The engine, as it cooled itself, sucked in air through the outlet hose, producing suction in the vacuum chamber, and so drawing the plunger down and compressing the spring.
当引擎冷却时，通过出口软管吸入空气，在真空管产生吸气，导致柱塞向下挤压弹簧。
2
Valve Disadvantages: the valve is prone to leakage around the stem, especially in-board leakage when a vacuum is pulled on the valve outlet.
阀门的缺点：当阀门排气口处是真空时，阀门在阀杆附近容易泄漏，特别是内部泄漏。
3
A vacuum adsorption nozzle is stuck on the center of the bottom surface of the metallic film of the flat plate, and a vacuum adsorption pipe is connected with an outlet of a vacuum adsorption device.