Air intake channel system for internal combustion engines

#The invention relates to an air intake channel system for internal combustion engines, particularly for V engines.

#From DE 197 56 332, an air intake channel system is known where the length of several air intake channels each of which is connectable to a cylinder of an internal combustion engine is adapted to be continuously varied. To this end, the spirally configured intake channels are arranged next to each other. Each spiral air intake channel comprises an air inlet opening connected to a central inner region of the air intake system. Through said air inlet opening, air enters into the spiral channel and is led to the respective cylinder after it has flown through the spiral channel. Within the central region, a tubular channel member is arranged which forms the inner wall of the spiral channel and comprises the air inlet opening. The tubular channel member is pivotably arranged so that the position of the air entrance opening can be varied. By pivoting the tubular channel member, the length of the air intake channel, i.e., the distance between the air entrance opening and the air exit opening to be flown through by the air, can thus be continuously varied.

#The individual channel members forming the intake channels are arranged adjacent to each other or stacked upon each other, the configured air intake channels being alternately connected with the one or the other row of the cylinders of the V engine. For pivoting the inner pivotable channel members, they are connected to a pivot axis. Thus, each air intake channel is formed substantially by a stationary channel member and a pivotable channel member. The tubular pivotable channel member is supported in a recess of the stationary channel member. Since the cross-section of the individual air intake channels has to be relatively large to provide a sufficient amount of air, such air intake channel systems with variable lengths of the air intake channels are built very large, particularly in six or eight cylinder engines.

#Hereinafter, the invention is explained in detail with respect to a preferred embodiment thereof with reference to the accompanying drawings, in which:

#FIG. 1 shows a schematic sectional view of an air intake channel system for an eight cylinder V engine according to prior art,

#FIG. 2 shows a schematic sectional view of an air intake channel unit according to the invention in a first position,

#The air intake channel system according to prior art illustrated in FIG. 1 comprises eight spirally extending air intake channels 10,12. The intake channels 10 are connected to one side of the V engine via lugs 14 and the intake channels 12 are connected to the other side of the V engine via lugs 16. Each of the individual intake channels is formed by a first channel member 18 that is stationary in the illustrated embodiment and a second channel member 20,22 that is adapted to be pivoted. Except for the two channel members provided at the left and right border in the Figure, all the first channel members 18 have an identical structure and are arranged next to each other or stacked upon each other, as illustrated in FIG. 1. The first channel members 18 are arranged in a housing 24 comprising two housing halves. The pivotable second channel members 20 and 22 are identically formed as well.

#The air to be supplied to the individual intake channels 10,12 is led via an air intake fitting 26 in the direction of an arrow 28 into the common inner region 29 of the air intake system. The inner region 29 is formed by the pivotable channel members 20,22 arranged next to each other each of which has a substantially circular cylindrical configuration. Depending on the design, additional intake openings are connected to the individual air intake channels 10,12, if necessary, so that air enters into the air intake channels 10,12 through the central region of the air intake channel system as well as through the additional supply channels. From the central region of the air intake channel system, the air enters through the air inlet openings provided in the pivotable channel members 20,22 into the corresponding air intake channels 10,12. Therefrom, the air exits through air outlet openings 30 and 32, respectively, and is guided to the corresponding cylinders through non-illustrated channels.

#For varying the length of the air intake channels 10,12, the pivotable channel members 20,22 are firmly connected with pivot axes 34,36. By pivoting the pivot axes 34,36 by means of an actuator 38, the air inlet openings of the pivotable channel members 20,22 are changed in their positions so that the air from the central region 29 enters into the spiral air intake channels 10,12 at another position and thus has to cover a shorter or longer distance.