Field of the Invention

[0001] The present invention relates to a coupling device for an adjustment device, an adjustment device, and an exhaust gas turbocharger with an adjustment device. Background Information

[0002] Increasingly more vehicles of the more recent generation are equipped with turbocharger s, in particular exhaust gas turbochargers. Known turbochargers have a turbine housing, a compressor housing, and a bearing housing which is conventionally connected to the turbine housing on the turbine side and to the compressor housing on the compressor side. A shaft, which supports the turbine wheel and the compressor wheel, is mounted in the bearing housing.

[0003] Modern exhaust gas turbochargers are often equipped with an adjusting device, with the aid of which the performance characteristic of the exhaust gas turbocharger may be adjusted or changed. Known adjusting devices are, for example, a variable turbine geometry (VTG) and a waste gate valve. A variable turbine geometry thereby corresponds to an adjustable guide apparatus for changing an inflow to a turbine wheel of the turbine. By changing the inflow, in particular the flow velocity of the exhaust gas guided to the turbine wheel may be changed, which leads to a corresponding performance change of the turbocharger. In contrast thereto, a waste gate valve corresponds essentially to an adjustable bypass for circumventing the turbine wheel. To actuate an adjusting device of this type, an adjustment device may be used. This includes, in general, an actuator for generating adjusting movements and a coupling device with a coupling rod for transmitting the adjusting movements from the actuator to the adjusting device. During assembly of the adjustment device, the components (actuator, coupling rod, adjusting device) must be coupled to one another. A firmly prescribed alignment or orientation of the components to one another is to be maintained thereby. In known adjustment devices and/or coupling devices, an assembly in differing orientations is possible. This has the result that the components are incorrectly connected to one another during assembly to a certain extent; a follow- up examination is necessary, and incorrectly assembled adjustment devices must be disassembled and reassembled.

[0004] The object of the present invention is correspondingly to provide a coupling device for an adjustment device which prevents an incorrect assembly of the adjustment device.

Brief Summary of the Invention

[0005] The present invention relates to a coupling device for an adjustment device according to Claim 1, an adjustment device according to Claim 7, and an exhaust gas turbocharger according to Claim 14.

[0006] The coupling device according to the invention comprises a coupling rod for transmitting an adjusting movement from an actuator, wherein the coupling rod has a first coupling point with a first through opening on at least one first end. The coupling device additionally includes a first bush which is arranged in the through opening, wherein the first bush has a collar on one end which is designed to prevent an incorrect assembly position of the coupling device during the assembly of the adjustment device. It is advantageous in such a coupling device that an incorrect alignment or orientation of the components of the adjustment device is prevented during assembly by the configuration of the bush according to the invention. Thus, a correct assembly position of the coupling device is guaranteed. The coupling device according to the invention thus realizes the Poka Yoke principle for the assembly of the adjustment device in a simple way. Advantages resulting herefrom include a lower time expenditure already during assembly, savings of a final check for these components, and no reworking to correct an incorrect assembly position. This in turn leads to cost savings during the manufacturing process. [0007] In embodiments, the bush may have a radially extending shoulder and the collar may extend out from the collar in the axial direction. An outer radial surface of the shoulder may interact with an outer surface of the coupling rod in the area of the coupling point to define the position of the bush in the through opening of the coupling rod. An inner radial surface of the shoulder may be suited for defining the position of a coupling element in the bush.

[0008] In embodiments, which may be combined with all previously described embodiments, an outer diameter DAB of the bush in the area of the collar may be greater than an inner diameter Dm of the through opening.

[0009] In embodiments, which may be combined with all previously described embodiments, an inner diameter DIB of the bush in the area of the collar may be greater than an inner diameter Dm of the through opening.

[0010] In embodiments, which may be combined with all previously described embodiments, the bush may be press fitted in the through opening.

[0011] In embodiments, which may be combined with all previously described embodiments, the coupling rod may have a second coupling point with a second through opening, in which a second bush is arranged, on a second end. In embodiments, the second bush may be configured according to the first bush.

[0012] In embodiments, which may be combined with all previously described embodiments, the coupling rod may be a punch component, a forged component, or a laser-cut component.

[0013] In embodiments, which may be combined with all previously described embodiments, the coupling rod may be manufactured from plastic, metal, or steel, in particular stainless steel, and optionally has a protective coating, in particular made of zinc. [0014] In embodiments, which may be combined with all previously described embodiments, the bush may be manufactured from metal, in particular stainless steel, plastic, in particular a heat-resistant plastic, or a ceramic. [0015] The invention additionally includes an adjustment device for a turbocharger comprising at least one coupling element and a coupling device according to any one of the previously described embodiments, wherein the coupling element is arranged to be rotatable in the bush. [0016] In embodiments of the adjustment device, the coupling element may be configured in the form of a bolt. The bolt may have a ring, wherein the ring may interact with the inner radial surface of the shoulder to define the position of the bolt in the coupling device. The diameter DBR of the bolt may be smaller in the area of the ring than the inner diameter Dm of the bush in the area of the collar so that the collar may radially surround the ring at least partially.

[0017] In embodiments of the adjustment device, which may be combined with all previously described embodiments, the coupling element may have a circumferential groove in the area of one end, and the coupling element is secured in the bush by a securing means which is arranged in the circumferential groove. The collar of the bush may prevent an application of the securing means in an incorrect assembly position of the coupling device with respect to the coupling element. [0018] In embodiments of the adjustment device, which may be combined with all previously described embodiments, the adjustment device may additionally comprise an actuator for generating an adjustment movement, wherein the coupling element is connected to the actuator. In embodiments, a coupling device may be provided with first and second coupling points and first and second bushes, and a first and a second coupling element, wherein the first coupling element is connected to the actuator and is arranged in the first bush, and the second coupling element is arranged in the second bush. [0019] The invention additionally comprises an exhaust gas turbocharger for an internal combustion engine comprising a turbine, an adjusting device for changing a performance characteristic of the exhaust gas turbocharger, and an adjustment device according to one of the previously described embodiments for actuating the adjusting device.

[0020] In embodiments of the exhaust gas turbocharger, the adjustment device may have first and second coupling points and first and second coupling elements, and the second coupling element may be connected to the adjusting device or to a part of the adjusting device.

[0021] In embodiments of the exhaust gas turbocharger, which may be combined with all previously described embodiments, the adjusting device may comprise a variable turbine geometry or an adjustable bypass for circumventing a turbine wheel of the turbine.

[0022] Additional details and features of the invention are subsequently described by way of the figures. Brief Description of the Drawings

Figure 1 shows two perspective views of one first embodiment of the coupling device according to the invention; Figure 2 shows two side views of the coupling device of the embodiment from Figure 1.

Detailed Description of the Invention [0023] In the following, embodiments for the coupling device according to the invention in combination with the adjustment device according to the invention or the exhaust gas turbocharger according to the invention will be described by means of the figures. [0024] Figure 1 shows two perspective views of an adjustment device or a part of an adjustment device 10 with a coupling device 100. The top depiction in Figure 1 shows an adjustment device 10 which was correctly assembled. The bottom depiction in Figure 1 shows an adjustment device 10, in which the assembly was carried out erroneously or is prevented. Correspondingly, Figure 2 above shows a side view of correctly assembled adjustment device 10 and the bottom depiction shows in turn an incorrect assembly or an attempt at an incorrect assembly.

[0025] Coupling device 100 comprises a coupling rod 110 for transmitting an adjusting movement from an actuator. A first coupling point 112, which has a first through opening 114, is provided on at least one end of coupling rod 110. Coupling device 100 additionally includes a first bush 120 which is arranged in through opening 114, wherein first bush 120 has a collar 122 on one end (see Figure 1 and Figure 2). The collar is designed to prevent an incorrect assembly position of coupling device 100 during the assembly of adjustment device 10. This is represented by way of illustration in Figure 1 and Figure 2. The respective upper depictions show a correctly assembled adjustment device 10, while in the respectively lower depictions, an incorrectly assembled adjustment device 10 may be seen. It is advantageous in coupling device 100 that an incorrect alignment or orientation of the components of adjustment device 10 during assembly is prevented by the configuration of bush 120 according to the invention. Thus, a correct assembly position of coupling device 100 is guaranteed. Coupling device 100 according to the invention thus realizes the Poka Yoke principle for the assembly of adjustment device 10 in a simple way. Advantages resulting herefrom include a lower time expenditure already during assembly, savings of a final check for these components, and no reworking to correct an incorrect assembly position. This in turn leads to cost savings during the manufacturing process.

[0026] Coupling rod 110 may, depending on use, also have a second coupling point with a corresponding through opening on its second end. A second bush may be arranged in this through opening. This may be a conventional bush, as a single bush 120 with collar 122 is sufficient to ensure the correct assembly position. Alternatively, the second bush may be configured with a collar corresponding to first bush 120. By this means, production advantages may result based on the use of identical parts.

[0027] Coupling rod 110 may, for example, be a punch component, a forged component, or a laser-cut component. As the material, for example, plastic, metal, or steel, in particular stainless steel, may be used for coupling rod 110. Optionally, a protective coating, in particular made from zinc, may be provided which protects against corrosion and/or mechanical stresses. [0028] Bush 120, or the bushes, may be manufactured from metal, in particular stainless steel, plastic, in particular a heat-resistant plastic, or a ceramic. The material of the bush may, for example, be selected based on the intended use of adjustment device 10 and the loads to be thus expected for bush 1202 [sic: 120].

[0029] In the embodiments shown in Figure 1 and Figure 2, bush 120 has a radially extending shoulder 124, wherein collar 122 extends out from shoulder 124 in the axial direction. The axial direction thereby refers to a direction parallel to a longitudinal axis of bush 120 (see Figure 2 bottom). In other words, bush 120 has two areas with different diameters which are connected to one another via a step (very clear in Figure 2). The first area with the smaller diameter is arranged in through opening 114, and the second area with the larger diameter forms collar 122, which is arranged, together with the step, outside of through opening 114. Shoulder 124 is formed by the step. An outer radial surface of shoulder 124 interacts with an outer surface of coupling rod 110 in the area of coupling point 112 to define the axial position of bush 120 in through opening 114 of coupling rod 110 (see likewise Figure 2). An inner radial surface of shoulder 124 is suited for defining the position of a coupling element 200 in bush 120 (further details regarding coupling element 200 are further below in the text). [0030] The geometric configuration of bush 120 is depicted with respect to coupling rod 100 in Figure 2 top. Outer diameter DAB of bush 120 is greater in the area of collar 122 than inner diameter Dm of through opening 114. Inner diameter DIB of bush 120 is likewise greater in the area of collar 122 than inner diameter DID of through opening 114. This is, however, not mandatorily necessary, since diameter Dm may be adjusted depending on a coupling element 200 which interacts with the bush. Diameter Dm of through opening 114 and the diameter of the bush in this area may be configured such that bush 120 may be press fitted in through opening 114. Suitable alternatives to the press fitting for fixing bush 120 in through opening 114 of coupling rod 110 include, for example, shrinking, riveting, clipping, welding, and caulking, among others.

[0031] As already mentioned, coupling device 100 according to the invention may be used as a component in an adjustment device 10 for a turbocharger. Adjustment device 10 has at least one coupling element 200, wherein coupling element 200 is arranged to be rotatable in bush 120 of coupling device 100. In the example from Figure 1 and Figure 2, coupling element 200 is configured in the form of a bolt. The bolt has a ring 220 which interacts with the inner radial surface of shoulder 124 to define the position of the bolt in coupling device 100. In other words, the bolt has a first area with a first diameter and a second area with a second diameter, wherein the first diameter is smaller than the second diameter. The second area with the larger diameter defines ring 220. Diameter DBR of the bolt is thereby smaller in the area of ring 220 than inner diameter Dm of bush 120 in the area of collar 122 so that collar 122 radially surrounds ring 220 at least partially when coupling element 200 and coupling device 100 are assembled in the correct orientation to one another (see the respective top depictions in Figure 1 and Figure 2).

[0032] Coupling element 200, the bolt in the example shown, has a circumferential groove 210 in the area of one end. When coupling element 200 is correctly arranged in bush 120, coupling element 200 may be secured in bush 120 by a securing means 300 which is arranged in circumferential groove 210 (see the respective top depictions in Figure 1 and Figure 2). Securing means 300 may be, for example, a securing ring or a locking washer. It is advantageous in adjustment device 10 according to the invention, that collar 122 of bush 120 prevents an application of securing means 300 in an incorrect assembly position of coupling device 100 with respect to coupling element 200. This functions in that collar 122 of bush 120 extends around coupling element 200 in the area of circumferential groove 210 so that securing means 300 may not be applied. Expressed in another way: when coupling element 200 is inserted incorrectly into the bush (e.g. rotated 180° to the correct assembly position), then collar 122 of bush 120 surrounds the end of coupling element 200 in the area of circumferential groove 210 so that it is not possible to apply securing means 300. Thus, the installer is forced, according to the Poka Yoke principle, to carry out the assembly with the correct orientation of the components (coupling rod 110, coupling element 200) to one another. Consequently, in this area, there may be no incorrectly assembled adjustment devices, for which reason no follow up examinations are necessary. [0033] Adjustment device 10 may additionally include an actuator (not shown in Figure 1 or Figure 2) to generate an adjusting movement, wherein coupling element 200 is connected to the actuator. As already previously described above, coupling device 100 may have two coupling points, two through openings, and correspondingly two bushes arranged in the through openings. A corresponding adjustment device 10 then has first and second coupling elements, wherein first coupling element 200 may be connected to the actuator and may be arranged in first bush 120, and the second coupling element may be arranged in the second bush, or vice versa. As likewise previously mentioned, the second bush may be configured as a conventional bush or corresponding to first bush 120.

[0034] The invention additionally comprises an exhaust gas turbocharger for an internal combustion engine comprising a turbine, an adjusting device for changing a performance characteristic of the exhaust gas turbocharger, and an adjustment device 10, according to the invention described above, for actuating the adjusting device. Adjustment device 10 has two coupling elements, wherein one of the coupling elements is fixed to an actuator and the second coupling element is connected to the adjusting device or to a part of the adjusting device. The two coupling elements may be configured in the form of a bolt with a corresponding circumferential groove in which a corresponding securing means is arranged. However, a coupling device 100 according to the invention comprising a single bush 120 with collar 122 on one side of coupling rod 110 is sufficient for guaranteeing the correct position or orientation of coupling rod 110 during assembly. The coupling point on the second end of coupling rod 110 may thus be configured in an arbitrarily different way. The adjusting device may, for example, comprise a variable turbine geometry or an adjustable bypass for circumventing a turbine wheel of the turbine.

[0035] Although the present invention has been described above and is defined in the attached claims, it should be understood that the invention may also be alternatively defined according to the following embodiments: 1. A coupling device (100) for an adjustment device (10), comprising

a coupling rod (110) for transmitting an adjusting movement from an actuator, wherein the coupling rod (110) has a first coupling point (112) with a first through opening (114) on at least one first end, and

a first bush (120) which is arranged in the through opening (114), characterized in that the first bush (120) has a collar (122) on one end which is designed to prevent an incorrect assembly position of the coupling device (100) during the assembly of the adjustment device (10).

2. The coupling device according to Embodiment 1, characterized in that the bush (120) has a radially extending shoulder (124) and the collar (122) extends out from the shoulder (124) in the axial direction.

3. The coupling device according to Embodiment 1 or Embodiment 2, characterized in that an outer diameter (DAB) of bush (120) is greater in the area of the collar (122) than an inner diameter (Dm) of the through opening

(114).

4. The coupling device according to any one of the preceding embodiments, characterized in that an inner diameter (DB) of the bush (120) is greater in the area of the collar (122) than an inner diameter (Dm) of the through opening (114).

5. The coupling device according to any one of Embodiments 2 through 4, characterized in that an outer radial surface of the shoulder (124) interacts with an outer surface of the coupling rod (110) in the area of the coupling point (112) to define the position of the bush (120) in the through opening (114) of the coupling rod (110). The coupling device according to any one of Embodiments 2 through 5, characterized in that an inner radial surface of the shoulder (124) is suited for defining the position of a coupling element (200) in the bush (120).

The coupling device according to any one of the preceding embodiments, characterized in that the bush (120) is press fitted in the through opening (114).

The coupling device according to any one of the preceding embodiments, characterized in that the coupling rod (110) has a second coupling point with a second through opening, in which a second bush is arranged, on a second end, in particular wherein the second bush is configured corresponding to the first bush (120).

The coupling device according to any one of the preceding embodiments, characterized in that the coupling rod (110) is a punch component, a forged component, or a laser-cut component.

The coupling device according to any one of the preceding embodiments, characterized in that the coupling rod (110) is manufactured from plastic, metal, or steel, in particular stainless steel, and optionally has a protective coating, in particular made of zinc.

The coupling device according to any one of the preceding embodiments, characterized in that the bush is manufactured from metal, in particular stainless steel, plastic, in particular a heat-resistant plastic, or a ceramic.

An adjustment device (10) for a turbocharger, comprising

at least one coupling element (200), and

a coupling device (100) according to any one of the preceding claims [sic: embodiments], wherein the coupling element (200) is arranged to be rotatable in the bush (120). 13. The adjustment device according to Embodiment 12, characterized in that the coupling element (200) is configured in the form of a bolt.

14. The adjustment device according to Embodiment 13, characterized in that the bolt has a ring (220), wherein the ring (220) interacts with the inner radial surface of the shoulder (124) to define the position of the bolt in the coupling device (100).

15. The adjustment device according to Embodiment 14, characterized in that the diameter (DBR) of the bolt is smaller in the area of the ring (220) than the inner diameter (DIB) of the bush (120) in the area of the collar (122) so that the collar (122) radially surrounds the ring (220) at least partially.

16. The adjustment device according to any one of Embodiments 12 through 15, characterized in that the coupling element (200) has a circumferential groove (210) in the area of one end, and the coupling element (200) is secured in the bush (120) by means of a securing means (300) which is arranged in the circumferential groove (210). 17. The adjustment device according to Embodiment 16, characterized in that the collar (122) of the bush (120) prevents the application of the securing means (300) in an incorrect assembly position of the coupling device (100) with respect to the coupling element (200). 18. The adjustment device according to any one of Embodiments 12 through 17, characterized in that the adjustment device (10) additionally comprises an actuator for generating an adjusting movement, wherein the coupling element (200) is connected to the actuator. 19. The adjustment device according to Embodiment 18, characterized in that a coupling device (100) is provided with first and second coupling points and first and second bushes, and that a first and a second coupling element (200) is provided, wherein the first coupling element (200) is connected to the actuator and is arranged in the first bush (120), and the second coupling element is arranged in the second bush. An exhaust gas turbocharger for an internal combustion engine, comprising

a turbine,

an adjusting device for changing a performance characteristic of the exhaust gas turbocharger, and

an adjustment device according to Embodiment 19 for actuating the adjusting device. The exhaust gas turbocharger according to Embodiment 20, characterized in that the second coupling element is connected to the adjusting device or to a part of the adjusting device. The exhaust gas turbocharger according to Embodiment 20 or Embodiment 21, characterized in that the adjusting device comprises a variable turbine geometry, or

that the adjusting device comprises an adjustable bypass for circumventing a turbine wheel of the turbine.