| 摘要 |
<p>: An idle speed control device for an automobile engine has an electromagnetic driving portion and a flow rate controlling portion disposed in a bypass passage formed in a throttle chamber so as to bypass a throttle valve. The flow rate controlling portion has a body defining a passage for the air to be controlled, a seal formed in an intermediate portion of the passage, a first valve driven by a plunger of the electromagnetic driving portion through a rod so as to be brought into and out of contact with the seat. A sleeve is disposed in the body, and a second valve is connected through the rod to the downstream side of the first valve so as to produce a vacuum force that acts in the opposite direction to the vacuum force produced on the first valve whereby to absorb any fluctuation in the intake pressure in cooperation with the first valve. The second valve is loosely received in the sleeve. By this arrangement, it is possible to eliminate any unfavourable effect of the fluctuation in the intake vacuum on the actual air flow rate. In addition, since the flow from the vacuum compensating portion is minimized, vacuum compensation is made possible without incurring any increase in the initial leak.</p> |
