| 摘要 |
<p>A sleeve for engine cylinder head includes two symmetrical pieces (10) with inner walls that are smooth surfaces, wherein two pieces (10) both have a circular arc section (11) and a projection section (12), and a recess (13) is formed on one side of the circular arc section (11), two pieces (10) are extended into an intake/exhaust duct (21) by the projection section (12) and sleeved on the intake/exhaust duct (21), uneven inner wall of the intake/exhaust duct (21) is replaced with inner smooth walls of two pieces (10) for reducing oil sludge deposition and making engine in good operation. If oil sludge deposition affects air input, air input can be maintained by changing the sleeve and controlled by the sleeve.</p> |
