Structure of cylinder block being cast with cylinder liner, method of manufacturing cylinder block, and cylinder liner to be cast in the method of manufacturing cylinder block
View Patent ↗A cylinder block has a cast cylinder liner. A different level portion with a predetermined width is provided in a projected part formed along the lower end-face of the cylinder liner, in the centrifugal direction of the cylinder liner. In this case, the different level portion has a width corresponding to the dimensional tolerance range with respect to a finished inside diameter dimension position, and a outer circumference edge of the different level portion is provided in the outer circumference side farther than the finished inside diameter dimension position. Displacement of a hole is detected by checking the different level portion after machining the internal circumference of the cylinder liner.
1. A method of manufacturing a cylinder block by casting a cylindrical cylinder liner at a predetermined position, the cylinder liner having an outer wall and an inner wall comprising:
preparing a cylinder liner as a primary product having an end wall and an annular different level portion axially inward of the end wall with a boundary formed inward in the radial direction by a predetermined dimension with respect to a finished dimension of an internal circumference of the inner wall of the cylinder liner;
fixing the cylinder liner as a primary product to a holding part that is provided in a mold to form the cylinder block, the mold having a portion fitting with the different level portion;
casting the cylinder block by filling the mold with molten metal;
machining the inner wall of the cylinder liner to the finished dimension; and
detecting whether the different level portion still exists after the machining step to determine at least one of a position of the cylinder liner relative to the cylinder block, a position of the inner wall of the cylinder liner relative to the outer wall of the cylinder liner, and a thickness of the cylinder liner between the cylinder liner inner wall and the cylinder liner outer wall.
2. A method of manufacturing a cylinder block comprising:
providing a cylinder liner having an inner wall and an outer wall and an annular end face having an radially inner annular portion and a radially outer annular portion;
providing a cylinder block mold including a holding portion for holding the cylinder liner during a casting process;
placing the cylinder liner in the mold on the holding portion so that the holding portion engages the radially inner portion of the annular end face of the cylinder liner;
filling the mold with molten metal so that the metal fills a space between the radially outer annular portion of the cylinder liner and the holding portion to form a different level portion in the cylinder block at the end face of the cylinder liner;
finish machining the inner wall of the cylinder liner after casting to remove at least part of the different level portion; and
detecting whether portions of the different level portion still exist after the finish machining step to determine at least one of a displacement of the cylinder liner from the cylinder block, a displacement of the machining position of the inner wall of the cylinder liner relative to the outer wall of the cylinder liner, and a thickness of the cylinder liner between the inner wall and the outer wall.