| 摘要 |
<p>A fluid injector, for example for injecting liquid fuel into a combustion chamber, comprises a valve housing and an injector assembly removably mounted on the valve housing. The injector assembly includes discharging means for discharging fluid from the injector assembly, ducting for conveying the fluid between the valve housing and the discharging means and a control valve movable to a first position in response to flow of the fluid in a first direction through the ducting to close the discharging means and return the fluid from the discharging means to the valve housing and movable to a second position in response to flow of the fluid in a second direction through the ducting to open the discharging means to allow at least some of the fluid conveyed to the discharging means to be discharged therefrom and to return any surplus fluid to the valve housing. Provided in the valve housing are inlet and outlet passages for conveying the fluid into and from the valve housing, and a change-over valve. The change-over valve comprises a valve member adjustable into a first position to condition the injector for flow of the fluid from the inlet passage through the ducting in said first direction and into a second position to condition the injector for flow of the fluid from the inlet passage through the ducting in said second direction. A control means for the change-over valve is actuable to move the valve member into a third position in which the change-over valve prevents the flow of fluid from the inlet passage to the ducting. This control means comprises a mechanical interlock preventing removal of the injector assembly from the valve housing unless the valve member has been moved into its third position by the control means.</p> |
