DE9418745U1 - Spherical bearing for a rudder post - Google Patents

Description

BARKEMEYER Ship Technology GmbH
Birkenweg 11

21465 Reinbek

BKMlO7

Spherical bearing for a rudder shaft

Description

The invention relates to a spherical bearing for a rudder stock according to the preamble of claim 1.

From DE 34 34 387 Al a spherical bearing for a ship's rudder shaft is known, which has a bearing bush surrounding the rudder shaft, the outer surface of which has an outer convex spherical stop surface which is mounted in the concave inner surface of a two-part bearing shell.

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The upper and lower parts of the bearing shell can be adjusted in their position relative to one another and are connected to the ship's hull.

In order to install the spherical layer-shaped bearing bush in the two-part bearing shell of the known spherical bearing, a precise adjustment of the two bearing shell halves is required in order to achieve an even contact of the two concave spherical surfaces of the bearing shell halves on the convex surface of the bearing bush. When operating the known spherical bearing, there is a risk that a change in the position of the two bearing shell halves relative to each other will result in increased bearing play and unequal surface pressure of the concave and convex bearing surfaces of the bearing bush and the bearing shell half, resulting in premature wear of the known spherical bearing.

The object of the present invention is to create a spherical bearing for a rudder shaft of the type mentioned at the beginning, which is easy to install, requires no adjustment and ensures a permanent, consistent connection of the bearing surfaces of the bearing bush and bearing shell.

This object is achieved according to the invention by the characterizing feature of claim 1.

The solution according to the invention allows for very simple assembly when connecting the bearing bush to the bearing shell of the spherical bearing, and does not require any adjustments

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required and ensures a permanent, consistent contact between the convex bearing surface of the bearing bush and the concave bearing surface of the bearing shell.

To assemble the spherical bearing, it is only necessary to rotate the bearing bush by 90° relative to its position in the assembled spherical bearing, insert it in this position into the recess in the bearing shell and, in the final position, pivot it again by 90° around the transverse axis of the spherical bearing so that the convex spherical bearing surface of the bearing bush, which is located outside the recess in the bearing shell, comes into contact with the concave bearing surface of the bearing shell. In this position, the bearing bush is firmly mounted in the bearing shell with the convex bearing surface evenly resting on the concave bearing surface of the bearing shell.

The rudder shaft, which is guided in a bore in the bearing bush, can thus be pivoted around the center of the spherical bearing, so that during operation the rudder shaft cannot become tilted or jammed as a result of external forces or a misaligned arrangement of the rudder shaft.

The bearing bush preferably consists of a spherical layer that is symmetrical to the transverse axis of the spherical bearing. This design of the bearing bush, with a corresponding design of the counter bearing surface of the bearing shell, also includes geometric shapes of the bearing bush that form a spherical layer that is asymmetrical to the transverse axis of the spherical bearing.

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The depth of the recess is a function of the maximum diameter of the bearing bush, i.e. the depth of the recess must be dimensioned so that the maximum diameter of the bearing bush is at the deepest point of the recess. If the spherical layer shape of the bearing bush is asymmetrical to the transverse axis of the spherical bearing, the depth of the recess must be set equal to the vertical distance of the maximum diameter of the bearing bush from one of the two front or cover surfaces of the bearing bush.

In a design symmetrical to the transverse axis of the spherical bearing, the depth of the recess is greater than or equal to half the height of the bearing bush.

An advantageous embodiment of the solution according to the invention is characterized in that the recess in the bearing shell is provided in the cover surface of the bearing shell facing the rudder blade.

The arrangement of the recess on the top surface of the bearing shell facing the rudder blade enables easy assembly and disassembly of the bearing bush from the outside of a ship and ensures uniform pressure distribution on the top side of the spherical bearing with maximum bearing surface of the bearing bush and bearing shell.

In order to prevent the bearing bush from coming loose from the bearing shell after the bearing bush has been inserted into the bearing shell as a result of a rotation of the bearing bush about the transverse axis, in a further development of the solution according to the invention at least one securing element is provided on the recess

This securing element preferably consists of a securing ring, which is attached to the cover surface of the bearing shell or a bearing housing that has the recess.

In a further embodiment of the solution according to the invention, which can also be provided in addition to the securing element or securing ring, the cavity that remains after the bearing bush has been inserted into the bearing shell between the convex spherical bearing surface of the bearing bush and the recess wall of the bearing shell is at least partially filled by a supplementary element that can take on additional bearing shell functions, so that the convex spherical bearing surface of the bearing bush is surrounded by both the concave spherical bearing surface of the bearing shell and the likewise concave spherical bearing surface of the supplementary element.

In special cases, the supplementary element consists of a spherical wedge with a concave spherical bearing surface facing the convex spherical bearing surface of the bearing bush.

The spherical bearing is mounted in a bearing housing which is connected to the ship's hull to form a watertight passage of the rudder stock through the ship's hull.

The idea underlying the invention will be explained in more detail using an embodiment shown in the drawing. They show:

BKMlO7

Figure 1 - a longitudinal section through the spherical bearing according to the invention;

Figure 2 - a section through the spherical bearing along the line A-A according to Figure 1 and

Figure 3 - individual phases of assembly of the spherical bearing according to the invention.

The longitudinal section through the spherical bearing shown in Figure 1 shows, from the inside out, a rudder shaft 1 that can be rotated about an axis 8 and that is connected in a manner not shown in detail to a control device, for example a rowing machine, and to a rudder. The rudder shaft 1 is surrounded in the area of the spherical bearing by a rudder bushing 2, the inner surface 21 of which is adapted to the cross-sectional shape of the rudder shaft 1 and is connected to it by a press fit or the like.

The outer surface of the bearing bush 2 has a convex spherical bearing surface 22 as well as an upper and lower cover surface 24, 25, which, however, only consist of a narrow circular ring surface due to the bore for receiving the rudder shaft 1. The convex spherical bearing surface 22 forms the geometric shape of a spherical layer which runs symmetrically to the transverse axis 9 of the spherical bearing, so that the radius R of the spherical layer falls within the axis 8 of the rudder shaft 1 or the spherical bearing.

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The convex spherical bearing surface 22 of the bearing bush 2 is surrounded by a concave spherical bearing surface 31 of a bearing shell 3, the outer surface 32 of which is press-fitted into a bearing housing 4. The bearing housing 4 is connected to the ship's hull 5 in a manner known per se.

In the lower bearing half, a recess 33 is provided in the bearing shell 3 in the cover surface 35 of the bearing shell 3 facing the rudder (not shown in more detail), the depth T of which in this embodiment is approximately equal to half the height H of the bearing bush 2. As can be seen from the cross section through the spherical bearing shown in Figure 2 along the line A-A according to Figure 1, the cross section of the recess 3 shown in dash-dotted lines corresponds to the longitudinal section of the bearing bush 2 with side surfaces parallel to the cover surfaces 24, 25 of the bearing bush 2 and partially cylindrical end surfaces to the projected spherical bearing surface 22 of the bearing bush 2.

The distance B between the two parallel side surfaces corresponds to the height H of the bearing bush 2, while the two vertices of the partially cylindrical end face are spaced apart by a distance that is greater than or equal to the diameter of the bearing bush 2. Since the recess 3 3 of the bearing shell 3 is preferably produced by milling, slight deviations in the cross-sectional shape of the recess 3 3 from the longitudinal section of the bearing bush 2 occur in the end face areas.

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Since the depth T of the recess 33 is a function of the maximum diameter D of the bearing bush 2, the depth T of the recess 33 must generally be dimensioned such that the maximum diameter of the bearing bush 2 is at the deepest point of the recess 33. If the spherical layer shape of the bearing bush 2 is asymmetrical to the transverse axis of the spherical bearing, the depth of the recess is equal to the vertical distance of the maximum diameter of the bearing bush 2 from one of the two cover surfaces 24, 25 of the bearing bush 2. If the spherical layer shape is symmetrical to the transverse axis of the spherical bearing, the depth of the recess corresponds to half the height H of the bearing bush 2.

To secure the bearing bush 2 against accidentally falling out of the bearing shell 3, a locking ring 6 is arranged on the lower cover surface 35 of the bearing shell 3, which is connected to the bearing housing 4 via screw connections or the like. This locking ring 6 is fastened to the housing 4 after the bearing bush 2 has been installed, or removed before the bearing bush 2 is removed from the bearing shell 3.

Alternatively to this, or in addition to such a securing element or securing ring, the cavity that remains after the bearing bush 2 has been inserted into the bearing shell 3 between the convex spherical bearing surface of the bearing bush 2 and the recess wall of the bearing shell 3 can be at least partially filled by a supplementary element that can take on additional bearing shell functions, so that the convex spherical bearing surface of the bearing bush is supported both by the concave spherical bearing surface of the bearing shell and by the likewise concave

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spherical bearing surface of the supplementary element. This supplementary element can be connected either to the bearing shell or to the bearing housing. In the special case, the supplementary element consists of a spherical wedge with a concave spherical bearing surface facing the convex spherical bearing surface of the bearing bush.

The assembly process will be explained in more detail using the illustration in Figure 3.

Figure 3a shows a longitudinal section through the bearing shell 3 and the bearing housing 4 as well as a cross section through the bearing bush 2 before the final alignment of the bearing bush 2 to accommodate the bearing shaft according to Figure 1.

Figure 3c shows a longitudinal section through the bearing bush 2 corresponding to the longitudinal section according to Figure 1 before the assembly of the bearing bush 2 in the bearing shell 3. In order to assemble the bearing bush 2, it must be rotated by approximately 90° about the transverse axis C-C in accordance with the arrow directions shown in Figure 3c, so that the bearing bush 2 is aligned with respect to the bearing shell 3 or the recess 33 of the bearing shell 3 in accordance with Figure 3b. In this position, the bearing bush 2 is inserted in the direction of the arrows B into the recess 33 of the bearing shell 3 and brought with its convex spherical bearing surface 22 into contact with the concave spherical bearing surface 31 of the bearing shell 3 in the upper half of the spherical bearing.

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In this position of the bearing bush 2 in relation to the bearing shell 3 shown in Figure 3a, the bearing bush 2 is pivoted by 90° about the transverse axis 9, so that the lower convex spherical bearing surfaces of the bearing bush 2 also come into contact with the concave spherical bearing surfaces of the bearing shell 3 outside the recess 3 3. In this position, the bearing bush 2 is ready to receive the rudder shaft 1 according to Figure 1 and is secured against falling out by the lower convex spherical bearing surfaces of the bearing bush 2 coming into contact with the concave spherical bearing surfaces of the bearing shell 3.

To prevent the bearing bush 2 from falling out of the bearing shell 3 in this position before inserting the bearing shaft 1 as a result of unintentional rotation of the bearing bush 2 about the transverse axis 9 of the spherical bearing, so that the transversely positioned bearing bush 2 is aligned with the recess 33 of the bearing shell, the locking ring 6 is fastened to the bearing housing 4 or to the bearing shell 3.

To disassemble the spherical bearing according to the invention, the assembly steps described above with reference to Figure 3 are carried out in reverse order and the bearing bush 2 is removed from the bearing shell 3 while aligned with the recess 3 3 of the bearing shell 3 with the locking ring 6 previously removed.

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Claims (9)

BKM107 Page 11 Claims 1. Spherical bearing for a rudder shaft with a spherical layer-shaped bearing bush, through the cover surfaces of which the rudder shaft is guided in the longitudinal direction of the bearing and the convex spherical bearing surface of which is arranged in a concave spherical bearing surface of a bearing shell, characterized, that the bearing shell (3) has a recess (33) running in the longitudinal direction of the bearing, the depth (T) of which is a function of the maximum diameter (D) of the bearing bush (2) and the cross section of which essentially corresponds to the longitudinal section of the bearing bush (2). 2. Spherical bearing according to claim 1, characterized in that the depth (T) of the recess (33) is equal to the vertical distance of the maximum diameter of the bearing bush (2) from one of the two cover surfaces (25) of the bearing bush (2). 3. Spherical bearing according to claim 1 or 2, characterized in that the depth (T) of the recess (33) is greater than or equal to half the height (H) of the bearing bush (2). - 12 - BKM107 Page 12 4. Spherical bearing according to one of the preceding claims, characterized in that the recess (33) in the bearing shell (3) is provided in the cover surface (35) of the bearing shell (3) facing the rudder blade. 5. Spherical bearing according to one of the preceding claims, characterized in that at least one securing element can be fastened to the cover surface (35) of the bearing shell (3) having the recess (33), which reduces the cross section of the recess (33) in the region of the cover surface (35). 6. Spherical bearing according to claim 5, characterized in that the securing element consists of a securing ring (6) connected to the bearing shell (3). 7. Spherical bearing according to one of the preceding claims, characterized in that the part of the recess (33) which is not occupied by the bearing bush is provided with a supplementary element. 8. Spherical bearing according to claim 7, characterized in that the supplementary element consists of a spherical wedge. - 13 - 9. Spherical bearing according to one of the preceding claims, characterized in that the bearing shell (3) is arranged in a bearing housing (4) connected to the ship's hull (5).