1. Field of the Invention
The invention generally relates to an electromagnetically driven valve. More specifically, one embodiment relates to a pivot-type electromagnetically driven valve for an internal combustion engine, which is driven by an elastic force and an electromagnetic force. The invention may be used, for example, in the field of electromagnetically driven valves for an internal combustion engine that is provided for a vehicle.
2. Description of the Related Art
U.S. Pat. No. 6,467,441 describes a pivot-type electromagnetically driven valve that includes two coils. In the electromagnetically driven valve, a supporting point is provided in a disc (armature). In conventional electromagnetically driven valves, a large gap exists between a disc and an electromagnet and a small electromagnetic force is provided at an end portion. As a result of this arrangement, it is difficult to obtain a large initial driving force. Further, it is necessary to increase the amount of electric current to obtain the large initial driving force. But increasing the amount of electric current necessarily increases the amount of consumed electric power.