WO2002075228A1

WO2002075228A1 - Snow cannon provided with a spraying device for liquids

Info

Publication number: WO2002075228A1
Application number: PCT/AT2002/000078
Authority: WO
Inventors: Harald Koller
Original assignee: Harald Koller
Priority date: 2001-03-15
Filing date: 2002-03-11
Publication date: 2002-09-26

Abstract

The invention relates to a snow cannon provided with a spraying device. Said spraying device (1) comprises a hollow shaft (3), which is rotatably connected to a motor (2) and which is preferably subjected to the action of pressurized water. A number of outlet openings (7), e.g. holes or slots, are provided in the wall (12) of the hollow shaft (3) for the water guided inside said hollow shaft (3).

Description

A SPRAYING DEVICE FOR LIQUID-PROVIDED SNOW CANNON

The invention relates to a snow cannon with an atomizing device.

The snow guns previously used for snow-making on slopes generally work with a pressure nozzle system, whereby a distinction is made between high pressure and low pressure. In high-pressure systems, air and water are mixed at high pressure, at least 10 bar, and atomized via a coarse nozzle. The system has essentially proven to be technically unproblematic but energy-intensive. In low-pressure systems, water is sprayed through fine nozzles and blown into the air with an air jet generated by a fan. Although the system requires considerably less energy, it is controlled in a complicated manner, since the water flow must be adapted to the temperatures of air and water in the case of snowmaking. Such a scheme is complex and expensive.

Conventional snow cannons are known, for example, from EP 0 206705 A1, EP 27 79 33 A and AT 305 323 B. With these, water is sprayed from fixed nozzles into an air stream.

In order to bring about a nuclearization of the water crystals which have cooled below the freezing point, additional nuclearization nuclei are usually sprayed in, which cause the water to freeze and the snow crystals to form, as described, for example, in AT 305323 B. Such nucleation nuclei can be, for example, small frozen ice crystals (homogeneous nucleation). These can be generated by allowing a pressurized water-air mixture to flow out of a nozzle, the expansion resulting in a strong cooling (for example to temperatures below -40 ° C.) and the ice nuclei forming spontaneously. Other germs can also be introduced into the supercooled water droplet stream. Also the water supplied to the snow cannon chemical additives are added, whereby a separate nuclear gate device can be omitted.

A spraying device for glazes and the like is known from DE 9013829 U1. In this device, two opposing disks are arranged on a hollow shaft through which the glaze is guided. Furthermore, inclined rod-shaped elements are arranged between the two disks, so that the liquid, after being thrown out as a result of the centrifugal force through the openings of the rotating hollow shaft, is atomized when passing through the region in which the inclined rod elements are arranged. A cleaning device is known from DE 4000049 A1, in which the cleaning water is guided in a rotating hollow shaft that is pressurized with water, the wall of this hollow shaft being equipped with nozzles through which the water is sprayed. A disadvantage of this known prior art has been found in most cases that the liquid is not atomized finely enough and constant spray patterns can only be achieved with a complicated control.

From DE 43 08 842 A1, an atomizing device for liquids is also known, in which the liquid to be atomized is introduced into a rotating hollow shaft and is conveyed to the outlet openings via distribution elements. The use of such an atomizing device in a snow cannon would not be possible since, due to the ambient temperature prevailing in winter, the liquid would freeze when it was distributed or sprayed inside the hollow shaft onto the inner cylinder wall and onto the bores. The entire atomizing device would therefore be frozen over within a very short time.

The object of the invention is to provide a functionally reliable and economical snow cannon and according to the invention this is achieved by a snow cannon with the features of claim 1.

The snow cannon according to the invention, which can additionally have, for example, at least one rotatably mounted fan blade, is much safer and more economical to use, since instead of the previously usual 40 bar, only 2 to 3 bar are required. Even the freezing of individual parts that occurs time and again in the complex low-pressure snow machines can can be avoided with the snow cannon according to the invention, since the rotating disks are automatically thrown dry when the machine switches off. The water in the hollow shaft can be emptied automatically, for example, using a simple drain valve. In this way, it is possible with the snow cannon according to the invention to dispense with heating the technical facilities, which results in energy savings of 25% in comparison with low-pressure snow guns.

In an advantageous embodiment of the invention, it can be provided that in the area of the outlet openings radially outside, several disk-shaped distributor elements, which extend over the entire circumference and have at least one liquid guide channel, are arranged on the hollow shaft normal to the axis of rotation. As a result, the water in the channels is driven by the centrifugal force and atomized to the outside. If air pressure is fed into the hollow shaft in addition to the water, this effect increases, with the regulation of the spray pattern and the fineness of the atomization simply via the throughput of the water in the hollow shaft, which is between 0 1 / second and a multiple of the throughput Low pressure nozzle can vary, and the speed of rotation of the hollow shaft can be regulated.

According to a further advantageous embodiment of the invention, it can be provided that the disk-shaped distributor elements have a plurality of guide channels for the liquid to be atomized on their top and / or underside, preferably semicircular in cross section, wherein it has turned out to be particularly favorable according to a preferred embodiment when the disk-shaped distributor elements arranged on the circumference are pressed against one another in the direction of the axis of rotation of the hollow shaft and the guide channels of the top and bottom of two adjacent distributor elements correspond to form closed channels. For example, the filter disks that are well known on the market can be used as distributor elements. In addition to their simple handling, they also represent an inexpensive solution. If there were usually problems with clogged and calcified nozzles in the previously known solutions, which had to be cleaned in a complex and time-consuming manner, in contrast to this, the distributor elements in the atomizing device according to the invention can be replaced and cleaned simply and quickly. A particularly finely distributed spray pattern can be achieved if, as in a further embodiment of the Invention is provided that the guide channels of at least one distributor element, preferably curved in the direction of rotation of the rotating hollow shaft.

In order to be able to carry out specific snowmaking, it can further be provided that at least one fan blade and part of the hollow shaft, in particular the outlet openings, are arranged in a housing. This simple construction saves weight, which of course has advantages for transport in difficult terrain, especially since the snow cannon according to the invention can be produced in any size. The size of a fan gun is just as conceivable as a small device on a lance. Further advantages and details of the invention are explained in more detail in the following description of the figures with reference to the drawings. Show

F Fiigg .. 1 1 a sketchy representation of the atomizing device,

2a, 2b top view and view of a disc-shaped distributor element,

3a, 3b an enlarged section of two distributor elements pressed together,

Fig. 4 is a schematic representation of a hollow shaft and Fig. 5 5 and 66 embodiments of a snow cannon with the atomizing device according to the invention.

The atomization device for liquids 1 shown in FIG. 1 has a motor 2 and a hollow shaft 3 connected to it in a rotatable manner. The liquid to be atomized is fed via a feed line 8 to the drilled motor shaft 11 and subsequently to the rotating hollow shaft 3. Due to the rotation, the liquid is fed through the outlet openings 7 (not shown) in the wall 12 of the hollow shaft 3 to the channels 6 of the disk-shaped filter elements 4. Driven by the centrifugal force, the liquid penetrates through the channels 6 in the distributor elements 4 from the inside of the shaft to the outside, where it atomizes as it exits the channel 6.

In the disk-shaped distributor element 4 shown in FIGS. 2a and 2b, the guide channels 6 are curved. Such a shaping of the guide channels 6 has proven to be particularly favorable for fine atomization of the liquid, but care must be taken to ensure that the distributor elements 4 are arranged on the hollow shaft 3 such that the guide channels 6 are bent in the direction of rotation of the hollow shaft 3.

If several such distributor elements 4 are fanned out on the hollow shaft 3 and pressed together, the cutouts shown in FIGS. 3a and 3b result. In the section shown in FIG. 3 a, the disk-shaped distributor elements 4 have a plurality of guide channels 6 a, 6 b with a triangular cross section on their top and bottom sides. If the disk-shaped distributor elements 4 are now pressed together, the guide channels 6 b arranged on the underside of the distributor elements 4 correspond to the guide channels 6 a arranged on the top of the next distributor element 4, forming a closed channel 6. It goes without saying that the cross-section of the guide channels 6a, 6b does not play an important role, rather the fact that the guide channels 6a, 6b of two adjacent distributor elements 4 correspond to form closed channels 6 is decisive. The use of well-known filter disks, which are made of plastic, for example, represents a particularly cost-effective solution, since these filter disks are quick to clean and easy to replace. It also makes it possible to avoid the problems associated with the conventional pressure nozzle system with clogged and calcified nozzles and at the same time to dispense with water filters, water boxes, nozzles, nozzle rings and any heating required for the nozzles.

The hollow shaft 3 shown in FIG. 4 rotates about its axis of rotation 5. In the wall 12 of the hollow shaft 3 there are several outlet openings 7 for the liquid guided in the hollow shaft 3. As a result of the rotation and the centrifugal force generated thereby, the liquid is thrown outwards through the outlet openings 7 in the wall 12 of the hollow shaft 3. Due to the fact that the outlet openings 7 do not taper as usual, there can be no blockages, so that this system of rotating hollow shaft with disk-shaped distributor elements arranged thereon is far less susceptible to errors than other atomizing devices known from the prior art.

5 schematically shows a snow cannon 13 according to the invention, in which the described atomizing device is used. Water is fed into the motor shaft 11 of the motor 2 via the feed line 8 introduced and subsequently fed to the hollow shaft 3, which is rotatably connected to the motor 2. At the opposite end of the hollow shaft 3, a plurality of distributor elements 4 are arranged in the region of the outlet openings 7 (not shown) of the hollow shaft 3. In addition, a plurality of fan blades 9, 9 ′ are arranged on the hollow shaft 3 between the distributor elements 4 and the motor 2. If the hollow shaft 3 is now rotated by the motor 2 about the axis of rotation 5, the water penetrates the guide channels 6 in the distributor elements 4 to the outside, where it atomizes. A finer atomization can be achieved if compressed air is fed into the hollow shaft 3 via the feed line 8 in addition to the water. The fine water droplets are then transported further by an air stream which is generated by the fan blades 9, 9 ′ attached to the hollow shaft 3. In order to enable targeted snow-making, part of the hollow shaft 3, the fan blades 9, 9 'and the distributor elements are arranged in a housing 10.

FIG. 6 shows a snow cannon 13 in which the entire snow cannon is surrounded by a housing 10. In this embodiment, the fan blades 9, 9 'are arranged on the side of the motor 2 opposite the hollow shaft 3. The liquid is introduced into the hollow shaft 3 via the guide channel 8 via a hub 14. With regard to the mode of operation, reference is made to FIG. 5.

In order to achieve the nuclearization of the fine water droplets entrained by the air flow from the fan blades 9, 9 ′, the water supplied via the feed line 8 can be pretreated by adding chemicals conventionally used for this purpose. Furthermore, germs can be introduced into the air flow, for example frozen ice crystals. Nozzles 15 for introducing such germs are shown schematically in FIG. 5. For example, a plurality of nozzles 15 arranged in the region of the front outlet opening of the housing 10 and spaced apart from one another in the circumferential direction can be provided. These can be pressurized with a pressurized water-air mixture, so that ice crystals are formed due to the cooling occurring during the expansion of the air. The nozzles 15 could, for example, also be arranged on the hollow shaft 3, in front of or behind the distributor elements 4, with a plurality of nozzles 15 spaced apart from one another in the circumferential direction again being expediently provided. In order to form nucleation nuclei in the form of ice crystals, an additional compressed air line running through the hollow shaft 3 could be provided The compressed air-water mixture that emerges at the nozzles could be generated therein.

It goes without saying that the invention is not restricted to the exemplary embodiments shown. For example, it would also be possible to design the hollow shaft in the form of a hollow cylinder with a thick wall, so that the outlet openings could take over the function of the guide channels. However, the use of spiral leaf springs arranged on the circumferential side of the hollow shaft instead of the 6 distributor elements is also conceivable and possible. The atomization device used has a number of advantages over the conventional methods. In addition to the only low pressure that is required, the atomization device has, for example, a control range that extends up to many times that of conventional pressure-nozzle systems and begins at zero.

Claims

claims:

1. Snow cannon with an atomizing device, characterized in that the atomizing device (1) with a motor (2) rotatably connected, preferably pressurized water hollow shaft (3) and in the wall (12) of the hollow shaft (3) a plurality of outlet openings (7) , for example holes or slots, for the water guided in the hollow shaft (3).

2. Snow cannon according to claim 1, characterized in that in the region of the outlet openings (7) radially outside, several over the entire circumference, preferably disk-shaped distributor elements (4) with at least one liquid guide channel (6) normal to the axis of rotation (5) on the hollow shaft (3) are arranged.

Snow cannon according to Claim 1 or 2, characterized in that the disk-shaped distributor elements (4) have on their top and / or bottom side a plurality of guide channels (6a, 6b), preferably semicircular in cross section, for the water to be atomized.

4. Snow cannon according to claim 3, characterized in that the circumferentially arranged, disc-shaped distributor elements (4 ') in the direction of the axis of rotation (5) of the hollow shaft (3) are pressed together and the guide channels (6a, 6b) of the top and bottom of two Adjacent distributor elements (4) correspond to form closed channels (6).

5. Snow cannon according to one of claims 2 to 4, characterized in that the guide channels (6) of at least one distributor element (4), preferably run curved in the direction of rotation of the rotating hollow shaft (3).

6. Snow cannon according to one of claims 1 to 5, characterized in that the snow cannon (13) at least one rotatably mounted

Has fan blades (9, 9 ").

7. Snow cannon according to claim 6, characterized in that the fan blade (9, 9 ') on the hollow shaft (3) between the motor (2) and the outlet openings (7) is arranged.

8. Snow cannon according to claim 6 or 7, characterized in that at least one fan blade (9, 9 ') and part of the hollow shaft (3), in particular the outlet openings (7), are arranged in a housing (10).

9. Snow cannon according to one of claims 1 to 8, characterized in that nozzles (15) are provided for introducing the nuclearization of the atomized water droplets causing germs.