Excuse me, the patent of ZL00 1282 14 has a time limit.

[Invention] Variable pressure exhaust pipe structure -00 1282 14. X

Date of application: 2000- 12- 12

The term of protection of an invention patent is 20 years, counting from the date of application. If the patentee keeps paying the annual fee, the patent will not expire in the future, and the protection period is 2020- 12- 12.