DE102011009564A1 - Bearing unit for shaft of turbo charger, has outer ring, inner ring and two bearing series guided between outer ring and inner ring - Google Patents

Abstract

The bearing unit has an outer ring (10), an inner ring (12a) and two bearing series guided between the outer ring and the inner ring. A channel (28) is provided between the outer ring and the inner ring to inject lubricant into an intermediate space (14). A device is provided to separate the lubricant from dirt particles using the centrifugal force. An independent claim is also included for a turbo charger.

Description

Field of the invention

The invention relates to a bearing unit for turbocharger spindle units, also referred to below as TLSE, according to the preamble of claim 1.

State of the art

Exhaust gas turbochargers are operated at very high speeds at high temperatures. On a common shaft, a turbine and a compressor are arranged. These operating conditions place high demands on the accuracy and wear resistance of the bearing unit of the bearing of the shaft. Typical TLSEs are for example in DE 20 2004 017 194 U1 and DE 38 25 326 A1 disclosed. The bearing unit is designed as a rolling bearing. The rolling bearing includes, for example, an outer ring with two rows of bearings and two inner rings, each with a bearing row. The distances of the raceways between the outer ring and the inner ring have a well-defined difference to produce a tendency to employment; Preferably, an O-arrangement is used.

Due to the high temperatures and speeds, the TLSE must be permanently supplied with lubricant. The lubricant, typically oil, is supplied to the TLSE through two holes in the outer ring. These two holes are inclined to the bearing rows to ensure a good supply of the bearing rows with lubricant. Since the turbocharger is used in internal combustion engines, the TLSE is advantageously included in the lubrication circuit of the internal combustion engine. As a lubricant for the TLSE thus the engine oil of the internal combustion engine is used. In addition to lubrication, the engine oil also performs a cooling function.

The quality of the engine oil in an internal combustion engine decreases sharply during operation. As the oil is also used for the lubrication of the TLSE, it is above all pollution caused by abrasion and combustion residues that can impair the safe functioning of the TLSE. During operation of the TLSE, very high forces, temperatures and rotational speeds act, which put a heavy strain on the TLSE. To ensure the required service life of the TLSE, a good lubricant supply with good lubricant quality is advantageous. Conventional filters for cleaning the engine oil, which are placed in the TLSE before the engine oil enters, settle very quickly and throttle the lubricant circuit. Such upstream filters have therefore not proven.

A common cause of ball bearing failure is the failure of the ball bearing cage. The cage is typically guided on the inboard or outboard and has the task of keeping the rolling elements, here balls, at a distance from each other in order to achieve the most even distribution of the ball on the circumference. Typically, the ball pockets wear in the circumferential direction and the respective guide surface on the inner or outer ring. Large forces and high relative speeds increase the tendency to wear. The largest forces and relative velocities occur especially in the acceleration phases. Due to the paddle wheels (turbine wheel and compressor wheel), the direction of rotation is predetermined for the turbocharger - the turbocharger only turns in one direction. The forces on the cage, the u. a. caused by the inertia of the cage and the frictional forces in the contact points with adjacent components, as well as the fluid friction of the lubricant must be overcome. For this purpose, energy must be supplied to the cage. The energy is supplied via the balls and possibly via the inner or outer ring (if the cage is guided over the rotating ring). When energizing through the ball, the damaging "skidding effect" can be amplified, with the balls due to sliding friction instead of rolling friction. slipping on the ring. By reducing or avoiding the "skidding effect", the wear of the bearing unit in general, in particular also the wear on the cage, can be reduced or avoided in order to increase the service life of the entire bearing unit or of the entire turbocharger.

Disclosure of the invention

The object of the invention is therefore to significantly reduce the wear in a bearing unit for turbocharger spindle units, and thus to increase the life and to improve the reliability.

The object is achieved by a storage unit having the features of claim 1.

Preferred embodiments of the invention and further advantageous features are specified in the subclaims.

The bearing unit for a shaft of a turbocharger comprises at least one outer ring, at least one inner ring and at least two bearing rows guided between outer ring and inner ring. At least one channel is provided for injecting lubricant into a space between the outer ring and the inner ring.

The invention is characterized in that within the space and / or on Inner ring and / or the outer ring means are arranged, which separate the lubricant using lubricant located in the lubricant using centrifugal force.

According to the invention, the different specific gravity of the dirt particles is utilized in comparison to the pure motor oil. After the engine oil has entered the TLSE, the lubricating medium strikes the rotating component, for example the inner ring, and is thereby set in rotation and finally thrown off in the direction of the non-rotating component, for example the outer ring. The predominantly determined by the centrifugal force trajectory of the thrown dirt particles differs from the trajectory of pure engine oil due to the different specific weights and the different inertia. By introducing suitable geometries on the rotating component and / or the non-rotating component, but also in the flow channel, the dirt particles can be completely or at least partially removed from the engine oil by utilizing the centrifugal force.

According to a preferred embodiment of the invention, the lubricant containing dirt particles, for example engine oil, reaches the outer diameter of the rotating inner ring through specifically oriented feed channels. The channels preferably extend at an angle of about 60 ° to 80 ° to the shaft axis of the shaft and open in the vicinity of an associated bearing row. The inner ring has in the impact zone of the lubricant a special geometry in the form of, for example, a defined groove possibly with Abspritzkante. By hitting the rotating inner ring, the oil itself is set in rotation and finally thrown off and hits the board of the fixed outer ring. By centrifugal forces acting on the lubricant and the dirt particles therein, the dirt particles are deflected by their higher inertia at a different angle than the pure lubricant and meet in a different area on the outer ring than the pure lubricant. By a suitable geometry in the outer ring, z. B. a defined groove with separating edge, the dirt particles can be separated from the oil. The at least partially freed of the dirt particles lubricant can then be fed directly to the bearing rows, while the contaminant-enriched lubricant is directed away from the bearing rows.

According to a preferred embodiment of the invention, a nebulization / atomization of the lubricant is performed. By optimizing the parameters of the oil supply, such. As volume flow, pressure, direction, speed of the component, on which the jet impinges, introducing a Abspritzkante for atomizing the oil, a vortex flow of the atomized lubricant is generated, which transports the lubricant mist to the bearing rows. A nebulization can also be achieved by a corresponding design of the oil supply channels. In this case, at least a part of the supplied lubricant is atomized or atomized. The bearing rows are thus lubricated with oil mist. The formation of mist (droplet formation) separates the dirt from the "clean" oil. The non-aerosolized, contaminated part of the oil does not get into the bearing rows, leaves the TLSE through the oil outlet hole, but remains in the lubricant circuit and is available for cooling ,

According to a further preferred embodiment of the invention, the flow energy of the lubricating oil can be used to reduce wear, in particular on the cage. The oil supply channels inclined toward the ball bearing are inclined not only in relation to the longitudinal axis of the shaft but additionally in the circumferential direction of the outer ring and positioned so that the lubricant jet hits the cage directly or indirectly, thereby driving the cage in its intended direction of rotation.

Preferably, the flow of lubricant should impact the cage in an area that will well drive the cage, not interfere with the cage, and support its stable travel. Preferably, this may be the cage side. For better conversion of the flow energy of the lubricant into kinetic energy of the cage, corresponding contours or baffles may be mounted on the cage or in the cage. It can z. B. paddle wheels on the lubricant flow facing end face of the cage can be arranged. As an alternative to the direct impact of the oil jet on the cage, the oil jet can first strike the rotating component (eg inner ring) and then impinge on the cage, ie impinge indirectly. This nebulizes the lubricant and hits in many small droplets on the cage, which is gentler for the cage. In addition, inconstant volumetric flows of the oil become more uniform. The impact of the oil jet on the inner ring (or the shaft) causes an angular momentum to be transmitted to the lubricant, which favors the drive of the cage.

Inner ring guided cages tend to heat up on the side facing away from the lubricant introduction and wear out quickly, because too little lubricant reaches the sliding guide. The heat input with heating of the bearing row to a very high temperature level is unfavorable for the function and the life of the bearing. Better lubrication to reduce friction and a reduction in the temperature of the bearing row are therefore advantageous. The cooling by means The engine oil is insufficiently effective for the turbine-side bearing row.

A further preferred embodiment of the invention provides to design the geometry of the cage asymmetrically. As a result, the friction on the cage guide can be substantially reduced. Due to the novel cage geometry, the lubricant is brought completely over the bearing point using centrifugal forces via a bevel and then thrown to the outside to lubricate the bearing over the rolling elements, and in addition to the opposite leadership of the cage, there too sufficient lubrication ensure, especially if the entry of the lubricant can only be done on one side. The described measures and effects lubricant is transported in a typical manner to previously poorly lubricated areas of the ball bearing.

In addition, the "open", d. H. for the flow of the lubricant free cross-sections enlarged. This reduces the "filter action" of the bearing row, which reduces the likelihood of contamination from the lubricating oil in the bearing row. Impurities could get into the track - ball - contact or into the contact points of the cage with neighboring components and produce there increased running noise or high mechanical stresses. The reduction or avoidance of contamination entry into the storage rows is thus very advantageous for trouble-free operation and longevity of storage.

In addition, the new geometry reduces the weight of the cage by reducing the cage volume. Thus, the moment of inertia is reduced, which promotes rapid acceleration and deceleration.

Further, in the novel geometry, the weight of the cage is balanced, because despite the asymmetric cage geometry (cross-section), the masses are symmetrically distributed, reducing the likelihood of dynamic imbalance occurring. To avoid heating the bearing to a too high temperature level, the bearing row is better and more lubricated with respect to the temperature flow due to the special geometry of the cage. As a result, the heat is transferred to the lubricant and transported away from the bearing. In addition, the favorable removal of the lubricant prevents or reduces "churning losses" in the bearing row. The asymmetrical ball cage achieves improved lubrication and higher heat dissipation of the bearing row, which increases the life and function of the complete unit.

As an additional feature, the sliding guides of the cage, so z. B. cage-bearing ring contact and cage-ball contact) be provided with a friction reducing layer such. As a silver layer, a DLC layer or the like.

In a further preferred embodiment of the invention, the lubricant contaminated with dirt particles, a swirl (angular momentum) are added, resulting in an eddy current and the dirt particles are transported by centrifugal force to the outside to the edge of the eddy current. The by centrifugal force transported radially outward offset with dirt particles lubricant can then be discharged through radially outwardly mounted drainage devices, for example in the simplest case through a hole. In the middle of the turbulent flow, ie in the core of the lubricant supply flow, the "cleaned" lubricant remains and can then be supplied to the storage system or the ball bearing row for lubrication. The angular momentum in the lubricant flow can be generated, for example, by guide blades which are inclined relative to the flow, by tangential flow, by threaded channels or oblique incident flow. The swirl generation can be arranged both in the bearing unit itself and in the channels for the lubricant supply, for example, in the housing of the turbocharger. The cleaning of the lubricant by means of angular momentum is thus possible within the dimensions of the turbocharger, d. H. integrated into the turbocharger or its storage unit, so that no further component to be mounted outside the storage unit or the turbocharger is needed.

In the following the invention will be explained in more detail with reference to several embodiments with reference to the drawings. The drawings and the description of the drawing provide further features and advantages of the invention.

Brief description of the drawings

1 shows a section through a first embodiment of the storage unit according to the invention.

2 : shows an enlarged section in the area of the left bearing row.

2a shows a modified embodiment of the groove 32 out 2 ,

3 shows a section through a second embodiment of the storage unit according to the invention.

4 : shows an enlarged section in the area of the left bearing row.

5 : shows a simplified section through a part of a bearing unit according to a third embodiment of the invention.

6 shows a simplified section through a part of a storage unit according to a fourth embodiment of the invention.

7 shows a section through a fifth embodiment of a storage unit according to the invention.

7a , b: shows a bearing cage in perspective and in section

8th shows a schematic section through a storage unit according to another embodiment of the invention.

9 FIG. 11 is an enlarged view of the lubricant supply passage shown in FIG 8th ,

10 Fig. 1 shows schematically a section through the channel for supplying the lubricant according to a further embodiment for generating a swirl of the lubricant.

11 Fig. 1 shows schematically a section through the channel for supplying the lubricant with tangential flow to produce a twist.

12 Fig. 1 shows schematically a section through a channel with spiral geometry for generating a twist of the lubricant.

DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

In 1 is a storage unit with two ball bearing rows, which are designed here as a shoulder ball bearing, shown according to the invention. The bearing unit comprises a one-piece outer ring 10 and a spaced apart two-part inner ring 12a , b. Between the outer ring 10 and the inner ring 12a , b remains a gap 14 in which the bearing rows are arranged, which are arranged at a large distance from each other. The inner ring 12a , b is stuck with a wave 16 connected to a shaft axis 18 rotates.

A first row of bearings comprises a ball cage 20 who has a variety of balls 22 contains. The second row of bearings also includes a ball cage 24 who has a variety of balls 26 contains. The balls 22 . 26 run in corresponding raceways of the outer ring 10 or the inner rings 12a . 12b ,

Lubrication and at the same time cooling of the bearing unit is carried out by a lubricant, which has corresponding channels 28 in the gap 14 is injected near the bearing rows. As a lubricant, an engine oil of an oil circuit of an internal combustion engine is preferably used. The channels 28 are at an angle of about 60 ° to 80 ° with respect to the shaft axis 18 the wave 16 in the outer ring 10 provided, so that the lubricant is injected obliquely in the direction of the respective rows of bearings.

2 shows an enlarged view of the storage unit 1 in the area of the left bearing row. You can see the outer ring 10 , the inner ring 12a and the balls in between 22 coming from the ball cage 20 being held. The inner ring sits on the shaft 16 around a shaft axis 18 rotates. About the channel 28 The lubricant is at an oblique angle in the direction of the inner ring 12a injected. The lubricant flow 40 meets in a first area 30 on the inner ring 12a in which, according to this embodiment, a defined groove 32 is arranged. How to get in 2a can recognize this groove 32 also with a spray edge 32a be provided. Because the inner ring 12a and thus also the groove 32 with the wave 16 The lubricant flow will also rotate 40 set in rotation and from the groove 32 deflected and thrown off in the direction of the outer ring 10 , The lubricant flow then hits the inner diameter of the outer ring 10 , By acting on the lubricant and the particles contained therein centrifugal forces, the dirt particles are deflected more clockwise according to the drawing representation as the pure lubricant, so that the pure lubricant according to the flow 40a in a second area 34 on the outer ring 10 impinges, while the dirt particles are deflected more clockwise and according to the flow pattern 40b in a third area 36 on the outer ring 10 incident. To separate the pure oil better from the dirt-laden oil is a separating edge 38 at the inner diameter of the outer ring 10 intended.

The 3 and 4 show a storage unit, which is essentially in the 1 and 2 shown storage unit corresponds. The same components are provided with the same reference numerals and the general description of the storage unit also applies to the storage unit of 3 and 4 ,

In contrast to the first embodiment is in the embodiment according to 3 on the inner ring 12a . 12b no groove provided, but at the outer diameter of the inner ring 12a , b are corresponding baffles 42 intended.

In the enlarged view of the left bearing part according to 4 you realize that the baffle 42 arranged and angled so that that through the channel 28 Injected lubricant according to the illustrated lubricant flow 44 on the rotationally symmetrical baffle plate 42 impinges and is atomized by the injection pressure. The degree of atomization can be controlled by various parameters, in particular by the volume flow, the pressure, the direction of the injected lubricating oil and the speed of the inner ring 12a , b and thus the speed of the baffle plate 42 , Characterized in that the lubricant obliquely in the direction of the baffle plate 42 is injected, it experiences both a velocity component in the direction of the balls 22 as well as a velocity component in the circumferential direction due to the rotation of the inner ring 12a or the baffle plate 42 around the shaft axis 18 , It becomes a first course of flow 44a produces the atomized lubricant that carries the lubricant mist to the bearing row. The bearing rows are thus lubricated with atomized lubricant. The dirt particles follow the course of the flow 44b and are deflected by centrifugal forces in a clockwise direction according to the drawing representation and do not reach the area of the bearing rows.

5 schematically shows a further embodiment of a storage unit according to the invention with an outer ring 110 , an inner ring 112a and balls in between 122 with ball cage 120 , About a channel 128 becomes a lubricant according to the lubricant flow 140 in the gap 114 injected and meets in a first area 130 on one on the inner ring 112a arranged rib 132 , Due to the oblique injection and the rotation of the inner ring 112a with the rib 132 the injected lubricant is swirled and exposed to centrifugal forces, the lighter parts, so the pure lubricant, according to the flow 140a flows in the direction of the bearing row, while the heavier debris in a clockwise direction according to the drawing representation of the flow 140b following the rib and the rib 132 do not overcome. In the direction of the shaft axis 18 offset to the rib 132 is on the outer ring 110 another rib 138 arranged, which the lubricant flow 140 in the flow course 140a brakes and, if appropriate, restrains further dirt particles, which are then moved by the centrifugal forces, which are directed radially outwards in the direction of the outer ring 110 act in the area of this rib 138 being held.

6 shows an embodiment of a storage unit according to the invention in detail, which essentially according to the embodiment 5 equivalent. Identical components are designated by the same reference numerals.

In contrast to 5 is at 6 on the inner ring 112a a cross-sectionally approximately rectangular rib 232 arranged, which performs substantially the same function as the rib 132 in 5 , In 5 was the rib 132 provided with rounded edges.

On the outer ring 110 is according to 6 also a rib 238 present, which is offset to the rib 232 is arranged and one in the direction of the rib 232 open undercut 242 having. This undercut should collect any dirt particles that are the first rib 232 overcome in the direction of the bearing row and by the radially outward centrifugal forces in this undercut 242 be kept and not get further to the bearing row. The flow course 240a of the lubricant and the flow pattern 240b the dirt particle is shown by the arrows.

In particular, in the embodiment according to the 1 and 2 There is the further advantage that by the directed to the bearing row flow 40a the purified lubricant this flow energy of the lubricant is used to the ball cage 20 to drive in its intended direction of rotation.

It is advantageous if the channel 28 for injecting the lubricant not only to the shaft axis 18 the wave 16 is tilted, but also in the circumferential direction of the outer ring 10 is inclined, so that the lubricant through the deflection by the inner ring 12a on the separating edge and then the ball cage 20 meets and the ball cage 20 in the direction of rotation drives.

Of course, it can also be provided that the channel 28 or the outlet of the channel 28 is directed directly onto the ball cage, so that the higher flow velocity, compared to the indirect flow, the ball cage is accelerated much more. However, in this embodiment, the groove would have to 32 in the inner ring 12a or the separating edge 38 omitted on the outer ring, so that the dirt particles separating effect of these facilities would no longer exist.

In 7 a bearing unit is shown with two ball bearings, which in their structure essentially the bearing units from the 1 and 3 equivalent. The bearing unit comprises a one-piece outer ring 310 and a spaced apart two-part inner ring 312a . 312b , Between the outer ring 310 and the inner ring 312a , b remains a gap 314 in which the bearing rows are arranged at a great distance from each other. The inner ring 312a , b can be fixedly connected to a shaft (not shown) and rotated about a shaft axis 318 , A first row of bearings comprises a ball cage 320 who has a variety of balls 322 contains. The second stock line includes also a ball cage 324 who has a variety of balls 326 contains. The balls 322 . 326 run in corresponding raceways of the outer ring 310 or the inner rings 312a . 312b ,

The lubricant is through appropriate channels 328 in the gap 314 injected in the vicinity of the two rows of warehouses and can the space through an outlet 346 leave.

According to this embodiment of the invention, the ball cages 320 and 324 formed asymmetrically in cross section. The cross section of the ball cage comprises a longer leg and a shorter leg, which are arranged at an obtuse angle to each other. The tip of the angle points towards the outer ring 310 , The longer leg lies in the direction of the canal 328 through which the lubricant is introduced. The one through the channels 328 introduced lubricant flow 340 first meets the inner ring 312a . 312b on. Because the inner ring 312a . 312b rotates during operation of the bearing, the lubricant flow 340 set in rotation and by the inner ring 312a . 312b in the direction of the outer ring 310 spun off. The lubricant flow then hits the inner diameter of the outer ring 310 , Due to the asymmetry of the ball cages 320 . 324 remains between the legs of the ball cages 320 . 324 and the outer ring 310 a continuous gap. The lubricant flow can now easily penetrate into the intermediate space and the balls flow around and thus reaches all important lubrication points.

The design of the ball cages 320 . 324 has another effect. Due to the centrifugal forces acting on the lubricant and the dirt particles contained therein, the lubricant and the dirt particles are deflected to different degrees. The pure lubricant preferably reaches the lubrication points, while the dirt particles are largely directed away from the bearing rows.

In 7a and 7b is an example of a possible embodiment of the ball cages 320 . 324 shown.

8th schematically shows a section through a further embodiment of a storage unit according to the invention. The bearing unit comprises an outer ring 410 and an inner ring spaced therefrom 412a , being between the outer ring 410 and the inner ring 412a a gap 414 remains in which rolling elements, in this case balls 422 , are arranged. The balls 422 are preferably in a ball cage 420 held and run on corresponding raceways in the inner ring 412a or outer ring 410 are arranged. The inner ring 412a sits, for example, on a shaft, which is not shown in this drawing.

Lubrication and at the same time cooling of the bearing unit or the balls 422 is done by a lubricant that has a corresponding channel 428 in the gap 414 is injected, wherein as a lubricant preferably an engine oil of an oil circuit of an internal combustion engine is used. The channel 428 for injecting the lubricant is arranged at an angle with respect to the longitudinal axis of the bearing unit, so that the lubricant obliquely in the direction of the respective rolling elements 422 is supplied.

The outer ring 410 is in a housing 448 arranged. About a channel 450 the lubricant is in the channel 428 in the outer ring 410 initiated. Either in the channel 450 or at the beginning of the channel 428 There are facilities that the incoming lubricant flow 440 give a twist. This angular momentum of the lubricant about the flow axis causes a centrifugal force acting on the lubricant. The lubricant contains dirt particles, in particular metallic abrasion due to wear or combustion residues whose specific density is greater than the density of the lubricant. Due to the centrifugal force acting on the lubricant mixed with dirt particles, these "heavier" dirt particles are separated from the pure lubricant due to the centrifugal forces acting on them. The higher density contaminants migrate outward due to the higher centrifugal forces in the rotating lubricant flow. They displace the lower density components, ie the pure lubricant, which thereby reaches the center, while the dirt particles migrate to the outside. In the channel 428 Thus, the pure lubricant is separated from the contaminated lubricant. While the pure lubricant through a centric bore 452 in the gap 414 passes and for lubrication of the balls 422 can be used, the dirt-laden lubricant, which is located radially outward in the channel 428 stops over another hole 454 dissipated and the gap 414 fed at a different angle, so that it does not get into the area to be lubricated.

The generation of an angular momentum of the lubricant can be achieved in various ways.

9 shows, for example, the supplied lubricant flow 440 who is the channel 428 is supplied. On the outer wall of the channel are arranged obliquely to the axis of the channel vanes 456 provided on the the lubricant flow 440 meets and thereby in a lubricant flow with angular momentum 440a is offset. By the angular momentum For example, the heavier debris is transported radially outward while the pure lubricant remains in the center of the lubricant flow and over the bore 452 as lubricant flow 441 can flow out while the enriched with dirt particles lubricant flow 444 via a lateral bore 454 can drain away.

In 10 Another possibility for generating an angular momentum on the lubricant is shown. It can be seen schematically the outer ring 410 with the channel 428 for introducing the lubricant and a part of the housing 448 , which rests on the outer ring. About another channel 450 becomes the lubricant flow 440 obliquely with respect to the canal 428 introduced, so that the lubricant is thereby twisted and lubricant flow with angular momentum 440a forms. The heavier debris thus migrates radially outward and to the edge of the channel 428 while the lighter lubricant in the middle of the channel 428 remains. A separation of the two components can, for example, as in 9 be performed and is in 10 not shown.

11 shows an embodiment of the swirl generation by tangential flow. Schematically, the outer ring 410 with channel 428 shown from above, wherein the lubricant flow 440 the channel 428 through the channel 450 is supplied tangentially and thereby a rotating lubricant flow with angular momentum 440a forms. This lubricant flow with angular momentum 440a can then be used accordingly.

12 schematically shows a section through the outer ring 410 in the area of the supply of the lubricant flow 440 , wherein the lubricant flow through a threaded hole 458 is supplied and thereby receives an angular momentum (spin) and forms a lubricant flow with angular momentum.

LIST OF REFERENCE NUMBERS

10

outer ring

12a, b

inner ring

14

gap

16

wave

18

shaft axis

20

ball cage

22

Bullet

24

ball cage

26

Bullet

28

channel

30

first area

32

groove

32a

Abspritzkante

34

second area

36

third area

38

separating edge

40

lubricant flow

40a, b

flow path

42

baffle

44

lubricant flow

44a, b

flow path

110

outer ring

112a

inner ring

114

gap

120

ball cage

122

Bullet

128

channel

130

first area

132

rib

138

rib

140

lubricant flow

140a, b

flow path

232

rib

238

rib

240

lubricant flow

240a, b

flow path

242

undercut

310

outer ring

312a, b

inner ring

314

gap

318

shaft axis

320

ball cage

322

Bullet

324

ball cage

326

Bullet

328

channel

340

lubricant flow

346

outlet

410

outer ring

412a

inner ring

414

gap

420

ball cage

422

Bullet

428

channel

440

lubricant flow

440a

Lubricant flow with angular momentum

441

Lubricant flow (cleaned)

444

Lubricant flow (contaminated)

448

casing

450

channel

452

drilling

454

drilling

456

vane

458

threaded hole

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 202004017194 U1 [0002]
• DE 3825326 A1 [0002]

Claims (21)

Bearing unit for a shaft ( 16 ) of a turbocharger having at least one outer ring ( 10 ; 110 ; 310 ; 410 ), at least one inner ring ( 12a , b, 112a ; 312a , b; 412a ) and at least two bearing rows guided between outer ring and inner ring, wherein at least one channel ( 28 ; 128 ; 328 ; 428 ) for injecting lubricant into a gap ( 14 ; 114 ; 314 ; 414 ) is provided between the outer ring and the inner ring, characterized in that means ( 32 . 38 . 42 . 132 . 138 . 232 . 238 . 242 ; 320 . 324 ; 428 ; 456 . 458 ) are provided, which separate the lubricant from lubricant particles in the lubricant by utilizing the centrifugal force. Bearing unit according to claim 1, characterized in that the devices ( 32 . 38 . 42 . 132 . 138 . 232 . 238 . 242 ; 320 . 324 ) within the space ( 14 ; 114 ; 314 ; 414 ) are arranged between the outer ring and the inner ring. Bearing unit according to claim 1, characterized in that the devices ( 32 . 38 . 42 . 132 . 138 . 232 . 238 . 242 ; 428 ; 456 ; 458 ) are arranged in or on the inner ring and / or in or on the outer ring. Bearing unit according to claim 1, characterized in that the devices are part of an intermediate space ( 314 ) arranged ball cage ( 320 . 324 ) are. Bearing unit according to one of claims 1 to 4, characterized in that the channel ( 28 ; 128 ; 328 ; 428 ) for injecting the lubricant into the space ( 14 ; 114 ; 314 ; 414 ) in the stationary outer ring ( 10 ; 110 ; 310 ; 410 ) is arranged. Bearing unit according to one of claims 1 to 5, characterized in that the channel ( 28 ; 128 ; 328 ; 428 ) at an angle of about 60 ° to 80 ° to the longitudinal axis of the outer ring ( 10 ; 110 ; 310 ; 410 ) and opens in the vicinity of a bearing row. Bearing unit according to one of claims 1 to 6, characterized in that the channel ( 28 ; 128 ; 328 ; 428 ) on the rotating inner ring ( 12a , b; 112a , b; 312a , b), and the lubricant in a first area ( 30 ; 130 ) on the inner ring ( 12a , b; 112a ; 312a , b; 412a ) and is accelerated by the rotation of the inner ring in the circumferential direction. Bearing unit according to one of claims 1 to 7, characterized in that the inner ring ( 12a , b) in the first area ( 30 ) a substantially perpendicular to the shaft axis ( 18 ) the wave ( 16 ) running groove ( 32 ), the lubricant in the direction of the outer ring ( 10 ) redirects. Bearing unit according to claim 8, characterized in that the groove ( 32 ) a Abspritzkante ( 32a ), at which the deflected lubricant from the inner ring ( 12a , b) replaces. Bearing unit according to claim 8 or 9, characterized in that due to the acceleration of the lubricant and the deflection by the groove ( 32 Centrifugal forces acting on the lubricant, whereby the lubricant at a first angle in the direction of the outer ring ( 10 ) and in a second area ( 34 ) on the outer ring ( 10 ), while enriched with dirt particles lubricant is deflected at a second angle in the direction of the outer ring and in a third area ( 36 ) on the outer ring ( 10 ). Bearing unit according to one of claims 1 to 10, characterized in that the outer ring ( 10 ) between the second area ( 34 ) and the third area ( 36 ) a substantially perpendicular to the shaft axis ( 18 ) of the shaft extending separating edge ( 38 ) having. Bearing unit according to claim 11, characterized in that the separating edge ( 38 ) is arranged and configured such that in the second area ( 34 ) is deflected in the direction of the bearing row, while in the third area ( 36 ) and debris-enriched lubricant is deflected away from the bearing row. Bearing unit according to one of claims 1 to 7, characterized in that the channel ( 28 . 128 ) is designed such that the injected lubricant is atomized and a flow course ( 140a ; 240a ) of the atomized lubricant is generated in the direction of the bearing row, while lubricant particles enriched lubricant by a flow pattern ( 140b ; 240b ) is separated from the pure lubricant and directed away from the bearing row. Bearing unit according to one of claims 1 to 7 and 13, characterized in that the inner ring ( 12a , b; 112a ) in the first area substantially perpendicular to the shaft axis ( 18 ) the wave ( 16 ) running geometric contour ( 132 . 232 ) or a baffle plate ( 42 ) or an impingement edge on which the lubricant impinges and is thereby atomized. Bearing unit according to one of claims 1 to 6, characterized in that the channel ( 428 ) is designed in such a way or facilities ( 456 ; 458 )) which impart an angular momentum (swirl) to the injected lubricant, thereby separating lubricant-enriched lubricant from the pure lubricant due to centrifugal forces and is discharged while the pure lubricant is supplied to the bearing row. Bearing unit according to one of claims 1 to 15, characterized in that the channel ( 28 ; 128 ; 328 ; 428 ) is oriented such that the lubricant directly or indirectly on a ball cage ( 20 . 24 ; 120 ; 320 ; 324 ; 420 ) hits a bearing row and drives the ball cage in its direction of rotation. Bearing unit for a shaft ( 16 ) of a turbocharger having at least one outer ring ( 310 ), at least one inner ring ( 312a , b) and at least two bearing rows guided between outer ring and inner ring, wherein at least one channel ( 328 ) for injecting lubricant into a gap ( 314 ) is provided between the outer ring and the inner ring, characterized in that the channel ( 328 ) is oriented such that the lubricant directly or indirectly on a ball cage ( 320 ; 324 ) hits a bearing row. Bearing unit according to claim 17, characterized in that the ball cage ( 320 ; 324 ) Has baffles on which the lubricant impinges directly or indirectly. Bearing unit according to claim 17 or 18, characterized in that the ball cage ( 320 . 324 ) is formed asymmetrically in cross section. Bearing unit according to one of claims 17 to 19, characterized in that the cross section of the ball cage ( 320 . 324 ) comprises a longer leg and a shorter leg, which are arranged at an obtuse angle to each other, wherein the tip of the angle in the direction of the outer ring ( 310 ), and the longer leg in the direction of the channel ( 328 ) is arranged, through which the lubricant is introduced. Turbocharger having a turbine and a compressor, which are arranged on a common shaft, wherein the shaft is rotatably supported by means of a bearing unit according to claims 1 to 20.

Images