The invention relates to a sliding cam system with at least one sliding cam that is arranged locked in rotation, but movable in the axial direction on at least one axially fixed base shaft for forming a camshaft of a reciprocating piston internal combustion engine, with at least one actuator device for adjusting the sliding cam into different axial positions by means of at least one actuator pin that can be engaged in at least one sliding groove on the periphery of the sliding cam, wherein the actuator device has a machine-fixed housing and the sliding grooves are arranged in a groove section of the sliding cam, and with a bracket that surrounds the groove section by means of side shoulders and is guided parallel to the base shaft and is provided with an opening in the area of the actuator pins.
Such a class-forming sliding cam system is known from DE 10 2011 050 484 A1. In that sliding cam system, the locking device is oriented perpendicular to the actuator device and is guided separately from this on a cylinder head cover of the reciprocating piston internal combustion engine. This construction therefore requires a large installation space that is not available in smaller internal combustion engines. Furthermore, the angular bracket has no axial guide, so that it is guided on the outer envelope circle of the groove section and rubs against it here. The shoulders on the bracket corresponding to the flanks of the groove section are extended in the circumferential direction and thus have a heavy construction. These extended shoulders, however, are required to be able to absorb the torque when moving from one axial position of the locking device to another. The locking device is not able to absorb additional forces here axial to the actuator pins.
The objective of the invention is to improve a sliding cam system of the class-forming type so that the mentioned disadvantages are eliminated and a stable, guided bracket is provided, which is able to absorb forces and fulfill a guiding function.
According to the invention, this objective is achieved in that the sliding cam has at least two sliding grooves that have different depths at least in some parts, the bracket is guided in the actuator device, and a positive-fit depth stop device is provided between the bracket and the actuator pin(s). The guidance of the bracket in the actuator device ensures that the bracket is guided exactly and forces as well as other tasks in connection with the actuator pins can be transferred. The bracket is therefore able to form a positive-fit depth stop device for the actuator pins, through which the actuator pins are held in the sliding grooves constructed with different depths at least in some parts. Here, the switching of the depth stop device is realized by the movement of the bracket, wherein the movement of the bracket is otherwise realized by the movement of the sliding cam.
In another construction of the invention it is provided that at least one bar projecting in the direction toward the actuator pins is built on the opening and that the actuator pins have a projecting ring that is constructed as a stop on the bar. Here, the ring has a position on the actuator pin such that the end of the actuator pin contacts the groove base of the less deep sliding groove when the lower edge of the ring contacts the upper edge of the bar. The bar and the ring on the actuator pin ensure that, in this position, the relevant actuator pin can reach only the less deep sliding groove. In order to also reach the deeper sliding groove, it is provided that the bar has at least one, preferably two cut-outs whose size enables movement of the ring through the bar. Therefore, when the bracket is moved sufficiently far that the cut-out matches the allocated actuator pin, said pin can pass, together with the ring, through the cut-out so that the actuator pin also reaches, in this position of the bracket, the deeper sliding groove. If the bracket is moved in this position, the bar engages behind the ring on the opposite side and prevents the actuator pin from leaving the deeper sliding groove unexpectedly. Only when the other second cut-out again matches the actuator pin and the ring can this leave the deepest sliding groove and move back into the actuator device. To ensure this, the distance between the lower edge of the ring/upper edge of the bar and the upper edge of the ring/lower edge of the bar is essentially adapted to the difference in the depths of the sliding grooves.
The bracket can be simultaneously connected to a device for locking the sliding cam in the different axial positions, wherein depressions are provided on the bracket in which spring-loaded locking bodies guided on the actuator device engage. However, a different locking device could also be provided that has, e.g., spring-loaded locking bodies in the base shaft that correspond to inner channels on the sliding cam.
The invention is described in the drawings:
In
Instead of the rings 16, 17 that can prevent the actuator pins 7 and 8 with one side from moving into and with the other side from moving out from the deeper groove 4, two recesses can also be machined on the actuator pins 7 and 8, which can take over the tasks of the rings 16, 17 for modified dimensions of the bars 14 and 15 and also of the cut-outs 18 and optionally their positions.
The bracket 9 therefore forms a positive-fit depth stop for the actuator pins 7, 8 so that these are held in the sliding grooves 3 and 4 with different depths. The bracket 9 also has sufficient strength in its position because it is guided exactly in the actuator device.
Number | Date | Country | Kind |
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10 2014 214 259 | Jul 2014 | DE | national |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/DE2015/200286 | 4/29/2015 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2016/012012 | 1/28/2016 | WO | A |
Number | Name | Date | Kind |
---|---|---|---|
8191524 | Elendt | Jun 2012 | B2 |
20100224154 | Elendt et al. | Sep 2010 | A1 |
Number | Date | Country |
---|---|---|
102009053116 | Sep 2010 | DE |
102011050484 | Nov 2012 | DE |
102012103750 | Oct 2013 | DE |
102012103751 | Oct 2013 | DE |
2015058745 | Apr 2015 | WO |
Number | Date | Country | |
---|---|---|---|
20170167324 A1 | Jun 2017 | US |