DE20021026U1 - Grease lubrication system, grease container and wind turbine - Google Patents

Description

GRÜNECKER y STtfckl^AJlf ^iSQHWANHAUSSER

GKS & S MAXIMILIANSTRASSE 58 D-80538 MUNICH GERMANY

Applicant:

VOGEL FLUIDTEC GMBH

2. INDUSTRIESTRASSE 68757 HOCKENHEIM

YOUR REF.

LAWYERS PATENT ATTORNEYS PATENT ATTORNEYS LAWYERS EUROPEAN PATENT ATTORNEYS EUROPEAN PATENT ATTORNEYS MUNICH MUNICH COLOGNE DR. HELMUT EICHMANN DR. HERMANN KINKELDEY OR. MARTIN DROPMANN GERHARD BARTH PETER H. JAKOB DR. ULRICH BLUMENRÖDER, LLM. WOLFHARD MEISTER CHEMNIT2 CHRISTA NIKLAS-FALTER HANS HILGERS MANFRED SCHNEIDER DR. MAXIMILIAN KINKELDEY, LLM. DR. HENNING MEYER-PLATH SONJA SCHAEFFLER ANNELIE EHNOLD BERLIN OR.KARSTEN BRANDT THOMAS SCHUSTER DIETER JANDER MICHAEL J. FRANKE, LLM. DR. KLARA GOLDBACH UTE STEPHANI MARTIN AUFENANGER DR. BERND ALLEKOTTE, LL.M. GOTTFRIED KUTZSCH DR. HEIKE VOGELSANG-WENKE OF COUNSEL REINHARD KNAUER PATENT ATTORNEYS DIETMAR KUHL DR. FRANZ-JOSEF ZIMMER AUGUST GRÜNEECKER BETTINA K. REICHELT DR. GUNTER BEZOLD DR. ANTON K. PFAU DR. WALTER LANGHOFF DR. UDO WEIGELT RAINER BERTRAM JENS KOCH, M.S. (U ofPA) M.S. BERND ROTHAEMEL DR. WILFRIED STOCKMAIR DR. DANIELA KINKELDEY (-1996) DR. EN/OUR REF. DATE

G 4449-25/Sü

12.12.00

Grease lubrication system, grease tank and wind turbine

GRÜNECKER KINKELDEY STOCKMAIR & SCHWANHAUSiE ¹ p . '.'*'

MAXIMIUANSTR. 58 · · ·**

D-80538 MUNICH i..*J...

GERMANY

+49 89 21 23 50

22,L>?§7 _# ··, tt3R4) ^*9 q? 21J86 J2 93!

e-mail: postmaster@grunecker.de

DEUTSCHE BANK MUNICH No. 17 51734 BLZ 700 700 SWIFT: DEUT DE MM

Grease lubrication system, grease tank and wind turbine

The invention relates to a grease lubrication system according to claim 1, a grease container for a grease lubrication system according to the preamble of claim 18 and a wind turbine according to the preamble of claim 19.

Grease lubrication systems or centralized grease lubrication systems have been known for decades for various, mostly stationary applications. The pump is assigned a grease container containing a supply of grease, from which lubrication is drawn. Since the pump with the grease container is usually easily accessible, the grease container, which forms a structural unit with the pump, is refilled as needed from a filling system transported there, for example via a filling connection on the pump housing.

Wind turbines generate electricity from wind power. The rotor is located up to 100 m or higher above the ground on or in the machine house. Bearings are currently either manually lubricated or supplied from so-called permanent bushings, i.e. permanently attached gas-pressure lubricant dispensers. These are not only expensive, but also take up a relatively large amount of installation space. The operational reliability that can be achieved with them no longer meets modern requirements. Remote monitoring is also hardly possible. The maintenance requirement is high. Maintenance is expensive, e.g. in offshore wind turbines. There are already test wind turbines in Spain in which a basic grease exchange is carried out in the rolling bearings at six-month maintenance intervals.

In the recent past, the need arose to solve lubrication problems in wind turbines in a different way in order to increase operational reliability and achieve the longest possible maintenance intervals. So-called grease progressive central lubrication systems are suitable for this purpose, i.e. grease pumps with one or more downstream progressive distributors that distribute the grease pumped by the grease pump to the lubrication points. Conventional grease lubrication systems, in which the grease container has to be filled at the pump, are not suitable for wind turbines because

a conventional filling system cannot be brought to the exposed site with reasonable technical or personnel expenditure.

The invention is based on the object of specifying a grease lubrication system in which the filling of the grease container can be accomplished in a different way than previously, or of specifying a grease container for a grease lubrication system that can be conveniently filled regardless of the location of the grease lubrication system, and of equipping a wind turbine with a maintenance-friendly central grease lubrication system in order to increase operational reliability.

The problem is solved with the features of claim 1 or the features of claim 18 or the features of claim 19.

Since the grease container can be easily removed from the pump, it can be refilled at a suitable location without necessarily having to bring the filling system to the location where the lubrication system is used. It is only necessary to ensure that the grease is refilled in such a way that no significant air inclusions occur.

According to claim 18, the grease container is designed as an interchangeable container which can be easily separated from the pump, can be filled separately from the pump, and is also provided with an auxiliary filling device which enables convenient and clean, i.e. complete, filling without air inclusions.

The wind turbine according to claim 19 is characterized by increased operational reliability and a low maintenance frequency due to the safety of the central grease lubrication system, because the grease is used economically and in a targeted manner and remote monitoring is possible, so that refilling actually only has to be carried out when the grease supply is about to run out.

Handling when refilling the grease container is convenient if the pump housing has a receiving opening for the open container end and fastening

means are provided which allow the grease container to be easily loosened and tightened.

In a simple embodiment, the receiving opening is a plug-in seat for the end of the container. The end of the container is releasably secured using suitable fastening means.

In an alternative embodiment, a screw connection or bayonet connection is provided between the grease container and the pump housing.

In a particularly practical embodiment, a stationary pull stop and a movably mounted screw-on ring are permanently arranged on the outside of the grease container, and the screw-on ring works together with a screw abutment of the pump housing in order to make the grease container easy to remove at any time and yet still tightly secured.

The screw abutment for the screw-on ring can be arranged together with the seat for the container end in a ring flange attached to the pump housing.

In order to prevent air from entering the grease and to ensure that the grease follower piston is properly moved even under extreme operating conditions (different working temperatures, non-vertical position of the grease container, low specific consumption, etc.), it is advisable to provide at least two axially separated sliding seals.

In principle, remote monitoring of the grease tank level is advisable. In wind turbines in particular, the grease level can be monitored either in the overhead machine room and/or at the foot of the mast and/or in a remote monitoring center if the grease tank contains an electrical level control device.

An axial contact rod is suitable for this purpose, via which the axial position of the grease follower piston is sensed and reported electrically.

In order to exclude leaks in the passage of the contact rod, several axially spaced sliding seals or an extended sliding seal should be provided there.

An independent inventive idea is to design the grease container as an interchangeable container that can be filled separately from the pump housing. This not only enables the removed grease container to be conveniently filled separately from the pump housing and at a suitable location, but also makes filling considerably easier. The already filled interchangeable container only needs to be transported to the location of the grease lubrication system and exchanged for the empty grease container there. This saves downtime for the grease lubrication system and simplifies maintenance because the location of the lubrication system only needs to be visited once.

The swap container is conveniently fitted with a filling aid that can only be attached for filling, with which the new grease supply can be introduced quickly and without air inclusions. The filling aid can then be removed in order to put on a simple protective cap if necessary. It can also remain on the swap container as a temporary closure until it is exchanged for the empty grease container at the grease lubrication system's location.

It is advantageous to design the auxiliary filling device as a filling pot with an integrated filling connection. For safety reasons, a filling protection device should also be provided on the filling pot. The filling system only needs to generate delivery pressure. This is particularly useful for grease lubrication systems that are located in exposed locations, such as on wind turbines, as it simplifies maintenance.

Convenient handling of the auxiliary filling device on the swap body is possible if the same fastening element is used to fix the auxiliary filling device as is used to fix the swap body on the pump housing

is done, for example, by providing the filling pot with an external thread that matches the internal thread of the screw-on ring on the swap container.

In this embodiment, the screw-on ring should sit easily on the outer wall of the cylindrical grease container and have a sufficiently long skirt that can be screwed either onto the pump housing or onto the auxiliary filling device. The pull stop can be a ring flange on the outer wall of the grease container or can be formed by several projections inserted into the outer wall. Sliding plastic in this area reduces the rotational resistance of the screw-on ring under the tightening force.

In the case of the wind turbine, only one maintenance operation is required to refill the grease supply if the grease container is designed as a swap container which, when emptied, is replaced by a full swap container in one operation.

Embodiments of the subject matter of the invention are explained with reference to the drawing. They show:

Fig. 1 is a schematic sectional view of the rotor area of a wind turbine with several lubrication points,

Fig. 2 is a schematic section of another embodiment of the rotor area of a wind turbine,

Fig. 3 a side view of a pump with a grease tank of a grease lubrication system,

Fig. 4 is a longitudinal section of another embodiment of a grease lubrication system, and

Fig. 5 is a longitudinal section of a grease container designed as an interchangeable container with a removable filling aid and a protective cap,
as used in Fig. 1 to 4.

Fig. 1 shows part of a so-called machine house of a wind turbine W on a mast M. A rotor 5 equipped with adjustable rotor blades 7 on a main axis 4 can at least be rotated relative to the mast M by means of a so-called azimuth drive 1. The rotor 5 drives a generator G, for example a generator G with a disc rotor 2. A main bearing 3 is provided for the disc rotor 2. Another main bearing 6 is provided for the rotor 5. The rotor blades 7, which can be adjusted by means of rotor blade adjusters 13, are mounted in so-called pitch bearings 8. To supply the various bearing points with grease, a central grease lubrication system Z with at least one pump P and a grease container B is arranged on the disc rotor 2 in such a way that the longitudinal axis of the grease container B is approximately parallel to the rotor axis 4. The lubrication system moves with it. The lubrication points are supplied with grease via, for example, a progressive value distributor V and secondary distributor 9. An electrical, shape-monitorable fill level control device F is provided on the grease container B.

In the wind turbine W shown partially schematically in section in Fig. 2, the rotor 5 drives the generator G, which is attached as a separate structural unit, via a gear 10. A servo motor with gear and gear drive is indicated for the azimuth drive 1, with the entire rotor area being mounted on the upper end of the mast M in a bearing area 11. In the wind turbine W in Fig. 2, several central grease lubrication systems Z, Z1, Z2 and Z3 are indicated. The grease lubrication system Z is used, as in Fig. 1, to lubricate various bearing points in the rotor area, with the central grease lubrication system Z with its pump P and the grease container B moving with the rotor. The grease lubrication system Z2 is used to lubricate the azimuth drive and its bearing points 11. The grease lubrication system Z1 is used to lubricate main bearings 12 of the shaft that connects the rotor 5 to the gear 10. The grease lubrication system Z3 is used to supply the lubrication points in the area of the generator G. Progressive distributors to the lubrication points are indicated, and each grease lubrication system Z to Z3 has at least one pump with a grease container.

Fig. 3 illustrates a pump P with its grease container B, as used in Fig. 1 and 2. The pump P is housed in a housing 14 which has a suction

side of the pump P with an open container end 17 of the grease container B. Q indicates a pump element (piston pump element) which is inserted from the outside into the housing 14 and (Fig. 4) interacts with an eccentric 36 driven by an electric motor E, which drives a plunger 37 of the pump element Q back and forth. The pump can be equipped with several pump elements Q.

A filling connection 22 and a filling safety device 21 are provided in the housing 14. A conventional filling system can be connected to the filling connection 22, which generates the delivery pressure for filling the grease container B. The grease container B has a cylindrical container wall 15, an upper end closure 16 and the already mentioned open lower container end 17. The filling level control device F has a detector 14 at the upper end section 16 and a contact rod 23 running axially inside the grease container B with sensors (not shown in detail in Fig. 3) for sensing the axial position of a grease follower piston K, which limits the space filled with grease in the grease container B and can be moved depending on the grease consumption from the upper maximum position shown in dashed lines in Fig. 3 (maximum filling) to the position shown below (minimum filling). For example, an outer flange 18 is welded to the open end 17 of the container, with which the grease container B sits on the housing 14. Detachable fastening means (not shown) are used to removably attach the grease container B to the pump P.

The grease container B can be pulled out after loosening the retaining screws 20 and transported to a filling station in order to be filled separately from the pump and in a suitable location and under convenient conditions.

The detailed structure of Fig. 4 shows another embodiment of a grease container B. The grease container B is detachably attached to the housing 14 of the pump P and can be designed, for example, as the interchangeable container _Bw shown in Fig. 5. This means that the grease container B in Fig. 4 can be removed from the housing 14 for refilling and brought to a filling location separate from the pump and filled there, or that the grease container B in Fig. 4 is removed in an empty state and only replaced by the filled interchangeable container Bw from Fig. 5.

In Fig. 4, the entire interior space below the grease follower piston K is normally filled with grease L down to below the pump element Q. The open end of the container 17 sits in a seat 39 of an annular flange 38 which is fixed to the housing 14 or is formed integrally with it. In the embodiment shown, the annular flange 38 has an external thread with a thread diameter larger than the external diameter of the grease container B. On the outer wall of the grease container B, at a distance above the open end of the container 17, a tension stop 32 (for example an annular flange or projections distributed in the circumferential direction and inserted into the outer wall) is provided, above which an annular collar 33 of a screw-on ring 31 is held slidably on the outer wall. An apron 31 extends from the annular collar 33 down beyond the open end of the container 17. An internal thread is provided inside the apron 35 which matches the external thread of the annular flange 38. Turning aids 34, e.g. for a pick wrench, can be molded into the collar 33 or the apron. The open end 17 of the container is clamped tightly into the seat 39 by means of the screw-on ring 31. After loosening the screw-on ring 31, the grease container B can be pulled out of the seat 39. To reduce the resistance of the screw-on ring 31 to rotation, the pull stop 32 is expediently made of slippery plastic or covered with slippery plastic.

Sensors 26 for the minimum and maximum fill levels are indicated by dashed lines in the contact rod 23. These detect and report the axial position of the grease follower piston K, which has at least two axially separated sliding seals 27 for secure sealing on the inner wall. The contact rod 23 passes through a passage 29 of the grease follower piston K. At least two sliding seals or an extended sliding seal 28 should also be provided in this area. The upper container section 16 is secured with pins 25 in the container wall 15.

The swap body Bw shown in Fig. 5 is provided with an auxiliary filling device T, which is expediently only used for filling and then removed again. Alternatively, it is conceivable to leave the auxiliary device T in the original position until the full swap body _Bw is installed instead of the empty grease container B in Fig. 4.

• · &igr;

shown position as a closure at the open container end 17 and to be removed only before inserting the interchangeable container B _w into the housing 14.

The auxiliary filling device T consists of a filling pot 40 with a seat 39 for the open container end 17. An external thread is provided on the filling pot 40 which matches the internal thread of the screw-on ring 31. The filling pot also has a filling connection 22 and, if necessary, an integrated filling safety device 21.

Alternatively, Fig. 5 shows a closure cap 41 which is placed on the open end of the container 17 after the filling of the swap container Bw and removal of the excess grease after the auxiliary filling device T has been removed. If necessary, the closure cap 41 can even be secured using the screw-on ring 31. The full swap container B _w is closed using the auxiliary filling device or brought to the location of the pump with the closure cap 41. The emptied grease container B is then removed, the auxiliary filling device T or the protective cap 41 is removed, and the full swap container B _w is inserted into the housing 14. The separation point between the swap container and the pump should be geometrically designed in such a way that when the filled swap container is placed on top, there is some excess grease which must be wiped off. This is a simple and reliable way of preventing harmful air from entering.

As an alternative not shown, the connection between the grease container or exchangeable container can be a screw connection between the open container end 17 and the seat 39 or the ring flange 38 of the housing 14, or a bayonet lock connection provided at this point with matching bayonet lock parts arranged on the grease container and on the housing.

The removable grease container according to Fig. 3 or 4 or the exchange container B _w according to Fig. 5 are particularly suitable for use in grease lubrication systems on wind turbines with lubrication points that are exposed and high above the ground, because a single maintenance operation is sufficient for refilling and the full exchange container Bw or the empty grease container can be easily transported by one person. The integrated electrical fill level control device F enables remote monitoring.

Checking the grease supply so that refilling can only be carried out at the right time.

The grease container B or exchangeable container B _w has, for example, for an intermittently operated pump P with a delivery capacity of, for example, approx. 2.5 crrvVmin, a diameter of approximately 150 to 250 mm and a length of approximately 250 to 450 mm, and is suitably made of light metal or at least partly of plastic.

Claims (20)

1. Grease lubrication system, in particular for a wind turbine, with a pump (P) and at least one grease container (B) connected to the suction side of the pump (P) and containing at least one grease follower piston (K), characterized in that the grease container (B) is detachably connected to the pump (P) with its open container end (17). 2. Grease lubrication system according to claim 1, characterized in that a pump housing (14) has a receptacle (19) for the container end (17), and that fastening means for securing the container end (17) of the grease container are provided on the pump housing (14) and/or the grease container (B). 3. Grease lubrication system according to claim 2, characterized in that the receptacle (19) is a plug-in seat for the container end (17). 4. Grease lubrication system according to claim 2, characterized in that the receiving opening (39) is a seat with an internal thread or a bayonet closure part, an external thread or a bayonet closure part is provided on the container end (17), and that the threaded or bayonet closure parts form the fastening element for securing the grease container. 5. Grease lubrication system according to claim 2, characterized in that a stationary pull stop (32) and a movably mounted screw-on ring (31) are arranged on the outside of the grease container (B), and that the pump housing (14) in the receptacle (19) has a seat (39) for the container end (17) and a screw abutment (38) for the screw-on ring (31) of the grease container. 6. Grease lubrication system according to claim 5, characterized in that the screw abutment (38) and the seat (39) are arranged together in an annular flange attached to the pump housing (14), preferably separably. 7. Grease lubrication system according to claim 1, characterized in that the grease follower piston (K) has several axially separated sliding seals (27) for the inner wall of the grease container (B). 8. Grease lubrication system according to claim 1, characterized in that the grease container (B) has an electrical level control device (F) which senses the axial position of the grease follower piston (K). 9. Grease lubrication system according to claim 8, characterized in that an axial contact rod (23) extending from the container end (16) facing away from the open container end (17) is positioned in the interior of the container and passes through a passage (28) of the grease follower piston (K). 10. Grease lubrication system according to claim 9, characterized in that the grease follower piston (K), preferably in the passage (28), has several axially separated sliding seals or an extended sealing area (29) for the contact rod (23). 11. Grease lubrication system according to claim 1, characterized in that the grease container (B) is designed as an interchangeable container (B _W ) which can be filled separately from the pump housing (14). 12. Grease lubrication system according to claim 11, characterized in that the interchangeable container (B _W ) has an auxiliary filling device (T) which can be attached for filling. 13. Grease lubrication system according to claim 12, characterized in that the auxiliary filling device (T) has a filling pot (40) fitting onto the open container end (17) with a filling connection (22) and, preferably, a filling safety device (21). 14. Grease lubrication system according to claim 13, characterized in that the filling pot (40) has a seat (39) for the open container end (17) and can be fixed to the interchangeable container with the fastening element (31) provided for fixing the interchangeable container to the pump housing (14). 15. Grease lubrication system according to at least one of claims 5 and 14, characterized in that the filling pot (40) has a thread matching the screw-on ring (31), preferably an external thread for the internal thread of the screw-on ring (31). 16. Grease lubrication system according to claim 5, characterized in that the screw-on ring (31) has an annular collar (33) arranged in a sliding fit on the outer wall of the cylindrically designed grease container (B) and a cylinder apron (35) extending from the annular collar at a radial distance from the outer wall, which contains an internal thread, and that the tension stop (32) is formed by an annular flange of the outer wall or by projections inserted into the outer wall and distributed in the circumferential direction. 17. Grease lubrication system according to claim 16, characterized in that the annular flange or the projections consist of slippery plastic or are at least coated with slippery plastic facing the annular collar (33). 18. Grease container for the pump of a grease lubrication system, characterized in that the grease container (B) is designed as an interchangeable container (B _W ) and with an open container end (17), has at least one fastening element (31) for releasably securing the container end to the housing (14) of the pump (P), and that an auxiliary filling device (T) is removably attached to the container end (17) by means of the fastening element (31). 19. Wind power plant (W) with a rotor (5) having adjustable rotor blades (7), which is mounted in a machine house arranged above the ground on a mast (M), and with a grease lubrication device for at least bearing points in the rotor area, characterized in that the lubrication device is a central grease lubrication system (Z) with a pump (P) and a grease container (B), and that the pump with the grease container is arranged on the rotor (5) or a component (2) that can rotate with the rotor, with the grease container axis at least approximately parallel to the rotor axis. 20. Wind power plant according to claim 19, characterized in that the grease container is designed as an exchangeable container (B _W ) or at least as an interchangeable container that can be removed from the pump for refilling.