求翻译：主要用于直接喷射式燃烧室中，它由针阀体和针阀组成，喷孔数目l一8个，最多可达10个，孔径0.15-1.0mm。喷孔数目与方向决定于不同燃烧室对喷雾质量的要求以及喷油器在燃烧室内的布置。喷油嘴针阀的上面压有弹簧，使针阀紧压在针阀体座面上，当喷油泵输送的高压油作用在锥面上时，才能使针阀抬起开始喷射。是什么意思？

Mainly for direct injection combustion chamber, is made up of needle valve and needle valves, orifice number l 18, maximum of 10, aperture 0.15-1.0mm. Orifice number and direction is decided to different combustion chamber on spray quality requirements as well as the placement of injectors in the co

正在翻译