Fuel injector seal construction and method of manufacture

A fuel injector for an internal combustion engine, comprising:

• an injector body;
• a reciprocating injector jet needle in the injector body, supported by a tappet rod, an end of the tappet rod extending into an enclosure within the injector body, the enclosure surrounding one or more structures for enabling the supported reciprocating movement of the injector jet needle;
• and
• a fuel injector seal for providing a liquid-tight seal between the tappet rod and the enclosure, for precluding the intrusion of liquid fuel into the enclosure, the seal further comprising:
• a flexible bellows member, including an first cap sealingly joined to an second cap;
• the first cap including a first collar connected to one of the tappet rod of the fuel injector and the aperture into the enclosure through which the tappet rod of the fuel injector passes, the first cap further including a substantially radially extending flare and a second collar;
• the second cap including a first collar connected to the other of the aperture into the enclosure through which the tappet rod of the fuel injector passes and the tappet rod of the fuel injector, the second cap further including a substantially radially extending flare and a second collar;
• the second collar of the first cap being sealingly joined to the second collar of the second cap;
• the seal precluding intrusion of liquid fuel at the aperture of the enclosure.

A method for manufacturing a seal for a fuel injector for an internal combustion engine, wherein the fuel injector includes an injector body surrounding a reciprocating injector jet needle, supported by a tappet rod, an end of the tappet rod extending into an enclosure within the injector body, surrounding one or more structures for enabling the supported reciprocating movement of the injector jet needle, for providing a liquid-tight seal between the tappet rod and the enclosure, for precluding the intrusion of liquid fuel into the enclosure, the method for manufacturing a seal for a fuel injector for an internal combustion engine comprising:

• forming a flexible bellows member, including a first cap sealingly joined to a second cap;
• forming the first cap to include a first collar for connection to one of a tappet rod of a fuel injector and regions proximate an aperture into an enclosure through which a tappet rod of a fuel injector passes, the first cap further including a substantially radially extending flare and a second collar;
• forming the second cap to include a first collar for connection to the other of regions proximate an aperture into an enclosure through which a tappet rod of a fuel injector passes and a tappet rod of a fuel injector, the second cap further including a substantially radially extending flare and a second collar;
• sealingly joining the second collar of the first cap to the second collar of the second cap;
• whereupon installation of the seal into a fuel injector, the seal precludes intrusion of liquid fuel at the aperture of the enclosure.