Rotor shaft unit

Abstract

A rotor shaft unit for a tidal system, which tidal system includes a main frame and a rotor and a housing connected to the rotor, includes a rotor shaft configured to be connected to the main frame, at least one bearing unit for rotatably supporting the housing for rotation relative to the rotor shaft, and a sleeve configured to be mounted in the main frame, the sleeve being disposed around a first end portion of the rotor shaft and connected to the rotor shaft by a friction connection. Also a tidal system including the rotor shaft unit.

Claims

1. A rotor shaft unit for a tidal system, the tidal system having a main frame having an opening, a rotor, and a housing connected to the rotor, the rotor shaft unit comprising: a rotor shaft configured to support the rotor and the housing, the rotor shaft having a first end portion configured to be received in the opening of the main frame, at least one bearing unit for rotatably supporting the housing for rotation relative to the rotor shaft, and a sleeve configured to be mounted in the opening of the main frame in a rotationally fixed manner and to receive the first end portion of the rotor shaft and be connected to the first end portion of the rotor shaft by a friction connection.

2. The rotor shaft unit according to claim 1, wherein the friction connection between the first end portion of the rotor shaft and the sleeve is produced by a tapered seat.

3. The rotor shaft unit according to claim 1, wherein an outer circumference of the first end portion of the rotor shaft and/or an inner bore of the sleeve is conical.

4. The rotor shaft unit according to claim 1, including a hydraulic nut for biasing the rotor shaft relative to the sleeve to generate the friction connection.

5. The rotor shaft unit according to claim 1, including an oil groove a) formed in the shaft and open toward the sleeve or b) formed in the sleeve and open toward the shaft.

6. The rotor shaft unit according to claim 1, including at least one seal unit disposed around the rotor shaft and configured to seal the bearing unit toward the main frame, wherein the seal unit is disposed between the housing and the main frame.

7. The rotor shaft unit according to claim 6, wherein the seal unit is exchangeable.

8. The rotor shaft unit according to claim 7, wherein the seal unit includes a plurality of seal carrier rings, and wherein each seal carrier ring includes a seal lip.

9. The rotor shaft unit according to claim 8, wherein the seal carrier rings are individually exchangeable.

10. The rotor shaft unit according to claim 1, wherein the first end of the rotor shaft has an outer diameter that decreases in a first direction and wherein an inner diameter of the sleeve decreases in the first direction.

11. A tidal system comprising: a main frame; a rotor; a housing connected to the rotor, and the rotor shaft unit according to claim 1, wherein the sleeve is mounted in the opening of the main frame, wherein the first end portion of the rotor shaft is mounted in the sleeve, and wherein a second end portion of the rotor shaft supports the at least one bearing unit.

12. The tidal system according to claim 11, wherein an outer circumference of the rotor shaft and/or an inner bore of the sleeve is conical, and including a hydraulic nut biasing the shaft against to the sleeve.

13. The tidal system according to claim 12, including a seal assembly mounted around the rotor shaft axially between the housing and the main frame.

14. The rotor shaft unit according to claim 1, wherein the first end portion of the rotor shaft is rotationally fixed in the opening.

15. A tidal system comprising: a main frame including an opening; a sleeve mounted in the opening, the sleeve having an inner surface, the inner surface having a diameter decreasing in a first direction; a rotor and a housing attached to the rotor, a rotor shaft having a first end mounted in the sleeve and a second end extending into the housing, the first end having an outer surface, the outer surface of the first end having a diameter decreasing in the first direction, at least one bearing supporting the housing on the second end of the rotor shaft for rotation relative to the rotor shaft, and means for biasing the rotor shaft relative to the sleeve to hold the outer surface of the first end against the inner surface of the sleeve to increase friction between the outer surface of the first end and the inner surface of the sleeve.

16. The tidal system according to claim 15, wherein the means for biasing comprises a hydraulic nut.

17. The tidal system according to claim 15, wherein the rotor shaft the sleeve and the at least one bearing support form a rotor shaft unit.

18. The tidal system according to claim 15, wherein the sleeve is rotationally fixed relative to the main frame.

19. The tidal system according to claim 18, wherein the rotor shaft is rotationally fixed relative in the sleeve.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) FIG. 1 is a longitudinal section of a rotor shaft unit according to an embodiment of the present disclosure.

DETAILED DESCRIPTION

(2) In the following, identical or functionally equivalent elements are designated by the same reference numbers.

(3) FIG. 1 shows a longitudinal section of a rotor shaft unit 1 for a tidal system. The rotor shaft unit 1 includes a rotor shaft 2 that is supported in housing 4 via bearing units 6. The housing 4 is connected to a rotor 8 of the tidal system. The rotor shaft 2 is stationary and attached to a main frame 10 of the tidal system. In order to permit a simple and flexible attachment of the rotor shaft 2 to the main frame 10, a sleeve 12 is disposed in a bore of the main frame 10. The rotor shaft 2 is pushed into this sleeve 12, and the sleeve 12 and the rotor shaft 2 are connected to each other by a friction connection. In the embodiment shown here the friction connection is realized by a tapered seat.

(4) As depicted in FIG. 1, the outer circumference of the rotor shaft 2 and the inner diameter of sleeve 12 each have a conical shape. Other shapes are also possible. A hydraulic nut 14 is provided for attaching the sleeve 12 and the rotor shaft 2 to each other. This hydraulic nut 14 additionally serves to secure the sleeve 12 axially.

(5) To attach the rotor shaft 2 to the main frame 10, the sleeve 12 is first pushed into the main frame 10. The rotor shaft 2 is then pushed into sleeve 12. The hydraulic nut 14 is then acted upon by a pressure, wherein the pressure presses the sleeve 12 toward the rotor shaft 2, i.e., leftward in the FIGURE. In this way the friction connection is produced between the rotor shaft 2 and the sleeve 12. Here the sleeve 12 is pushed again somewhat out of the main frame 10.

(6) The sleeve 12 has an outer circumference that is cylindrical and is disposed in the bore of the main frame 10. Pushing the sleeve 12 onto the rotor shaft 2 expands the sleeve to a degree and thereby also seats the sleeve firmly in the main frame 10 due to a friction connection.

(7) A seal unit 16 is provided between the sleeve 12 and the housing 4 for sealing the bearing units 6. This seal unit includes a plurality of seal carrier rings 18 that each include a seal lip 20. The seal lips 20 slip on a disc 22 that is disposed around the rotor shaft 2. Alternatively the seal disc 22 can also be implemented by the rotor shaft 2 itself (that is, the seal lips 20 can slip directly on a portion of the rotor shaft 2). When the rotor shaft 2 is pushed into sleeve 12, the sleeve 12 presses against the seal unit 16 or against a protective anode 24 that is disposed on the seal unit 16. Due to the presence of the sleeve 12 the seal unit 16 is also additionally secured in the axial direction, since due to the axial pressure of the hydraulic nut 14 the sleeve 12 abuts against the seal unit 16.

(8) To assemble the entire rotor shaft unit 1, the bearing units 6 and the housing 4, as well as the associated seal units 6, are first attached to the rotor shaft 2. The rotor shaft 2 is then attached as entire rotor shaft unit 1 to the main frame 10 by pushing the rotor shaft 2 into the sleeve 12.

(9) To remove the rotor shaft unit 1 from the main frame 10, an oil groove 26 (in FIG. 1 implemented in the sleeve 12) can be provided in the rotor shaft 2 or in the sleeve 12, or in both. Oil can be introduced in the oil groove 26 in order to generate a sliding film in the region 28 between the sleeve 12 and the rotor shaft 2. This sliding film allows the friction connection between the rotor shaft 2 and the sleeve 12 to be released, and the rotor shaft 2 can thus be easily removed from the sleeve 12. Removing the rotor shaft 2 in this manner also permits a simple access to the seal unit 16 in order to exchange the seal unit 16 as a whole, or to exchange individual seal carrier rings or seal lips 20.

(10) The rotor shaft unit disclosed herein allows for a simple installation and removal of a rotor shaft unit onto a main frame of a generator. Furthermore, the manufacturing of the rotor shaft is simplified because no flange needs to be produced thereon for attaching to the main frame.

(11) Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Furthermore, each of the additional features and teachings disclosed above may be utilized separately or in conjunction with other features and teachings to provide improved rotor shaft units.

(12) Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention. Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings.

(13) All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter.

REFERENCE NUMBER LIST

(14) 1 Rotor shaft unit 2 Rotor shaft 4 Housing 6 Bearing units 8 Rotor 10 Main frame 12 Sleeve 14 Hydraulic nut 16 Seal unit 18 Seal carrier rings 20 Seal lip 22 Seal disc 24 Protective anode 26 Oil groove 28 Region between sleeve and rotor shaft