The invention relates to a switchable finger lever of a valve train of an internal combustion engine, comprising an outer lever and an inner lever extending between the arms of this outer lever. Both levers can pivot relative to each other and one of the levers has on its bottom side a contact area for a head of a support element. In the region of this contact area there runs a longitudinal recess for a coupling means, which can be brought into engagement in some sections with a driving area on an end side of the other lever when the levers are coupled. At least one contact area for a large lift cam is applied to an upper side of the finger lever.
Such a finger levers emerge from U.S. Pat. No. 5,544,626 which is considered as a class-forming patent. This is described as a disconnecting lever, wherein when coupled, its coupling means viewed in the longitudinal direction of the lever can be displaced inwards under a driving area of a pivoting inner lever. The coupling means extends above a contact area for a support element in the outer lever. It is to be recognized that in the coupling area, flat engagement structures are provided. In addition, the coupling means are provided with a separate anti-rotation device.
Several disadvantages are inherent in the previously mentioned construction. The flattened section on the coupling means as well as the correspondingly flat driving area on the bottom side of the inner lever require unnecessary machining expense and thus increase the costs for mass production. In addition, it is clear that the separate anti-rotation device also has an unfavorable effect on the total costs of the previously mentioned finger lever. However, a particular disadvantage in the finger lever just cited is that due to the coupling elements with a fixed orientation, coupling is always realized at the same contact position. Thus, in the operation of the finger lever it is to be taken into account that grooves are formed in this fixed contact position little by little and it possibly also leads to undesired deformation or formation of indentations in this region.