WO2008155400A1

WO2008155400A1 - Drive for a prerotation guide device

Info

Publication number: WO2008155400A1
Application number: PCT/EP2008/057839
Authority: WO
Inventors: Josef Bättig; Mathias Richner
Original assignee: Abb Turbo Systems Ag
Priority date: 2007-06-20
Filing date: 2008-06-20
Publication date: 2008-12-24
Also published as: EP2006494A1

Abstract

According to the invention, the threaded spindle (52) engages in a spindle groove (53) that is secured to an element (54) that can be displaced in a translatory manner. The element is pushed into the desired position by rotating the spindle. The adjusting ring (30) is driven by means of a sliding piston (41) having milled grooves that are arranged in parallel and that are rotationally arranged in both fish plates (33) of the groove ring.

Description

Drive for pre-rotating guide

DESCRIPTION

Technical area

The invention relates to the field of turbomachines subjected to exhaust gases of internal combustion engines.

It relates to a drive for a guide device for generating a Vordralls in the intake of a compressor and an exhaust gas turbocharger with such a Vordrall guide.

PRIOR ART Exhaust gas turbochargers are used to increase the performance of internal combustion engines (reciprocating piston engines). In modern internal combustion engines, the adaptation of the exhaust gas turbocharger to variable operating conditions will become more difficult. A widely used option is the so-called variable turbine and / or compressor geometry. In the variable turbine geometry, the stator vanes are aligned more or less steeply with the flow upstream of the turbine wheel in accordance with turbine power requirements. In the variable compressor geometry, the vanes in the diffuser downstream of the compressor wheel are aligned more or less steeply to the flow.

Another way to adapt the exhaust gas turbocharger to the variable operating conditions offer Vordrall guide devices, which produce a certain Vordrall in the Luftansaugebereich the compressor in the intake air, depending on the operating point more or less pronounced mit- or opposite to the direction of rotation of the compressor wheel.

Such Vordrall guide devices, for example from DE 36 13 857 A1, or the European patent application of 31 March 2006 with the application number

06405137.8, the contents of which are incorporated herein by reference. These pre-whirl baffles include a plurality of vanes aligned radially with respect to the compressor axis. Each of the guide vanes comprises in addition to the projecting into the flow channel blade profi I a blade shank with which the blade profile is rotatably mounted in a housing. The blade profi I can be rotated about the axis of the blade shank via an adjusting lever. To drive the adjusting lever, and thus for adjusting the blade profile, an adjusting ring is provided, which is arranged concentrically to the axis of the compressor. By turning the adjusting ring, all blades are adjusted simultaneously about the respective axes of their blade shafts, whereby the flow guided to the compressor wheel with a positive or counter-rotating (with respect to the direction of rotation of the compressor wheel) is applied. The drive of the adjusting ring takes place in conventional pre-whirling Leitvorrichtungen then by an actuator outside the housing. This separate attachment of an actuator outside the housing requires a relatively large amount of space and usually additional auxiliary support for the support of the drive.

Brief description of the invention

The present invention enables an extremely compact, robust and reliably sealed integration of a pilot wheel drive.

As an optional actuator, a linear actuator, for example a stepper motor with threaded spindle, is used. This actuator is relatively inexpensive and very compact. In addition, it is quite robust in terms of vibration and temperature loads.

According to the invention, the threaded spindle engages in a spindle nut, which is fastened to a translationally displaceable element (dip tube). Turning the spindle moves the element to the desired position. The drive of the adjusting ring via a sliding pin with parallel milled which rotatably mounted in the two tabs of the U-ring. The coupling of the sliding pin via a parallel-walled groove in the dip tube. In order to allow a perfect seal a dip tube is used with a blind hole which is sealed with a piston sealing ring. This will ensure that no leakage can escape from the compressor housing. This is particularly important for premixed gas engines.

The use of a sliding pin / groove connection instead of a Schwenklaschen- connection valuable axial space can be obtained. By the lateral displacement of the groove within the axial Aussteckung the dip tube blind hole is an additional saving in the axial length.

Brief description of the drawings

Hereinafter, an embodiment of the invention will be explained in detail with reference to drawings. 1 shows an isometric view of a pre-whirl guide device arranged in the compressor housing,

FIG. 2 is an isometric detailed view of the drive of the pre-whirling guide apparatus of FIG. 1; FIG.

Fig. 3 shows the individual components of the drive of the pre-whirling guide device according to Fig. 2, and

4 shows a section perpendicular to the compressor axis by the drive of the pre-whirling guide device according to FIG. 2.

Way to carry out the invention

Fig. 1 shows a pre-whirling guide in the intake of a compressor. Such compressors are, as described above, used in exhaust gas turbochargers to increase the performance of internal combustion engines. The compressor comprises a compressor housing, which comprises the compressor wheel and forms the flow channel of the medium to be compressed. The radially outer housing 13 comprises in the illustrated embodiment, a housing extension 14 and a cover 15 for covering the arranged in the housing extension drive for the pre-whirling guide.

The guide device comprises a plurality of guide vanes 20 aligned in the radial direction with respect to the compressor axis. The guide vanes are in one inner housing 10 rotatably mounted. In the central region of the guide device, in which the tips of the plurality of guide vanes come together, a central housing body 12 is arranged. This central body is concentric with the axis of the compressor. The central body is part of the inner housing, which forms the flow channel of the medium to be compressed in the region of the guide device.

As shown, the central body 12 can be positioned and retained via one or more radially extending retaining ribs 11. In order not to affect the flow in the flow channel with such ribs, the central body can also be positioned and held on the vane tips. Fig. 2 allows a view into the interior of the outer housing, in particular to the inventive drive for the pre-whirl guide device and Fig. 3 shows in detail the individual components of the drive in disassembled state. Each of the guide vanes of the guide device comprises in addition to the projecting into the flow channel blade profi I 21 a blade shank 22, with which the blade profile is rotatably mounted in the housing, not shown. About an adjusting lever 23, the blade profile can rotate about the axis of the blade shank. For driving the adjusting lever, and thus for adjusting the blade profile, an adjusting ring 30 is provided, which is arranged concentrically to the axis of the compressor. In the illustrated embodiment, the torque is transmitted from

Adjusting ring 30 on the blade shank 22 via a arranged at the free end of the adjusting lever 23 ball 24. The ball head 24 is guided in a groove 31 of the adjusting ring with two parallel walls. In the groove of the ball head has the translational and rotational freedom of movement, which are necessary to implement the torque transfer. The ball head is arranged in a translationally displaceable sliding shoe 25. If the adjusting ring 30 is rotated for adjusting the guide vanes, the sliding shoe 25 is displaced by the ball head 24 in the groove 31 in the plane of the groove walls. If the adjusting ring is turned away, the position of the adjusting lever changes relative to the adjusting ring. In addition to the translational displacement of the center of rotation of the ball head within the groove, there is a rotation of the adjusting lever with respect to the adjusting ring. The translational displacement of the center of rotation of the ball head is made possible by the, along the groove walls sliding sliding shoe, while for the Rotation of the ball head in the molded by the shoe shoe ball cup can rotate in any direction as desired. The shoe may also be formed in two parts by a ball socket half is arranged with a flat, sliding back on each side of the groove in the adjusting ring. Alternatively, the torque transmission from the adjusting ring to the blade shank can also take place via a cylindrical pin arranged at the free end of the adjusting lever. The pin engages in a bore of an adjusting ring also mounted in a bore, cylindrical sliding element. The sliding cylinder can be rotated in the bore around its own axis and moved along its own axis. The bore in the sliding cylinder, which is provided for receiving the pin, is perpendicular to the axis of the sliding cylinder. The pin can be rotated in this hole around its own axis and move along its own axis. Thus, in turn, the necessary for the implementation of torque transfer freedom of movement, two translational and rotational, given. Optionally, the pin can be fixed in the sliding cylinder and mounted for sliding in a corresponding hole in the free end of the adjusting lever of the guide vane.

Instead of the illustrated and described in detail further embodiments for torque transmission are conceivable, for example with a trained as a gear segment adjusting lever, which engages in the provided with a ring gear adjusting ring. Blade profile 21, blade shank 22 and the adjusting lever 23 together with the necessary for torque transfer essay can be formed one or more parts. For rotating the adjusting ring 30, an actuator device 50 according to the invention is provided which, in addition to the actuator 51, ie the actual drive, comprises at least one movable element running tangentially to the adjusting ring 30, which is connected to the adjusting ring via a coupling. Several design options are provided.

In the illustrated embodiment, the actuator 51 drives a rotatable threaded spindle 52 which rotates but does not translate. The threaded spindle is a cylindrical round rod, on which a trapezoidal or flat thread is applied. Also conceivable are arcuate grooves for receiving a recirculating ball nut. The actuator is optionally designed as an electric stepper motor, in which via the control terminal 57, the desired direction of rotation can be adjusted. The actuator 51 is fastened with fastening means 58 on the housing in the region of the housing extension 14. The spindle 52 extends in the tangential direction to the adjusting ring. The immersion tube is, as can be seen in the section of FIG. 4, guided in a housing bore 16 in the housing extension 14 and has a central longitudinal bore on the spindle. In the central bore a spindle nut 53 is arranged, which converts the rotational movement of the spindle into a translational movement of the dip tube. Depending on the direction of rotation of the spindle thus the dip tube moves along the housing bore 16 back and forth. The stroke of the dip tube is limited by the two stops bottom hole 17 and motor flange 59. At the free end of the dip tube, the coupling to the adjusting ring 30 is arranged. For this purpose, the dip tube has a parallel-walled groove 55 which is arranged laterally offset from the central bore in the dip tube and is provided for receiving a sliding pin 41. The sliding pin is additionally connected to the adjusting ring 30 by being rotatably disposed in a bore 32 in radially outwardly projecting tabs 33 of the adjusting ring 30. The backup of the stepped slide pin in the holes can be done very compact and reliable with a locking ring 42. After the stepped sliding pin has been pushed all the way into the holes, the locking ring 42 is inserted into a designated groove in the front hole 32 on the front side of the pin. In the area of the tabs, the dip tube is laterally tapered.

In order to achieve the desired sealing of the suction region of the compressor to the actuator according to the invention, the central bore in the dip tube is formed as a blind hole and the dip tube in the housing bore 16 optionally sealed by piston sealing ring 56. The sealing ring is arranged in a groove provided for this purpose in the dip tube.

The actuator used is inexpensive and can be installed very compact. In addition, the illustrated embodiment is quite in terms of vibration and temperature loads, since no loose parts interact over multiple joints and angulations. List of Reference Symbols Inner housing Retaining rib Central body Outer housing Part Housing cover Housing cover Housing bore Bore bottom Guide vane Blade profile Vane shaft Adjusting lever for moving the guide vanes Ball bearing shoe Adjusting ring for moving the guide vanes via the adjusting levers Groove for receiving sliding shoe Ring bore for receiving sliding pin Tabs Sliding pin Circlip Actuator device Actuator, linear motor Spindle Spindle nut Sliding element, immersion tube Groove Sealing ring Connection cable Fastener Motor flange

Claims

PAT EN TA NSPR O CHE

1. compressor with an adjustable pre-whirling guide device for generating a pre-whirl in the intake region of the compressor, which pre-whirling guide device comprises a pivotable adjusting ring (30) for adjusting the guiding elements (20) of the guiding device and an actuator (50) for driving the adjusting ring (30) via a tangential to the adjusting ring (30) movable element (54), characterized in that the suction of the compressor to the actuator (50) is sealed off, and that the sealing by the tangential to the adjusting ring movable element (54).

2. A compressor according to claim 1, wherein the movable element (54) is guided in a tangential to the adjusting ring extending housing bore (16), and the housing bore (16) by the movable element (54) is sealed.

3. Compressor according to one of claims 1 or 2, wherein the displaceable element (54) comprises a sealing ring (56) for sealing the housing bore (16).

4. Compressor according to one of claims 1 to 3, wherein the actuator (50) a

Threaded spindle drives, which in a spindle nut (53) engages, which is connected to the displaceable element (54).

5. Compressor according to one of claims 1 to 3, wherein the actuator (50) drives a threaded spindle which engages in a spindle nut (53) which is arranged in a in the displaceable element (54) embedded blind hole.

6. A compressor according to any one of claims 1 to 5, wherein the movable member (54) is coupled to the adjusting ring (30) by a sliding pin (41), which on the adjusting ring (30) is arranged in a groove (55), which is embedded in the movable element, engages.

7. A compressor according to any one of claims 1 to 6, wherein the actuator (50) is an electric stepper motor.

8. Exhaust gas turbocharger, comprising a compressor according to one of the preceding claims.