Camshaft adjusting system with flex pot for decoupling of the adjustment ranges

Abstract

A camshaft adjusting system (1) is provided for a first camshaft (2) and a second camshaft (3) which are arranged concentrically with respect to one another, the second camshaft (3) being arranged within the first camshaft (2). A vane-cell type hydraulic camshaft adjuster (4) is configured for adjusting the first camshaft (2) and an electric camshaft adjuster (5) is configured for adjusting the second camshaft (3). A front cover (7) which is fastened to a stator (6) of the hydraulic camshaft adjuster (4) and which closes off the camshaft adjuster (4) at a side facing away from the camshaft has an internal toothing (8) for supporting a flex pot (9) which is attached to the second camshaft (3) and which is designed for receiving torque from the electric camshaft adjuster (5). A camshaft adjusting unit having the camshaft adjusting system (1) and two camshafts (2, 3) is also provided.

Claims

1. A camshaft adjusting system for a first camshaft and a second camshaft which are arranged concentrically with respect to one another, the second camshaft being arranged within the first camshaft, the camshaft adjusting system comprising: a vane-cell type hydraulic camshaft adjuster configured for adjusting the first camshaft and including a stator and a front cover fastened to the stator that closes off the hydraulic camshaft adjuster at a side that is adapted to be facing away from the camshafts; an electric camshaft adjuster configured for adjusting the second camshaft; a flex pot which is configured to be attached to the second camshaft that receives torque from the electric camshaft adjuster; the front cover includes an internal toothing that supports the flex pot.

2. The camshaft adjusting system as claimed in claim 1, wherein the front cover is an integral constituent part of the stator.

3. The camshaft adjusting system as claimed in claim 1, wherein the front cover is a component that is separate from the stator.

4. The camshaft adjusting system as claimed in claim 1, wherein the front cover includes a stop component and the internal toothing is separate from the stop component.

5. The camshaft adjusting system as claimed in claim 4, wherein the stop component has a shoulder which prevents an axial movement of at least one of the flex pot or a rolling bearing outer shell in the flex pot in a direction of an electric motor of the electric camshaft adjuster.

6. The camshaft adjusting system as claimed in claim 4, wherein the stop component engages around the front cover.

7. The camshaft adjusting system as claimed in claim 6, wherein a frictional engagement is formed between the stop component and the front cover.

8. The camshaft adjusting system as claimed in claim 1, wherein the front cover has both a stop and the internal toothing.

9. The camshaft adjusting system as claimed in claim 8, wherein the stop includes a shoulder which prevents an axial movement of at least one of the flex pot or a rolling bearing outer shell in the flex pot in a direction of an electric motor of the electric camshaft adjuster.

10. The camshaft adjusting system as claimed in claim 1, further comprising an adapter part for conducting oil arranged in an axial direction between a rotor of the hydraulic camshaft adjuster and the flex pot.

11. The camshaft adjusting system as claimed in claim 1, further comprising an intermediate part by which the flex pot is adapted to be connected to the second camshaft.

12. The camshaft adjusting system as claimed in claim 1, further comprising an Oldham coupling by which the electric camshaft adjuster is adapted to be connected to the second camshaft.

13. A camshaft adjusting unit comprising the camshaft adjusting system as claimed in claim 1 and the first and second camshafts which are arranged concentrically with respect to one another.

14. A camshaft adjusting system comprising: a first camshaft; a second camshaft arranged concentrically inside the first camshaft; a vane-cell type hydraulic camshaft adjuster connected to the first camshaft and configured to adjust a relative rotational position of the first camshaft, the hydraulic camshaft adjuster including a stator and a front cover fastened to the stator that closes off the hydraulic camshaft adjuster at a side that is adapted to be facing away from the camshafts; an electric camshaft adjuster connected to the second camshaft and configured to adjust a relative rotational position of the second camshaft; a flex pot by which the second camshaft is connected to the electric camshaft adjuster, the flex pot receives torque from the electric camshaft adjuster; and the front cover includes an internal toothing that supports the flex pot.

15. The camshaft adjusting unit as claimed in claim 14, wherein the front cover is an integral constituent part of the stator.

16. The camshaft adjusting unit as claimed in claim 14, wherein the front cover includes a stop component and the internal toothing which is separate from the stop component.

17. The camshaft adjusting unit as claimed in claim 16, wherein the stop component has a shoulder which prevents an axial movement of at least one of the flex pot or a rolling bearing outer shell in the flex pot in a direction of an electric motor of the electric camshaft adjuster.

18. The camshaft adjusting unit as claimed in claim 14, wherein the front cover has both a stop and the internal toothing.

19. The camshaft adjusting unit as claimed in claim 18, wherein the stop includes a shoulder which prevents an axial movement of at least one of the flex pot or a rolling bearing outer shell in the flex pot in a direction of an electric motor of the electric camshaft adjuster.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The embodiments will be discussed in more detail with the aid of figures, in which various embodiments are illustrated and in which:

(2) FIG. 1 shows a longitudinal sectional view of a camshaft adjusting system in a first exemplary embodiment in a perspective illustration;

(3) FIG. 2 shows the first exemplary embodiment of the camshaft adjusting system shown in FIG. 1 in a longitudinal sectional view;

(4) FIG. 3 shows the first exemplary embodiment of the camshaft adjusting system in a perspective view obliquely from the rear;

(5) FIG. 4 shows the first exemplary embodiment of the camshaft adjusting system in a perspective view obliquely from the front;

(6) FIG. 5 shows a cross-sectional view of the camshaft adjusting system in the region of a cover toothing;

(7) FIG. 6 shows a cross-sectional view of the camshaft adjusting system in the region of a front cover;

(8) FIG. 7 is a perspective illustration of the front cover in a first exemplary embodiment;

(9) FIG. 8 is a longitudinal sectional view of the front cover illustrated in FIG. 7;

(10) FIG. 9 is a longitudinal sectional view of the camshaft adjusting system and a second exemplary embodiment;

(11) FIG. 10 is an exemplary illustration of the front cover in a second exemplary embodiment;

(12) FIG. 11 shows a longitudinal sectional view of the front cover illustrated in FIG. 10; and

(13) FIG. 12 shows a detail view XII from FIG. 11 in an enlarged illustration.

DETAILED DESCRIPTION

(14) The figures are merely of a schematic nature and serve only for the understanding of the embodiments. The same elements are denoted by the same reference designations.

(15) Features of the individual exemplary embodiments may also be realized in other exemplary embodiments. They are thus interchangeable with one another.

(16) FIGS. 1 to 6 show a camshaft adjusting system 1 in a first exemplary embodiment in different views. FIG. 1 shows the camshaft adjusting system 1 in a longitudinal sectional view. The camshaft adjusting system 1 serves for the adjustment of a first camshaft 2 and of a second camshaft 3, which are arranged concentrically with respect to one another, wherein the second camshaft 3 is arranged radially within the first camshaft 2. The first camshaft 2 is adjusted by a hydraulic vane-cell type camshaft adjuster 4, whereas the second camshaft 3 is adjusted by an electric camshaft adjuster 5. This means that the hydraulic camshaft adjuster 4 acts on the outer camshaft 2 in order to adjust a phase position of the latter, and the electric camshaft adjuster 5 acts on the inner camshaft 3 in order to adjust a phase position of the latter.

(17) The hydraulic vane-cell type camshaft adjuster 4 has inter alia a stator 6 which is closed off in an axial direction, on a side averted from the camshafts 2, 3, by an annular front cover 7. The front cover 7 has an internal toothing 8, that is to say a toothing which is formed at its inner diameter (see also FIGS. 7 and 8) and which serves for supporting a flex pot 9, which flex pot is attached to the second camshaft 3 and is designed for receiving torque from the electric camshaft adjuster 5. For this purpose, the internal toothing 8 of the front cover 7 meshes with an external toothing 10 of the flex pot 9, that is to say with a toothing which is formed on an outer diameter of the flex pot 9. Thus, the front cover 7 serves as an internal gear for the flex pot 9, and here, decouples the adjustment ranges for the first camshaft 2 and the second camshaft 3.

(18) With reference to FIGS. 1 and 2, the hydraulic camshaft adjuster 5 will be discussed in more detail below. As already mentioned above, the hydraulic camshaft adjuster 4 has a stator 6 and a radially inner rotor 11 arranged concentrically with respect to said stator, wherein the rotor 11 is mounted so as to be rotatable relative to the stator 6. In the exemplary embodiment shown here, the stator 6 is formed integrally with a drive wheel 12. The drive wheel 12, which is designed here as a sprocket, is thus coupled to the camshafts 2, 3 for the introduction of torque.

(19) The electric camshaft adjuster 5 has an electric motor 13, which has an output shaft 14. This output shaft is coupled in torque-transmitting fashion via an Oldham coupling 15 to the flex pot 9. The flex pot 9 is in turn attached via an intermediate part 16 and a central bolt 17 to the inner, that is to say second, camshaft 3. The Oldham coupling 15 can compensate a radial offset of two parallel shafts. The flex pot 9 is mounted by a rolling bearing 18 on its inner diameter.

(20) Between the second camshaft 3 and the flex pot 9, in an axial direction, there is arranged an (additional) adapter part 19 which has inner channels 20 and an annular channel 21 on the outer diameter. These channels serve for the feed and discharge of the control oil into and out of the pressure chambers A and B of the hydraulic camshaft adjuster 4, which are formed by the stator 6 and the rotor 11. Between the outer diameter of the adapter part 19 and the inner diameter of the rotor 11, there is formed a support or plain bearing 22 for the flex pot 9.

(21) The hydraulic camshaft adjuster 4 is closed off in an axial direction on both sides by in each case one cover, wherein a first cover, arranged on the left in FIG. 2 (that is to say on the side averted from the camshafts 2, 3), corresponds to the front cover 7, and one arranged on the right in FIG. 2 (on the side facing toward the camshafts 2, 3) is formed as an annular cover 23 with a rotor contact flange 24.

(22) The rotor 11 is mounted on the first camshaft 2 by a bearing point 25. In order to prevent an axial displacement away from the camshafts 2, 3, in particular of the construction comprising the flex pot 9, a sheet-metal cover 26, which serves as a separate stop cover, is provided in the first embodiment. The sheet-metal cover 26 is, for this purpose, installed with an interference fit onto the outer diameter of the front cover 7.

(23) As can be seen in particular in FIGS. 3, 5 and 6, the front cover 7, the hydraulic camshaft adjuster 4, in the region of the stator 6, and the cover 23 are connected to one another in an axial direction by means of multiple bolts 27. The bolts 7 are, as shown here, arranged so as to be distributed uniformly over the circumference (see FIGS. 3, 5 and 6). For this purpose, the corresponding components have openings 28, as shown by way of example in FIG. 7 on the front cover 7.

(24) FIGS. 9 to 12 show the camshaft adjusting system 1 in a second exemplary embodiment. The second embodiment corresponds substantially to the first embodiment, for which reason only the differences will be discussed below.

(25) By contrast to the first exemplary embodiment shown in FIGS. 1 to 8, the second exemplary embodiment has no sheet-metal cover 26 which serves as a stop component. For this, the front cover 7 has, on one axial side (the side averted from the camshafts), a radially inwardly projecting ring 29, which in this case serves as the stop component (see in particular FIGS. 10 to 12). Thus, in the second embodiment, both the toothing portion 8, which serves as internal gear for the flex pot 9, and the stop component are integrated in the front cover 7.

(26) From the detail view in FIG. 12, it can be seen that the ring 29 is spaced apart from the toothing 8 by means of a bevel such that smooth running in the toothed engagement between the internal toothing 8 of the front cover 7 and the external toothing 10 of the flex pot 9 is not impaired.

LIST OF REFERENCE DESIGNATIONS

(27) 1 Camshaft adjusting system 2 First camshaft 3 Second camshaft 4 Hydraulic camshaft adjuster 5 Electric camshaft adjuster 6 Stator 7 Front cover 8 Internal toothing 9 Flex pot 10 External toothing 11 Rotor 12 Drive gear 13 Electric motor 14 Output shaft 15 Oldham coupling 16 Intermediate part 17 Central disk 18 Rolling bearing 19 Adapter part 20 Inner channel 21 Annular channel 22 Support/plain bearing 23 Cover 24 Rotor contact flange 25 Bearing point 26 Sheet-metal cover 27 Bolt 28 Opening 29 Ring 30 Bevel