| 摘要 |
PROBLEM TO BE SOLVED: To provide a jig for machining a cylinder block by which bolt axial force in tightening bolts in installation of a dummy-head is allowed to act efficiently as a bore load, and by the dummy-head installation, a bore deformation including heat-deformation under an actual engine-operation can be materialized, and improvement in roundness of the cylinder bore under an actual engine-operation can be achieved. SOLUTION: The dummy head 1 (cylinder-block-machining jig) includes a dummy-head body 10, which for finishing the cylinder bore 3 is installed by tightening the bolts on the head-installation surface 4 of the cylinder block 2, and this installation results in deformation of the bore 3. On the installation surface 11 of the dummy head 10 facing to the cylinder block 2, a protrusion 20 is provided which has a contact face 21 brought in contact to the periphery of the cylinder bore 3 in the head-installation surface 4. Thus, at least the dummy head body 10 is constituted to have higher rigidity than that of the cylinder bock 2. COPYRIGHT: (C)2008,JPO&INPIT
|
