DE3221521C2 - Variable pitch propeller with nozzle - Google Patents

Abstract

The ship's propeller (1) has blades (7) with outer edges which are delimited by circularly curved outer surfaces (12) which interact with a spherical zone (Z) of a spherical surface which is formed on the inner surface (8) of the nozzle (2) . The common center point of the spherical zone (Z) and the circularly curved outer surfaces (12) of the blades (7) lies at the intersection (O) of the axes of rotation (P) of the blades (7), which in turn lies on the propeller axis (A).

Description

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right surface inclined away in the direction of flow By this measure, the flow conditions in the nozzle can be improved even further, by further reducing an expansion of the flow in the area of the zone of the spherical surface.

The angle of inclination of the wing axes can be opposite the surface perpendicular to the propeller axis be chosen such that the downstream edge of the Spherical zone of the nozzle in the area of a perpendicular to the propeller axis leading through the intersection Area or downstream of this area is by this measure an evaluation of the flow avoided at all in the area of the spherical zone.

Optimal relationships between Propeller and nozzle are obtained if not only the outer surfaces of the blades but also the zone of the The spherical surface of the nozzle is machined.

The invention is explained with reference to exemplary embodiments shown schematically in the drawing shows

F i g. 1 shows a partial section with a partial view of a first embodiment of a controllable pitch propeller according to the invention with nozzle,

F i g. 2 shows a partial section along the line II-II in FIG. 1 and

F i g. 3 shows a section from FIG. 1 corresponding representation of a further embodiment the invention.

The F i g. 1 shows a controllable pitch propeller 1 which is provided with a so-called Kort nozzle 2. The controllable pitch propeller 1 contains a hub 3 which is attached to a flange 4 of a propeller shaft 5, which in turn is rotatably mounted in a bearing 6 arranged on the hull (not shown). In the hub 3, propeller blades 7 are mounted in a manner known per se. which can be pivoted about wing axes P. The propeller blades are adjusted by pivoting about the blade axes P with the aid of an adjustment mechanism known per se, not shown, preferably by hydraulic pressure medium which is supplied through the hollow propeller shaft 5. In this embodiment, the blade axes P are perpendicular to the propeller axis A and therefore run in a surface E perpendicular to the propeller axis A

The nozzle 2 has, as shown in FIG. 1 an inner surface 8, which has an annular zone Z of a spherical surface, the center point 0 of which lies on the propeller axis A , namely at the point at which the blade axes P of the propeller blades 7 also intersect at the same time. As shown in FIG. 1, the spherical zone Z is laterally bounded by two edge lines 10 and 11, which, however, do not form any sharp edges, but which are followed by rounded transition surfaces.

As shown in FIG. 2 can be seen, the spherical zone Z has a radius R 1, while the outer surface 12 of the propeller blade 7 has a radius R 2, which is a gap width D smaller than the radius R 1. The gap width D can, depending on the size of the propeller and the desired accuracy, be a few millimeters to a fraction of a millimeter.

As further from FIG. 1 can be seen, the intersection line 9 of the surface E described by the vane axes P with the spherical zone Z divides this into two sections B and C. The upstream section B in relation to the flow direction S is shorter than the downstream section C.

In the embodiment according to FIG. 3 are the

Rügelachsen P of the propeller blades from the perpendicular to the propeller axis A surface £ Ίη flow direction Sum an angle inclined λ The area described by the blade axes P in this case is a conical surface K. In the illustrated embodiment the inclination angle α of the vane axis P of the propeller blades 7 so selected that the upstream edge 11 of the spherical zone Zin of the nozzle 2 lies in the area of the surface E leading through the intersection 0 and perpendicular to the propeller axis A the tangent T to the spherical surface runs parallel to the propeller axis A. It goes without saying, however, that the angle α can be chosen to be even larger.

In all of the illustrated embodiments, the axial length and the position of the spherical zone Z on the nozzle 2 chosen such that at the respectively shown largest angle of attack / the propeller flights] the ends 20 of the Outer surfaces 12 of the wings 7 coincide with dt:, edges 10 and 11 of the zone Z.

At least in the area of the spherical zone Z, the inner surface 8 of the nozzle is machined in order to achieve the smallest possible gap D.

In the fig. 1 shows two possible measures for removing the propeller blades

So either the nozzle with a blanket! 21, which closes an opening 22 in the nozzle 2 by means of which, after removing the cover 21, one of the blades 7 is removed after the other can.

In the lower part of FIG. 1 shows a trough 23 which is formed by a welded-in terminating part 24 is locked. When replacing one or more propeller blades, the end part 24 is cut out, whereupon the individual propeller blades are brought into the appropriate position by rotating the hub 3 can be, in which they are lowered into the Muixie 23 and then laterally pulled out of the hub can be.

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Claims (6)

ι 1 2 according to DE-OS 21 03 568, compliance with a mini patent claims: paint gap between the outer edges of the wing and the inner surface of the nozzle only with a single 1. Variable pitch propeller (1) with nozzle (2) for ships, wing position possible, namely in the area of one of its flights! (7) can be swiveled about stirrup axes (P) 5 angle of incidence zero, where there is no driving force. At are that intersect at an intersection (O), the operating position with a large angle of attack, at which the propeller axis (A) lies, whereby the wing rather a good efficiency must be aimed for, gel (7) in each case on both sides on the other hand, wedge-shaped, widening gaps (P) extend from the wing axis, the outer surfaces (12) of the parts of a spherical surface between the ends of the wings and the inner surface of the wings (7), the central nozzle of which the efficiency of the unit propeller point is at the intersection (0) of the blade axes (P) , deteriorate the nozzle. the inner surface (8) of the nozzle (2) with a spherical zone In addition, there is the risk that in the wedge-shaped (Z) is provided whose center point is also in the gap between the end of a wing and the Intersection (0) of the vane axes (P) and the inner surface of which foreign bodies can penetrate the nozzle. Radius (R 1) around a given gap (D) greater than 15 £: e can damage the propeller blade, is as the radius (R 2) of the outer surfaces (12) from US Pat. No. 16 00654, an impeller is special Blade (7), characterized in that known for turbines that is arranged in a pipeline the spherical zone (Z) is from a line of intersection (9) with net, which at its end has a taper a FIa described by the vane axes (P) has a spherical surface. However, the impeller can before (E, Fig. 1, K, Fig. 3) upstream as well as upstream as a drive propeller in the water or in the air extends downwards, in such a way that when the greatest contingency is reached, they are used. angle iß) of the blades (7) the ends (20) of the outer surface The impeller has automatically pivoting blades, surface of the wings (7) with the edges (10, 11) of the kerren outer surfaces are parts of a spherical surface, the gel zone (Z) coincide. The center point is at the intersection of the block axes. the 2. Variable pitch propeller according to claim 1, characterized in that the inner surface of the pipe end is marked with a spherical zone that the spherical zone (Z) can be seen from the center of which is also at the intersection of the line of intersection (9) with that of the blade axes (P) The wing axis is located at a given described area whose radius is greater downstream by a larger gap than the radius of the outer surface of the outer section fQ than upstream (from wing. The spherical zone as well as the wing extend section B). M, however, only extends downstream from the 3. controllable pitch propeller according to claim 1 or 2, there axes described surface. characterized in that the through the wing the invention has the creation of a Verstellpropelsen (P) described Fiäne a to the propeller axis lers with nozzle to the goal, with which on the one hand an opti-Msenkrechte area (E) m {¥ \ z .. 1, 2). painter efficiency is achievable and on the other hand the 4. Variable pitch propeller according to one of claims 1 35 risk of damage to the propeller blades by between or 2, characterized in that the wing end see wing tip and nozzle penetrating foreign bodies, sen (P) from a to the propeller axis (A) perpendicular such. B. pieces of ice in ice propellers is reduced.
Surface (E) are inclined in the direction of flow (S) . The variable-pitch propeller according to the invention with a nozzle. (Fig. 3 / angle of inclination λ). through which this goal is achieved \ τ> τά, is thereby 5. Variable pitch propeller according to claim 4, characterized in that the spherical zone is characterized by a section that the angle of inclination (λ) of the wing line with one described by the wing axes (P) relative to the propeller axis (A) Surface upstream and downstream extends, the vertical surface (E) is chosen such that at the greatest angle of attack of the wings the ends of the upstream edge (11) of the spherical zone (Z) in the outer surfaces of the wings with the edges of the Ku nozzle (2) coincide in the area of a gel zone through the intersection (0) 45. leading surface perpendicular to the propeller axis (A) This measure ensures that with all before (E) or downstream of this area (E) Angular positions of the propeller blades the gap between lies. see the outer surfaces of the wings and the inner surface 6. Variable pitch propeller according to one of claims 1, the nozzle remains the same size and therefore in all Stellunbis 5, characterized in that the zone (Z) of the 50 gene can be minimal. This means that all spherical surfaces of the nozzle (2) can be machined and the propeller blades are optimally efficient can be obtained. Also, because of the minimal Size of the gap practically eliminates the risk. that foreign bodies can get between the outer surfaces of the flow gel and the inner surface of the nozzle. The invention relates to a controllable pitch propeller with Du- Preferably, the spherical zone of a se for ships, the wings of which swivel around wing axes - intersection line with a through the axes of rotation of the wings are bar that intersect at an intersection, the area described downstream by a larger lies on the propeller axis, with the blades each section extending as upstream. At a sol- If the embodiment extends on both sides from the wing axis, the flow is through the kcn. the outer surfaces of the wing parts of a Ku nozzle favored by the fact that an expansion of the gel surface, the center of which is at the intersection of the flow in the area of the zone of the spherical surface Flügclachsen is located, the inner surface of the nozzle is restricted with a. Spherical zone is provided, the center of which can also be in the area described by the wing axes The point of intersection of the blade axes is and the radius 65 of which is a surface perpendicular to the propeller axis, as is the case by a given gap is greater than the radius which is already known from US Pat. No. 1,600,654. It is External surfaces of the wings. however, it is also possible to arrange the propeller blades in this way. In the known controllable pitch propellers of this type, e.g. B. that their axes of rotation from a lower to the propeller axis