Common motor driven dual butterfly valves

A valve having a housing in which three ducts that are connected to each another are arranged, one flap, which is mounted rotatably on a shaft is arranged in each of two ducts, an electric motor which drives a shaft by a gearing system, and a transmission mechanism, which drives the second flap depending on the movement of the first flap. On the shaft of the first flap, a cam disc is arranged, on the circumference of which a lever rests, which is connected in a rotationally fixed manner to the shaft of the second flap.

CROSS REFERENCE TO RELATED APPLICATIONS

This is a U.S. national stage of application No. PCT/EP2013/076227, filed on Dec. 11, 2013. Priority is claimed on German Application No. DE102012224232.5, filed Dec. 21, 2012, the content of which is incorporated here by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject matter of the invention is a three-way valve having a housing, in which three ducts that are connected to one another are arranged having one flap that is mounted rotatably on a shaft is arranged in each of two ducts, an electric motor that drives a shaft via a gear mechanism, and a transmission mechanism that drives the second flap depending on the movement of the first flap.

2. Detailed Description of the Prior Art

Housings of this type are used as air and exhaust gas valves in motor vehicles and are therefore known. Gas streams flow through the ducts with the flaps, which gas streams are to be fed to the third duct individually or in a mixed manner in certain conditions depending on the situation. This means that the rotational angle of the first flap is assigned a certain rotational angle of the second flap. Accordingly, the rotational angle of the first flap corresponds to a certain operating situation, to which the rotational angle of the second flap has to be adapted. The adaptation of the rotational angle of the first flap to the corresponding operating situation is realized by the actuation of an electric motor. The corresponding adjustment of the second flap by a transmission mechanism. To this end, it is known to arrange a disk which has a closed slot on the shaft, on which the first flap is fastened. A cam is arranged in said slot, which cam moves in said slot during a rotation of the disk. The movement of said cam is transmitted to the shaft of the second flap. The slot corresponds to a control cam in the manner of a slotted guide, and the cam corresponds to the sliding block. A disadvantage of this configuration is that, as a result of the slot being arranged completely within the circumference of the disk, said disk can have very large external dimensions, as a result of which the valve requires a large amount of installation space.

SUMMARY OF THE INVENTION

An object of the invention is providing a valve that requires less installation space, which is achieved with a cam disk arranged on the shaft of the first flap, a lever that bears against the circumference of the cam disk, and that the lever is connected fixedly to the shaft of the second flap to rotate with it.

During the rotation of the cam disk and therefore of the first flap, the lever and therefore the shaft of the second flap are moved depending on the rotation of the first flap. Here, any desired movement profiles can be reproduced via the cam disk. Since said movement profiles can be stored on the circumference of the cam disk, the cam disk can be of relatively small design. In this way, the valve according to the invention requires a relatively small amount of installation space in the region of the transmission mechanism. Said valve also has less wear on due to the lower friction in the transmission mechanism. In addition, said valve does not require a coupling between the shafts.

In one advantageous refinement, the low-friction transmission of the movement profile is achieved by a rotatable roller arranged at that end of the lever that faces the cam disk.

The arrangement of the roller requires a particularly small additional amount of installation space if the roller is a needle bearing.

To ensure the constant contact between the lever or the roller and the cam disk, a spring presses the lever against the cam disk.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

As shown in the FIGURE valve has a housing1, in which three ducts2-4are arranged. Gas streams can flow via the two horizontal ducts2,3into the duct4. The shaft5and therefore the first flap6are driven via an electric motor20(shown structurally). A cam disk7is fastened on the shaft5, the circumference of which cam disk7defines the pivoting angle of the second flap11. To this end, a needle bearing8traverses the circumference of the cam disk7. The needle bearing8is fastened to a lever9, and the latter is connected fixedly to the shaft10of the second flap11so as to rotate with it. The lever9is pressed against the cam disk7via a spring12, which is supported on a housing-side stop13.