FI91513C - Nozzle propeller assembly - Google Patents

Description

91513

The invention relates to an extruder device, which propeller device comprises an annular propeller nozzle inside which a propeller driven by a propeller shaft is arranged.

As is previously known, the thrust of the propeller, in particular at low speeds, can be improved by means of an annular propeller nozzle around the propeller. In this case, the diameter of the propeller to be used can be slightly reduced in order to achieve sufficient thrust. However, under ice conditions, the extruder device causes a very significant problem, i.e. that the propeller device may become clogged when the bellows wedge between the propeller body and the nozzle or, on the other hand, when driving in the ice line when the front of the nozzle is filled. In both cases, the water supply to the propeller is blocked either partially or completely, resulting in a substantial reduction in the propulsion of the propeller. This problem is particularly pronounced with small kick-20 devices. In many cases, the propeller nozzle is not desired for the reasons mentioned above. For example, it has not been possible to use a propeller nozzle in harbor breakers, because in narrow harbor basins the ice is constricted and often accumulates even so that the pool has cramped ice to the bottom.

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Attempts have been made in the past to prevent nozzle clogging in a number of ways, but with considerable success. Attempts have been made to remove blockages in propeller nozzles that can be used without accessories by changing the direction of rotation of the propeller. However, this solution works poorly, especially in cases where there is a lot of cramped ice. At that time, Ålus is only able to travel very short distances at a time.

In addition, attempts have been made to treat the blockage by arranging various accessories in connection with the propeller nozzle device. Such solutions have previously been presented e.g. Finnish patent applications Nos. 861370 and 861371. These publications have attempted to treat blockages by attaching spikes or the like to the nozzle for the purpose of crushing the boulders or by arranging a ring in front of the propeller nozzle. block the propeller nozzle. However, these solutions have not eliminated the problem, but the boulders have still blocked the propeller nozzle because the boulders have adhered to said spikes or ring part.

Attempts have also been made in the past to prevent clogging of the nozzle by arranging a "jacket" in front of the nozzle, which prevents the ice blocks 10 from entering the nozzle. However, the main disadvantages of this solution are the high resistance caused by it and the poor durability. In addition, at low speeds, the "jacket" itself becomes clogged regardless of whether said jacket is streamlined or not. The cage may be filled with crushed ice, as suitably small pieces may pass through the cracks in the si-15 cage, but do not hit the correct position to come out of the same size crevice. Such cages may be fixedly mounted on the hull of the vessel, or, for example, in connection with a rotating propeller device, they may have been mounted on the propeller device itself to rotate with it. However, they have not been able to solve the problem of clogging 20, as stated above.

It is an object of the present invention to provide a nozzle propeller device which avoids the disadvantages associated with the prior art and prevents wedges from wedging between the body and the nozzle of the propeller device 25. In order to achieve this, the invention is essentially characterized in that inside the propeller nozzle, in front of a propeller arranged in a rotor, on the suction side of the propeller, on the same rotating shaft as the propeller, calculated, the corresponding radial dimension of the propeller is substantially smaller than Pi ·

The most significant advantage of the invention over the prior art solutions 35 is that when the prior art solutions have been "passive" with the sole aim of preventing the bricks 91513 3 from blocking the propeller device, the device according to the invention is arranged to operate "actively" in such a way that the device is provided with an arrangement which tends to crush large-sized boulders stuck in the propeller nozzle so that they can pass through the nozzle, whereby the nozzle itself is not blocked. At the same time, the crusher acts as a feed screw that compresses the ice cubes into the nozzle. Other advantages and features of the invention will become apparent from the following detailed description of the invention.

In the following, the invention will be described in detail with reference to the figures of the accompanying drawing.

Figure 1 is a schematic side view of an extruder propeller device according to the invention as a reversible propeller device implementation.

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Figure 2 corresponds to Figure 1 seen from the direction D.

Fig. 3 is a schematic sectional view of the propeller device of Figs. 1 and 2, showing an embodiment of the drive arrangement of the propeller device 20.

Figure 4 schematically shows an extruder device according to the invention implemented for conventional, non-rotating propeller operation.

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In Figures 1-3 of the drawing, the nozzle propeller device according to the invention is generally indicated by reference numeral 10. The nozzle propeller device 10 according to Figures 1-3 is e.g. a portable propeller device of the type previously disclosed in Finnish patent applications Nos. 30 830373 and 853173. a body 11 on which the propeller nozzle 12 is fixed by means of a support structure 13. A propeller 14 is rotatably arranged inside the propeller nozzle 12. Power is applied to the propeller device 10 by a vertical shaft 18 which drives a propeller shaft 22 via an angle gear 20 to which the propeller hub 15 is attached 35 and which propeller shaft 22 is rotatably mounted.

91513 4

In conventional propeller devices, the front part of the bevel gear body 21 is formed as a streamlined front view, but in the solution according to the invention the front cover is replaced by a rotating front piece 16 with paddles 17 attached to it. The front piece 16 is arranged on a rotor 5 with a rotor 14. The front piece 16 may be mounted on the propeller device body 11 for free rotation, but in the most preferred embodiment of the invention, the front piece 16 is arranged to be used. The purpose of the front piece 16 and the blades 17 attached thereto is to cause movement in the cooling charge in front of the propeller nozzle 12 10 and to crush the leg blocks in front of the propeller nozzle 12 so that they can pass through the propeller nozzle 12 or be guided outside the propeller nozzle. The blades 17 can be e.g. straight or spike-shaped, in which case they only act as a crusher, but on the other hand they can be shaped e.g.

15 as shown in the figures, so that in a way they act as a second propeller and as a control device for the crushed ice. The pallets 17 are drawn in a rather small size in the figures of the drawing, but their size can also be considerably larger than that shown in the figures, whereby

S

their working and crushing effect is improved.

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The propeller nozzle 12 is conventionally shaped so as to taper from its leading edge 12a until, after the narrowest point of the propeller nozzle 12, denoted A in the figures, continues substantially cylindrically, the propeller nozzle 16 means it is positioned with respect to the propeller nozzle 12 such that it is located at the narrowest point A of the propeller nozzle 12, at the beginning of or in front of the cylindrical portion. This ensures that the ice blocks are crushed so small that they can pass through the narrowest point A of the kick-30 spout.

It has already been stated above that the front body 16 acting as a crusher can be arranged in the propeller device 10 to be freely rotatable, but most preferably. min it is arranged to be used. Figure 3 shows an alternative implementation for the use of a front body 16 acting as a crusher. As already stated above, in the embodiment according to Fig. 3, the force 5 91513 is applied to the propeller shaft 22 on the vertical shaft 18 via a bevel gear 20. The bevel gear 20 consists of a first bevel gear 19 on the vertical shaft 18 and a second bevel gear 23 on the propeller shaft 22. In the embodiment of Figure 3, the kick shaft 5 is In the solution according to Fig. 3, the front body 16 acting as a crusher thus rotates in the same direction as the propeller 14 and at the same rotational speed.

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The user solution according to Figure 3 can be considered as the best implementation alternative of the invention, because it has the simplest structure and was thus the most reliable. However, the use of the front part 16, which acts as a crusher, can be mechanically arranged pre-arranged. so that the front piece 16 is arranged to rotate in the opposite direction to the propeller 14. The use of the front piece can then be implemented in a manner known per se, for example in accordance with Finnish patent application No. 861798. However, the structure of the propeller device then becomes more complicated than the solution shown in Fig. 3. However, the rotation of the front piece 16 can also be arranged, for example, electrically, hydraulically or in some other non-mechanical manner. However, such uses further increase the complexity of the design of the propeller device 10 and are

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thus, they were more expensive than mechanical use.

Figures 1-3 show the use of a front crusher 16 in connection with a rotatable propeller device 10 with a bevel gear 20. However, the invention can also be applied to conventional extruder devices and this has been schematically illustrated in Figure 4. In Figure 4, the hull of the vessel is indicated by reference numeral 5. The force is applied to the propeller 34 32, which is suitably attached to the hull 5 of the vessel. The attachment member is not shown in Fig. 4. In the embodiment of Figure 4, the propeller shaft 42 is extended 35 from the hull 5 of the vessel so far that a front piece 36 provided with blades 37 can be fitted between the propeller and the hull 5 and is suitably attached to the propeller shaft 42 in which the propeller hub 35 is also closed. In the embodiment of Figure 4, the front body 36 acting as a crusher thus rotates together with the propeller 34. With respect to the placement of the front piece 36, the following principle is followed, as already described above, i.e. the front piece is placed at or in front of the narrowest point A of the propeller nozzle 32.

In Figure 4, the nozzle propeller device is generally indicated by reference numeral 30, and the leading edge of the propeller nozzle 32 is indicated by reference numeral 32a and the edge of the drill-10 by reference numeral 32b. Although the nozzle propeller device 30 according to the invention can also be implemented in the conventional solution according to Fig. 4, problems can arise in this connection, e.g. with regard to the bearing of the propeller shaft 42, because the propeller shaft 42 is extended longer than in conventional solutions. Thus, the solution according to the invention may be considered the most advantageous in the embodiment of Figures 1-3. In Figures 1-3, the application of the invention is also more advantageous due to the fact that the front piece 16 and the blades 17 therein can be shaped more freely than in the solution of Figure 4.

The invention has been described above by way of example with reference to the figures of the accompanying drawing. However, it is not intended to limit the invention to the examples shown in the figures, but many modifications are possible within the scope of the inventive idea defined in the appended claims.

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Claims (10)

A nozzle propeller assembly, which includes a propeller assembly (10, 30), an annular propeller nozzle (12, 32) within which a propeller (14, 34) is driven by a propeller shaft (22, 42), characterized in that, in front of the propeller (14,34), in the suction side of the propeller, on the same axis of rotation (SS) as the propeller (14,34) arranged to rotate within the propeller nozzle, a rotating head (16,36) provided with blades (17, 37) or the corresponding projections and which act as ice crusher, in which the largest radial dimension of said blade (17,37) or corresponding projections, calculated from the axis of rotation (SS), is substantially smaller than the corresponding dimensions of the propeller (14,34 ). Device according to claim 1, characterized in that the front piece (16,36) which acts as an ice crusher and is provided with blades (17.37) or corresponding projections is provided with operation. 3. Device according to claim 1, characterized in that the front piece (16,36) which acts as an ice crusher and is provided with blades (17.37) or the corresponding projections is freely rotating. 4. Device according to claim 1 or 2, characterized in that the front piece (16,36) which acts as an ice crusher is arranged to rotate in the same direction of rotation as the propeller (14,34). 5. Device according to claim 4, characterized in that:. the front piece (16,36) is provided at the shaft (22,42) of the propeller to rotate therewith. 30 6. Device according to claim 1 or 2, wherein the drive power is hoisted to the propeller shaft (22) by forming a vertical shaft (18) and an angular shaft (20), characterized in that the front piece (16) acts as an ice crusher and is provided with blades. (17) is arranged to rotate in the opposite direction of rotation relative to the propeller (14). 91513 7. Device according to claim 1, 2 or 6, characterized in that the front piece (16) which functions as an ice crusher is provided with electric drive. 8. Device according to claim 1, 2 or 6, characterized in that the front piece (16) which acts as an ice crusher is provided with hydraulic operation. Device according to any one of the preceding claims, characterized in that the front piece (16,36) which acts as an ice crusher has been placed in the axial direction on the narrowest steel (A) of the propeller nozzle (12,32) or on it. front side of this. 10. Device according to any one of the preceding claims, characterized in that the blades (17,37) of the front piece (16,36) are shaped so that they are rising in such a way that their direction deviates from the direction of the axis of rotation. (SS). 9