Abstract

A plunger device comprises a main body (1), a first plunger (2), a second plunger (3) and a driving assembly (4). The main body has a plunger hole, a a fluid inlet (5), a fluid outlet (6) and a lubricant inlet (7). Each of the first plunger and the second plunger is slidably engaged at the plunger hole. A fluid receptacle (8) is formed between a first end of the first plunger and an inner wall of the plunger hole. A lubricant receptacle (9) is bounded by a second end of the first plunger, a first end of the second plunger and the inner wall of the plunder hole. Also provided is an internal combustion engine. The plunger device and the internal combustion engine can reduce leakage and abrasion of parts upon pumping fuel.

IPC Classes  ?

• F02M 59/02 - Pumps specially adapted for fuel-injection and not provided for in groups of reciprocating-piston type
• F02M 59/10 - Pumps specially adapted for fuel-injection and not provided for in groups of reciprocating-piston type characterised by the piston drive

Abstract

A plunger fuel injector, comprising: a body (1), wherein the body (1) is provided with a plunger hole, an inlet (5) of a fluid to be injected, an injection opening (6), and a lubricating oil inlet (7); a lower plunger (2) slidably fitted in the plunger hole, wherein the lower end of the lower plunger (2) is configured to open or close the injection opening (6); an injection chamber (8) formed between the lower end of the lower plunger (2) and the inner wall of the plunger hole, wherein said inlet (5) and the injection opening (6) are both configured to be in communication with the injection chamber (8); an upper plunger (3) slidably fitted in the plunger hole; a lubricating oil chamber (9) formed between the lower end of the upper plunger (3), the upper end of the lower plunger (2), and the inner wall of the plunger hole; a first one-way valve (10), wherein the lubricating oil inlet (7) is configured to be in communication with the lubricating oil chamber (9) by means of the first one-way valve (10); and a first resetting device (4) configured to provide a force to the upper plunger (3) for moving downwards. Also provided is an internal combustion engine comprising the plunger fuel injector. The plunger fuel injector and the internal combustion engine can reduce the problem of leakage while increasing injection pressure.

IPC Classes  ?

• F02M 47/04 - Fuel-injection apparatus operated cyclically with fuel-injection valves actuated by fluid pressure using fluid, other than fuel, for injection-valve actuation
• F02M 61/10 - Other injectors with elongated valve bodies, i.e. of needle-valve type