Abstract: A rotation axis O2 of a shaft 3 is attached thereto with double-offset in the X and Y directions with respect to a center line O1 of a valve seat 2. A bevel process is implemented on the outer peripheral surface of a valve 1 such that the valve 1 and the valve seat 2 is line-sealed, and the sign of the angles of inclination is switched between plus and minus at two places of the outer peripheral surface of the valve 1 deviated from the center of the axis. Further, a section where the angle of inclination is constant is prepared in each of the sections connecting the two places, while the other sections are smoothly connected to each other.

Abstract: An exhaust gas recirculation valve includes an exhaust passage having an exhaust gas inlet and an exhaust gas outlet aligned on the same line, an EGR passage branched from the exhaust passage, a shaft attached rotatably at a branching point between the exhaust passage and the EGR passage, and an elliptically shaped butterfly valve rotating integrally with the shaft to open/close the exhaust passage and the EGR passage.

Abstract: A rotation axis O2 of a shaft 3 is attached thereto with double-offset in the X and Y directions with respect to a center line O1 of a valve seat 2. A bevel process is implemented on the outer peripheral surface of a valve 1 such that the valve 1 and the valve seat 2 is line-sealed, and the sign of the angles of inclination is switched between plus and minus at two places of the outer peripheral surface of the valve 1 deviated from the center of the axis. Further, a section where the angle of inclination is constant is prepared in each of the sections connecting the two places, while the other sections are smoothly connected to each other.

Abstract: A cache controller expresses a status of a data block by one of six statuses obtained by newly adding Writable Modified to Invalid, Shared, Exclusive, Modified, and Shared Modified. In response to a fetching request from a self system CPU for a data block having the status of Invalid I, when the data block having the status of Modified M is obtained from a cache apparatus of another system, the cache controller changes the status of the obtained data block from Invalid to Writable Modified. The cache controller also switches the status of the data block on the obtaining destination side from Modified to Invalid. As a result, the making of a status change notification to the other system in response to a subsequent storing request from the self system CPU, is unnecessary.