DE102006057810A1 - Driving wheel arrangement for ancillary unit of internal combustion engine, has driving wheel, which has running casing actively connected with attraction mechanism - Google Patents

Abstract

The driving wheel arrangement has a driving wheel (1), which has a running casing (2) actively connected with attraction mechanism. A hub (3) is connected in torque proof manner with the drive axle of an auxiliary unit. A damping device (4) is actively connected between the running casing and the hub, for preventing torsional vibrations. The damping device comprises a spring brake (5), which is effectively arranged between the running casing and the hub. The device makes an electrically conducting connection between the running casing and the hub.

Description

Field of the invention

The The invention relates to a drive wheel arrangement of an accessory train an internal combustion engine with a drive wheel, the one with a Traction means in actively connected running jacket, one with the drive axle an auxiliary rotatably connected hub and an intermediate the running jacket and the hub effectively arranged damping device for reducing torsional vibrations, wherein the damping device a spring accumulator, which between the running jacket and the Hub is arranged effectively.

Background of the invention

to Avoid unwanted torsional vibrations within one Auxiliary train of an internal combustion engine are drive wheel assemblies known with drive wheels of the type mentioned.

From the DE 42 25 304 A1 a disk-shaped component for a belt drive is known, in particular for driving an auxiliary unit of an internal combustion engine, which can be fastened on the crankshaft of the internal combustion engine. In this case, the disk-shaped component includes a damping device which is provided between an attachable to the crankshaft input part and a rotatable relative thereto output part, wherein the input and output part are rotatable relative to each other via a rolling bearing.

The DE 196 52 730 A1 discloses a provided for the arrangement on a crankshaft drive wheel of an accessory train whose damping device comprises a spring accumulator, a friction damper and a vibration damper.

The DE 10 2005 029 351 A1 shows a drive wheel for driving an accessory of an internal combustion engine of a vehicle with a damping device, wherein the drive wheel is coupled to a shaft and wherein the damping device comprises a non-lubricating torsional vibration damper.

Similar solutions are from the DE 102 16 082 A1 , from the DE 103 10 831 A1 and from the DE 602 00 178 T2 known.

adversely is in the previously known solutions that not always excluded it can be electrostatic charges of the drive wheel assembly comes in operation. This can be done in particular by the rotating belt be caused, which is often used as traction means becomes.

in the given case, d. H. if there are static charges in the Arrangement comes are functional impairments of electronic components to fear, for example, the engine electronics, the ABS system or the navigation aid is to call. thats why the requirement arose to make sure that under as possible no circumstances an electrostatic charge in the above said drive wheel arrangement can take place to problems with the Exclude electronics.

Further are partly also relatively high wear rates of the involved Components have been observed. In that regard, there is a desire, the components wear resistant in the least expensive way do.

When adversely, it has also been found that due to the often used for coming plastic in various parts of the drive wheel assembly and the associated poor heat conduction frequently a high thermal load of the components takes place.

Object of the invention

Of the The present invention is therefore based on the object, a drive wheel assembly of the aforementioned type so that reliable an electrostatic charge is prevented. Furthermore, should be achieved be that the arrangement wear as little as possible works, thereby increasing the life of the arrangement. Finally, the thermal load of the components be lowered.

Summary of the invention

The Solution of this problem by the invention is characterized by means of an electrically conductive connection between the Running jacket and the hub make.

For this Both the barrel and the hub can be at least partially, preferably completely, made of metal. Farther Both the barrel and the hub can at least partially, preferably completely, made of a plastic with a high fiber content exist, wherein the fibers are electrically conductive; come here As fibers in particular carbon fibers in question.

The means for producing an electrical connection may also comprise at least one disc of electrically conductive material which is fixed to the running jacket or to the hub and rubbing against the hub or on the running jacket or on a connected thereto or with this component. The component can be a disk be made of electrically conductive material. Again, it is preferably provided that the disc and the optional component at least partially, preferably completely, made of metal. Alternatively, these parts may at least partially, preferably completely, consist of a plastic with a high fiber content, wherein the fibers are electrically conductive, for. B. designed as carbon fibers.

The Means for producing an electrical connection can according to another embodiment of the invention also at least one radial extension made of electrically conductive material comprise, which is arranged on the running jacket or on the hub and frictionally starts at the hub or on the running jacket.

Further may be the means of making an electrical connection comprise a plain bearing bush of electrically conductive material, which is arranged between the running jacket and the hub. The plain bearing bush can be at least partially, preferably completely, Made of metal. You can also at least partially, preferably completely, made of a plastic with a high fiber content exist, wherein the fibers are electrically conductive, for. B. formed as carbon fibers. Alternatively, the means for Producing an electrical connection at least one ball bearing or rolling bearings of electrically conductive material, which is arranged between the barrel casing and the hub. In this Trap can be provided that the ball bearing or roller bearings Having means for power line between inner ring and outer ring, which are known as such.

After all may be the means of making an electrical connection a coating of electrically conductive material, the is applied to the barrel casing and / or on the hub. The coating made of electrically conductive material can be applied to the barrel jacket be, this being made of plastic. This makes the retention of plastic as a material for the running jacket possible.

The Coating is preferably according to the PVD method (Physical Vapor Deposition method) or the (PA) CVD method (Plasma Assisted Chemical Vapor Deposition method) applied.

The Thickness of the coating applied in this case is preferably maximum at 5 m, in particular at a maximum of 2 m.

The Coating can also be used as a solution to use, with a cylindrical inner surface the running jacket directly on a cylindrical outer surface the hub starts. In this case, the hub is preferably at least on its cylindrical outer surface a lubricious material.

Further can be provided that the drive wheel assembly continues at least a contacted by the traction means tensioning roller, which has a Running jacket and a hub, wherein means are provided, the an electrically conductive connection between the barrel casing and make the hub. The means of producing an electrical Compound may be a coating of electrically conductive material include, which applied to the barrel casing and / or on the hub is. The coating of electrically conductive material can on be applied to the barrel jacket, the barrel itself Plastic exists. Again, the preferred PVD method (Physical Vapor Deposition method) or the (PA) CVD method (Plasma Assisted Chemical Vapor Deposition method) for use. Again, the thickness of the coating is preferably maximum 5 m, in particular a maximum of 2 m.

The Means for producing an electrical connection can also at least one ball bearing or roller bearings made of electrical conductive material, which between the running jacket and the Hub of the tension roller is arranged. This can be the ball bearing or the rolling bearing means for power line between inner ring and outer ring.

Around to improve the heat flow, sees one for isolated measure or even a further development of Invention, that the frontal region of the drive wheel of the Drive wheel assembly is free of a cover.

The Damping device can be a serial arrangement of the spring accumulator and a slip clutch, wherein the spring accumulator between the running jacket and a rotatably mounted on the hub drive plate and the slip clutch between the drive plate and the hub are arranged effectively. Furthermore, the spring accumulator at least have a bow spring, in axially opposite one another semi-open annular chambers of the shell and the drive plate is guided and at their ends mutually each on a peripheral abutment surface of a driving cam of the running jacket and a driving cam of the drive plate is applied. The spring accumulator may have a plurality of spring elements, respectively circumferentially alternately between the barrel and the drive plate are arranged effectively.

With the invention proposal is especially on the barrel of the drive wheel, but also on other components of the arrangement, the electrical conductivity between the belt or the running jacket and the generator shaft, ie the hub, ensured. As a result, electrostatic charges are derived from the barrel casing and also prevents potential charges by a possibly occurring belt slippage on the barrel casing.

By the weiterbildungsgemäße coating of components The drive wheel assembly can also have a high wear resistance be achieved. This is especially true for the wear resistance of the running profile of the running mantle of drive wheel and tension pulley and in the event that there is contamination of the belt and the Running coats is coming.

The said coating also has the beneficial effect of having a higher heat conduction of the coated components can be achieved, so that the thermal insulation effect of is reduced to the use of coming plastic, causing the Heating of the components is lower. This also becomes advantageous Increase the life of the storage, since this is mostly is sensitive to high temperatures. The waiver of the invention supported on cover caps in the frontal region of the drive wheel this effect and can cause a noticeable drop in temperature to lead.

Yet can advantageously the per se favorable plastic construction of the parts in question.

Brief description of the figures

In The drawings are embodiments of the invention shown. Show it:

1 in exploded view, the drive wheel of a drive wheel assembly of an accessory train of an internal combustion engine,

2 the radial section through the drive wheel in the assembled state according to a first embodiment of the invention,

3 an enlarged section of the illustration 2 according to a second embodiment of the invention,

4 A third embodiment of the invention, wherein an enlarged part of the illustration 2 is shown

5 the detail "Z" according to 4 and

6 the radial section through a tension pulley of the drive wheel assembly.

Detailed description the figures

In 1 is a drive wheel 1 to see a Nebenaggregatezugs an internal combustion engine, the individual components in the exploded state, ie in an exploded view, are shown. Only the components of interest here are indicated. The drive wheel associated with an auxiliary unit, for example a generator 1 the ancillary train comprises a standing with a traction means, not shown, running jacket 2 , A non-rotatably connected to the drive axle of the auxiliary hub connected 3 and one between the running jacket 2 and the hub 3 effectively arranged damping device 4 for the reduction of torsional vibrations. The running coat 2 has on its outer circumference adapted to the traction means used contour, in the present case a V-ribbed belt is provided as traction means. The damping device 4 is from a serial arrangement of a spring store 5 and a slip clutch 20 educated. The spring store 5 has several bow springs 22 between the skirt 2 and one on the hub 3 rotatably mounted drive plate 21 are arranged, in axially opposite half-open annular chambers 23 . 24 of the running coat 2 and the drive disc 21 are guided, wherein these at their ends mutually on a peripheral stop surface of a driving cam 25 of the running coat 2 and a driving cam 26 the drive disc 21 issue. The slip clutch 20 is on the spring store 5 axially facing side between the drive plate 21 and the hub 3 arranged and has an annular disc-shaped friction ring which is between a friction surface of the drive plate 21 and a plate spring is arranged. Further details of this design are in the DE 10 2005 059 030 A1 described, which is hereby incorporated by reference.

In 2 is the drive wheel in radial section 1 to see according to a first embodiment of the invention. Here is the skirt 2 in the right area at the front with a disk 7 connected axially to a formed as a disk component 8th starts, which is connected to the hub. The running coat 2 and the hub 3 in the present case are made of metal, ie of electrically conductive material. Between running jacket 2 and hub 3 is a plain bearing bush 10 arranged, which is not necessarily made of electrically conductive material. Thus, optionally by the running of the belt, not shown, on the outer peripheral surface of the running jacket 2 produced electrostatic charge can flow, the present also made of metal discs 7 and 8th medium 6 for producing an electrically conductive connection. Ie. an electrostatic charge on the outer circumference of the barrel jacket 2 flows over the disk 7 and the disc 8th on the hub 3 so that there can be no disturbing effects as a result of charging.

Alternatively, all or at least a part of said components 2 . 3 . 7 . 8th Made of plastic, which can be made electrically conductive by the incorporation of electrically conductive fibers (or in another manner known per se) to achieve the desired effect, ie the dissipation of electrostatic charge from the barrel jacket 2 on the hub 3 ,

In the left frontal area 18 is a cover 19 plotted, which is provided in most embodiments. In order to facilitate the outflow of (friction) heat in a simple manner, is advantageous in 2 Cover still shown 19 not provided. It comes to a less obstructed heat flow from the heat source (storage in the middle of the drive wheel) to the frontal area 18 ,

An alternative realization of the means 6 for making an electrically conductive connection is in 3 shown. Here is the running jacket 2 a radial extension 9 on that extends so far radially inward until they reach the hub 3 reached. If the radial extension 9 axially on the hub 3 starts (as in 3 shown), can electrostatic charge from the barrel jacket 2 to the hub 3 drain, even if the plain bearing bushing 10 not made of electrically conductive material.

Another alternative embodiment of the invention concept goes from the 4 and 5 out. The running coat 2 consists here of (pure) plastic, so from non-conductive material. For a discharge of electrostatic charge from the belt profile of the running jacket 2 on the hub 3 To enable this, the procedure is as follows:
The running coat 2 here is completely covered with a thin layer of electrically conductive material. In 5 is shown that a coating 11 with a layer thickness d on the barrel jacket 2 was applied. The layer thickness is only a few m.

It is the applied coating 11 one produced by the PVD method (Physical Vapor Deposition) or the (PA) CVD method (Plasma Assisted Chemical Vapor Deposition).

at this method, the components are in a process chamber, in which by pumping a vacuum is generated. Leave in a vacuum very thin layers in a defined composition and reproducibly apply with specific properties.

These Procedure - which is well known and in use are - summarize the coating from the vapor phase, in which metals, alloys and chemical compounds by Supply of thermal or kinetic energy by means of particle bombardment be deposited in vacuo. The PVD process becomes physical passing the present materials into the gas phase, whereas in the (PA) CVD method, the layer components to be applied gas-bound, ie in a chemical state. With the PVD methods can be used to make thin layers of practical generate all elements. Chemical compounds, such as metal carbides, -nitrides or oxides, can be by supplying reactive gas also deposit and are for technical applications of great importance. With the CVD method can thin layers of many metals, non-metallic Elements, such as carbon or boron, as well as chemical compounds, such as borides, carbides, nitrides and oxides are deposited. The basis of the CVD process is a chemical reaction that associated with a high process temperature. When plasma assisted CVD methods make possible chemical reactions that in the thermodynamic equilibrium in the CVD process only at essential higher temperatures can occur, so that temperature-sensitive materials can be coated.

The coating 11 made of electrically conductive material, that is usually made of metal, surrounds the barrel jacket 2 on all sides. This has the advantage that it is not only made electrically conductive, but also has a high wear resistance. This also applies to its cylindrical inner surface 12 , which thus wear on the cylindrical outer surface 13 the hub 3 can start without providing a further plain bearing bush.

The explained principle can just as well be applied to other components of the drive wheel arrangement. In 6 is a tension roller 14 shown the strap over the running mantle 2 runs, spans. The tension roller 14 has a running coat 15 and a hub 16 , between which also an electrical conductivity is desired. The running coat 15 is by means of a ball bearing 17 on the hub 16 stored. Means for producing an electrical conductivity of a rolling or ball bearing between inner and outer ring are well known. Will the existing plastic skirt 15 provided in the manner explained above with an electrically conductive layer is also achieved in an advantageous manner that there is no electrostatic charging of the barrel jacket 15 can come.

If the coating is carried out in the manner mentioned with the PVA or with the (PA) CVD method In addition to the production of an electrical conductivity, there are further advantages:
Due to the small layer thickness of, for example, about 1 m, no relevant geometry deviation or influencing takes place. The applied layer adheres very well, ie there is no delamination and no abrasion. Also, the thermal conductivity at the component surface is improved.

As in 4 can be seen, if necessary, can be dispensed with a separate plain bearing bush, since the coated bore diameter itself acts as a sliding bearing element. Optionally, the hub with its cylindrical outer surface 13 be provided with lubricious plastic or consist of this.

With a view to 6 It can also be provided that a complete coating of a (ball) bearing including running jacket takes place. In this way, advantageously, a cost-effective complete coating can be made. Furthermore, a corrosion protection of the steel parts of the bearing is achieved on the outer surfaces. Furthermore, an improved wear protection of the steel parts of the bearing is achieved on its outer surfaces.

It So only the running surface of the running jacket can be coated be done, but also an all-round coating. Further Also, the (ball) bearing can be included in the coating. This applies to all conceivable configurations of the camp, z. B. single row, multi-row or designed as plain bearings.

1

Triebrad

2

Counterweight

3

hub

4

attenuator

5

spring

6

medium for producing an electrically conductive connection

7

disc

8th

component (Disc)

9

radial renewal

10

plain bearing bush

11

coating made of electrically conductive material

12

cylindrical palm

13

cylindrical outer surface

14

idler

15

Counterweight

16

hub

17

Bearings / Bearing

18

frontal Area

19

cover

20

slip clutch

21

driver disc

22

bow spring

23

annular chamber

24

annular chamber

25

drive cams

26

drive cams

d

thickness

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 4225304 A1 [0003]
• - DE 19652730 A1 [0004]
• - DE 102005029351 A1 [0005]
• DE 10216082 A1 [0006]
• DE 10310831 A1 [0006]
• - DE 60200178 T2 [0006]
• - DE 102005059030 A1 [0036]

Claims (33)

Drive wheel arrangement of an auxiliary train of an internal combustion engine with a drive wheel ( 1 ), which has a running jacket in operative connection with a traction device ( 2 ), a non-rotatably connected to the drive axle of an auxiliary hub ( 3 ) and one between the running jacket ( 2 ) and the hub ( 3 ) effectively arranged damping device ( 4 ) for reducing torsional vibrations, wherein the damping device ( 4 ) a spring store ( 5 ), which between the running jacket ( 2 ) and the hub ( 3 ), characterized by means ( 6 ), an electrically conductive connection between the running jacket ( 2 ) and the hub ( 3 ) produce. Drive wheel arrangement according to claim 1, characterized in that both the running jacket ( 2 ) as well as the hub ( 3 ) consist at least partially, preferably completely, of metal. Drive wheel arrangement according to claim 1, characterized in that both the running jacket ( 2 ) as well as the hub ( 3 ) at least partially, preferably completely, consist of a plastic with a high fiber content, wherein the fibers are electrically conductive. Drive wheel arrangement according to claim 3, characterized in that that the fibers are carbon fibers. Drive wheel arrangement according to claim 1, characterized in that the means ( 6 ) for making an electrical connection at least one disc ( 7 ) made of electrically conductive material, which on the running jacket ( 2 ) or at the hub ( 3 ) and rubbing on the hub ( 3 ) or on the running jacket ( 2 ) or on a component connected to it or to it ( 8th ) starts. Drive wheel arrangement according to claim 5, characterized in that the component ( 8th ) is a disc of electrically conductive material. Drive wheel arrangement according to claim 5, characterized in that the disc ( 7 ) and the optional component ( 8th ) consist at least partially, preferably completely, of metal. Drive wheel arrangement according to claim 5, characterized in that the disc ( 7 ) and the optional component ( 8th ) at least partially, preferably completely, consist of a plastic with a high fiber content, wherein the fibers are electrically conductive. Drive wheel arrangement according to claim 8, characterized in that that the fibers are carbon fibers. Drive wheel arrangement according to claim 1, characterized in that the means ( 6 ) for making an electrical connection at least one radial extension ( 9 ) made of electrically conductive material, which on the running jacket ( 2 ) or at the hub ( 3 ) is arranged and rubbing on the hub ( 3 ) or on the running jacket ( 2 ) starts. Drive wheel arrangement according to claim 1, characterized in that the means ( 6 ) for making an electrical connection a plain bearing bush ( 10 ) made of electrically conductive material between the running jacket ( 2 ) and the hub ( 3 ) is arranged. Drive wheel arrangement according to claim 11, characterized in that the plain bearing bush ( 10 ) consists at least partially, preferably completely, of metal. Drive wheel arrangement according to claim 11, characterized in that the plain bearing bush ( 10 ) at least partially, preferably completely, consist of a plastic with a high fiber content, wherein the fibers are electrically conductive. Drive wheel arrangement according to claim 13, characterized in that that the fibers are carbon fibers. Drive wheel arrangement according to claim 1, characterized in that the means ( 6 ) comprise at least one ball bearing or rolling bearing made of electrically conductive material, which between the running jacket ( 2 ) and the hub ( 3 ) is arranged. Drive wheel arrangement according to claim 15, characterized in that that the ball bearing or rolling bearing means for power line having between inner ring and outer ring. Drive wheel arrangement according to claim 1, characterized in that the means ( 6 ) for producing an electrical connection a coating ( 11 ) made of electrically conductive material which are applied to the barrel 2 ) and / or on the hub ( 3 ) is applied. Drive wheel arrangement according to claim 17, characterized in that the coating ( 11 ) made of electrically conductive material on the barrel casing ( 2 ) is applied, wherein the running jacket ( 2 ) consists of plastic. Drive wheel arrangement according to claim 17, characterized in that the coating ( 11 ) according to the PVD method (Physical Vapor Depositi on-process) or the (PA) CVD process (Plasma Assisted Chemical Vapor Deposition process) is applied. Drive wheel arrangement according to claim 17, characterized in that the thickness (d) of the coating ( 11 ) is at most 5 microns, preferably at most 2 microns. Drive wheel arrangement according to claim 17, characterized in that a cylindrical inner surface ( 12 ) of the running mantle ( 2 ) directly on a cylindrical outer surface ( 13 ) the hub ( 3 ) starts. Drive wheel arrangement according to claim 21, characterized in that the hub ( 3 ) at least on its cylindrical outer surface ( 13 ) consists of a lubricious material. Drive wheel arrangement according to claim 1, characterized in that it further comprises at least one tensioning roller ( 14 ), which has a running jacket ( 15 ) and a hub ( 16 ), where means ( 6 ) are provided, which provide an electrically conductive connection between the running jacket ( 15 ) and the hub ( 16 ) produce. Drive wheel arrangement according to claim 23, characterized in that the means ( 6 ) for producing an electrical connection a coating ( 11 ) made of electrically conductive material which are applied to the barrel 15 ) and / or on the hub ( 16 ) is applied. Drive wheel arrangement according to claim 24, characterized in that the coating ( 11 ) made of electrically conductive material on the barrel casing ( 15 ) is applied, wherein the running jacket ( 15 ) consists of plastic. Drive wheel arrangement according to claim 24, characterized in that the coating ( 11 ) is applied by the PVD method (Physical Vapor Deposition method) or the (PA) CVD method (Plasma Assisted Chemical Vapor Deposition method). Drive wheel arrangement according to claim 24, characterized in that the thickness (d) of the coating ( 11 ) is at most 5 microns, preferably at most 2 microns. Drive wheel arrangement according to claim 23, characterized in that the means ( 6 ) for producing an electrical connection at least one ball bearing ( 17 ) or rolling bearings of electrically conductive material, which between the running jacket ( 15 ) and the hub ( 16 ) is arranged. Drive wheel arrangement according to claim 28, characterized in that the ball bearing ( 17 ) or rolling bearing means for power line between inner ring and outer ring has. Drive wheel arrangement according to claim 1, characterized in that the frontal area ( 18 ) of the drive wheel ( 1 ) free from a cover ( 19 ). Drive wheel arrangement according to claim 1, characterized in that the damping device ( 4 ) a serial arrangement of the spring accumulator ( 5 ) and a slip clutch ( 20 ), wherein the spring accumulator ( 5 ) between the running jacket ( 2 ) and one on the hub ( 3 ) rotatably mounted drive plate ( 21 ) as well as the slip clutch ( 20 ) between the drive plate ( 21 ) and the hub ( 3 ) are arranged effectively. Drive wheel arrangement according to claim 31, characterized in that the spring accumulator ( 5 ) at least one bow spring ( 22 ), which in axially opposite half-open annular chambers ( 23 . 24 ) of the running mantle ( 2 ) and the drive plate ( 21 ) is guided and at their ends mutually on each of a peripheral abutment surface of a driving cam ( 25 ) of the running mantle ( 2 ) and a driving cam ( 26 ) of the drive plate ( 21 ) is present. Drive wheel arrangement according to claim 32, characterized in that the spring accumulator ( 5 ) a plurality of spring elements ( 22 ), each circumferentially alternately between the running jacket ( 2 ) and the drive plate ( 21 ) are arranged effectively.