Patent RU-2317437-C2 (RU)
IPC: F02M61/10
Filed: 2005-01-21
Granted: 2008-02-20
Abstract: FIELD: mechanical engineering; internal combustion engines. 
     SUBSTANCE: invention relates to fuel equipment of internal combustion engines operating mainly on low-viscosity fuels and fuel mixtures of different composition.  Proposed nozzle has body with device for fastening nozzle in cylinder head, overneedle space and threaded union projecting from cylinder head on internal combustion engine for connecting high-pressure fuel pipe from high-pressure pump.  Spray tip with nozzle orifices is connected with body by spray tip nut.  Needle with shank, differential flat and shutoff cone is arranged in spray tip forming underneedle space communicating through channels in spray tip and body with union for connecting high-pressure fuel pipe at one side, and with nozzle orifices at other side.  Spindle arranged in body engages by first end with needle shank, and by second end, lower flange of spring.  Upper flange of spring is made for engagement with adjusting nut in nozzle body.  Spray tip nut is made of material whose thermal conductivity is higher than that of steel.  Gasket for sealing nozzle in cylinder head hole is made in form of central gasket made of low-carbon steel arranged between two gaskets made of titanium alloy.  Two disk springs are installed between end face parts of spray tip nut and device fastening nozzle to cylinder head.  Spindle centering bushing is arranged in overneedle space of body.  Shank of needle is made for engagement with first end of spindle through pair of spherical surfaces made on end faces of shank and first end of spindle.  Upper and lower flanges of spring are made for engagement with adjusting nut and second end of spindle, respectively, thorough pair of spherical surfaces made on end faces of upper and lower flanges of adjusting nut and first end of spindle.  Ring grooves made in spray tip and on side surface of needle provide periodical communication of over needle space with ring groove of needle through calibrated stepped channel in body.  Threaded union projecting from cylinder head and designed for connecting high-pressure fuel pipe from high-pressure fuel pump is made in from of outer and inner pipes arranged coaxially relative to each other.  Outer pipe is connected by its first end through first rubber gasket and thread with body, and by second end part through second rubber gasket, washer, first nut and first locknut it is hermetically connected with outer surface of cylinder head.  External projections in contact with inner surface of outer pipe are made on outer surface of inner pipe.  End face surface of outer projection made of first end of inner pipe presses shutoff cone of high-pressure fuel pipe arranged in space of inner pipe to body, thus providing hermetic connection of high-pressure pipe with channel in body.  Second nut is installed on thread from end face of second end of outer pipe to engage with second end of inner pipe and provide pressing of inner pipe to high-pressure fuel pipe by means of second locknut. 
     EFFECT: improved reliability and increased service life of nozzle, provision of stability of fuel injection and facilitated operation and maintenance of internal combustion engines. 
     4 cl, 3 dwg