Hydraulic system for rotor brake, rotor brake and wind turbine

Abstract

The invention relates to a hydraulic system 10 for a rotor brake 1 of a wind turbine, where the hydraulic system 10 has a pressure chamber 11, a manually operable pump device 12 and a connection 13 for connection to the rotor brake 1, where the manually operable pump device 12 is connected to the pressure chamber 11 and the connection 13. The manually operable pump device (12) comprises a coupling portion (27) for actuation, where the coupling portion (27) is configured to be connected to an external device.

Description

Technical Field

[0001] The invention relates to a hydraulic system for a rotor brake of a wind turbine. The invention further relates to a rotor brake having such a hydraulic system and a brake caliper. The invention further relates to a wind turbine having a rotor brake according to the invention. Background Art

[0002] Known wind turbines are usually equipped with a rotor brake. During maintenance of the wind turbine, the brake is applied to prevent the rotor of the wind turbine from unnecessary and therefore potentially dangerous movements. To this end, the rotor brake usually has at least one brake caliper, which usually acts on a brake disk arranged on the generator shaft to lock the generator shaft.

[0003] The use of hydraulic systems has proven that hydraulic systems are suitable for rotor brakes. These hydraulic systems known in the prior art have a hydraulic device and the pressure relief valves, pressure switches and switching valves required for this purpose to provide pressure to the rotor brake. The operating pressure for the rotor brake can be provided by operating the hydraulic device in accumulator charging mode. Once the maintenance process is completed, the hydraulic device is shut down, thereby releasing the rotor brake. Such a hydraulic system is known from DE 10 2007 002 137 A1, for example. DE 10 2017 102 375 B3 discloses a hydraulic system with a manually operable emergency pump.

[0004] These well-known solutions operate reliably and can also be easily operated by maintenance technicians. However, the known solutions have the disadvantage that a large number of relatively expensive components are required. We would like to provide a solution that is significantly more cost-effective, especially considering the shorter time required to use the hydraulic device. Summary of the invention

[0005] It is therefore an object of the present invention to provide a more cost-effective hydraulic system for a rotor brake of a wind turbine.

[0006] The above mentioned problem is solved by a hydraulic system for a rotor brake of a wind turbine according to claim 1. Further preferred embodiments are described in the dependent claims.

[0007] The hydraulic system for a rotor brake of a wind turbine according to the present invention has a manually operable pump device and a connection portion for connecting to the rotor brake. The manually operable pump device is connected to the connection portion. In this way, no expensive hydraulic device is required. Instead, the operating pressure required for the rotor brake is provided by the inexpensive manually operable pump device. According to the present disclosure, the manually operable pump device includes a coupling portion for actuation, wherein the coupling portion is capable of being coupled to an external device. In other words, the coupling portion is configured to be coupled to an external device. Therefore, a maintenance technician can use an external device coupled to the coupling portion to actuate the pump device, so that the necessary operating pressure can be generated.

[0008] A connection in the sense of the invention does not necessarily refer to a single connection. Instead, a connection may also refer to a plurality of connections and further supply lines, such as a connection option for a leakage line or the like.

[0009] A further advantage of the hydraulic system is that it has an oil tank chamber which is connected to the manually operable pump device. The oil tank chamber can be used, for example, to compensate for temperature fluctuations.

[0010] 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. The first shut-off valve can be arranged in the first bypass line. In particular, the first shut-off valve can be a pressure relief valve or a stop valve.

[0011] A shut-off valve configured as a pressure relief valve can be used to provide protection in the event of overpressure. If the shut-off valve is configured as a manually openable shut-off valve, a maintenance technician can directly adjust the pressure applied to the connection, for example to compensate for temperature fluctuations.

[0012] In this context, the hydraulic system preferably 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 shut-off valve can be arranged in the second bypass line. Preferably, the second shut-off valve is a pressure relief valve or preferably a manually openable shut-off valve, and the type of the second shut-off valve is different from the first shut-off valve. In other words, if the first shut-off valve in the preferred embodiment is configured as a pressure relief valve, the second shut-off valve is configured as a shut-off valve.

[0013] Preferably, the hydraulic system is configured as a single cylinder. This threaded cartridge design makes the hydraulic system particularly easy to install and integrate.

[0014] Preferably, the hydraulic system is hydraulically preloaded, preferably by a spring preload integrated in the manually operable pump device or an integrated hydraulic accumulator. In this way, temperature fluctuations and small leaks of the brake caliper can be directly compensated. It is conceivable that the tank chamber is configured as a hydraulic accumulator.

[0015] Preferably, the external device connected to the coupling is a tool or an external motor. In this way, a maintenance technician can use the tool to actuate the pump device and generate the necessary operating pressure. The tool can also be provided, for example, on a cordless screwdriver or the like. It is also conceivable to use an external motor to provide the operating pressure via a manually operable pump device. In this way, the hydraulic system is particularly easy to drive in order to provide the operating pressure required for applying the brakes.

[0016] Preferably, the manually operable pump device comprises a pressure chamber, a housing, a transmission shaft and a piston element, wherein the pressure chamber is at least partially formed by the housing. The piston element is movably arranged in the pressure chamber, and the transmission shaft is rotatably mounted relative to the housing and connected to the piston element, wherein rotation of the transmission shaft drives the piston element to move linearly or axially in the pressure chamber and thus relative to the housing. When the maintenance technician rotates the transmission shaft, the piston element moves linearly in the pressure chamber to generate the necessary operating pressure.

[0017] Preferably, the piston element is guided in the housing in such a way that a rotation of the piston element relative to the housing is prevented. Thus, the transmission shaft can rotate relative to the housing, but cannot move axially or linearly. The rotational movement of the transmission shaft is transmitted to the piston element via a suitable interface, for example via a threaded connection between the transmission shaft and the piston element.

[0018] Alternatively, it may be preferred if the transmission shaft is axially movable relative to the housing and moves with the piston element. Thus, when the transmission shaft rotates, the transmission shaft moves axially relative to the housing, thereby becoming a rising transmission shaft. This has the advantage that no separate bearing is required to support the rotational movement of the transmission shaft, such as a roller bearing or a sliding bearing.

[0019] The fully integrated hydraulic system configured in this way can be set directly on the brake caliper or used as a stand-alone solution.

[0020] 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 transmission shaft and the second piston part is connected to the first piston part via the preload element. Hydraulic preloading of the hydraulic system can be achieved via the preload element, for example to compensate for minor leaks or temperature fluctuations of the brake caliper.

[0021] Preferably, the manually operable pump device has a locking element that can be moved between a release position and a locking position. When the locking element is in the locking position, the transmission shaft is locked and thus fixed so as not to rotate relative to the housing. When the locking element is in the release position, the transmission shaft can rotate relative to the housing. By moving the locking element from the release position to the locking position, a maintenance technician can safely prevent further rotation of the transmission shaft and thus prevent changes in the operating pressure.

[0022] Alternatively, the manually operable pump device may be a gear pump having a transmission shaft, wherein the coupling portion is arranged on the transmission shaft. Preferably, the coupling portion is arranged at an axial end of the transmission shaft of the gear pump.

[0023] Since the gear pump may leak, a manually unlockable non-return valve may be provided between the gear pump and the connection. The manually unlockable non-return valve prevents a backflow from the connection to the gear pump, thereby locking the pressure between the non-return valve and the connection or the brake caliper connected to the connection, thereby holding the brake caliper in the extended position. To retract the brake caliper, the manually unlockable non-return valve may be manually unlocked.

[0024] Preferably, the hydraulic system has a manually operable lever mechanism for unlocking the check valve. For example, the lever mechanism can be configured as a button or a lever.

[0025] It is particularly preferred if a manually operable lever mechanism is connected to the transmission shaft of the gear pump, so that an axial movement of at least a part of the transmission shaft actuates the lever mechanism and unlocks the non-return valve. For example, a maintenance technician can use an external device attached to the coupling to axially move the entire transmission shaft or a part of the transmission shaft, for example by pushing it in. This unlocks the non-return valve, and a rotation of the transmission shaft pressurizes or releases the connection depending on the direction of rotation.

[0026] Preferably, the manually operable pump device is a reversible manually operable pump device. In this way, the operating pressure applied to the connection part can be reduced by reversing the rotation direction of the drive shaft.

[0027] The invention further relates to a rotor brake for a wind turbine, wherein the rotor brake has at least one brake caliper and a hydraulic system according to the invention described above, wherein the brake caliper is hydraulically connected to a connection of the hydraulic system. Furthermore, the invention further relates to a wind turbine having such a rotor brake.

[0028] BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention will be explained in more detail below with reference to the embodiments shown in the accompanying drawings. The accompanying drawings schematically show:

[0030] Figure 1 is a side view of a wind turbine;

[0031] Figure 2 is a hydraulic circuit diagram of a rotor brake having a hydraulic system according to a first embodiment of the present invention;

[0032] Figure 3 is an exemplary structural configuration of a hydraulic system according to the present invention according to a first embodiment;

[0033] Figure 4 is an alternative exemplary structural configuration of the hydraulic system according to the present invention according to the first embodiment;

[0034] Figure 5 is a hydraulic circuit diagram of a rotor brake having a hydraulic system according to a second embodiment of the present invention; and

[0035] Figure 6 According to the second embodiment Figure 5 A hydraulic circuit diagram of an alternative to the hydraulic system of the present invention. DETAILED DESCRIPTION

[0036] Figure 1 A schematic side view of a wind turbine 100 is shown. The wind turbine 100 has a tower 102 and a nacelle 104 attached to the tower 102. A rotor 106 is rotatably mounted on the nacelle 104. The wind turbine 100 also includes a plurality of rotor blades 108 attached to the rotor 106. In addition, the wind turbine also includes a pitch system (not shown) configured to adjust the aerodynamic angle of attack of one or all rotor blades 108 of the wind turbine 100 according to environmental conditions. The pitch system changes the angle of attack of the rotor blades 108 according to the current wind speed, so as to operate the wind turbine 100 with the best possible efficiency and thus with a substantially constant rated power. To this end, the angular position of the rotor blades 108 relative to the rotor 106 can be adjusted by the pitch system to generate the best possible lift. The pitch system is also configured to prevent the wind turbine 100 from being damaged in strong winds by turning the rotor blades 108 into the wind. The rotor blades 108 are also in the corresponding position when maintenance is required. This interrupts the lift of rotor blades 108 and rotor 106 stops rotating.

[0037] In order to prevent the rotor 106 from being started again during maintenance of the wind turbine 100 , which may be dangerous in certain circumstances, the rotor 106 may be locked by means of the rotor brake 1 .

[0038] Figure 2 The hydraulic circuit diagram of the rotor brake 1 according to the present invention is shown. The rotor brake 1 includes a hydraulic system 10 according to the first embodiment, a brake caliper 2 and a brake element (not shown), such as a disc brake. The hydraulic system 10 is used to generate the operating pressure required to lock the rotor 106, and the operating pressure is applied to the brake caliper 2, thereby applying the brake.

[0039] The hydraulic system 10 comprises 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, a maintenance technician can generate the required operating pressure of the rotor brake 1 via the manually operable pump device 12. For this purpose, the brake caliper 2 is connected to the connection 13 of the hydraulic system 100 in a known manner via a line 3.

[0040] The hydraulic system 10 also has a first bypass line 14, wherein a first shut-off valve 15 is configured as a pressure relief valve. The hydraulic system 10 also has a second bypass line 16, wherein a second shut-off valve 17 is configured as a stop valve. The first bypass line 14 and the second bypass line 16 each bypass the manually operable pump device 12 and connect the connection 13 directly to the tank chamber 30. The pressure relief valve 15 protects the hydraulic system 10 in the event of an overpressure. The stop valve 17 is configured as a manually openable stop valve so that a maintenance technician can reduce the pressure applied to the brake caliper 2 when necessary, for example in the event of temperature fluctuations.

[0041] Figure 3 An exemplary structural configuration of a hydraulic system 10 according to the invention according to a first embodiment is shown. The manually operable pump device 12 has a housing 18, a transmission shaft 19 and a piston element 20. The piston element 20 comprises a first piston part 21, a second piston part 22 and a preload element 23. The pressure chamber 11 is at least partially formed by the housing 18. The piston element 20 is arranged to move linearly in the pressure chamber 11 or the housing 18 to change the volume of the pressure chamber 11 and thus provide an operating pressure at the connection 13. The preload element 23 is supported on the first piston part 21 and the second piston part 22, so that the hydraulic system 10 is hydraulically preloaded, for example to compensate for small leaks in the brake caliper 2.

[0042] As shown in the figure, the connection part 13 is formed on the axial end surface of the housing 18, and the pipeline 3 is fixed to the connection part 13 by screw connection or the like. Of course, the pipeline 3 can also be fixed to the connection part 13 by other means.

[0043] The transmission shaft 19 is rotatably supported on the housing 18 by at least one bearing 24, wherein the transmission shaft 19 cannot move axially relative to the housing 18. To this end, the housing 18 may have, for example, an intermediate plate 25, on which the transmission shaft 19 is axially supported by a circumferential ring 31 (the circumferential ring may be centered by the bearing 24), thereby being fixed to prevent axial movement or axial drift. Of course, the transmission shaft 19 may also be fixed to prevent its axial movement by other means.

[0044] The transmission shaft 19 is connected to the piston element 20, so that the rotational movement of the transmission shaft 19 is converted into a linear movement of the piston element 20. In the embodiment example shown, the transmission shaft 19 is connected to the first piston part 21 via a threaded connection 26. The first piston part 21 is guided in the housing 18 in such a way that the first piston part 21 is prevented from rotating relative to the housing 18. For example, this can be achieved by a groove guide device (not shown). Of course, other anti-rotation devices can also be used.

[0045] By rotating the transmission shaft 19, the first piston part 21 is moved relative to the transmission shaft 19 and thus relative to the housing 18 due to the threaded connection 26. The linear movement of the first piston part 21 is transmitted to the second piston part 22 via the preload element 23, and the volume of the pressure chamber 11 is thus increased or decreased depending on the direction of rotation of the transmission shaft 19. The manually operable pump device is thus a reversible manually operable pump device. By reversing the direction of rotation of the transmission shaft 19, the operating pressure of the connection 13 can be reduced.

[0046] Alternatively, the transmission shaft 19 can also be configured to rise. The transmission shaft 19 is then rigidly connected to the piston element 20 or the first piston part 21 and moves axially 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 need to be fixed to prevent rotation.

[0047] A coupling 27 is provided at an axial end of the drive shaft 19, opposite the threaded connection 26. An external device, such as a suitable tool, can engage with the coupling 27 to rotate the drive shaft 19. For example, the coupling 27 can be configured as a hexagon, so that a maintenance technician can use a cordless screwdriver with a corresponding nut to actuate the manually operable pump device 12. However, other types of actuation by other external devices are of course also conceivable, such as actuation by a couplable foot lever or hand lever or by an external motor.

[0048] Furthermore, the manually operable pump device 12 has a locking element 28. The locking element 28 can be moved between a release position and a locking position. When the locking element 28 is in the release position, the drive shaft 19 can be rotated and the manually operable pump device 12 can be actuated. In the locking position, the locking element 28 blocks the rotational 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 can be moved in the intermediate plate 25 and thus blocks the rotation of the drive shaft in the locking position. Of course, other configurations are also conceivable, for example by means of a switching disk, which can be switched by a switch lever, in each case the switch lever blocks a rotation in one direction depending on the position of the switch lever.

[0049] like Figure 3 As shown, the pressure chamber 11 is also connected to the brake caliper 2 via a leakage line 29. In the present exemplary embodiment, the tank chamber 30 is configured as an additional tank 30. The leakage line 29 and the additional tank 30 are connected to the pressure chamber 11 via a check valve 32. This ensures that sufficient hydraulic oil is maintained in the hydraulic system 10 to generate the operating pressure required to actuate the brake caliper 2 or to provide the required amount. The volume of the additional tank 30 and the leakage line 29 preferably corresponds at least to the maximum volume of the pressure chamber 11.

[0050] Figure 4 An alternative exemplary structural configuration of the hydraulic system 10 of the present invention according to the first embodiment is shown. In this embodiment, the oil tank chamber 30 is at least partially formed in the housing 18. As shown, the pressure chamber 11 is defined by the second piston member 22, so that the oil tank chamber 30 is also formed by the housing 18 and the second piston member 22 and is separated from the pressure chamber 11 by the second piston member 22. The second piston member 22 includes a pressure relief valve 15 and a check valve 32.

[0051] The first piston member 21 is provided with a through hole 33, which is communicated with an additional connecting portion 34 on the housing. If necessary, an additional oil tank (not shown) can be provided on the additional connecting portion 34 to provide a sufficient volume of the oil tank chamber 30.

[0052] The operating pressure is generated at the connection 13 by moving the piston element 20 via the drive shaft 19. Any excess pressure can be released directly via the pressure relief valve 15. The hydraulic oil can be sucked in via the non-return valve 32.

[0053] Figure 4 The exemplary embodiment shown may be configured as a monocoque for quick and easy installation.

[0054] Figure 5 1 shows a hydraulic circuit diagram of a hydraulic system 50 according to the invention according to a second embodiment. The hydraulic system 50 has a pressure chamber 11, a tank chamber 30, a manually operable pump device 12 and a connection 13. During maintenance of the wind turbine 100, a maintenance technician can generate the required operating pressure of the rotor brake 1 by means of the manually operable pump device 12. For this purpose, Figure 2 As shown, the brake caliper 2 is connected to a connection 13 of the hydraulic system 100 via a line 3 .

[0055] Furthermore, the hydraulic system 10 has a first bypass line 14, wherein a first shut-off valve 15 is 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 device 12. The pressure relief valve 15 protects the hydraulic system 10 from excessive pressure.

[0056] In the present embodiment, the manually operable pump device 12 is configured as a reversible gear pump having a drive shaft 51. A coupling portion 27 is provided at an axial end of the drive shaft 51 of the gear pump 12 so that a maintenance technician can connect a suitable external device, such as a cordless screwdriver, to actuate the gear pump 12 by rotating the drive shaft 51, as described above in the first embodiment.

[0057] A manually unlockable check valve 52 is provided between the gear pump 12 and the connection 13. The check valve 52 opens in the direction of flow to the connection 13 and prevents the pressure applied to the brake caliper 2 from being gradually reduced by the leaking gear pump 12. To retract the brake caliper 2, the manually unlockable check valve 52 is unlocked by a maintenance technician.

[0058] For this purpose, the hydraulic system 50 has a manually operable lever mechanism 53. Figure 5 In the embodiment example shown, the lever mechanism 53 takes the form of a button or lever, which a maintenance technician must manually operate to unlock the non-return valve 52. This is also preferred from a safety point of view, since it prevents the brake caliper 2 from being accidentally retracted, for example, if a cordless screwdriver used as an external device is mistakenly set to the wrong direction of rotation.

[0059] Figure 6 An alternative embodiment of a lever mechanism 53 is shown. The lever mechanism 53 is connected to the transmission shaft 51 of the gear pump 12 and is actuated by an axial movement of the transmission shaft 51. A maintenance technician can actuate the transmission shaft 51, for example, by applying a corresponding force to an external device connected to the coupling 27. Of course, it is also conceivable that the transmission shaft 51 comprises an axially movable sleeve or the like, which is connected to the lever mechanism 53 and can be axially moved relative to the base of the transmission shaft 51.

[0060] Reference Figure 5 and Figure 6 The hydraulic system 50 can be used in conjunction with a rotor brake 1 for a wind turbine 100 in the same manner as described above. Figure 2 The hydraulic systems 10 shown are identical.

[0061] Finally, it should be pointed out that the numbers used herein (such as “first” or “second”) do not define a specific order but are only used to distinguish different elements.

[0062] Reference numerals list

[0063] 1 Rotor brake

[0064] 2 Brake calipers

[0065] 3 Pipeline

[0066] 10. Hydraulic system

[0067] 11. Pressure chamber

[0068] 12 Manually operable pump unit / gear pump

[0069] 13. Connection

[0070] 14 First bypass line

[0071] 15First shut-off valve / pressure relief valve

[0072] 16 Second bypass line

[0073] 17 Second shut-off valve / stop valve

[0074] 18 Housing

[0075] 19 Drive shaft

[0076] 20 Piston element

[0077] 21 First piston component

[0078] 22 Second piston component

[0079] 23 Preload components

[0080] 24 Bearings

[0081] 25 Middle plate

[0082] 26 Threaded connection

[0083] 27 coupling portion

[0084] 28 Locking element

[0085] 29 Leaking pipeline

[0086] 30 fuel tank cavity / additional fuel tank

[0087] 31 rings

[0088] 32 Check valve

[0089] 33 Through Holes

[0090] 34 Additional connection

[0091] 50 Hydraulic system

[0092] 51 Drive shaft

[0093] 52 Manually unlockable check valve

[0094] 53 Lever mechanism

[0095] 100 wind turbines

[0096] 102 Tower

[0097] 104 Cabin

[0098] 106 rotors

[0099] 108 rotor blades

Claims

1. A hydraulic system (10, 50) for a rotor brake (1) of a wind turbine (100), wherein: The hydraulic system (10, 50) has a manually operable pump device (12) and a connection (13) for connection to the rotor brake (1), wherein the manually operable pump device (12) is connected to a pressure chamber (11) and the connection (13), It is characterized in that The manually operable pump device (12) comprises a coupling (27) for actuation, which coupling (27) can be connected to an external device.

2. A hydraulic system (10, 50) according to any one of the preceding claims, characterized in that The hydraulic system (10, 50) is configured in a monocylindrical shape.

3. The hydraulic system (10, 50) according to claim 1 or 2, characterized in that: The hydraulic system (10, 50) further comprises a tank chamber (30) connected to the manually operable pump device (12).

4. The hydraulic system (10, 50) according to claim 3, characterized in that The hydraulic system (10, 50) comprises a first bypass line (14) and a first shut-off valve (15), wherein the first bypass line (14) bypasses the manually operable pump device (12) and connects the connection portion (13) to the tank chamber (30), and the first shut-off valve (15) is arranged in the first bypass line (14).

5. The hydraulic system (10, 50) according to claim 4, characterized in that The first shut-off valve (15) is a pressure relief valve or a stop valve.

6. The hydraulic system (10) according to any one of the preceding claims 3 to 5, characterized in that The hydraulic system (10) comprises a second bypass line (16) and a second shut-off valve (17), wherein the second bypass line (16) bypasses the manually operable pump device (12) and connects the connection portion (13) to the tank chamber (30), and the second shut-off valve (17) is arranged in the second bypass line (16).

7. The hydraulic system (10) according to claim 6, characterized in that The second shut-off valve (17) is of a different type than the first shut-off valve (15), wherein the second shut-off valve (17) is a pressure relief valve or a stop valve.

8. A hydraulic system (10) according to any one of the preceding claims, characterised in that The hydraulic system (10) is hydraulically preloaded, preferably by a spring preload integrated in the manually operable pump device (12) or in an integrated hydraulic accumulator.

9. A hydraulic system (10) according to any one of the preceding claims, characterised in that The external device that can be coupled to the coupling portion (27) is a tool or an external motor.

10. The hydraulic system (10) according to any one of the preceding claims, characterized in that The manually operable pump device (12) comprises a pressure chamber (11), a housing (18), a transmission shaft (19) and a piston element (20), wherein the pressure chamber (11) is formed in the housing (18), the piston element (20) is movably arranged in the pressure chamber (11), the transmission shaft (19) is rotatably mounted relative to the housing (18) and connected to the piston element (20), and the rotation of the transmission shaft (19) drives the piston element (20) to move linearly in the pressure chamber (11).

11. The hydraulic system (10) according to claim 10, characterized in that The piston element (20) is guided in the housing (18) in such a way that a rotation of the piston element (20) relative to the housing (18) is prevented, or The transmission shaft (19) is axially movable relative to the housing (18) and moves together with the piston element (20).

12. The hydraulic system (10) according to claim 10 or 11, characterized in that The piston element (20) comprises a first piston component (21), a second piston component (22) and a preload component (23), wherein the first piston component (21) is connected to the transmission shaft (19), and the second piston component (22) is connected to the first piston component (21) via the preload component (23).

13. The hydraulic system (10) according to any one of claims 10 to 12, characterized in that The manually operable pump device (12) has a locking element (28) movable between a release position and a locking position, wherein the transmission shaft (19) is locked and fixed so as not to rotate relative to the housing (18) when the locking element (28) is in the locking position, and wherein the transmission shaft (19) is rotatable relative to the housing (18) when the locking element is in the release position.

14. The hydraulic system (50) according to any one of claims 1 to 5, characterized in that: The manually operable pump device (12) is a gear pump having a transmission shaft (51), on which the coupling (27) is arranged.

15. The hydraulic system (50) according to claim 14, characterized in that A manually unlockable check valve (52) is arranged between the gear pump (12) and the connection portion (13).

16. The hydraulic system (50) according to claim 15, characterized in that The hydraulic system (50) comprises a manually operable lever mechanism (53) for unlocking the check valve (52).

17. The hydraulic system (50) according to claim 16, characterized in that The manually operable lever mechanism (53) is connected to the transmission shaft (51) of the gear pump, wherein an axial movement of at least a portion of the transmission shaft (51) is capable of actuating the lever mechanism (53) and unlocking the check valve (52).

18. A hydraulic system (10, 50) according to any one of the preceding claims, characterised in that The manually operable pump device (12) is a reversible manually operable pump device (12).

19. A rotor brake (1) for a wind turbine (100), wherein: The rotor brake (1) has at least one brake caliper (2) and a hydraulic system (10, 50) according to any of the preceding claims, wherein the brake caliper (2) is hydraulically connected to the connection (13) of the hydraulic system (10).

20. A wind turbine (100) having a rotor brake (1) according to claim 19.

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