Pressure curve of nozzle volume and control chamber can objectively reflect the injection process in electronically controlled solenoid common-rail system. Measurement can accurately provide the boundary conditions for design of injector and fluid calculation. The response times of solenoid, opening and closing delay of needle, and real injection duration can be obtained with analysis of pressure curves. Control chamber and nozzle volume pressures are equal to common-rail pressure in the case of no injection. Pressure accompanies large fluctuations and the pressure of nozzle volume is higher than the pressure of control chamber during injection process. Pressure fluctuations still exist when needle is closed, and this will affect the follow-up injection in multi-injection process. Pressure drop of control chamber and nozzle volume relate to the rail pressure. Maximum pressure drop of 20% in nozzle volume is presented at the start of injection. Control chamber pressure decreases by 54% at maximum valve lift. Pressure difference between control chamber and nozzle volume keeps 43% of rail pressure at maximum valve lift.%控制腔和盛油槽压力的联合测量结果客观地反映了喷油器工作过程中盛油槽和控制腔的压力变化情况,测量结果将为该喷油器零部件设计计算提供准确的边界.通过盛油槽和控制腔的压力变化过程分析,可以得到电磁铁的响应时间、针阀的开启和关闭延迟以及实际的喷油持续期等喷油参数.在不喷油的时候控制腔和盛油槽压力与轨压相同,在喷油过程中控制腔和盛油槽均存在较大的压力波动,但控制腔压力始终低于盛油槽压力.在喷油结束后,控制腔和盛油槽压力仍存在波动,该压力波动将影响多次喷射的后喷射.盛油槽和控制腔压力下降的幅值与轨压有关,但盛油槽压力下降的最大幅度为轨压的20％,控制腔压力下降的最大幅度在针阀最大升程时保持不变为轨压的54％,盛油槽与控制腔的压力差在最大针阀升程下保持不变为轨压的43％.
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