| 摘要 |
<p>ELECTROMAGNETIC UNIT FUEL INJECTOR WITH DIFFERENTIAL VALVE An electromagnetic unit injector for use in a diesel engine includes a housing with a pump therein defined by an externally actuated plunger reciprocable in a bushing to define therewith a pump chamber open at one end for the discharge of fuel via a discharge passage means to a spring biased, pressure actuated injection nozzle. The pump chamber is supplied with fuel from a fuel chamber, containing fuel at a suitable supply pressure, via a one-way valve controlled supply passage. The discharge passage means is also in flow communication with the fuel chamber via a primary drain passage means as controlled by a differential area valve. The differential area valve, at an enlarged diameter end thereof defines, in part, a pressure control valve that is connected by a throttle orifice passage to fuel flow in the discharge passage means and, by a secondary drain passage, having a solenoid actuated control valve therein, to the fuel chamber.</p> |
