connecting the curing fluid reservoir (8) and the curing fluid outlet (10), the means (8, 9, 10) for delivering a curing fluid being activated via the trigger (6) of the fluid dispensing gun.

2. The fluid dispensing gun according to claim 1, wherein the curing fluid reservoir (8) is a pressurized reservoir (8) on the fluid dispensing gun provided with a valve for delivering the curing fluid from the curing fluid reservoir (8) to the curing fluid outlet (10).

3. The fluid dispensing gun according to claim 1, wherein the curing fluid reservoir (8) is a non-pressurized reservoir (8) on the fluid dispensing gun that comprises a pump for pumping the curing fluid from the curing fluid reservoir (8) via the curing fluid line (9) to the curing fluid outlet (10).

4. The fluid dispensing gun according to claim 1, wherein the curing fluid reservoir (8) is arranged on the lower side of the fluid dispensing gun.

5. The fluid dispensing gun according to claim 1, wherein the curing fluid reservoir (8) is arranged on the upper side of the fluid dispensing gun.

6. The fluid dispensing gun according to claim 1, wherein the curing fluid reservoir (8) is at least partly transparent.

7. The fluid dispensing gun according to claim 1, wherein the curing fluid outlet (10) is designed as a spray nozzle.

8. The fluid dispensing gun according to claim 1, wherein control means are provided for starting the curing fluid delivery when the trigger (6) of the dispensing gun is activated.

9. The fluid dispensing gun according to claim 1, wherein the fluid dispensing gun has an inner thread for fixing a ring onto which the curing fluid reservoir (8) is fixed by means of a second thread.

10. A method for dispensing 1K-polyurethane foam with the fluid dispensing gun according to claim 1, wherein curing fluid is delivered from a curing fluid reservoir (8) via a separate fluid line (9) to a curing fluid outlet (10) in an essentially parallel direction of the outlet of the dosing nozzle (4) of the dispensing tube of the fluid dispensing gun upon activation of the trigger (6) of the fluid dispensing gun.

11. The method according to claim 9, wherein the curing fluid is delivered in form of a spray.

12. The method according to claim 10, wherein the curing fluid delivery starts before the delivery of the 1K-polyurethane foam.

13. The method according to claim 10, wherein the curing fluid delivery starts at the same time as the delivery of the 1K-polyurethane foam.

14. The method according to claim 10, wherein the curing fluid delivery starts after the delivery of the 1K-polyurethane foam.

Description

(1) In the following, a preferred embodiment of the invention is described with reference to the figures wherein

(2) FIG. 1 shows a side view of a first fluid dispensing gun according to the invention,

(3) FIG. 2 shows a longitudinal cut through the fluid dispensing gun according to FIG. 1,

(4) FIG. 3 shows a side view of a second fluid dispensing gun according to the invention with the curing fluid reservoir in an unmounted state,

(5) FIG. 4 shows a longitudinal cut of the fluid dispensing gun according to FIG. 3 with the curing fluid reservoir in an unmounted state,

(6) FIG. 5 shows a side view of a second fluid dispensing gun according to the invention with the curing fluid reservoir in a mounted state.

(7) The fluid dispensing gun according to the invention comprises a housing 1 on the upper side of which coupling means 2 for coupling a pressurized can to the gun are arranged.

(8) The means 2 for coupling a pressurized can are connected via a fluid line to a dispensing tube 3 with a dosing nozzle 4 at its outlet. A spring-loaded needle is co-axially moveable in the dispensing tube 3 for opening and closing the dosing nozzle 4.

(9) There is a handle 5 for holding the gun during operation. The user can actuate said needle by pushing on a trigger 6 situated on the lower side of the housing 1 in front of the handle. By actuating the needle, he opens the dosing nozzle 4 in order to dispense the fluid.

(10) At the free end of the fluid dispensing gun opposed to the dosing nozzle 4, regulating means 7 for regulating the degree of opening of the outlet of the dosing nozzle are provided. By turning these regulating means, the degree of opening of the outlet is modified.

(11) The fluid dispensing gun according to the present invention comprises means 8, 9, 10 for delivering curing fluid to a curing fluid outlet 10 situated in proximity of the outlet of the dispensing tube 3. These means comprise a curing fluid reservoir 8, a curing fluid outlet 10 situated in proximity of the outlet of the dispensing tube 3 and a curing fluid line 9 connecting the curing fluid reservoir 8 and the curing fluid outlet 10. The curing fluid is transported and delivered separately from the 1-K polyurethane so that no mixing thereof occurs in the fluid dispensing gun.

(12) In the first embodiment shown in FIGS. 1 and 2, the curing fluid reservoir 8 is configured as a pressurized reservoir 8 situated on the lower side of the fluid dispensing gun in front of the trigger 6. This reservoir 8 may serve as a second handle of the fluid dispensing gun. The reservoir 8 is made of transparent material so that the curing fluid level can easily be controlled.

(13) The curing fluid outlet 10 is designed as a spray nozzle. Depending on the movement of the fluid dispensing gun during the 1K-polyurethane application, the curing fluid outlet nozzle 10 can be turned around the dispensing tube 3 of the fluid dispensing gun.

(14) Control means are provided for starting the curing fluid delivery when the trigger 6 of the dispensing gun is activated. These control means can be mechanical or electronic control means. When the trigger 6 is activated, the opening of the dosing nozzle 4 is preferably slightly delayed so that the surface is moistened with the curing fluid before the 1K-polyurethane foam comes out of the dosing nozzle. The curing fluid will be sprayed while dispensing the 1K-polyurethane foam. This solution allows moistening the area in which 1K-polyurethane foam is sprayed afterwards.

(15) However, it is also possible that the curing fluid delivery starts either at the same time as the delivery of the 1K-polyurethane foam or after the delivery of the 1K-polyurethane foam. The first solution allows moistening the 1K-polyurethane foam upon leaving the outlet of the fluid dispensing gun and the second one allows moistening the already dispensed 1K-polyurethane foam.

(16) The second embodiment of the invention shown in FIGS. 3, 4 and 5 differs from the first embodiment in that the curing fluid reservoir 8 is on the upper side of the fluid dispensing gun, just behind the means 2 for coupling a pressurized can so that the reservoir 8 and the pressurized can containing the 1-K polyurethane are one behind the other on the upper side of the fluid dispensing can.

(17) It can be seen from the FIGS. 3, 4 and 5 that the fluid dispensing gun has an inner thread for fixing a ring onto which the curing fluid reservoir 8 is fixed by means of a second thread.

(18) Furthermore, the curing fluid outlet 10 is shown on the upper side of the dosing nozzle 4 for the 1-K polyurethane. However, it is possible to unscrew the fixation of the curing fluid outlet 10 and to turn it by 180° around the dispensing tube 3 so that the curing fluid outlet 10 is on the lower side of the dosing nozzle 4 for the 1-K polyurethane foam. It also could be turned by another angle, e.g. by 90° in order to have the curing fluid outlet 10 at one side of the dispensing tube 3.

(19) Instead of dispensing the curing fluid parallel to the direction of the dosing nozzle 4, it is also possible to dispense it in another direction, if suitable for the application.