CZ306629B6 - A nozzle of a gun for application of polyurethane foam through a flexible attachment and a gun with such a nozzle - Google Patents

Abstract

The nozzle (11) of the gun (10) for application of polyurethane form through the flexible attachment (1) consists of a cylindrical end part and a connecting part with a thread for screwing on the outlet pipe of the gun. The closing valve wire passes through the nozzle. The nozzle (11) is provided with the thread (14) executed on the outer surface of the end functional part (17). The gun (10) is executed in such a way that its end is connected to the nozzle (11) with the thread (14) executed as a screw thread with a high pitch or as a metric thread.

Description

Gun nozzle for applying polyurethane foam via a flexible attachment and a gun with such a nozzle

Field of technology

The invention relates to the professional application of polyurethane foam from guns, on which cans with this foam are mounted.

Prior art

The use of polyurethane foam is very widespread in the construction industry, eg for the settling of windows, door frames, for permanent and temporary filling of cavities and in general for permanent or temporary fixation of various structures.

The foam can be applied with simple extensions directly from the can, but because the can has to be upside down, it is strenuous. That's why guns have spread among professionals years ago, which have a clamping ring head at the top to seat the can, and the operator can conveniently apply the foam by pressing the trigger. Inside the gun there is a solid wire which ends in a nozzle mounted at the end of the discharge pipe in its small discharge opening, when the nozzle is screwed to the end of the discharge pipe, and the wire closes the opening in the nozzle, resp. opens, so it serves as a valve for the entire gun. Such pistols with said nozzle are known, for example, from WO91 / 16139. In more modern embodiments, the nozzle is provided with a short cylindrical extension on the surface provided with a corrugation, on which a conventional plastic straight application tube can be slid, and thus the range of application of the foam can be further increased. To allow foam to be applied to the joints, and as far away from the gun body as possible, the length of the discharge pipe is usually about 20 cm. The discharge pipe usually has two diameters. Larger at the beginning and smaller at the end and there is a nozzle on it. All this to allow the greatest possible reach to the places where the foam is to be applied.

The inventor of the present invention published in CZ 28468 U1 a general idea of how to use its solution in the form of an elongated flexible extension for applying PU foam to hard-to-reach places, e.g. under the ceiling, which is impossible by conventional means, also for a pistol. There is a schematic outline of how to attach the nozzle tube to the gun, but without any specification of a reliable attachment to the end of the discharge tube. It is obvious that the attachment is far from the trigger in the design, it would have to be held with an uncomfortable distance from the can with the other hand, it would sway and it would be difficult to work with it.

The object of the invention is to present a nozzle which would allow the extension of the extended flexible attachment also on a pistol for professionals and at the same time to present a pistol which would allow comfortable working with the extended flexible attachment and which would allow easy and safe mounting or removing this attachment.

The essence of the invention

The above-mentioned drawbacks are eliminated by the nozzle of a gun for applying polyurethane foam via a flexible attachment according to the invention, the essence of which consists in that the nozzle is provided with a thread made on the outer surface of the end functional part of the nozzle.

In a preferred embodiment, the thread is designed as a screw thread with a high pitch, corresponding to the pitch of the thread inside the inlet part to the actuator for discharging the foam liquid directly from the can.

In another preferred embodiment, the thread is designed as a metric thread to cut it inside the inlet portion of the actuator to discharge the foam liquid directly from the can.

- 1 CZ 306629 B6

In another preferred embodiment, the functional part towards the outlet tube is terminated by a concave sealing shoulder.

Another object of the invention is a pistol for fixing a flexible attachment for applying PU foam to hard-to-reach places, the essence of which lies in the fact that it is provided with a nozzle according to one of the preceding features.

Explanation of drawings

The invention will be further illustrated by the drawings in which Fig. 1 shows a detail of a flexible attachment for applying PU foam to hard-to-reach places developed by the inventor, Fig. 2 is an overall view of a flexible attachment mounted directly on a standard can; according to the invention for fixing a flexible nozzle for applying PU foam to hard-to-reach places, Fig. 4 shows a detail of a nozzle of a gun for applying polyurethane foam according to the invention in a first embodiment, Fig. 5 shows a nozzle of a gun for applying polyurethane foam according to the invention in a second embodiment; 6 shows a nozzle of a gun for applying polyurethane foam according to the invention in a third embodiment of a gun according to the invention for fixing a flexible extension for applying PU foam to hard-to-reach places, and FIG. 7 shows the whole assembly of gun and flexible attachment.

Example of an embodiment of the invention

The inventor has improved the flexible attachment for applying PU foam to hard-to-reach places, shown in its end part in Fig. 1. The flexible extension 1 consists of an actuator 2 which has an outlet tube 3 at the outlet and has an opening into which it is a hook. 14 a wire 4 mounted otherwise loosely in the tube 5 is fixed. At the entrance to the actuator 2, the inlet cylindrical cavity 6 with the control arms 8 and the inlet cavity 6 are provided with an internal worm thread 7 with a large pitch.

This thread 7 corresponds to the thread on the discharge valve 16 on the plate 9. The can 9 can be seen in Fig. 2, together with the attachment 1, together with the attachment 1. It is thus clear that the extension 1 thus terminated by the manual control 2 is originally intended for foam application directly. from box 9 without using a pistol.

As a development task, it was therefore necessary to solve how to attach the attachment 1 to professional pistols as well. This is because a conventional pistol with a conventional end nozzle has not been usable, as mentioned above, because the described flexible attachment 1 cannot be mounted on it either with or without the standard actuator 2, i.e. directly a tube with a wire.

In the first phase, it was considered to provide the end of the metal discharge nozzle from the gun with a hole for the wire and by pulling the tube, which would still need to be fastened with a clamp. However, the nozzle wall is thin and the distance between the inner surface of the nozzle and the valve wire arranged inside is too small and the hook could not be sufficiently inserted. Without it, making holes in the steel nozzle would mean, in addition to the difficult assembly, that when working without a flexible attachment, foam would escape through the hole. It has also been considered to cover the opening with a cap or adhesive tape, but even these solutions do not suit ·

The solution is a modified professional pistol 10 provided with a nozzle 11 according to the invention. This gun 10 is shown in Fig. 3. The gun 10 has only a short outlet tube 12, usually of metal, and melts molded in the gun tip 15, the outlet tube 12 and the nozzle 11 being several times shorter than the discharge tube of conventional guns. In particular, the distance D from the center of the foam supply pipe 13 and the end of the entire outlet pipe 12 i with the nozzle is at most 12 cm, but preferably 7 cm. With a conventional pistol, this distance is normally 21 cm, and conventional plastic application tubes are fitted to the common end cap. It is therefore 3x shorter. A common guide is guided inside the nozzle 11, but in this case

-2GB 306629 B6 also an adequately shortened shut-off valve wire 2L The nozzle 11 can be manufactured by machining or as a casting.

Another decisive feature that makes the tool for working with the flexible attachment 1 out of the shortened gun 10 is the thread 14 on the outer surface of the end functional part 17 of the nozzle LL It is this thread 14, which is preferably made as a large screw thread with a large pitch corresponding to the pitch. of the internal thread 7 on the actuator 4, of the flexible extension 1, will allow that said flexible extension 1 can be securely mounted on the pistol 10 without any modifications.

Fig. 4 shows in detail a first embodiment of a nozzle 11 of a gun 10 for applying polyurethane foam according to the invention in a first basic preferred embodiment, i.e. as an end with an outlet tube 12 in one piece firmly cast into a plastic body, i.e. a gun end 15. the length L of the end portion is up to 10 mm, the length L of the nozzle according to the invention is in the range of 10 to 17 mm. The optimal upper limit appears to be 15 mm.

This nozzle 11 is also universal, because if a flexible attachment 1 is not needed for work, it can be removed and a conventional plastic straight tube can be easily inserted on the nozzle 11, and the pistol can be operated like a conventional pistol with a long discharge tube. A pistol with such a nozzle is therefore universal.

The internal thread 7 on the inlet cavity 6 is used in standard actuators 2 because the actuator 2 is screwed through it onto a standard dose valve lug.

Instead of a thread 14 made on the nozzle 11 as a screw thread, it is also possible to use, for example, a metric thread, which would be cut because it is metal, into the inlet cavity 6 of the plastic actuator 4, but this would require some force, deployment may not be coaxial and the actuator 2 it could easily deform at the inlet and even such a thread would wear out on the nozzle 11.

In order for the connection of the inlet cavity 6 at the inlet end of the actuator 2 of the flexible extension 1 and the nozzle 11 to be snug and tight, it is advantageous if the end part of the nozzle 11 towards the outlet tube 12 terminates with a concave sealing rounding 18. This corresponds to the convex arcuate end 19 of the input to the controller 2.

Fig. 5 shows a variant in which the nozzle 11 is provided with an external thread and this is screwed into the internal thread in the outlet tube 12.

Fig. 6 shows another variant in which the nozzle 11 is provided with a nut 20 with an internal thread and is screwed into the external thread in the outlet tube 12.

The flexible attachment of Fig. 1 is screwed onto the nozzle 11 made in this way by its actuator and the assembly shown in Fig. 7 is created. This creates perfect conditions for the user, as the fluid pressure is not lost by flowing in a standard gun with a long discharge tube. fix the extension with your hands with your hands, where the palm comfortably surrounds the can and rests on it. The user can continue to use the flexible attachment 1 even in a situation where he would no longer need it theoretically, but if he decides to save it, the attachment 1 unscrews and attaches a normal straight tube to the end and works in normal mode as with standard pistols. The tip is therefore universal, without any modifications.

The arms of the actuator function as a lever for screwing and unscrewing, and thanks to the angle between the inlet pipe and the outlet pipe of the actuator 2, the first bend of the adapter has an optimal geometry. It is, of course, possible to use an element other than the arm control at the end of the extension. But this allows the versatility of a flexible attachment for manual discharge of foam from the can and machine through the gun.

The above design is aimed at connecting the gun and the attachment with a thread. However, it is evident that if we do not rely on the universality of the use of the attachment, the connection can be made differently, eg the nozzle can have a tongue and a groove in the plug-in element, or there can be a flexible sleeve or other resilient element on the nozzle and a ring on the plug-in element. and pushing will result in a firm but detachable connection. A bayonet connection can also be used. The said actuator can also be provided with a fixing element so that the attachment does not come out spontaneously, for example when the pistol is put down. After use, a suitable pin can be inserted into the free end of the flexible attachment as a blanking plug to prevent the foam from hardening inside the attachment. The attachment control can also be arm-free. The whole assembly - the actuator 2, the end of the tube 3 and the end of the wire 4 can be encapsulated in one compact hollow plug-in element.

Industrial applicability

The nozzle according to the invention makes it possible to mount a flexible moldable attachment on a professional pistol and thus apply PU foam completely safely and cleanly, ie without spraying around and on the user's clothes, which is common when using various amateur disposable solutions, such as attaching rubber hoses to the end of a long attachments for common pistols. In this way, it is possible to apply the foam to inaccessible places, where it is not possible to get with conventional pistols with common nozzles.

Claims (5)

PATENT CLAIMS A gun nozzle for applying polyurethane foam via a flexible extension consisting of an end cylindrical part and a threaded connecting part for screwing on the gun outlet tube and a closing valve wire is guided inside the nozzle, a plastic tube being fitted to the nozzle as an extension, characterized that the outer surface of the end functional part (17) of the nozzle (11) is provided with a thread (14). Nozzle according to claim 1, characterized in that the thread (14) is designed as a screw thread with a high pitch, corresponding to the pitch of the thread inside the inlet part to the actuator for discharging the foam liquid directly from the can. Nozzle according to claim 1, characterized in that the thread (14) is designed as a metric thread for cutting it into the inner inlet part of the actuator for discharging the foam liquid directly from the can. Nozzle according to Claims 1 to 3, characterized in that the functional part (17) is terminated towards the outlet tube (12) by a concave sealing shoulder (18). A gun for fixing a flexible attachment for applying PU foam to hard-to-reach places, comprising an outlet tube terminated by a nozzle, and a shut-off valve wire is guided inside the gun, characterized in that it is provided with a nozzle (11) according to one of the preceding claims.