Claims:1. A high pressure fuel pump (10), said high pressure fuel pump (10) comprising:
10 a housing (12);
a plunger (14) positioned within said housing (12), said plunger (14) adapted
to reciprocate within said housing (12);
a vertical groove (16) defined in said plunger (14), said vertical groove (16)
adapted to extend along a sidewall of said plunger (14); characterized in that
15 a helix groove (18) in flow communication with the vertical groove (16) and
extending angularly along a sidewall of said plunger (14), the helix groove (18)
having a variable depth that extends across a width of the helix groove (18).
2. The high pressure fuel pump (10) in accordance with Claim 1, wherein a depth
of the helix groove (18) is lowest at a top end (19) of the helix groove (18) that
is proximate to a top (20) of said plunger (14), and wherein the depth of the
helix groove (18) is highest at a bottom end (21) of the helix groove (18) that
is farthest away from the top (20) of said plunger (14).
3. The high pressure fuel pump (10) in accordance with Claim 2, wherein the
helix groove (18) comprises a linear tapering edge (22) that extends from the
top end (19) of the helix groove (18) that is proximate to the top (20) of said
plunger (14) until the bottom end (21) of the helix groove (18) that is farthest
away from the top (20) of said plunger (14).
4. The high pressure fuel pump (10) in accordance with Claim 3, wherein the
linear tapering edge (22) of the helix groove (18) that extends from the top end
(19) of the helix groove (18) that is proximate to the top (5 20) of said plunger
(14) until the bottom end (21) of the helix groove (18) that is farthest away
from the top (20) of said plunger (14) has a constant tapering angle with
reference to an axis that is perpendicular to a longitudinal axis of said plunger
(14). , Description:A high pressure fuel pump 10 is described. The high pressure fuel pump 10 comprises
a housing 12, and a plunger 14 positioned within the housing 12. A vertical groove 16
is defined in the plunger 14 and adapted to extend along a sidewall of the plunger 14.
10 A helix groove 18 is in flow communication with the vertical groove 16 and extending
angularly along a sidewall of the plunger 14, the helix groove 18 having a variable
depth extending with a linear tapering edge 22 across a width of the helix groove 18.
The depth of the helix groove 18 is lowest at a top end 19 of the helix groove 18 that
is proximate to a top 20 of the plunger 14, and highest at a bottom end 21 of the helix
15 groove 18 that is farthest away from the top 20 of the plunger 14.