Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
158 words
A fuel injector comprising a nozzle body (10) defining a bore (11)
within which an outer valve member (12) is slidable, the outer valve member
(12) being engageable with a first seating (14) to control fuel injection from a
first outlet opening (18) provided in a nozzle body (10), the outer valve
member (12) being provided with a through bore (19) within which an inner
valve member (20) is slidable, the inner valve member (20) being engageable
with a second seating (26) to control fuel injection through a second outlet
opening (28) provided in the nozzle body (10), the fuel injector further
comprising first and second control chambers (56, 80) for fuel, whereby, in use,
movement of the inner and outer valve members (20, 12) away from their
respective seatings (26, 14) is controlled by controlling fuel pressure within the
first and second control chambers (56, 80) so as to permit fuel delivery from a
selected outlet opening.
Claim 2
Dependent Claim
21 words
The fuel injector as claimed in Claim 1, wherein the second seating (26)
is defined by the outer valve member (12).
Claim 3
Dependent Claim
66 words
The fuel injector as claimed in Claim 1 or Claim 2, the inner valve
member (20) and the outer valve member (12) being arranged to have a first
fuel injecting position in which the inner valve member (20) is lifted away
from the second seating (26) whilst the outer valve member (12) remains seated
so that fuel injection occurs only through the second outlet opening (28).
Claim 4
Dependent Claim
99 words
The fuel injector as claimed in Claim 3, the outer valve member (12)
and the inner valve needle (20) being arranged to have a second fuel injecting
position in which the outer valve member (12) is lifted away from the first
seating (14) to permit fuel injection through the first outlet opening (18), a
force due to movement of the outer valve member (12) being transmitted to the
inner valve member (20) to move the inner valve member (20) with the outer
valve member (12) such that the inner valve member (20) remains seated
against the second seating (26).
Claim 5
Dependent Claim
34 words
The fuel injector as claimed in Claim 4, comprising a sac region (27)
into which fuel flows, in use, when the inner and outer valve members (12, 20)
adopt their second fuel injecting position.
Claim 6
Dependent Claim
37 words
The fuel injector as claimed in any of Claims 1 to 5, wherein the outer
valve member (12) is provided with an opening (42, 44) to permit fuel to flow
into the through bore (19), in use.
Claim 7
Dependent Claim
48 words
The fuel injector as claimed in any of Claims 1 to 6, wherein the outer
valve member (12) includes first and second valve parts (12b, 12a), the first
valve part (12b) being engageable with the first seating (14) to control fuel
flow through the first outlet opening (18).
Claim 8
Dependent Claim
26 words
The fuel injector as claimed in Claim 7, wherein the first and second
valve parts (12b, 12a) of the outer valve member (12) are integrally formed.
Claim 9
Dependent Claim
31 words
The fuel injector as claimed in Claim 7 or Claim 8, wherein the first and
second valve parts (12a, 12b) together define a chamber (30) for housing a
sealing member (34).
Claim 10
Dependent Claim
23 words
The fuel injector as claimed in Claim 9, further comprising means (32)
for biasing the sealing member (34) against a sealing seating (36).
Claim 11
Dependent Claim
51 words
The fuel injector as claimed in any of Claims 1 to 10, wherein the first
control chamber (56) is defined within the bore (11) provided in the nozzle
body (10), fuel pressure within the first control chamber (56) serving to urge
the outer valve member (12) against the first seating (14).
Claim 12
Dependent Claim
37 words
The fuel injector as claimed in any of Claims 1 to 11, the second control
chamber (80) being arranged such that fuel pressure therein serves to urge the
inner valve member (20) against the second seating (28).
Claim 13
Dependent Claim
54 words
The fuel injector as claimed in Claim 12, comprising a piston member
(70), a surface of which is exposed to fuel pressure within the second control
chamber (80), the piston member (70) being arranged to transmit a force due to
fuel pressure within the second control chamber (80) to the inner valve member
(20).
Claim 14
Dependent Claim
44 words
The fuel injector as claimed in any of Claims 1 to 13, comprising a first
control valve arrangement for controlling fuel pressure within the first control
chamber (56) and a second control valve arrangement for controlling fuel
pressure within the second control chamber (80).
Claim 15
Dependent Claim
33 words
The fuel injector as claimed in any of Claims 1 to 14, comprising a
common control valve arrangement arranged to control fuel pressure within
both the first and second control chambers (56, 80).