Abstract:
A supercharger device, including, at least one of a variable turbine and a compressor geometry; a guide vane device arranged in a housing, wherein the guide vane device includes at least one vane mounting ring; at least one guide vane is at least one of rotatably mounted thereon the vane mounting ring and rotatably mounted therein the vane mounting ring; and an adjusting ring arranged coaxially to the vane mounting ring and mounted on the latter, which is rotated relative to the vane mounting ring.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application is a National Stage application which claims the benefit of International Application No. PCT/EP2008/065453 filed Nov. 13, 2008, which claims priority based on German Application No. 10 2007 056 154.9, filed Nov. 21, 2007, both of which are hereby incorporated by reference in their entirety. 
     TECHNICAL FIELD 
     The invention relates to a supercharger device, particularly an exhaust gas turbocharger for a motor vehicle. The invention additionally relates to a combustion engine for a motor vehicle equipped with such a supercharger device. 
     BACKGROUND 
     Exhaust gas turbochargers are usually employed to increase the performance of piston engines, wherein they increase an air and fuel throughput per work cycle. The exhaust gas turbocharger driven by the exhaust gas flow of the piston engine compresses the air fed to the combustion chamber, wherein, because of different engine operating states, it can be advantageous to decouple the compressed air flow fed to the combustion chamber from the exhaust gas flow, so that more preferably efficiency, response characteristics or operating range of the exhaust gas turbocharger can be improved. Such intervention for controlling the exhaust gas turbocharger can for example be achieved through a variable geometry of the nozzle ducts leading to the turbine wheel. 
     From DE 102 62 006 B4 an exhaust gas turbocharger with a variable turbine geometry is known, which is realised via a vane mounting ring with guide vanes rotatably mounted thereon/therein, wherein the guide vanes can be adjusted via an adjusting ring mounted coaxially to the vane mounting ring and rotatably with respect to the latter. Here, at least three roller bearings are rotatably mounted on the vane mounting ring, which in turn support the adjusting ring via a respective circumferential groove. Here, the roller bearings supporting the adjusting ring can be exclusively mounted in the vane mounting ring or additionally in a housing part, which improves the mounting but significantly aggravates the installation, that is the assembly. 
     A further charging device with a variable turbine geometry is known for example from EP 1 009 918 B1. 
     SUMMARY 
     The present invention deals with the problem of stating an improved embodiment for a generic supercharger device which is more preferably characterized by improved mounting of an adjusting ring. 
     According to the invention, this problem is solved through the subjects of the independent claims. Advantageous embodiments are the subject of the dependent claims. 
     The invention is based on the general idea of mounting an adjusting ring coupled with the guide vanes of a guide vane device via slide or roller bearings, wherein these slide or roller bearings are provided on a respective locating pin which penetrates a vane mounting ring carrying the guide vanes and defines its spacing from a housing or from an insert piece/cover disc element arranged therein. Here, the adjusting ring is arranged coaxially to the vane mounting ring and mounted on the latter via the mentioned roller or slide bearings. The adjustment of the guide vanes mounted on the vane mounting ring is brought about via a rotation of the adjusting ring relative to the vane mounting ring. Through the mounting of the adjusting ring on the vane mounting ring via slide or roller bearings, each of which is arranged on a locating pin penetrating the vane mounting ring, the mounting of the adjusting ring can be simplified and the part variety of the supercharger device according to the invention reduced, since the roller or the slide bearings now no longer need to be mounted on the vane mounting ring separately from the locating pins, but can be fixed on the vane mounting ring via the locating pins. Thus the locating pins fulfil two objectives simultaneously, namely defining an axial spacing between the vane mounting ring and a housing or an insert piece/cover disc element arranged in the latter and also acting as carrier for the slide or roller bearings. Because of this, the supercharger device can more preferably also be designed simpler, which contributes to keeping maintenance or repair expenditure low while lowering the manufacturing costs for the supercharger device according to the invention at the same time. In addition, the roller or slide bearings carried by the locating pins ensure particularly smooth-running mounting of the adjusting ring and thus particularly high mounting quality. The high mounting quality here is also responsible for high adjusting accuracy of the guide vane, as a result of which the supercharger device according to the invention can be adapted to the respective operating situation with particular accuracy. 
     With an advantageous further development of the solution according to the invention a roller bearing with a rotatably mounted bearing roller is provided on each locating pin. A bearing roller rotatably mounted in such a manner can also be produced simply and thus cost-effectively and additionally guarantees particularly smooth-running mounting of the adjusting ring. Here, the adjusting ring can be guided via a ring groove worked into the respective bearing roller in which the adjusting ring engages. With a further advantageous embodiment of the solution according to the invention at least one locating pin comprises a collar at its end carrying the roller bearing, which collar forms an axial stop for the bearing roller. A collar moulded on to the locating pin in such a manner can be produced simply and preferentially in a single common operation together with the locating pin, wherein the locating pin with its longitudinal end facing away from the collar has to be inserted through the vane mounting ring. Obviously, other axial stops for the bearing roller are also conceivable, more preferably clamping pins or lock nuts for example. 
     Practically at least one locating pin comprises a first radial step via which said locating pin supports itself on the vane mounting ring, wherein an axial spacing between the first radial step and the collar of the locating pin is greater than an axial extension of the roller bearing or the bearing roller so that the latter is arranged with play between the vane mounting ring and the collar of the locating pin. Via the according to the invention first radial stage an axial spacing or accurate position of the locating pin to the vane mounting ring can be predetermined, wherein, when the first radial step contacts the vane mounting ring, the axial spacing between the vane mounting ring and the collar of the locating pin remaining for the bearing roller is greater than the axial longitudinal extension of the bearing roller, so that the latter can always be mounted on the vane mounting ring via the locating pin in a smooth-running manner without jamming. A further measure for ensuring the mounting of the bearing roller without jamming is therefore not required, wherein the first radial step can be produced simply in terms of production and consequently does not burden the supercharger device with additional spacer elements which have to be produced separately for example. 
     Further important features and advantages of the invention are obtained from the subclaims, from the drawings and from the corresponding figure description by means of the drawings. 
     It is to be understood that the features mentioned above and still to be explained in the following can not only be used in the respective combination stated, but also in other combinations or by themselves, without leaving the scope of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       Preferred exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein same reference characters refer to same or similar or functionally same components. 
       Here it shows in each case schematically, 
         FIGS. 1 to 9  a supercharger device in each case with a roller or slide bearing arranged on a locating pin according to the invention for the mounting of an adjusting ring on the vane mounting ring. 
     
    
    
     According to  FIG. 1  a supercharger device  1  merely shown partially, which for example can be designed as exhaust gas turbocharger for a motor vehicle, comprises a guide vane device  2 , with which a variable turbine and/or compressor geometry can be realised. Here, the guide vane device  2  comprises at least one vane mounting ring  3  with guide vanes  4  rotatably mounted thereon/therein and an adjusting ring  5  arranged coaxially to the vane mounting ring  3 , via which the guide vanes  4  can be jointly adjusted. As can be seen from  FIG. 1 , the guide vanes  4  are rotatably mounted on the vane mounting ring  3  by means of vane pins  6 , wherein the vane pins  6  axially penetrate the vane mounting ring  3  and are each connected in a rotationally fixed manner with the guide vane  4  on the one end and with a vane lever  7  on the other end, each of which carries a lever head  8  directed radially to the outside and thus engages in a corresponding clearance on the adjusting ring  5  which is not shown. A rotary movement of the adjusting ring  5  with respect to the vane mounting ring  3  thus brings about an even rotational movement of all guide vanes  4  about their vane pins  6 . 
     DETAILED DESCRIPTION 
     In order to render mounting of the adjusting ring  5  rotatably designed with respect to the vane mounting ring  3  as simple as possible constructionally it is provided according to the invention that mounting of the adjusting ring  5  takes place on the vane mounting ring  3  via slide or roller bearings, each of which is arranged on a locating pin penetrating the vane mounting ring  3 . The locating pin  9  simultaneously serves to define an axial spacing of the vane mounting ring  3  from a housing or from an insert piece/cover disc element  10  arranged therein. As is more preferably evident in  FIG. 1  there is a radial gap between the locating pin  9  and the vane mounting ring  3 , as a result of which an at least certain radial and axial displaceability of the vane mounting ring  3  with respect to the housing  10  is established. This displaceability makes it possible to better offset elongations and/or tolerances and reduces at least the danger of jamming the guide vanes  4 . 
     According to  FIG. 1 , the roller bearing comprises a rotatably mounted bearing roller  11 , which in axial direction is arranged adjacent to the vane mounting ring  3  on the one hand and to an axial stop  12 , for example a nut, on the other end. The spacing between the vane mounting ring on the one end and the housing  10  on the other end is limited by two radial steps, namely a second radial step  13  and a third radial step  14  in the case of the embodiment according to  FIG. 1 . By way of the second radial step  13  the locating pin  9  supports itself on the insert piece/cover disc element  10 , while it supports itself on the vane mounting ring  3  via the third radial step  14 . Such radial steps  13 ,  14  can be produced in a particularly simple manner for example through a turning operation and thus do away with a spacer sleeve  15  to be provided in this region, as is proposed for example in  FIGS. 5 ,  6 ,  8  and  9 . 
     In order to be able to also fix the axial stop  12  with defined axial spacing from the vane mounting ring  3  an additional, namely a fourth radial step  16  can be provided, which in the assembled state is abutted by the axial stop  12 . Here, the bearing roller  11  is mounted on the locating pin  9  in a smooth-running manner according to  FIG. 1 , wherein the axial spacing predetermined by the radial steps  14  and  16  between the axial stop  12  and the vane mounting ring  3  is greater than the axial longitudinal extension of the bearing roller  11 , so that the latter can always be mounted without jamming. The same also applies to the guide vanes  4  since the axial spacing between the housing  10  and the vane mounting ring  3 , which is limited by the second and third radial step  13 ,  14 , reliably prevents jamming of the guide vanes  4  between the vane mounting ring  3  and the insert piece/cover disc element  10 . 
     Instead of the axial stop  12  shown according to  FIG. 1  the locating pin  9  at its end carrying the bearing roller  11  can also comprise a collar  17 , as is shown for example in  FIGS. 6 and 9 . This collar  17  forms another embodiment for an axial stop  12 . A further possibility for an axial stop  12  is formed by a bearing sleeve  18  comprising a collar, as is shown for example in accordance with  FIG. 2 . Here, the bearing sleeve  18  is arranged between the locating pin  9  and the associated roller bearing, i.e. the bearing roller  11 , wherein the bearing sleeve  18  has a greater axial extension than the bearing roller  11 , so that the latter is arranged with play between the vane mounting ring  3  and the collar of the bearing sleeve  18 . Here, the bearing rollers  11  shown in accordance with  FIGS. 1 to 7  and  9  can also be designed as slide bearings, so that these are not rotatably mounted with respect to the locating pin  9 , but the adjusting ring  5  is mounted, more preferably guided in a circumferential groove  19  of the bearing roller  11  designed as slide bearing. 
     According to  FIGS. 4 and 5  the locating pin  9  is designed without radial steps, which is why in this case, for the reliable definition of the axial spacing between the vane mounting ring  3  on the one end and the insert piece/cover disc element  10  on the other end, the locating pin  9  is permanently joined, more preferably pressed together both with the insert piece/cover disc element  10  as well as with the vane mounting ring  3 . The bearing roller  11  can also be designed as slide bearing with these embodiments. 
     Considering the embodiment according to  FIG. 6 , it is evident that the locating pin  9  comprises a first radial step  20  via which it supports itself on the vane mounting ring  3  and wherein an axial spacing between the first radial step  20  and the collar  17  of the locating pin  9  is greater than the axial extension of the bearing roller  11 , so that the latter can be arranged with play between the vane mounting ring  3  and the collar  17  of the locating pin  9 . Mounting of the bearing roller  11  free of jamming is also established in this case. 
     In contrast with  FIG. 6 , wherein the spacer sleeve  15  lies on the insert piece/cover disc element  10  on the face end or the vane mounting ring  3 , the spacer sleeves  15  according to  FIGS. 8 and 9  are each inserted in the vane mounting ring  3  on the one end and in the housing  10  on the other end. Because of this it is possible to thermally decouple the locating pin  9  from the hot exhaust gases flowing about the guide vanes  4 , as a result of which the locating pin  9  is altogether arranged in a protected manner. 
     Preferentially, fastening of the locating pin  9  to the insert piece/cover disc element  10  or on the housing is provided by means of rivets, screws or welding with all supercharger devices  1  shown.  FIGS. 1-4  and  7  show the locating pin  9  for example in the non-riveted state. In  FIGS. 5 and 8  and  9  the locating pin  9  can also be screwed into the insert piece/cover disc element  10 . 
     According to  FIG. 8 , a bearing head  21  with a circumferential groove  19  is provided on an end of the locating pin  9  facing the adjusting ring  5 , in which the adjusting ring  5  is guided in a sliding manner. Reliable mounting of the adjusting ring  5  on the vane mounting ring  3  generally requires that at least three bearing rollers  11  or three bearing heads  21  with an angular region of 120° each are provided between two bearing rollers  11 /bearing heads  21 . Obviously it is also conceivable that four or more bearing rollers  11  are provided. 
     Through the supercharger device according to the invention particularly simple and highly functional mounting of the adjusting ring  5  on the vane mounting ring  3  can be realised, since the locating pins  9 , which define an axial spacing between the vane mounting ring  3  and the insert piece/cover disc element  10 , simultaneously function as carriers for the bearing rollers  11  or bearing heads  21  supporting the adjusting ring  5 . Because of this a reduction of the parts variety is additionally achieved, as a result of which storage and logistics costs can also be reduced.