| 摘要 |
<p>771,692. Valves. GENERAL MOTORS, Ltd. May 6, 1955 [June 8, 1954], No. 16708/54. Class 135. The radiator cap of an I.C. engine has a main spring-loaded relief valve comprising a rubber-sealing ring 19 held between a member 14 mounted on a stud 8 and a member 17 pressed into the member 14, and a secondary valve consisting of a rubber disc 21 adapted to move freely in the space between the members. When the cooling liquid vaporizes the disc is lifted and allows the vapour to escape through the apertures 23, 24 of the member 17 and the holes 15 in the member 14 until the disc closes on the shoulder 13 of the member 14. The pressure in the radiator then builds up until it lifts the sealing ring 19 from its seating. When the radiator cools, the disc returns to its original position and air passes through the holes 15 and the apertures 24 into the radiator, thus preventing the formation of a vacuum therein. Specification 511,007 is referred to.</p> |
