Patent ID: 7171866

Claim:
A vibration generator comprising: a first unbalanced shaft and a second unbalanced shaft which is axially parallel to the first unbalanced shaft and which is coupled thereto by a form-locking coupling such that the first and second unbalanced shafts can rotate in opposite directions, one of the unbalanced shafts being driven to rotate; and a phase changing device which is integrated in the form-locking coupling between the first and second unbalanced shafts for the purpose of adjusting a relative phase position of the first and second unbalanced shafts; wherein each of the first and second unbalanced shafts bears a main unbalanced mass and a part unbalanced mass which moves with respect to the main unbalanced mass; a first adjusting device is provided for actively adjusting phase position between the main unbalanced mass and the part unbalanced mass on the first unbalanced shaft; wherein a second adjusting device is provided for actively adjusting a phase position between the main unbalanced mass and the part unbalanced mass of the second unbalanced shaft; the first adjusting device and the phase changing device are supplied with energy from an external source and are each controlled by a separate control, and the second adjusting device is coupled to one of the phase changing device and to a combination of the first adjusting device and the phase changing device in such a manner that it is controlled exclusively by way of the effect of the phase changing device or the combination of first adjusting device and the phase changing device; wherein the second unbalanced shaft and the main unbalanced mass on the second unbalanced shaft are fixedly connected to each other; and wherein the second adjusting device is coupled to the phase changing device in a form-locking manner such that an adjustment, caused by the phase changing device, of the phase position of the first unbalanced shaft causes a similar adjustment of the phase position of the part unbalanced mass on the second unbalanced shaft.