摘要 |
The air intake of an internal-combustion engine passes through a throttle whose upstream and downstream sides are shunted by an idle-speed circuit. A vacuum-actuated auxiliary device has a vacuum line connected to the downstream side of the throttle. An injector-type jet pump connected in the idle circuit has an outlet connected to the downstream side of the throttle, a high-pressure inlet connected to the upstream side of the throttle, and a low-pressure input connected to the vacuum line. This jet pump serves as a vacuum amplifier during low-speed engine operation to ensure sufficient vacuum to drive the auxiliary load. |