| 摘要 |
PURPOSE:To permit an intake throttle valve to be always controlled automatically to a desired valve opening degree by controlling an intake throttling amount in the range of half opening of an intake throttle valve in idling by an actuator equipped with a two-stage diaphragm in use of intake netative-pressure. CONSTITUTION:An intake throttle apparatus is constituted of a main intake throttle valve 11 which is interlocked with the steping-in of an accelerator pedal through a wire 15 and is perfectly opened in idling and a sub-intake throttle valve 12 for controlling the intake throttle amount during idling. While, the sub- intake throttle valve 12 is constituted of diaphragms 22 and 42 which are installed in two shells 20 and 40 installed back to back through a seal 26, and an atomospheric-pressure chamber 24 and negative-pressure chambers 23, 43 and 45 are formed in partition inside. The negative-pressure chambers 23 and 45 are allowed to communicate each other and connected to a negative-pressure source 34 through a bimetal vacuum switch valve 31, throttle 32, and a highly compensating apparatus 33, and the negative-pressure chamber 43 is connected to an intake negative-pressure port 18 through a vacuum switching valve 50. |
