Patent ID: 7823558
Filing Date: 2010-11-02
Classification: F02B,F02M,Y02T

Abstract:
1. A tumble system for an intake manifold of an internal-combustion engine provided with a number of cylinders; the tumble system comprising: at least one throttle valve for varying the section of passage of the air through an intake pipe, which connects at least one cylinder with the intake manifold, and at least one actuator device for governing the throttle valve; wherein the actuator device comprises: at least one first actuator element, which is filiform, is wound in a spiral so as to assume the conformation of a spring, and is made of a shape-memory material that generates a displacement of activation of the throttle valve by modifying its own geometry following upon application of an external stress of a physical nature; at least one second actuator element, which is filiform, is wound in a spiral so as to assume the conformation of a spring, and is made of a shape-memory material that generates a displacement of activation of the throttle valve by modifying its own geometry following upon application of an external stress of a physical nature; and electric activating means for applying an external stress of a physical nature to the actuator elements; wherein the actuator elements are sized in such a way that, in the absence of external energizing, an actuator element prevails over the other actuator element.