US 11,939,941 B2
Gasoline direct injection fuel pump with isolated plunger sleeve
Joseph G. Spakowski, Rochester, NY (US)
Assigned to DELPHI TECHNOLOGIES IP LIMITED, St. Michael (BB)
Filed by DELPHI TECHNOLOGIES IP LIMITED, St. Michael (BB)
Filed on Mar. 24, 2022, as Appl. No. 17/703,170.
Prior Publication US 2023/0304462 A1, Sep. 28, 2023
Int. Cl. F02M 59/02 (2006.01); F02M 59/10 (2006.01); F04B 1/0439 (2020.01); F04B 19/22 (2006.01); F04B 53/04 (2006.01); F04B 53/16 (2006.01); F04B 1/0408 (2020.01); F04B 1/0421 (2020.01); F04B 11/00 (2006.01)
CPC F02M 59/025 (2013.01) [F02M 59/102 (2013.01); F04B 1/0439 (2013.01); F04B 19/22 (2013.01); F04B 53/04 (2013.01); F04B 53/168 (2013.01); F04B 1/0408 (2013.01); F04B 1/0421 (2013.01); F04B 11/0033 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A fuel pump comprising:
a pump body defining a central bore and a pumping chamber therein;
a plunger, moveable within the central bore of the pump body, the plunger being mechanically actuated for compressing fuel within the pumping chamber; and
a sleeve within the central bore and surrounding the plunger along a lengthwise portion thereof, the sleeve including a cylindrical sidewall and upper and lower guide ribs, the upper and lower guide ribs being outwardly convex and circumferentially disposed about an exterior of the sleeve and being spaced apart from each other, the upper and lower guide ribs being integrally formed with the cylindrical sidewall, the sleeve and the pump body being formed from metal such that an upper axial surface of the sleeve abuts the pump body creating a metal-on-metal sealing interface;
wherein an outer diameter of the plunger and an inner diameter of the sleeve define a first diametral clearance, and wherein an outer diameter of the upper and lower guide ribs and an inner diameter of the central bore define a second diametral clearance, the second diametral clearance being at least 75% of the first diametral clearance to accommodate thermal expansion of the sleeve;
wherein the pump body further defines a drain port in fluid communication with the central bore, such that fuel diverting around the upper guide rib during pumping operations can recirculate through the drain port to a low-pressure portion of the pump body;
wherein the upper and lower guide ribs are separated by an intermediate portion of the sleeve, the intermediate portion defining an outer diameter less than the outer diameter of the upper and lower guide ribs.