WO2012163556A1

WO2012163556A1 - Rotary union with sealing sleeve

Info

Publication number: WO2012163556A1
Application number: PCT/EP2012/054869
Authority: WO
Inventors: Thomas Wiesneth; Reinhart Malik
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2011-05-31
Filing date: 2012-03-20
Publication date: 2012-12-06
Also published as: DE102011076796A1

Abstract

The invention relates to a rotary union (10) for transferring fluids between at least one first port (29, 30, 31) and at least one second port (32, 33, 34), which is axially offset in relation to the first port, through at least one hub part (27) and through at least one shaft part (28) between the ports (29, 30, 31, 32, 33, 34), said hub part (27) and shaft part (28) being permeable to the fluids. The shaft part (28) and the hub part (27) are rotatable about a rotational axis (11) relative to one another in a transition point, which is radially permeable and axially impermeable to the fluids, between hub part (27) and shaft part (28).

Description

description

Rotary feedthrough with sealing sleeve

Field of the invention

The invention relates to a rotary feedthrough for liquids between at least one first connection and at least one axially offset second connection by at least one liquid permeable hub part and by at least one permeable to the liquid shaft part between the terminals, wherein the shaft part and the hub part on a for the fluids radially permeable and axially sealed transition between the hub part and shaft part relative to each other about an axis of rotation are rotatable.

Background of the invention

An example of a generic rotary feedthrough is described in DE103 29 191A1. Rotary feedthroughs are used, for example, in vehicle transmissions to direct fluids from a stationary arrangement to a further connection via a rotating arrangement or in the opposite direction from connections on the rotating arrangement to the connections of the standing arrangement. One or two annular channels formed in a so-called hub part have connections for pressure medium, through which pressure medium can be directed into the respective annular channel. The respective annular channel runs circumferentially around a metering sleeve, which in turn has a plurality of through holes which are radially overlapped by the annular channel and which are circumferentially adjacent to each other. The annular channel and the dosing sleeve are fixed to each other.

The rotary feedthrough described in DE103 29 191A1 furthermore has a shaft part with a distributor sleeve concentrically fixedly seated on a shaft. The Shaft part is rotatably mounted about a rolling bearing relative to the hub part about the axis of rotation of the shaft.

The transition is the interface between shaft part and hub part, on which the shaft part relative to the hub part and / or the hub part relative to the shaft part is relatively movable. In this case, the transition is a rotational fit carried out with as little radial clearance as possible between the dosing sleeve and the distributor sleeve, on which the dosing sleeve and the distributor sleeve are rotationally movable relative to one another about the axis of rotation. To seal the leakage gap in the radially as possible held tight rotational fit between distributor sleeve and dosing sleeve grinding seals are arranged in the form of 0- rings between the sleeves, which seal the transition against leakage of leakage liquids.

The distributor sleeve has a radial through hole per annular channel, which is designed as a control slot. The radian dimension of the control slot is designed so that in relative rotation and standing in each case at the transition at least one through hole of the dosing sleeve is unlocked over the control slot, so that continuous passage of the liquids is secured by at least one of the through holes and the control slot. The control slots lead radially through the wall of the distributor sleeve to axially oriented passages, which are either designed as radially closed on the bottom side grooves in the distributor sleeve or as grooves in the shaft.

The arrangement according to DE103 29 191A1 is made of shaped sheet metal parts. The formed as grooves passages are relatively expensive chipless or machined to introduce either into the shaft or in the distributor sleeve, because the end and radially limited in one direction grooves of the passages form undercuts that complicate axially directed demolding when forming the sheet metal parts. The seals are designed with O-rings for which radial grooves are also to be provided in one of the components and which also form undercuts. The grooves for the passages in waves are usually milled consuming. The radial dimensions of the rotary feedthrough are determined by the height of the annular channel and the sheet thickness of the sleeves. The O-ring seals require little radial space, so that they are very well suited for sealing the leakage gap at the transition. However, the sliding contact of the radially preloaded O-ring seals over the resulting friction torque significantly determines the torque in the rotary feedthrough. In addition, the seals wear relatively quickly due to their radial bias and the sliding contact and lose the sealing effect.

Description of the invention

The object of the invention is to provide an easy-to-assemble and safe working rotary feedthrough, which requires little radial space, but which can be effectively sealed for a long time with low friction torque and their forming parts are easy to manufacture.

The object is solved according to the subject of claim 1.

The transition is inventively the transition formed by at least one in a radial annular gap radially from the hub part on the one hand and the shaft part on the other hand limited and circumferentially encircling annular chamber. The annular chamber is sealed axially laterally and has the radial dimensions of the annular gap. In comparison to the prior art, therefore, the annular chamber is not arranged radially on the outside of the rotary feedthrough, but at the interface between the shaft and hub part.

The advantage: It is in the transition radially more height for effective seals between the shaft and hub part available without the radial dimensions of the rotary feedthrough compared with the previously known rotary unions had to be increased. In other words - despite the same radial dimensions of the rotary feedthrough is compared to the previously known state of the art more radial height for the formation of suitable low-friction and effective seals available. As seals now radial shaft seals or piston rings are used, which ensure high sealing effects at low friction moments for a long time.

From the annular chamber, at least one first through-hole permeable to the liquids leads radially outwards into the hub part and at least one second through-hole, which is permeable to the liquids, projects radially inwards into the shaft part.

Liquids are all suitable lubricants or coolants that flow through the rotary union with or without pressure. Ports are inputs and / or outputs of any kind, including holes, grooves, grooves, channels, etc.

An embodiment of the invention provides that the first through-hole directed radially outward from the annular chamber is formed in a first metering sleeve and is permeably connected to the first connector for the liquids via at least one first passage. The annular chamber is therefore limited on the outside by a portion of the metering, in which the first through hole is formed. The first passage is formed in this case in a concentric sitting on the first metering sleeve dispensing sleeve. But it is also conceivable that this is formed in the housing.

The axially oriented passage (s) and the through holes or the through hole are therefore no longer housed together in a sleeve but in separate sleeves, as compared with the prior art. This can bring manufacturing advantages, especially if the passages are limited in the distributor sleeve radially in both directions by the surrounding construction and deviating from the previously known prior art in one direction by own material. The passages form the individual part distributor sleeve manufacturing technology instead of elaborate undercuts through holes, which can be easily introduced by punching in the wall of the distributor sleeve. The dosing sleeves and the distributor sleeves are drawn hollow cylindrical components made of sheet metal or hollow sheet metal components wound from flat sheet metal. Axially oriented in this case means that the passages extend in the axial direction and can also expand in the circumferential direction and / or deflect in a spiral or winding shape.

The passage in the first manifold sleeve is radially inward through a portion of the dosing sleeve on which the manifold sleeve is seated and bounded radially outwardly by a portion of a housing in which the manifold sleeve is seated.

A further embodiment of the invention provides that the hub part is a separate assembly formed from the first distributor sleeve and the first dosing sleeve, which can be pre-assembled prior to assembly of the rotary union. For this purpose, the first distributor sleeve is pushed onto the dosing sleeve and then connected to this. Alternatively, the distributor sleeve is pressed onto the dosing sleeve. With such an arrangement, the manufacturer may not need to change his prior art mounting habits, since, as before, despite a further component of the hub part of the invention, only one mounting gear is required to place the hub part in a housing.

Further embodiments of the invention relate to the design of the shaft part. Thereafter, the second through hole is formed in a second dosing sleeve and connected via at least one second passage to the second connection for the liquids permeable. The second passage is analogous to the first passage of the hub part formed in a second distributor sleeve sitting concentrically in the second metering sleeve. Accordingly, the second passage with the advantages already described in the example of the first passage in one direction is not limited by its own material but by components of the surrounding construction. Accordingly, the second passage, with all the advantages already described, does not form an undercut which is relevant for forming technology.

According to one embodiment of the invention, the second passage is radially outward through a portion of the second metering sleeve and radially inwardly through a Surface portion of the second distributor sleeve and the second dosing sleeve bearing shaft limited. The components of the shaft part are advantageously preassembled according to an embodiment of the invention to form a unit, so that the cost of mounting the shaft part at the manufacturer of the transmission despite a part remains low.

The ring seals can optionally be pre-assembled on the structural unit of the shaft part and / or on the structural unit of the hub part.

A further embodiment of the invention provides that the annular chamber is sealed on both sides by at least one seal which has at least one annular seal prestressed radially against one of the parts. The ring seal is preferably a piston ring which generates low friction moments in the sliding sealing contact and is wear-resistant due to its nature of metal compared to the previous O-rings. The brackets for such piston rings are, for example, metal rings with a U-shaped profile, which are easy to manufacture and uncomplicated on / in the corresponding dosing sleeve or press. Alternatively, the brackets are secured by expansion or by welds, by gluing or by other suitable methods. The piston rings are inserted radially elastically yielding in the brackets.

Description of the drawings

FIG. 1 shows a rotary feedthrough 10 in a half section along the axis of rotation 11. Through the rotary feedthrough, lubricating fluid or other pressure medium from a housing 1 along a shaft 8 or along the shaft 8 in the housing 1 of a transmission, not shown in the directions marked with the direction arrows "† j" with the by the line "- x - symbolized course led and distributed.

In the relative to the shaft 8 stationary housing 1 sits a first distributor sleeve 2, which is possibly held by a first metering sleeve 3 in an axial bore 9 of the housing 1 or itself by a press fit in the Axial bore 9 stops. The shaft 8 is rotatable relative to the housing 1 about the axially aligned axis of rotation 1 1. On the shaft 8 is firmly seated a second distributor sleeve 7, which is surrounded by a second dosing sleeve 6. Sitting on the second metering sleeve 6 axially spaced and in this case provided with piston rings 15 ring seals 14th

The ring seals 14 are rotatable with the shaft 8 about the axis of rotation 1 1 and bridge a radial annular gap 16 between the second dosing sleeve 6 and the first dosing sleeve 3. For this purpose sit the ring seals 14 sealingly each in a seal holder 14a and are radially outward against the first Dosing sleeve 3 biased abrasive sealing on the first dosing sleeve 3 radially. The seal holders are, for example, reinforcements of seals, with which the seals are pressed onto the second dosing sleeve 6. Alternatively, the seal holder 14a, the guide rings shown in Figure 1 U-shaped piston rings 15 made of metal or rubber or are plastic rings and thus have both holding functions as well as sealing surfaces or sealing edges. The seal holders 14a are either pressed onto the second metering sleeve 6 and / or axially sealed as shown in FIG. 1 by radially expanded portions 24 of the wall of the metering sleeve 6.

The annular gap 16 is divided by the ring seals 14 into a plurality of, for example three, annular channels 16a, 16b and 16c which are respectively bounded radially inwardly by sections of the second metering sleeve 6 and radially outwardly by sections of the first metering sleeve 3. Axial are the annular channels 16a, 16b and 16c limited by the ring seals 14 and seal holder 14a.

The axially aligned central axes of the annular disk-shaped annular seals 14, the inner cylindrical axial bore 9 and the hollow cylindrical sleeves 2, 3, 6 and 7 correspond to the axis of rotation 1 1 of the shaft eighth

The housing 1 has a plurality of channels 12a to, for example, 12c as the first terminals 29, 30 and 31, of which only one is visible in Figure 1 with the reference numeral 12a. The mouths of the other channels 12b and 12c are hidden in the view and therefore shown in dashed lines. Each channel 12a, 12b and 12c respectively opens into a first passage 13a, 13b or 13c, of which only one is visible in Figure 1 in longitudinal section with the reference numeral 13a and the other passages 13b and 13c hidden in this view and therefore are not visible , The first passages 13 a, 13 b and 13 c are formed in the first distributor sleeve 2

FIG. 2 shows a half section through the hub part 27 designed as a structural unit 21 along the axis of rotation 1 1. The structural unit 21 is formed from the first distributor sleeve 2 and the first metering sleeve 3. During assembly of the assembly 21, the first distributor sleeve 21 was pressed or pushed axially to the radial flange 23 on the dosing sleeve 3. The sleeves 2 and 3 are held together either by a press fit or by, for example, one or more crimping or welding together.

In the illustration according to FIG. 2, the first passages 13b and 13c are concealed and therefore shown in dashed lines. The passage 13a is shown in longitudinal section. Each passage 13a, 13b and 13c is in each case assigned to one of the peripherally adjacent channels 12a, 12b or 12c, of which the mouth is indicated in dashed lines in FIGS. 1 and 2 for the channels 12b and 12c and the channel 12a is shown in longitudinal section in FIG.

Each of the passages 13a, 13b, and 13c respectively leads from one of the passages 12a, 12b, or 12c to at least one radial first through-hole 17a, 17b, and 17c in the first dosing sleeve 3. Of the through-holes 17a, 17b, and 17c, in FIG only the first through hole 17a in longitudinal section visible, but in Figure 2, the first through hole 17c are complete and the first through hole 17b partially shown. It is also conceivable that at least two of the first through-holes 17a, 17b or 17c in the first dosing sleeve 3 are associated with each of the passages 13a, 13b and / or 13c. The through-holes 17a, 17b and 17c lead radially from each one of the passages 13a, 13b or 13c through the first metering sleeve 3 into one of the annular channels 16a, 16b or 16c. Each of the annular channels 16a, 16b and 16c is assigned in each case at least one radial second through-hole 18a, 18b or 18c in the second dosing sleeve 6. Each of the second through holes 18a, 18b or 18c leads to a second passage 19a, 19b or 19c in the manifold sleeve 7, respectively. Alternatively, two or more of the second through holes may collectively lead into one of the second passages. The second passages 19a, 19b or 19b are axially aligned in this case, but may also be deflecting in the circumferential direction. Of the second through holes 18a, 18b or 18c and of the second passages 19a, 19b or 19c, only one is shown in FIG.

FIG. 3 shows a half section through the shaft part 28 designed as a second structural unit 22 along the axis of rotation 11. The second unit 22 is formed from the second metering sleeve 6, the second distributor sleeve 7 and the ring seals 14 with seal holders 14 a and piston rings 15. The seal holder 14a are applied, for example, by rolling on the second metering sleeve 6, wherein the wall of the metering sleeve 6 is radially expanded at the portions 6a. Subsequently, the so pre-assembled assembly of seal holder 14a and second metering 6 is pushed axially onto the second distributor sleeve 7 to the collar 25 of the second distributor sleeve 7 or pressed.

In FIG. 3, the second passage 19a is shown in longitudinal section, the second passage 19b is completely and the second passage 19c partially shown.

Each of the passages 19 a, 19 b and 19 c is assigned at least one third through-hole 20 a, 20 b or 20 c in the second dosing sleeve 6. The radial third through holes 20a, 20b and 20c are formed in the second metering sleeve 6 at an axial distance in line or circumferentially offset from the second through holes 18a, 18b or 18c and lead from the respective passage 19a, 19b or 19c through the second metering sleeve 6 through as second terminals 32, 33 and 34 to not shown lubrication points on gears, bearings or other Transmission elements. It is also conceivable that the second dosing sleeve 6 has more than one of the third through holes per passage.

Figure 4 shows a cross section through the rotary feedthrough 10 and thus transversely through the housing 1 and thereby through the channel 12a in the housing 1, further across the passage 13a in the first distributor sleeve 2 at the axial height of the through hole 17a in the first dosing sleeve 3 across the through-hole 17a, further across the circumferential annular channel 16a between the first dosing sleeve 3 and the second dosing sleeve 6 axially at the level of the through-holes 18a in the second dosing sleeve 7 and across the through-hole 18a and finally further across the passages 19a in the second distributor sleeve 7 and as a full section through the shaft 8. The annular seal 14 is seated in this representation to the image plane set back in the annular gap 16 between the first dosing sleeve 3 and the second dosing sleeve. 6

The double arrow symbolizes possible rotational or pivoting directions of the shaft 8 about its axis of rotation 1 1, which is directed perpendicular to the image plane in this case. Separation point between the rotating second assembly 22 relative to the housing-fixed assembly 21 is the circular inner body edge 26 of the housing-fixed first distributor sleeve 3, on which the ring seal 14 rotates along rotating.

reference numeral

Housing 18a second through hole first manifold sleeve 18b second through hole first metering sleeve 18c second through hole

Piston rings 19a second passage

Piston ring guide 19b second passage second metering sleeve 19b second passable wall portion 20a third through hole second manifold sleeve 20b third through hole

Shaft 20c third through hole

Axial bore 21 first unit0 Rotary feedthrough 22 second unit 1 Rotation axis 23 Flange

2a channel 24 widened parts2b channel 25 collar

2c channel 26 body edge

3a first passage 27 hub part

3b first passage 28 shaft part

3c first passage 29 first port 4 ring seal 30 first port 4a seal holder 31 first port 5 piston ring 32 second port 6 annular gap 33 second port 6a annular channel 34 second port 6b annular channel

6c ring channel

7a first through hole

7b first through hole

7c first through hole

Claims

claims

1 . Rotary feedthrough (10) for liquids between at least one first connection (29, 30, 31) and at least one axially offset to this second connection (32, 33, 34) by at least one liquid permeable hub part (27) and at least one for the fluid permeable shaft portion (28) between the terminals (29, 30, 31, 32, 33, 34), wherein the shaft portion (28) and the hub portion (27) at a radially permeable and axially sealed transition between the hub part (27) 27) and shaft part (28) relative to each other about an axis of rotation (1 1) are rotatable, characterized in that the transition through at least one in a radial annular gap (16) radially from the hub part (27) on the one hand and of the shaft part (28) on the other hand limited and axially laterally sealed and circumferentially encircling annular chamber (16a, 16b, 16c) is formed, which has the radial dimensions of the annular gap (16) and of we Lich from at least one liquid-permeable first through hole (17a, 17b, 17c) into the hub part (27) and at least one liquid-permeable second through hole (18a, 18b, 18c) in the shaft part (28).

2. Rotary feedthrough according to claim 1, characterized in that the first through hole (17 a, 17 b, 17 c) formed in a first dosing sleeve (3) and at least a first passage (13 a, 13 b, 13 c) with the first port (29, 30 , 31) is permeably connected to the fluids, the first passage (13a, 13b, 13c) being seated in a distributor sleeve (2) seated concentrically on the first metering sleeve (3).

3. Rotary feedthrough according to claim 2, characterized in that the annular chamber (16 a, 16 b, 16 c) is bounded radially outwardly by a portion of the first dosing sleeve (3).

4. Rotary feedthrough according to claim 2, characterized in that the first passage (13 a, 13 b, 13 c) radially inwardly through a portion of the first dosing sleeve (3) and radially outwardly by a portion of a housing (1) is limited, in which the first Distributor sleeve (2) sits.

5. Rotary feedthrough according to claim 2, characterized in that the hub part (27) from the first distributor sleeve (2) and the first dosing sleeve (3) formed separate first assembly (21), wherein the first distributor sleeve (2) fixed on the first dosing sleeve (3) sits.

6. Rotary feedthrough according to claim 1, characterized in that the second through hole (18a, 18b, 18c) formed in a second metering sleeve (6) and at least a second passage (19a, 19b, 19c) with the second port (32, 33 , 34) is permeable to the fluids, the second passage (19a, 19b, 19c) being formed in a second distributor sleeve (7) concentrically seated in the second metering sleeve (6).

7. Rotary feedthrough according to claim 6, characterized in that the annular chamber (16 a, 16 b, 16 c) is bounded radially inwardly by a portion of the second dosing sleeve (6).

8. Rotary feedthrough according to claim 6, characterized in that the second passage (19 a, 19 b, 19 c) radially outwardly through a portion of the second dosing sleeve (6) and radially inwardly through a surface portion of a second distributor sleeve (7) and the second dosing sleeve ( 6) supporting shaft (8) is limited.

9. Rotary feedthrough according to claim 6, characterized in that the shaft part (28) at least from the second metering sleeve (6) and the second distributor sleeve (7) formed second assembly (22), wherein the second metering sleeve (6) concentric on the second distributor sleeve (7) sits.

10. Rotary feedthrough according to claim 1, characterized in that the annular chamber (16 a, 16 b, 16 c) on both sides by at least one annular seal (14) is sealed, wherein the ring seal (14) at least one radially against one of the parts prestressed ring (15 ), which is held radially elastically movable axially in a on one of the parts (27, 28) seated seal holder (14 a).