Patent Application
20250101945
This application claims priority from German Patent Application No. 10 2023 209 290.5, filed on Sep. 22, 2023, the entire content of which is incorporated herein by reference in their entirety.
The present invention relates to a hydraulic system for a rotor brake of a wind turbine. Furthermore, the present invention relates to a rotor brake with such a hydraulic system and with a brake caliber. In addition, the present invention also relates to a wind turbine with a rotor brake according to the invention.
Known wind turbines are usually equipped with a rotor brake. During maintenance of the wind turbine, the brake is applied in order to prevent unwanted and therefore possibly dangerous movement of the wind turbine rotor. For this purpose, the rotor brake regularly has at least one brake caliber, which usually acts on a brake disc arranged on the generator shaft in order to lock the generator shaft.
The use of a hydraulic system has proven itself for applying the rotor brake. These hydraulic systems known from the state of the art have a hydraulic unit and the pressure relief valves, pressure switches and changeover valves required for this purpose to supply pressure to the rotor brake. The operating pressure of the rotor brake is provided by operating the hydraulic unit in an accumulator charging mode. Once the maintenance process is complete, the hydraulic unit is switched off so that the rotor brake is released. Such a hydraulic system is known, for example, from DE 10 2007 002 137 A1. DE 10 2017 102 375 B3 discloses a hydraulic system with a manually operable emergency pump.
These well-known solutions work reliably and can be easily operated by a maintenance technician. However, the disadvantage of the known solution is the high number of relatively expensive components. It is desirable to provide a significantly more cost-effective solution, particularly in view of the reduced time required to use the hydraulic unit.
It is therefore the object of the present invention to provide a more cost-effective hydraulic system for a rotor brake of a wind turbine.
The solution to the problem is achieved with a hydraulic system for a rotor brake of a wind turbine according to claim 1. Preferable further embodiments are described in the dependent claims.
The hydraulic system according to the invention for a rotor brake of a wind turbine has a manually operable pump device and a connection for connecting to the rotor brake. The manually operable pump device is connected to the connection. This avoids the need for an expensive hydraulic unit. Instead, the required operating pressure of the rotor brake is provided by an inexpensive manually operable pump device. According to the present disclosure, the manually operable pump device comprises a coupling section for actuation, wherein the coupling section can be coupled to an external device. In other words, the coupling section is configured to be coupled to an external device. The maintenance technician can thus actuate the pump device using the external device coupled to the coupling section and may thus generate the necessary operating pressure.
A connection in the sense of the invention does not necessarily mean a single connection. Rather, it can also mean several connections and further supply lines, for example connection options for leakage lines or the like.
Another advantage of the hydraulic system is that it has a tank chamber, with the tank chamber being connected to the manually operable pump device. The tank chamber can be used, for example, to compensate for temperature fluctuations.
The hydraulic system according to the invention preferably has a first bypass line, wherein the first bypass line connects the connection to the tank chamber, bypassing the manually operable pump device. A first closing valve can be disposed in the first bypass line. In particular, the first closing valve can be a pressure relief valve or a shut-off valve.
A closing valve configured as a pressure relief valve can be used to provide protection in the event of excess pressure. If the closing valve is configured as a manually openable shut-off valve, the maintenance technician can directly regulate the pressure applied to the connection, for example to compensate for temperature fluctuations.
Here, it is preferable if the hydraulic system has a second bypass line, wherein the second bypass line connects the connection to the tank chamber, bypassing the manually operable pump device. A second closing valve can be disposed in the second bypass line. Preferably, the second closing valve is either a pressure relief valve or a preferably manually openable shut-off valve and is different from the first closing valve. In other words, if the first closing valve in a preferred embodiment is configured as a pressure relief valve, the second closing valve is configured as a shut-off valve.
Preferably, the hydraulic system is configured as a cartridge. This design as a screw-in cartridge makes the hydraulic system particularly easy to install and integrate.
Preferably, the hydraulic system is hydraulically preloaded, preferably via a spring preload integrated in the manually operable pump device or in an integrated hydraulic accumulator. This allows temperature fluctuations and minor leaks in the brake caliber to be compensated for directly. It is conceivable that the tank chamber is configured as a hydraulic accumulator.
Preferably, the external device to be connected to the coupling section is a tool or an external motor. The maintenance technician can thus actuate the pump device using a tool and generate the necessary operating pressure. The tool can, for example, also be disposed on a cordless screwdriver or the like. It is also conceivable to use an external motor to provide the operating pressure via the manually operable pump device. This results in a hydraulic system that is particularly easy to actuate in order to provide the operating pressure required to apply the brake.
Preferably, the manually operable pump device has pressure chamber, a housing, a drive shaft and a piston element, wherein the pressure chamber is at least partially formed by the housing. The piston element is movably disposed in the pressure chamber and the drive shaft is rotatably mounted relative to the housing and connected to the piston element, wherein rotation of the drive shaft moves the piston element linearly or axially in the pressure chamber and thus relative to the housing. When the maintenance technician turns the drive shaft, the piston element moves linearly in the pressure chamber in order to generate the necessary operating pressure.
Preferably, the piston element is guided inside the housing in such a way that the piston element is prevented from rotating relative to the housing. The drive shaft can therefore be rotated relative to the housing, but cannot be moved axially or linearly. A rotational movement of the drive shaft is therefore transmitted to the piston element via a suitable interface, for example via a threaded connection between the drive shaft and the piston element.
Alternatively, it might be preferable if the drive shaft is axially movable relative to the housing and moves together with the piston element. When the drive shaft rotates, it therefore moves axially relative to the housing so that it is a rising drive shaft. This has the advantage that a separate bearing to support the rotary movement of the drive shaft, for example a roller bearing or plain bearing, is not necessary.
A fully integrated hydraulic system configured in this way can be arranged directly on the brake caliber or used as a stand-alone solution.
Preferably, the piston element has a first piston part, a second piston part and a preload element, wherein the first piston part is connected to the drive shaft and wherein the second piston part is connected to the first piston part via the preload element. A hydraulic preload of the hydraulic system can be achieved via the preload element, for example to compensate for minor leaks in the brake caliber or temperature fluctuations.
Preferably, the manually operable pump device has a locking element that can be moved between a release position and a locking position. In the locking position, the locking element secures the drive shaft against rotation relative to the housing. In the release position of the locking element, the drive shaft can be rotated relative to the housing. By moving the locking element from the release position to the locking position, the maintenance technician can safely prevent further rotation of the drive shaft and thus also a change in the operating pressure.
Alternatively, it the manually operable pump device may be a gear pump with a drive shaft, wherein the coupling section is disposed on the drive shaft. Preferably, the coupling section is disposed at an axial end of the drive shaft of the gear pump.
Due to possible leakage occurring at the gear pump, a manually unlockable non-return valve may be disposed between the gear pump and the connection. The manually unlockable non-return valve prevents a backflow from the connection to the gear pump, so that a pressure is locked between the non-return valve and the connection or a brake caliber connected to the connection and thus the brake caliber is held in the extended position. To retract the brake caliber, the manually unlockable non-return valve is manually unlocked.
Preferably, the hydraulic system has a manually operbable lever mechanism for unlocking the non-return valve. For example, the lever mechanism may be configured as a button or lever.
It is particularly preferable if the manually operable lever mechanism is connected to the drive shaft of the gear pump, whereby an axial movement of at least part of the drive shaft actuates the lever mechanism and unlocks the non-return valve. For example, the maintenance technician can use an external device attached to the coupling section to move the entire drive shaft or part of the drive shaft axially, for example by pushing it in. This unlocks the non-return valve and a rotation of the drive shaft pressurizes the connection or relieves the connection, depending on the direction of rotation.
Preferably, the manually operable pump device is a reversible manually operable pump device. This makes it possible to reduce the operating pressure applied to the connection by reversing the direction of rotation of the drive shaft.
The invention also relates to a rotor brake for a wind turbine, wherein the rotor brake has at least one brake caliber and a hydraulic system according to the invention as described above, wherein the brake caliber is hydraulically connected to the connection of the hydraulic system. Furthermore, the invention relates to a wind turbine with such a rotor brake.
The invention is explained in more detail below with reference embodiments shown in the drawings.
In order to prevent the rotor 106 from starting up again during maintenance of the wind turbine 100, which can be dangerous under certain circumstances, it can be locked by means of a rotor brake 1.
The hydraulic system 10, a tank chamber 30, a manually operable pump device 12 with a pressure chamber 11 and a connection 13. During maintenance of the wind turbine 100, the maintenance technician can generate the necessary operating pressure of the rotor brake 1 via the manually operable pump device 12. For this purpose, the brake caliber 2 is connected to the connection 13 of the hydraulic system 100 via a line 3 in a known manner.
Furthermore, the hydraulic system 10 has a first bypass line 14 with a first closing valve 15 configured as a pressure relief valve. Furthermore, the hydraulic system 10 can have a second bypass line 16 with a second closing valve 17 configured as a shut-off valve. The first bypass line 14 and the second bypass line 16 each connect the connection 13 directly to the tank chamber 30, bypassing the manually operable pump element 12. The pressure relief valve 15 protects the hydraulic system 10 in the event of an excess pressure. The shut-off valve 17 is configured as a manually openable shut-off valve so that the maintenance technician can reduce the pressure applied to the brake caliber 2 if necessary, for example in the event of temperature fluctuations.
As shown, the connection 13 is formed on an axial end face of the housing 18 and the line 3 is secured to the connection 13 by screwing, for example. Of course, the line 3 can also be secured to the connection 13 in another way.
The drive shaft 19 is rotatably supported on the housing 18 via at least one bearing 24, wherein the drive shaft 19 is not axially movable relative to the housing 18. For this purpose, the housing 18 can, for example, have an intermediate plate 25, on which the drive shaft 19 is axially supported via a circumferential ring 31 (which can be centered via the bearing 24) and is thus secured against axial movement or axial drift. Of course, the drive shaft 19 can also be secured against axial movement in other ways.
The drive shaft 19 is connected to the piston element 20 in such a way that a rotary movement of the drive shaft 19 is converted into a linear movement of the piston element 20. In the embodiment example shown, the drive shaft 19 is connected to the first piston part 21 via a threaded connection 26. The first piston part 21 is guided within the housing 18 in such a way that rotation of the first piston part 21 relative to the housing 18 is prevented. This can be achieved, for example, by means of a groove guide (not shown). Of course, other anti-rotation devices are also conceivable.
By rotating the drive shaft 19, the first piston part 21 is moved relative to the drive shaft 19 and therefore to the housing 18 due to the threaded connection 26. The linear movement of the first piston part 21 is transferred to the second piston part 22 via the preload element 23 and the volume of the pressure chamber 11 is thus increased or reduced depending on the direction of rotation of the drive shaft 19. The manually operable pump element is therefore a reversible manually operable pump element. By reversing the direction of rotation of the drive shaft 19, the operating pressure at the connection 13 can be reduced.
Alternatively, the drive shaft 19 can also be configured to rise. The drive shaft 19 is then rigidly connected to the piston element 20 or the first piston part 21 and moves axially and relative to the housing 18 during rotation. This has the advantage that the bearing 24 can be omitted and the first piston part 21 does not have to be secured against rotation.
A coupling section 27 is disposed at the axial end of the drive shaft 19 opposite the threaded connection 26. An external device, for instance a suitable tool, can engage the coupling section 27 in order to rotate the drive shaft 19. For example, the coupling section 27 can be configured as a hexagon so that the maintenance technician can actuate the manually operable pump element 12 using a cordless screwdriver with a corresponding nut, for example. However, other types of actuation via other external devices are of course also conceivable, for example via a foot or hand lever that can be coupled or via an external motor.
Furthermore, the manually operable pump element 12 has a locking element 28. The locking element 28 can be moved between a release position and a locking position. In the release position of the locking element 28, the drive shaft 19 can be rotated and the manually operable pump element 12 can be actuated. In the locking position, the locking element 28 blocks a rotary movement of the drive shaft 19 so that the operating pressure currently applied to the connection 13 cannot be changed. In the exemplary embodiment shown, the locking element 28 is configured as a locking pin, which is movable within the intermediate plate 25 in such a way that rotation of the drive shaft is blocked in the locking position. Of course, other configurations are also conceivable, for example via a switching disk that can be switched via a switching lever, which blocks rotation in one direction in each case depending on the position of the switching lever.
As also shown in
A through bore 33 is formed in the first piston part 21, which communicates with an additional connection 34 on the housing. An additional tank (not shown) can be provided at the additional connection 34 in order to provide a sufficient volume of the tank chamber 30 if required.
The operating pressure is generated at connection 13 by moving the piston element 20 via the drive shaft 19. Any excess pressure can be relieved directly via the pressure relief valve 15. Hydraulic fluid can be sucked in via the non-return valve 32.
The exemplary embodiment shown in
Furthermore, the hydraulic system 10 has a first bypass line 14 with a first closing valve 15 configured as a pressure relief valve. The first bypass line 14 connects the connection 13 directly to the tank chamber 30, bypassing the manually operable pump element 12. The pressure relief valve 15 protects the hydraulic system 10 of excess pressure.
In this embodiment, the manually operable pump element 12 is configured as a reversible gear pump with a drive shaft 51. The coupling section 27 is dispsoed at the axial end of the drive shaft 51 of the gear pump 12, so that a maintenance technician can connect a suitable external device, for example a cordless screwdriver, to actuate the gear pump 12 by rotating the drive shaft 51, as already described above for the first embodiment.
A manually unlockable non-return valve 52 is dispsoed between the gear pump 12 and the connection 13. The non-return valve 52 opens in the direction of flow to the connection 13 and prevents pressure applied to the brake caliber 2 from being gradually reduced via the leaky gear pump 12. To retract the brake caliber 2, the manually unlockable non-return valve 52 is unlocked by the maintenance technician.
The hydraulic system 50 has a manually operable lever mechanism 53 for this purpose. In the embodiment example shown in
An alternative embodiment of the lever mechanism 53 is shown in
The hydraulic system 50 described with reference to
Finally, it should be noted that the numerals used here, such as “first” or “second”, do not specify a concrete order, but merely serve to differentiate between elements.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2023 209 290.5 | Sep 2023 | DE | national |
