DE102015215356A1 - Variable turbine / compressor geometry - Google Patents

Abstract

The invention relates to a variable turbine / compressor geometry (1), in particular for an exhaust gas turbocharger of a motor vehicle, comprising - a blade bearing ring (2) with a plurality of through holes, - an equivalent to the through holes of the blade bearing ring (3) number of guide vanes (4) each with a vane pivot (5) are rotatably mounted in an associated passage opening of the vane bearing ring (3), wherein on one of the guide vane (4) facing away from the end of the vane pin (5) an adjusting lever (6) is rotatably connected, - with respect to the vane ring ( 3) rotatable adjusting ring (7) which is operatively connected to the adjusting levers (6) and - an adjusting device (8) for limiting a through the variable turbine / compressor geometry (1) flowing minimum gas flow. It is essential to the invention that the adjusting device (8) is designed as a ring (9) connected fixedly to the blade bearing ring (3) with at least one elevation (10), the at least one elevation (10) forming a minflow stop for an associated adjusting lever (10). 6) and thus forms a minflow stop for the guide vanes (4).

Description

The present invention relates to a variable turbine / compressor geometry, in particular for an exhaust gas turbocharger of a motor vehicle, according to the preamble of claim 1. The invention also relates to a charging device, in particular an exhaust gas turbocharger, with such a variable turbine / compressor geometry.

From the DE 10 2008 053170 A1 is a generic variable turbine / compressor geometry, in particular for an exhaust gas turbocharger of a motor vehicle known.

A variable adjuster positioned in a charger housing allows adjustment of at least a minimum volume flow in the low speed range of an engine by rotating the variable adjuster. Since the variable adjustment after the final assembly from the outside is no longer accessible and also improved tamper resistance and proof of subsequent manipulation of the variable turbine / compressor geometry is to be facilitated, a Minflow stop was previously attached externally.

From the WO 2011/146555 A2 as well as from the WO 2014/081602 A1 Further generic variable turbine / compressor geometries are known.

Usually charging devices and in particular exhaust gas turbocharger are equipped with an electric or pneumatic actuator, which is required for the adjustment of an adjustment of the variable turbine / compressor geometry. The actuator is controlled via the motor control and moves a control rod, which acts on an actuator lever, which converts the linear movement of the control rod in a rotational movement. The rotation of the actuator lever is transmitted by the adjusting shaft to the adjusting device. This kinematics ensures the regulation of the mass flow flowing through the variable turbine / compressor geometry.

A disadvantage of variable turbine / compressor geometries known from the prior art, however, is that due to the sum of tolerances, a minimum mass flow (Minflow) can not be specified as a "hard" stop, but must be set. Nevertheless, a very precisely performed at the beginning setting a Minflow stop position due to wear and vibration occurring during operation can cause the variable turbine / compressor geometry can not be operated over the entire term with a constant minimum mass flow (Minflow).

The present invention therefore deals with the problem of providing for a generic variable turbine / compressor geometry, an improved or at least one alternative embodiment, which allows comparatively easy to set a minimum mass flow (Minflow) exactly and over the entire life of the variable turbine / Maintain compressor geometry.

This problem is solved according to the invention by the subject matter of independent claim 1. Advantageous embodiments are the subject of the dependent claims.

The present invention is based on the general idea of keeping a tolerance chain when setting a minflow position of a variable turbine / compressor geometry extremely short by providing a minflow stop directly on a blade bearing ring of the variable turbine / compressor geometry, so that all, for example previously lying tolerances, caused for example by the control rod and an actuator lever, can already be eliminated. In the case of the variable turbine / compressor geometry according to the invention, the minflow stop is thus located almost directly on the guide vanes, so that all disturbing influences occurring, for example, outside a charging device are irrelevant to the minflow stop. The variable turbine / compressor geometry according to the invention has in a known manner a blade bearing ring with a plurality of passage openings and an equivalent to the through holes of the blade bearing ring number of vanes, which are each rotatably mounted with a blade bearing journal in an associated passage opening of the blade bearing ring. At one of the guide vane end facing away from the vane bearing journal while an adjusting lever is connected rotatably. Furthermore, provision is made for an adjusting ring which can be rotated relative to the blade bearing ring and which is operatively connected to the adjusting levers and capable of simultaneously displacing all the guide vanes. By means of an adjustment device, a minimal gas flow flowing through the variable turbine / compressor geometry is thereby limited. According to the invention, this adjusting device is then designed as a ring permanently connected to the blade bearing ring with at least one elevation, wherein the at least one elevation forms the minflow stop for an associated adjusting lever and thus a minflow stop for all the stator blades. The ring according to the invention can be connected in almost any way firmly with the blade bearing ring, for example, welded, clamped, soldered or pressed, and thereby forms a directly interacting with a lever Minflow stop, which is an adjustment of the at least one adjustment over thus limited over the adjusting all adjustment lever and thus provides a direct stop without an intermediate, long tolerance chain available. This offers particular advantages compared to the prior art, in which, for example, a minflow stop is provided outside the charging device, in particular at a pressure cell. In this case, however, a control rod, a connection to the actuator lever, the actuator lever itself, as well as a connection of the actuator lever with the variable turbine / compressor geometry, is a chain of tolerances which is not necessarily easy to control and which can be reliably and over the entire life of the variable turbine / Compressor geometry makes fixed fixing of the Minflow stop almost impossible. In contrast, in the variable turbine / compressor geometry according to the invention, this tolerance chain is completely eliminated since the minflow stop is placed directly on the variable turbine / compressor geometry inside the charging device.

In an advantageous development of the solution according to the invention, the ring has at least two elongated holes extending in the circumferential direction, through which a fixing element is guided in each case. Such a fixing element may for example be a screw or a notched nail, which initially allows a precise setting of the minflow stop of the individual guide vanes and then by fixing the at least two fixing elements firmly connects the ring with the blade bearing ring and thus fixes the long-stroke minflow stop , This allows the setting and fixing of the Minflow stop simple, inexpensive, but still reliable.

In a further advantageous embodiment of the solution according to the invention, the ring is formed as Umformblechteil. Such a forming part, in particular an unshaped sheet metal part, thus represents a particularly cost-effective way of producing the ring and thus the adjusting means. Alternatively, of course, the ring may also be formed as a metal powder injection molded part and in particular manufactured in the MIM process. In powder injection molding, metal powder provided with a binder is processed in an injection molding process, and the binder is subsequently removed. This makes it possible to produce complex parts in large quantities with extremely low tolerances and at the same time cost. The removal of the binder is usually accomplished via a childbirth, for example, a sintering.

In a further advantageous embodiment of the solution according to the invention, at least one surface of the ring is nitrided. In the case of nitriding, also referred to as embossing, a surface of a component formed from metal, in particular a component formed from steel, is hardened. In this case, the ring is thus made of steel and nitrided to increase its surface quality, in particular in the region of the elevations. Purely theoretically, of course, boriding is also conceivable, which is a thermochemical surface hardening for producing a wear-resistant surface on a workpiece. This method is based on the introduction of boron into the edge zone of a material at a temperature between 850 and 950 ° C.

In a further advantageous embodiment of the solution according to the invention, the ring is formed in one piece or in several parts. In particular, the one-piece embodiment enables a simple and therefore cost-effective installation on the variable turbine / compressor geometry, whereby the manufacturing cost of a equipped with such a variable turbine / compressor geometry charging device can be reduced. Of course, a multi-part embodiment is conceivable in which the individual components are additionally fixed to the ring with each other, in particular joined, and then attached to the blade bearing ring of the variable turbine / compressor geometry.

The present invention is further based on the general idea to provide a charging device, in particular an exhaust gas turbocharger, with a previously described variable turbine / compressor geometry, whereby a Minflow stop long term, that is, preferably over the entire life tolerance and reliably can be ensured, which in particular a same over the lifetime of the charging device and optimal response allows. As a result, it is possible to influence the performance of an internal combustion engine equipped with such a charging device in a particularly positive manner.

Other important features and advantages of the invention will become apparent from the dependent claims, from the drawings and from the associated figure description with reference to the drawings.

It is understood that the features mentioned above and those yet to be explained below can be used not only in the particular combination given, but also in other combinations or in isolation, without departing from the scope of the present invention.

Preferred embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description, wherein like reference numerals refer to the same or similar or functionally identical components.

Show, each schematically

1 a variable turbine / compressor geometry according to the invention in a minflow position,

2 a representation like in 1 but from the back,

3 a representation like in 1 but in a maxflow position,

4 a representation of 3 from a back,

5 an adjusting device according to the invention designed as a ring,

6 a representation like in 3 , but with additionally arranged on the ring guide rollers,

7 a view of one according to the 6 illustrated ring,

8th a representation like in 7 , with open ring.

According to the 1 to 4 . 6 , Has a variable turbine / compressor geometry according to the invention 1 , in particular for a charging device 2 For example, an exhaust gas turbocharger for a motor vehicle, a blade bearing ring 3 and rotatably mounted vanes therein 4 on, each with a shovel journal 5 in an associated passage opening of the blade bearing ring 2 are rotatably mounted. On one of the vane 4 remote end of the vane bearing journal 5 is in each case an adjusting lever 6 rotatably connected. For simultaneous adjustment of the individual vanes 4 is an adjusting ring 7 provided with the individual adjusting levers 6 is effective. To limit a minimum flow through the variable turbine / compressor geometry 1 is an adjustment device 8th provided according to the invention as fixed to the blade bearing ring 3 connected ring 9 is formed and at least one survey 10 , preferably even one of the number of lever 6 equivalent number of surveys 10 , having. By directly with the blade bearing ring 3 on the one hand and with the adjustment levers 6 about the surveys 10 on the other hand contact-effective adjustment 8th a tolerance chain can be kept extremely low, in particular compared to known from the prior art external Minflow attacks, for example in a pressure cell, whereby the Minflow long-term, preferably even over the entire life of the variable turbine / compressor geometry reliably and accurately adjusted can. Looking at the ring 9 , it can be seen that this at least two circumferentially extending slots 11 (compare also the 5 such as 7 and 8th ), through which in each case a fixing element 12 , For example, a notched nail, a rivet or a screw is guided.

Setting the Minflow stop the invention as a ring 9 trained adjusting device 8th takes place as follows:
First, the ring 9 over the fixing elements 12 rotatable relative to the blade bearing ring 3 stored on this and then the variable turbine / compressor geometry 1 fully assembled. Now a position is set for a minflow position where a minimum gas flow through the variable turbine / compressor geometry 1 should flow. If this minflow position is set, the ring becomes 9 such relative to the vane ring 3 twisted until the individual surveys 10 of the ring 10 on the associated adjusting lever 6 issue. Subsequently, the fixing elements 12 fixed and thereby the ring 9 relative to the vane ring 3 fixed against rotation. Additionally or alternatively, of course, another fixation, for example by pressing, welding, soldering or jamming of the ring 9 at the vane bearing ring 3 respectively. By now on the blade bearing ring 3 fixed ring 9 the Minflow stop is specified for the entire lifetime of the variable turbine / compressor geometry 1 , Due to the direct contact of the adjustment 8th about their surveys 10 at the individual adjusting levers 6 can also be created an extremely short tolerance chain, resulting in even under adverse operating conditions of the Minflow stop and thus the Minflow flow through the variable turbine / compressor geometry 1 should not change. As a result, in particular a response of one with such a variable turbine / compressor geometry 1 equipped charging device 2 guaranteed in the long term.

The ring 9 may be formed, for example, as a formed part, in particular as a sheet-metal forming part, or alternatively as a metal powder injection molded part, whereby likewise a high-quality embodiment with low unit costs can be achieved.

To the wear resistance of the ring according to the invention 9 To be able to increase, can also be provided that the ring 9 is formed of steel and whose surface is nitrated or borated. Of course, other materials or other methods for surface treatment come into consideration.

In the illustrated embodiments of the ring 8th according to the 1 to 5 , this is one-piece, in particular even integrally formed while he according to the 6 to 8th formed in several parts and additionally guide rollers 13 for radial guidance of the adjusting ring 7 having. These leadership roles 13 can rotatably or rotatably on the ring 9 be arranged. In a rotatable arrangement of the adjusting ring 7 roller bearing, while he in a non-rotatable arrangement of the guide rollers 13 on the ring 9 is slidably mounted.

Looking at the ring 9 according to the 8th , so you can see that this is designed as an open ring, causing the ring 9 can be compressed and, for example, radially auffedern, creating a radial clearance for adjusting 7 varies and in particular can be adjusted. After setting the desired radial clearance to the adjusting ring 7 will of course be the open ring 9 at the vane bearing ring 3 fixed.

With the inventive variable turbine / compressor geometry 1 For example, a tolerance chain previously existing for a minflow stop can be completely eliminated and thus a minflow over the entire life of the variable turbine / compressor geometry 1 be set exactly and unchangeable. This is achieved by the direct connection of the Minflow stop by the surveys 10 of the ring 9 at the vane bearing ring 3 , In addition, this significantly improved since reduced tolerance setting of the Minflow stop can be realized inexpensively.

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 102008053170 A1 [0002]
• WO 2011/146555 A2 [0004]
• WO 2014/081602 A1 [0004]

Claims (10)

Variable turbine / compressor geometry ( 1 ), in particular for an exhaust gas turbocharger of a motor vehicle, comprising - a blade bearing ring ( 2 ) with a plurality of through openings, - one to the through holes of the blade bearing ring ( 3 ) equivalent number of vanes ( 4 ), each with a vane journal ( 5 ) in an associated passage opening of the blade bearing ring ( 3 ) are rotatably mounted, wherein on one of the guide vane ( 4 ) facing away from the end of the vane journal ( 5 ) an adjusting lever ( 6 ) is connected rotationally fixed, - with respect to the blade bearing ring ( 3 ) rotatable adjusting ring ( 7 ), with the adjusting levers ( 6 ) and - an adjustment device ( 8th ) for limiting one by the variable turbine / compressor geometry ( 1 ) flowing minimum gas stream, characterized in that the adjusting device ( 8th ) as fixed to the blade bearing ring ( 3 ) connected ring ( 9 ) with at least one survey ( 10 ), wherein the at least one survey ( 10 ) a Minflow stop for an associated adjusting lever ( 6 ) and thus a minflow stop for the guide vanes ( 4 ). Variable turbine / compressor geometry according to claim 1, characterized in that the ring ( 9 ) at least two circumferentially extending oblong holes ( 11 ), by each of which a fixing element ( 12 ) is guided. Variable turbine / compressor geometry according to claim 1 or 2, characterized in that the ring ( 9 ) with the blade bearing ring ( 3 ) is pressed, welded, soldered or clamped. Variable turbine / compressor geometry according to one of the preceding claims, characterized in that the ring ( 9 ) is formed as a formed part, in particular as a sheet metal forming part. Variable turbine / compressor geometry according to one of claims 1 to 3, characterized in that the ring ( 9 ) is designed as a metal powder injection molded part. Variable turbine / compressor geometry according to one of claims 1 to 3, characterized in that the ring ( 9 ) formed of steel and at least one surface of the ring ( 9 ) is nitrated. Variable turbine / compressor geometry according to one of the preceding claims, characterized in that the ring ( 9 ) is formed in one piece or in several parts. Variable turbine / compressor geometry according to one of the preceding claims, characterized in that on the ring ( 9 ) Guide rollers ( 13 ) for guiding the adjusting ring ( 7 ) are arranged. Variable turbine / compressor geometry according to one of the preceding claims, characterized in that the ring ( 9 ) is designed as a closed ring or as an open ring. Charging device ( 2 ) with a variable turbine / compressor geometry ( 1 ) according to any one of the preceding claims.

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