| 摘要 |
<p>The piston has a crown (10) including a band (11) in which piston ring grooves (12, 13, 14) are formed. A skirt (17) is joined integrally with the band, two projections (15) being formed integral with and extending from the crown and being spaced inwardly from the skirt (17). The projections form two gudgeon pin bosses with bores (16), the skirt having at least one aperture (18) for the insertion of the gudgeon pin. The piston also has an insert (20) with a lower coefficient of thermal expansion than the skirt, the insert having at least a part in contact with the skirt or with the band adjacent the skirt. The increase in diameter of the piston skirt in a plane at right angles to the gudgeon pin axis is reduced for a given temperature rise.</p> |
