Abstract
The invention relates to a bearing for supporting a shaft, in particular a rudder shaft, or a rudder blade, by means of which bearing the bearing clearance or the bearing wear can be continuously monitored, determined, and optionally documented. According to the invention, for a bearing for supporting a shaft, in particular a rudder shaft, comprising a first bearing element and a second bearing element, wherein the first bearing element has a sliding surface for contacting the second bearing element in a sliding manner, and a measurement-value sensor having a wear surface for contacting the second bearing element in a sliding manner, the at least one measurement-value sensor is not pin-shaped.
Claims
1. A bearing for supporting a rudder shaft or a rudder blade, comprising a first bearing element and a second bearing element, wherein the first bearing element has a sliding surface for contacting the second bearing element in a sliding manner, and at least one measurand sensor having a wear surface for contacting the second bearing element in a sliding manner, wherein the at least one measurand sensor is not pin-shaped.
2. The bearing according to claim 1, wherein the wear surface of the measurand sensor is formed in a manner corresponding to a portion of the lateral surface of a cylinder or a cone.
3. The bearing according to claim 1 or claim 2, wherein a measurand sensor receptacle or a recess is arranged in the sliding surface of the first bearing element, wherein the at least one measurand sensor is arranged in the measurand sensor receptacle or the recess, and in that the measurand sensor can be inserted into the measurand sensor receptacle and/or can be removed from the measurand sensor receptacle exclusively from the side of the sliding surface.
4. The bearing according to claim 1, wherein the first bearing element is a bearing bush, and/or wherein the first bearing element can be arranged on the inner side of a trunk pipe of a rudder trunk, and/or wherein the first bearing element can be arranged on the outer side of the trunk pipe of the rudder trunk, and/or wherein the second bearing element can be arranged on a rudder shaft or can be formed as part of a rudder shaft, and/or wherein the second bearing element can be arranged on a rudder blade of a rudder, and/or wherein the bearing can be arranged between the trunk pipe and the rudder shaft, and/or wherein the bearing can be arranged between the trunk pipe and the rudder blade.
5. The bearing according to claim 1, wherein the measurand sensor has an electrically conductive material, wherein the electrically conductive material is arranged in the region of the wear surface in order to measure the wear of the measurand sensor.
6. The bearing according to claim 5, wherein the electrically conductive material is formed as at least two layers and/or is formed as at least two conductor circuits and/or as at least two conductor paths, wherein, in an unworn state of the measurand sensor, the at least two layers or conductor layers and/or the at least two conductor circuits and/or the at least two conductor paths are electrically insulated from each other.
7. The bearing according to claim 6, wherein the at least two layers or conductor layers and/or conductor circuits and/or conductor paths are arranged at a different distance from the wear surface, and/or wherein the at least two layers or conductor layers and/or conductor circuits and/or conductor paths are arranged adjacently to each other.
8. The bearing according to claim 5, wherein the measurand sensor comprises a control unit, wherein the control unit is designed to detect wear of the measurand sensor by measuring the change in electrical resistance and/or by measuring a short circuit between two layers and/or conductor circuits and/or conductor paths which are electrically insulated from one another in the unworn state of the measurand sensor.
9. The bearing according to claim 5, wherein the electrically conductive material is arranged in a carrier, and/or wherein the electrically conductive material and/or the carrier is arranged or molded in a non-metal material.
10. The bearing according to claim 3, wherein an opening passing through the first and/or the second bearing element is formed in a wall and/or side wall of the measurand sensor receptacle or of the recess, and wherein a signal conduction means, of the measurand sensor is guided through the opening.
11. A bearing clearance measuring device for measuring the bearing clearance of a bearing of a rudder shaft or of a rudder blade, comprising a bearing for supporting a rudder shaft, or a rudder blade, said bearing comprising a first bearing element and a second bearing element, wherein the first bearing element has a sliding surface for contacting the second bearing element in a sliding manner, and said bearing comprising at least one measurand sensor having a wear surface for contacting the second bearing element in a sliding manner, wherein the at least one measurand sensor is not pin-shaped, wherein the bearing clearance measuring device comprises a computing unit which is designed to receive and to process signals and/or information of the at least one measurand sensor.
12. A rudder for a ship comprising a rudder shaft and a rudder blade arranged on the rudder shaft, wherein the rudder comprises a bearing for supporting the rudder shaft or the rudder blade, comprising a first bearing element and a second bearing element, wherein the first bearing element has a sliding surface for contacting the second bearing element in a sliding manner, and at least one measurand sensor having a wear surface for contacting the second bearing element in a sliding manner, wherein the at least one measurand sensor is not pin-shaped, and/or wherein the rudder comprises a bearing clearance measuring device for measuring the bearing clearance of a bearing of a rudder shaft or of a rudder blade, comprising a bearing for supporting a rudder shaft or a rudder blade, said bearing comprising a first bearing element and a second bearing element, wherein the first bearing element has a sliding surface for contacting the second bearing element in a sliding manner, and said bearing comprising at least one measurand sensor having a wear surface for contacting the second bearing element in a sliding manner, wherein the at least one measurand sensor is not pin-shaped, wherein the bearing clearance measuring device comprises a computing unit which is designed to receive and to process signals and/or information of the at least one measurand sensor.
13. The rudder according to claim 12, wherein the rudder has a rudder trunk comprising a trunk pipe, wherein the bearing is arranged between the trunk pipe and the rudder shaft, and/or wherein the bearing is arranged between the trunk pipe and the rudder blade, and/or wherein the trunk pipe has a guide means on the outside or the inner side and wherein a signal conduction means of the measurand sensor is arranged in the guide means in such a way that signals and/or information can be conducted or transferred between the measurand sensor and a computing unit.
14. The rudder according to claim 13, wherein a spacer is provided, wherein the spacer can be attached to the inner side of the trunk pipe, such that damage to the measurand sensor during insertion of the rudder shaft into the trunk pipe of the rudder trunk can be avoided.
15. A method for measuring a bearing clearance and/or a wear of a bearing for a rudder shaft, or for a rudder blade, wherein at least one non-pin-shaped measurand sensor having at least two layers and/or conductor circuits and/or conductor tracks made of an electrically conductive material is arranged in a bearing for supporting a rudder shaft, or a rudder blade, wherein the electrical resistance of the at least two layers and/or conductor circuits and/or conductor paths is measured, and wherein a bearing clearance and/or a wear of the bearing is determined when a change in the electrical resistance at least of one of the two layers and/or conductor circuits and/or conductor paths is measured, and/or wherein a bearing clearance and/or wear is determined when a short circuit between two of the layers and/or conductor circuits and/or conductor paths is measured.
16. The method according to claim 15, wherein measured values and/or jumps in the measured values of the electrical resistance and/or a short circuit are stored, and/or wherein at least one layer and/or a conductor circuit and/or a conductor path made of an electrically conductive material is severed before the measurand sensor is arranged in the bearing, and wherein a reference measurement and/or test measurement of the electrical resistance and/or a short circuit is taken.
17. The bearing according to claim 5, wherein the electrically conductive material is formed as at least one layer or conductor layer and/or at least one conductor circuit and/or at least one conductor path.
18. The bearing according to claim 7, wherein the conductor paths are arranged adjacently to each other at a distance of 100 m to 1000 m.
19. The bearing according to claim 9, wherein the carrier is a circuit board or a printed circuit board.
20. The bearing according to claim 10, wherein the signal conduction means is an electrical line or cable.
Description
BRIEF DESCRIPTIONS OF THE DRAWINGS
(1) Exemplary embodiments of the invention will be explained in greater detail hereinafter on the basis of the drawings, in which:
(2) FIG. 1 in a side view shows the stern of a ship with a bearing for supporting a rudder shaft,
(3) FIG. 2 in a rear view shows the stern of a ship with a bearing for supporting a rudder shaft,
(4) FIG. 3 in a side view shows the lower end portion of a rudder trunk and rudder shaft with a bearing,
(5) FIG. 4 in a cross-sectional view shows the lower end region of a rudder trunk and rudder shaft with a bearing,
(6) FIG. 5 shows a measurand sensor with a wear surface,
(7) FIG. 6 in a side view shows the lower end region of a rudder trunk with a bearing and a measurand sensor,
(8) FIG. 7 in a cross-sectional view shows the lower end region of a rudder trunk with a bearing and a measurand sensor,
(9) FIG. 8 in a side view shows a rudder trunk with a cable channel,
(10) FIG. 9 is a side view shows the lower end region of a rudder trunk with a bearing bush and a segmented ring,
(11) FIG. 10 in a cross-sectional view shows the lower end region of a rudder trunk with a bearing bush and a segmented ring,
(12) FIG. 11 shows a two-part bearing bush with a segmented ring,
(13) FIG. 12 shows a two-part bearing bush with a segmented ring,
(14) FIG. 13 shows a one-part bearing bush with a segmented ring,
(15) FIG. 14 shows a measurand sensor with a wear surface in a worn state,
(16) FIG. 15 shows a measurand sensor with an elongate design.
PREFERRED EMBODIMENT OF THE INVENTION
(17) FIGS. 1 and 2 show the stern 10 of a ship 11 comprising a bearing 100 for supporting a rudder shaft in a side view and in a rear view. Behind a propeller 12, as viewed in the direction of travel, there is arranged a rudder 13 comprising a rudder blade 14. In FIG. 2 the propeller is indicated by the propeller circle K, over which the propeller blades travel. The rudder blade 14 is arranged on a rudder shaft 17 mounted rotatably in a trunk pipe 15 of a rudder trunk 16. The rudder shaft 17 is drawn deep into the rudder blade 14. The trunk pipe 15 of the rudder trunk 16 is fixedly connected to the ship's hull 18. In a vertical direction, the rudder shaft 17 is secured above the trunk pipe 15 by means of a supporting bearing 19 formed as an axial bearing. The rudder shaft 17 is connected via an upper end region 20 to a rudder engine 21. The rudder shaft 17 is supported on the trunk pipe 15 of the rudder trunk 16 via a journal bearing 23 arranged at a lower end region 22 of the rudder shaft 17. The journal bearing 23 is disposed in the peripheral direction of the rudder shaft 17 running between the rudder shaft 17 and the inner side 24 of the trunk pipe 15 of the rudder trunk 16. A further journal bearing could be provided optionally in order to support the upper end region 20 of the rudder shaft 17.
(18) FIG. 3 shows an enlarged illustration of the rudder trunk 16 and of the lower end region 22 of the rudder shaft 17. A first bearing element 26 formed as a bearing bush 25 is arranged between the inner side 24 of the trunk pipe 15 of the rudder trunk 16 and the rudder shaft 17. The first bearing element 26 has a sliding surface 27 for contacting a second bearing element 28 in a sliding manner. The second bearing element 28 is formed in the illustrated embodiment as part of the rudder shaft 17. Measurand sensors 29 are arranged recessed in recesses 30 or measurand sensor receptacles 30a in the bearing bush 25. The measurand sensors have wear surfaces 31.
(19) FIG. 4 shows a section through the trunk pipe 15 of the rudder trunk 16 along the line of section A-A in FIG. 3. The first bearing element 26 formed as a bearing bush 25 is arranged on the inner side 24 of the rudder trunk 16 and is arranged with the sliding surface 27 contacting the rudder shaft 17 in a sliding manner. Measurand sensors 29 are arranged in recesses 30 formed for this purpose in the bearing bush 25 at regular distances in the peripheral direction of the bearing bush 25. The measurand sensors 29 each have a wear surface 31, via which the measurand sensors 29 are arranged in contact with the rudder shaft 17 in a sliding manner. The wear surface 31 of each measurand sensor 29 extends in line or flush with the sliding surface 27 of the bearing bush 25. In particular, the wear surface 31 does not protrude radially inwardly beyond the sliding surface 27 of the bearing bush 25. In the illustrated embodiment the measurand sensors 29 are distributed at regular angular intervals over the periphery of the bearing bush 25. However, embodiments are also conceivable in which the distances are irregular.
(20) FIG. 5 shows a cross-section through a measurand sensor 29. The measurand sensor 29 has a compact form and in particular is not elongate or pin-shaped. The measurand sensor 29 has a circuit board 32, in which a first conductor path 33 and a second conductor path 34 are integrated. However, more than two conductor paths or conductor path loops can also be provided. Furthermore, a control unit 35 is arranged on the circuit board 32 and is designed to measure the electrical resistance of the first conductor path 33 or of the second conductor path 34 and/or to determine a short circuit between the first conductor path 33 and the second conductor path 34. The first conductor path 33 has an approximately square shape and is disposed in regions at a distance D1 from the wear surface 31 of the measurand sensor 29. The second conductor path 34 likewise has an approximately square shape and is arranged in regions at a distance D2 from the wear surface 31. The second distance D2 is greater here than the first distance D1. The difference between the distances D1 and D2 is preferably between 100 m and 1000 m, and the distance D1 of the first conductor path 33 from the wear surface 31 is likewise between 100 m and 1000 m. The circuit board 32 comprising the first conductor path 33 and second conductor path 34 and also the control unit 35 is moulded in an electrically non-conductive material, such as synthetic resin 36. The control unit 35 of the measurand sensor 29 is connected to a signal line 37, which exits from the measurand sensor 29 on the side 38 opposite the wear surface 31. The control unit 35 of the measurand sensor 29 can exchange information and data via the signal line 37 with a superordinate computing unit (not illustrated) of the bearing 100 for supporting a shaft or the bearing clearance measuring device 39.
(21) As illustrated in FIGS. 6 and 7, the recess 30 in which the measurand sensor 29 is received is formed in the manner of a slot-shaped groove 40. The groove 40 has the form of a blind bore 41, which does not fully pass through the bearing bush 25. A through-hole 43 is disposed in the bottom 42 of the blind bore 41. A drilled channel 44 is disposed in the trunk pipe 15 of the rudder trunk 16 and is oriented in the direction of the through-hole 43. The signal line 37 of the measurand sensor 29 is guided through the through-hole 43 to the outer side of the trunk pipe 15 of the rudder trunk 16. At least one cable box 46 is arranged on the outer side 45 of the rudder trunk 16, and at least one of the signal lines 37 of the measurand sensor 29 leads into said cable box. The signal lines 37 can be bundled in the cable box 46 and are guided further into a guide means formed as a cable channel 47. The measurand sensor 29 can be inserted into and/or removed from the first bearing element 26 or the bearing bush 25 only from the side of the sliding surface 27. The bottom 42 of the blind bore 41 prevents any play of the measurand sensor 29 in the radial direction of the bearing bush 25. The measurand sensor 29 for this purpose rests against the bottom 42 of the blind bore 41 formed as a contact face.
(22) As illustrated in FIG. 8, the cable channel 47 extends on the outer side of the trunk pipe 15 of the rudder trunk 16 in the vertical direction as far as the upper end region portion 20 of the rudder shaft 17. In addition to the signal lines 37, power lines 48 for supplying power to the measurand sensors 29 and in particular to the control unit 35 arranged on the measurand sensors 29 also run through the cable channel 47. The rudder trunk 16 is fixedly welded to the ship's hull 18. A hull bore 49 is provided in the region of connection of the ship's hull 18 to the trunk pipe 15 of the rudder trunk 16, through which bore the cable channel 47 is guided into the interior of the ship's hull 18. The gap between the hull bore 49 and the cable channel 47 is sealed in a watertight manner.
(23) The operating principle of the bearing clearance measuring device 39 will now be described with reference to FIGS. 4, 5 and 14. The measurand sensor 29 is disposed with the wear surface 31 contacting the rudder shaft 17 in a sliding manner. The surface of the rudder shaft 17 here constitutes the second bearing element 28. As a result of abrasive wear, caused by rotations of the rudder shaft 17 or deflections of the rudder 13, the wear surface 31 of the measurand sensor 29 is abraded layer by layer. As soon as a layer of a thickness corresponding to the first distance D1 of the wear surface 31 has been abraded, the first conductor path 33 is exposed or the first conductor path 33 lies in the wear surface 31. With continued wear, the first conductor path 33 is ground away and interrupted. As soon as the first conductor path 33 is interrupted, the control unit 35 on the circuit board 32 of the first measurand sensor 29 determines a sudden rise of the electrical resistance in the case of a dry bearing. With continued wear, further layers of the synthetic resin 36 of the measurand sensor 29 are rubbed off to a thickness corresponding to the second distance D2, whereupon the second conductor path 34 is also exposed or lies in the wear surface 31. With continued abrasion again, the second conductor path 34 is lastly also rubbed through, and a sudden rise of the electrical resistance of the second conductor path 34 can be determined by the control unit 35. In the case of a dry bearing 23, these jumps in the electrical resistance can be assessed as measured values for abrasion of the measurand sensor 29 and therefore for wear of the bearing bush 25. If, by contrast, a water-lubricated bearing 23 is provided, a severing of the first conductor path 33 or second conductor path 34 cannot be measured with absolute certainty on account of the conductivity of seawater, since the electrically conductive seawater takes on the task of forwarding the electrical current instead of the first conductor path 33 and the second conductor path 34.
(24) For this purpose, the control unit 35 is designed to determine a short circuit between the first conductor path 33 and second conductor path 34. If the wear surface 31 has been abraded by a layer thickness corresponding to the second distance D2 and therefore parts of the first conductor path 33 and the second conductor path 34 are exposed, the end regions 50, 51 of the conductor paths 33, 34 come into electrical contact with one another either by direct contact or by means of the electrically conductive seawater wetting the wear surface 31 and produce a short circuit between the first conductor path 33 and the second conductor path 34. This short circuit can be determined unequivocally by the control unit 35, and the measured value, as measurand, is conducted through the signal line 37 to a superordinate computing unit, which determines the wear of the measurand sensor 29 and therefore of the bearing 23 on the basis of the measured values.
(25) In this respect, FIG. 14 illustrates the case in which the wear surface 31 of the measurand sensor 29 has been rubbed off by abrasive wear to such an extent that the first conductor path 33 and the second conductor path 34 have been exposed or rubbed through. In other words, the wear surface 31 has receded, as a result of wear, outwardly in the radial direction in the direction of the control unit 35, by approximately the layer thickness corresponding to the second distance D2, such that the two end regions 50, 51 of the first conductor path 33 and of the second conductor path 34 lie in the wear surface 31 or border the wear surface 31 or protrude from the wear surface 31, such that the end regions 50, 51 in the case of a water-lubricated bearing come at least partially into contact with seawater wetting the wear surface 31. On account of the electrical conductivity of the seawater, a short circuit is produced between the end regions 50, 51 of the first conductor path 33 and the second conductor path 34, which can be determined by the control unit 35.
(26) FIGS. 9 and 10 illustrate an alternative embodiment of the bearing clearance measuring device 39. The bearing clearance measuring device 39 has a segmented ring 52, which is composed of a number of ring segments 53. A ring segment 53 is formed as a sensor segment 54 and comprises a measurand sensor 29. The segmented ring 52 is arranged in a groove 55 in the bearing bush 25, said groove running around in the peripheral direction. In order to secure the sensor segment 54, clamping segments 56 are provided in the segmented ring 52 which, together with the sensor segments 54, complete the segmented ring 52.
(27) FIGS. 11 and 12 show how the segmented ring 52 is fastened in the bearing bush 25. The bearing bush 25 is for this purpose embodied in two parts and has a first bearing part 57 and a second bearing part 58. The first bearing part 57 and the second bearing part 58 each have, in regions facing toward one another, an L-shaped profile 59 running around in the peripheral direction, which, when the first bearing part 57 and second bearing part 58 are arranged with one another, form an annular groove 55 running around the bearing bush 25 in the peripheral direction. The segmented ring 52 is arranged in the L-shaped profile 59 of the first bearing part 57 and is connected thereto in a watertight manner. The second bearing part 58 is then arranged on the first bearing part 57 in such a way that the segmented ring 52 is arranged in the L-shaped profile 59 of the second bearing part 58. As a result of this arrangement of the first and second bearing part 57, 58, the L-shaped profiles 59 of the first bearing part 57 and the second bearing part 58 together form a groove 55 running around the bearing bush 25 in the peripheral direction, in which groove the segmented ring 52 comprising sensor segments 54 and clamping segments 56 is arranged. The bearing bush 25 can be arranged in the rudder trunk 16 for example by freezing.
(28) FIG. 13 shows a further embodiment of the bearing clearance measuring device 39. In the illustrated embodiment the bearing bush 25 is formed in one part and at one end has an L-shaped profile 59 running around in the peripheral direction, in which the segmented ring 52 can be arranged. In this embodiment the segmented ring 52 comprising the measurand sensor 29 is thus disposed above or below the bearing bush 25 and not centrally in the bearing bush 25 as considered in the axial direction.
(29) FIG. 15 shows a measurand sensor 29 with a substantially elongate design. A wear surface 31 of the measurand sensor 29 is not arranged on one of the end faces 60, or is not arranged on one of the sides, outer sides or planes perpendicular to the direction R of the elongated design. In the embodiment of the measurand sensor 29 according to FIG. 15, this recorder is particularly suitable for being inserted into a measurand sensor receptacle 30a or a recess 30 in the form of a slot-shaped or elongate blind bore 41 or groove 40 or channel or step preferably arranged in the sliding surface 27 in the longitudinal direction of the first bearing element 26. The end faces 60 of the measurand sensor 29 have a rounded course with a radius of curvature R1. The radius of curvature can preferably be between 2 and 20 mm, particularly preferably between 5 and 10 mm. The length L of the measurand sensor 29 in the direction R of the elongate design between the rounded end faces 60 is preferably between 20 and 40 mm, particularly preferably approximately 30 mm. The measurand sensor 29 of FIG. 15 is otherwise identical to the previously described measurand sensors and can also be used in particular in any of the devices shown in FIGS. 2 to 14.
