Transport of lubricant into interior of hollow shaft

Abstract

The invention relates to an assembly having a mechanism (101) fixed relative to a housing, a hollow shaft (103) rotatably mounted in the mechanism (101) fixed relative to the housing, and a lubrication point (107, 203) located at least partially in the interior of the hollow shaft (103). The means (101) fixed relative to the housing has a ring (113) which encloses a cavity with the outer circumferential side of the hollow shaft (103); wherein the ring (113) has one or more bores (113), each of which opens into the cavity; and wherein the hollow shaft (103) has one or more bores (117) which each lead into the interior of the hollow shaft (103) and into the cavity.

Description

Technical Field

[0001] The invention relates to an assembly according to the preamble of claim 1 . Background Art

[0002] In this regard, EP 1 488 139 B1 shows a planetary stage of a transmission with a rotating planet carrier and a static ring gear. The output of the planetary stage is realized by means of a sun gear. The planetary gears and the planetary gear bearings are mounted on a planetary shaft that rotates with the planet carrier. The static pump supplies oil through a static oil line and oil regulating elements (i.e., coolers, filters, etc.). For example, a circular ring made of polyamide has a U-shaped profile and is mounted on the back side of the planet carrier. The ring matches the machined annular groove in the static housing. Since the ring is fixed relative to the rotating planet carrier, the ring also rotates relative to the static housing. The combination of the U-shaped ring and the annular groove in the housing forms a channel through which oil can pass through the hole in the planet carrier locking plate into the cavity on the back side of the planet shaft. From here, the oil moves through the hole in the planet shaft toward the planetary bearing. Since the U-shaped ring is not perfectly matched with the milling groove in the housing, there is a certain amount of oil leakage and pressure drop. Summary of the invention

[0003] The invention is based on the object of transporting oil between a device fixed relative to the housing and a lubrication point located in the interior of the hollow shaft. This object is achieved by an assembly according to claim 1. Preferred developments are contained in the dependent claims and are derived from the following description.

[0004] The assembly comprises a mechanism fixed relative to the housing, a hollow shaft and a lubrication point. The mechanism fixed relative to the housing is a mechanism that is fixedly arranged in the housing, that is, it is impossible for relative movement to occur. In particular, the housing itself is a mechanism fixed relative to the housing.

[0005] The hollow shaft is rotatably supported in a mechanism fixed relative to the housing. Thus, the hollow shaft can rotate relative to the mechanism fixed relative to the housing. The support is achieved by means of one or more bearings that support the hollow shaft in the mechanism fixed relative to the housing. In particular, the outer rings of the bearings can be fixed to the mechanism fixed relative to the housing, while the inner rings are fixed to the hollow shaft.

[0006] The characteristic of a hollow shaft is that its interior is hollow, that is, the hollow shaft surrounds a cavity. This cavity is called the interior of the hollow shaft.

[0007] In particular, the hollow shaft can be configured as an output shaft of a transmission and / or connected or connectable to a rotor of a generator in a rotationally fixed manner. Preferably, the hollow shaft is rotationally symmetrical about its axis of rotation. Therefore, the interior of the hollow shaft is also rotationally symmetrical about the axis of rotation.

[0008] Preferably, the interior of the hollow shaft opens into the two end sides of the hollow shaft. This means that: the two end sides each have an opening, and the interior is accessible from the outside through the opening.

[0009] Lubricated parts refer to mechanisms that require lubricants. In order to avoid wear, lubricants must be supplied to these mechanisms.

[0010] The assembly according to the invention is preferably part of a transmission. This means that the mechanism fixed relative to the housing, the hollow shaft and the lubrication points are also part of the transmission. Preferably, the transmission is a wind turbine transmission.

[0011] According to the invention, the means fixed relative to the housing has a ring. The ring can be connected to the means fixed relative to the housing in one piece or in multiple pieces.

[0012] A ring is a body with a torus shape. It is a surface of revolution with a continuous recess through which the axis of rotation extends.

[0013] The ring surrounds the hollow shaft so that the hollow shaft extends through the recess of the ring, and a part of the hollow shaft is located in the recess. The ring and the outer peripheral side of the hollow shaft together enclose a cavity. Preferably, the cavity is rotationally symmetrical with respect to the rotation axis of the hollow shaft and the above-mentioned rotation axis of the ring.

[0014] The ring has one or more bores, which respectively open into the cavity. A bore is generally a through hole here. A through hole is a hole with exactly two openings. In particular, it can be a cylindrical hole, for example, produced by drilling through.

[0015] The hollow shaft also has one or more bores, which respectively lead into the interior of the hollow shaft and into the cavity. Therefore, the bores of the hollow shaft connect the interior of the hollow shaft and the cavity to each other in an oil-conducting manner.

[0016] The bores of the ring and the hollow shaft serve as lubricant lines. Since they open into the cavity, the cavity forms a lubricant-conducting connection between the ring and the hollow shaft or between its bores. Lubricant can be introduced into the cavity through the bores of the ring. The lubricant passes from the cavity into the interior of the hollow shaft through the bores of the hollow shaft. In this way, the lubrication points located in the interior of the hollow shaft are supplied with oil.

[0017] The advantage of the invention is that it can be realized without major structural changes to conventional components using a mechanism fixed to the housing, a hollow shaft rotatably mounted in the mechanism fixed to the housing, and a lubrication point located in the interior of the hollow shaft. Only a bore and a ring are required to supply oil to the lubrication point. Both the bore and the ring can be produced relatively simply and inexpensively.

[0018] Preferably, the component is further developed to have a shaft and a spline. A spline is a multiple driving connection consisting of two toothed parts. The toothed parts mesh with each other so that they are connected in a relatively rotationally fixed manner. The center axes or rotation axes of the toothed parts coincide.

[0019] The shaft and the hollow shaft are connected to each other in a rotationally-resistant manner via a spline. Specifically, one tooth portion of the spline is connected to the shaft in a rotationally-resistant manner. Another tooth portion of the spline is connected to the hollow shaft in a rotationally-resistant manner. In particular, the shaft and / or the hollow shaft can form the respective tooth portions of the spline in one piece.

[0020] According to a further development, the spline forms the above-mentioned lubrication point. This further development makes it possible to supply the spline with lubricant even if the spline is located at least partially in the interior of the hollow shaft and is therefore difficult to reach.

[0021] The assembly can also be modified to have a through-tube and at least one bearing. A through-tube, also known as a pitch tube, is a tube used to pass through supply lines, such as cables and / or lubricant lines.

[0022] The through-tube is supported in the hollow shaft by means of at least one bearing. As a result, the hollow shaft can be twisted relative to the through-tube. In particular, the through-tube can be arranged fixedly relative to the housing, so that no relative movement can occur between the through-tube and the housing.

[0023] According to a further development, the bearing forms the lubrication point. This further development makes it possible to supply the bearing with oil even if the bearing is at least partially located in the interior of the hollow shaft and is therefore difficult to reach.

[0024] In a preferred improvement, the ring does not contact the outer peripheral side of the hollow shaft. Preferably, one or more gaps extend between the ring and the outer peripheral side of the hollow shaft. The gap can be implemented flat or improved into a labyrinth seal.

[0025] Due to this improvement, oil leakage may occur between the ring and the outer peripheral side of the hollow shaft, and the amount of oil leakage depends on the design of the gap. In order to avoid wear, oil leakage is acceptable.

[0026] Preferably, the assembly is improved to have at least two bearing assemblies. With the bearing assemblies, the hollow shaft is rotatably supported in a mechanism fixed relative to the housing. According to the improved solution, the cavity is arranged axially between the bearing assemblies. This has the advantage that the bearing assemblies are lubricated by the above-mentioned oil leakage.

[0027] Preferably, the hollow shaft is modified to have at least one fluid-dynamic mechanism. The mechanism is a movable mechanism that is designed to build up a fluid-dynamic pressure. The fluid-dynamic pressure is generated by the fluid-dynamic effect generated when the mechanism moves. Here, the mechanism moves due to the rotation of the hollow shaft. Preferably, the mechanism is correspondingly connected to the hollow shaft in a rotationally fixed manner. In particular, the hollow shaft can form the mechanism in one piece.

[0028] According to the improvement, the mechanism generates fluid dynamic pressure when the hollow shaft rotates, and this fluid dynamic pressure acts on at least one through-port of the bore of the hollow shaft. Therefore, the fluid dynamic pressure promotes oil to be transported from the cavity to the inside of the hollow shaft through the bore of the hollow shaft.

[0029] Preferably, the mechanism is configured as a deepening or pocket. Preferably, it is located before at least one through-opening in the rotational direction of the shaft. Preferably, there is also a protrusion or shoulder behind at least one through-opening in the rotational direction of the shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The preferred improvement of the present invention is shown in the drawings. Here, the same reference numerals represent the same or functionally the same features. In the drawings:

[0031] Figure 1 An assembly for supplying oil to the splines is shown;

[0032] Figure 2 An assembly for supplying oil to the bearing of the through-tube is shown;

[0033] Figure 3

[0034] Figure 4 Shows a detailed view with a labyrinth seal; and

[0035] Figure 5 The pocket that acts as a fluid dynamic is shown. DETAILED DESCRIPTION

[0036] Figure 1 The assembly shown includes parts of a transmission housing 101 , a hollow shaft 103 and a sun shaft 105 .

[0037] The hollow shaft 103 and the sun shaft 105 each constitute a part of the spline 107. The hollow shaft 103 and the sun shaft 105 are connected to each other in a rotationally fixed manner by means of the spline 107. The spline 107 is located inside the hollow shaft 103. Accordingly, the hollow shaft 103 constitutes an internal tooth portion belonging to the spline 107, and the sun shaft 105 constitutes an external tooth portion belonging to the spline 107. The internal tooth portion and the external tooth portion mesh with each other and are thus connected to each other in a rotationally fixed manner.

[0038] The hollow shaft 103 is rotatably supported in the transmission housing 101 by means of a first bearing 109 and a second bearing 111 .

[0039] The lubricant transport ring 113 is located axially between the first bearing 109 and the second bearing 111. The lubricant transport ring is part of the transmission housing 101. A lubricant line 115 passes through the wall of the transmission housing 101 and the lubricant transport ring 113.

[0040] Another lubricant line 117 is formed by the hollow shaft 103. The lubricant line 117 connects the outer circumference of the hollow shaft 117 with the cavity in the interior of the hollow shaft 117 in a lubricant-conducting manner.

[0041] To provide the splines 107 with lubricant, the lubricant is introduced into the lubricant line 115 of the transmission housing 101. The lubricant is transferred to the lubricant line 117 of the hollow shaft 103 at the lubricant transport ring 113. The lubricant line 117 introduces the lubricant into the cavity 117 formed by the hollow shaft.

[0042] Figure 2 The components shown are Figure 1 The difference between the components in is that Figure 2 The assembly in the embodiment has a through-tube 201 and a third bearing 203 instead of the sun shaft 105 and the spline 107. The through-tube 201 is rotatably supported in the hollow shaft 103 by means of the third bearing 203. Here, the third bearing 203 is located in a cavity formed by the hollow shaft 103. Therefore, the third bearing is supplied with lubricant through the lubricant lines 115, 117 and the lubricant transport ring 113 in a manner similar to the spline 107.

[0043] Figure 3 The structure of the lubricant transport ring 113 is shown. The lubricant transport ring 113 is provided with a groove 301. The groove is open radially inward in the direction of the rotation axis of the hollow shaft 103. The groove 301 and the outer peripheral side of the hollow shaft 103 together enclose a cavity. The cavity is used to transfer lubricant from the lubricant line 115 of the transmission housing 101 to the lubricant line 117 of the hollow shaft 103.

[0044] On both sides of the groove 301, a first gap 303 and a second gap 305 extend between the lubricant transport ring 113 and the hollow shaft 103. Lubricant is transferred from the cavity formed by the groove 301 and the outer peripheral side of the hollow shaft 103 through the first gap 303 and the second gap 305. Therefore, no solid friction occurs between the lubricant transport ring 113 and the hollow shaft 103. Therefore, no wear occurs.

[0045] like Figure 4As shown, in order to minimize leakage caused by the discharged lubricant, the first gap 303 and the second gap 305 may be designed as a labyrinth seal.

[0046] from Figure 5 As can be seen from the cross-sectional view of FIG. 1 , the hollow shaft 103 has a pocket 501. The depth of the pocket 501 increases continuously toward the lubricant line 117. As a result, when the hollow shaft 103 rotates, a fluid dynamic effect occurs due to the increase in lubricant pressure at the opening of the lubricant line 117. The increased lubricant pressure causes a pumping effect, which transports the lubricant through the lubricant line 117 into the interior of the hollow shaft 113.

[0047] Reference numerals list

[0048] 101 Transmission housing

[0049] 103 Hollow shaft

[0050] 105 Sun Axis

[0051] 107 Spline

[0052] 109 First Bearing

[0053] 111 Second bearing

[0054] 113 Lubricant transport ring

[0055] 115 Lubricant circuit

[0056] 117 Lubricant circuit

[0057] 201 Through pipe

[0058] 203 Third bearing

[0059] 301 slot

[0060] 303 First Gap

[0061] 305 Second Gap

[0062] 501 pocket

Claims

1. A component comprising a mechanism (101) fixed relative to a housing, a hollow shaft (103) rotatably supported in the mechanism (101) fixed relative to the housing, and a lubrication point (107, 203) at least partially located inside the hollow shaft (103); characterized in that The mechanism (101) fixed relative to the housing has a ring (113), and the ring and the outer peripheral side surface of the hollow shaft (103) enclose a cavity; wherein: The ring (113) has one or more bores (113) respectively opening into the cavity; and, The hollow shaft (103) has one or more bores (117) which each open into the interior of the hollow shaft (103) and into the cavity.

2. The assembly according to claim 1, characterized in that Having a shaft (105); and a spline (107), wherein, The shaft (105) and the hollow shaft (103) are connected to each other in a rotationally fixed manner via the spline (107); and wherein: The spline (107) forms the lubrication point.

3. The assembly according to claim 1, characterized in that A through-tube (201) and at least one bearing (203) are provided, wherein the through-tube (201) is supported in the hollow shaft (103) by means of the bearing; The bearing (203) forms the lubrication point.

4. Assembly according to any one of the preceding claims, characterized in that The ring (113) does not contact the outer peripheral side.

5. Assembly according to the preceding claim, characterized in that One or more labyrinth seals are provided, which seal the ring (113) against the outer peripheral side.

6. Assembly according to any one of the preceding claims, characterized in that The hollow shaft (103) is rotatably supported in the mechanism (101) fixed relative to the housing by means of at least two bearing assemblies (109, 111); wherein: The cavity is arranged axially between the bearing assemblies (109, 111).

7. Assembly according to any one of the preceding claims; characterised in that The hollow shaft (103) and / or the ring (113) have at least one fluid-dynamically acting mechanism (501), which is configured to build up a fluid-dynamic pressure acting on at least one opening (117) of a borehole of the hollow shaft (103) when the hollow shaft (103) rotates.

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