Camshaft arrangement

Abstract

A camshaft arrangement comprising a camshaft, a vane-type camshaft phaser attached to a first end of the camshaft, a valve actuating arrangement and an oil control valve. The oil control valve comprises an elongated valve member arranged centrally inside the camshaft. The elongated valve member can be adjusted in a longitudinal direction of the camshaft to control the oil flow to the vane-type camshaft phaser by actuation of an actuator. The valve actuating arrangement comprises a first valve actuating configuration attached to the camshaft and a second valve actuating configuration comprising an actuation arm connected to the actuator. The first valve actuating configuration is arranged to be actuated by the actuation arm of the second valve actuating configuration.

Claims

1. A camshaft arrangement, comprising: a camshaft, a vane-type camshaft phaser attached to a first end of the camshaft, a valve actuating arrangement and an oil control valve, wherein the oil control valve comprises an elongated valve member arranged centrally inside the camshaft, where the elongated valve member can be adjusted in a longitudinal direction of the camshaft so as to control the oil flow to the vane-type camshaft phaser, wherein the valve actuating arrangement comprises a first valve actuating configuration attached to the camshaft and a second valve actuating configuration comprising an actuation arm connected to an actuator, the first valve actuating configuration being arranged to be actuated by the actuation arm of the second valve actuating configuration, thereby adjusting the elongated valve member.

2. The camshaft arrangement according to claim 1, wherein the first valve actuating configuration comprises an actuation ring mounted around the camshaft and an actuation ring member being attached to the actuation ring.

3. The camshaft arrangement according to claim 2, wherein the actuation ring member comprises an actuation pin attached to the actuation ring arranged to run through the camshaft.

4. The camshaft arrangement according to claim 3, wherein the camshaft comprises longitudinal openings for the actuation pin.

5. The camshaft arrangement according to claim 1, wherein the actuation arm comprises an actuation arm member arranged to actuate the first valve actuating configuration.

6. The camshaft arrangement according to claim 5, wherein the actuation arm member comprises a bearing surface adapted to glide against the actuation ring.

7. The camshaft arrangement according to claim 6, wherein the bearing surface is convex.

8. The camshaft arrangement according to claim 5, wherein the angular extension of the actuation arm member is less than 180.

9. The camshaft arrangement according to claim 5, wherein the actuation arm member is arranged to glide on the camshaft.

10. The camshaft arrangement according to claim 5, wherein the actuation arm member is arranged at a distance from the camshaft.

11. The camshaft arrangement according to claim 5, wherein the actuation arm member comprises a fork.

12. The camshaft arrangement according to claim 1, wherein the oil control valve comprises an oil control valve engagement member arranged to interact with the actuation ring member of the first valve actuating configuration.

13. An internal combustion engine comprising a camshaft arrangement according to claim 1.

14. The internal combustion engine according to claim 13, further comprising a cam cover, wherein the actuator is mounted outside of the cam cover.

15. A vehicle comprising an internal combustion engine according to claim 13.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the description of the invention given below reference is made to the following figure, in which:

(2) FIG. 1 schematically shows a cross-sectional view of a camshaft arrangement according to the invention,

(3) FIG. 2 schematically shows an exploded view of a camshaft arrangement according to the invention, and

(4) FIG. 3 schematically shows a cross-sectional view of a combustion engine with a camshaft arrangement according to the invention.

DESCRIPTION OF EMBODIMENTS

(5) FIG. 1 schematically shows a cross-sectional view of a camshaft arrangement 1 according to the invention. The camshaft arrangement 1 comprises a valve actuating arrangement 2, a camshaft 1a having an extension in a longitudinal direction X and at a first end 3 of the camshaft 1a, a vane-type camshaft phaser 4 is attached to an input sprocket 5 of the camshaft 1a. The input sprocket 5 is connected to the crankshaft by a timing belt or tinning chain (not shown). The function of the vane-type camshaft phaser 4 and its attachment to the camshaft 1a are known in the art. An oil control valve 6 which comprises an elongated valve member 7 is arranged centrally inside the camshaft 1a. The elongated valve member 7 can be adjusted in a longitudinal direction of the camshaft 1a so as to control an oil flow to the vane-type camshaft phaser 4 by actuation of an actuator 8 in order to change the timing between the camshaft 1a and a crankshaft of a combustion engine.

(6) The valve actuating arrangement 2 comprises a first valve actuating configuration 9 attached to the camshaft 1a and a second valve actuating configuration 10. The second valve actuating configuration comprises an actuation arm 11 and an actuator 8, where the actuation arm is connected to the actuator 8. The first valve actuating configuration 9 is arranged to be actuated by the actuation arm 11 of the second valve actuating configuration 10. The first valve actuating configuration 9 is attached to the camshaft 1a and thus rotates with the camshaft 1a. The first valve actuating configuration 9 comprises an actuation ring 12 mounted around the camshaft 1a and is attached to the camshaft 1a by means of that an actuation ring member 13 is arranged to run through the camshaft 1a and the actuation ring 12. The actuation ring member 13 is in the present example an actuation pin. The actuation pin runs in longitudinal openings 14 arranged on opposite sides of the camshaft 1a. The first valve actuating configuration 9 thus rotates with the camshaft 1a and can glide a distance along the camshaft 1a corresponding to the length of the longitudinal openings 14. The longitudinal openings 14 have essentially semi-circular ends and each longitudinal opening has a length of approximately 2-10 mm, more specifically approximately 4 mm, as measured between centres of radii of the semi-circular ends of the longitudinal openings. Thus, the first valve actuating configuration can move approximately 2-10 mm along the camshaft 1a, more specifically approximately 4 mm.

(7) To the actuation arm 11 of the second valve actuating configuration 10, an actuation arm member 15 is attached. In the example of FIG. 1, the actuation arm member 15 is positioned in a vertical direction above the camshaft 1a. The actuation arm member 15 can be either in a position such that it glides against the camshaft 1a when the camshaft 1a rotates or in a position such that it does not lie against the camshaft 1a and a gap is present between the camshaft 1a and the actuation arm member 15. The actuation arm member 15 abuts the actuation ring 12 of the first valve actuating configuration 9 as long as the actuator 8 is powered. The actuator 8 moves the actuation arm 11 and thus the actuation arm member 15 in a longitudinal direction along the camshaft 1a thereby moving the first valve actuating configuration 9. The first valve actuating configuration 9 are arranged to actuate an oil control valve engagement member 16 in order to move the oil control valve 6 between a first position and a second position. The actuation arm member 15 comprises a bearing surface 17 adapted to glide against the rotating actuation ring 12 when the second valve actuating configuration 10 actuates the first actuating configuration. The bearing surface 17 may be convex.

(8) FIG. 2 schematically shows an exploded view of a camshaft arrangement 1 according to the invention. From left to right, FIG. 2 shows the oil control valve 6 with the oil control valve engagement member 16 extending from it. The oil control valve engagement member 16 is an extension of the elongated valve member 7 or valve piston inside the oil control valve 6. Next, FIG. 2 shows the vane-type camshaft phaser 4, a support bearing 18 for supporting the camshaft 1a and a camshaft end section 19 arranged to engage with the camshaft phaser 4 and in which the oil control valve 6 is mounted. On the camshaft end section 19, the first valve actuating configuration 9, i.e. actuation ring 12 and actuation ring member 13, are attached. The camshaft end section 19 comprises longitudinal openings 14 through which the actuation pin runs attaching the actuating ring 12 to the camshaft 1a and in which the actuation pin can run in a direction along the camshaft 1a when actuated. As described above, the actuation pin of the first valve actuating configuration 9 is arranged to actuate the oil control valve engagement member 16 and thereby the oil control valve 6. Further, the second valve actuating configuration 10 are shown, comprising the actuator 8, an actuator housing 20 and the actuation arm 11 with the actuation arm member 15 attached to it. The actuation arm member 15 has a convex bearing surface 17 arranged to engage with the actuation ring. The angular extension of the actuation arm member 15 may be less than 180, more specifically less than 90, even more specifically less than 30. In the example of FIG. 2, the angular extension is approximately 15. In the inset figure, an alternative actuation arm member 15 can be seen. The alternative actuation arm member comprises a fork 21 glidably arranged on the camshaft 1a or arranged at a distance from the camshaft 1a as with the alternative example described above. A further alternative for the actuation arm member 15 is to have a circular actuation arm member, i.e. a ring enclosing the camshaft 1a.

(9) In the example of FIG. 2, the actuator 8 is a solenoid valve. The actuation arm 11 is attached to the actuator 8 such that its movement is restricted to movement in the longitudinal direction X. The actuator 8 can alternatively be an electric motor or a hydraulic actuator. FIG. 2 lastly shows the camshaft main section 22 with the first two cams 23.

(10) FIG. 3 schematically shows a cross-sectional view of a combustion engine 24 with a camshaft arrangement 1 according to the invention. An oil control valve return means 25 in the form of a spring is arranged at the outside of the oil control valve 6 in order to return the oil control valve 6 from its second position to its first position when the actuator 8 is no longer activated. Alternatively, the actuator 8 is a double acting actuator moving the entire first and second valve actuating configuration in both directions along the camshaft. This requires that the first and second valve actuating configurations are attached to each other.

(11) Further, the actuator 8 is placed outside of the combustion engine 24, in this particular example outside of and on top of a cam cover 26 of the combustion engine 24. The actuator 8 can alternatively be placed away from the cam cover 26 or on a side of the cam cover 26 depending on the design of the combustion engine and the amount of space available in the engine compartment.

(12) Reference signs mentioned in the claims should not be seen as limiting the extent of the matter protected by the claims, and their sole function is to make the claims easier to understand.

(13) As will be realised, the invention is capable of modification in various obvious respects, all without departing from the scope of the appended claims. Accordingly, the drawings and the description thereto are to be regarded as illustrative in nature, and not restrictive.