GB2034812A - Fuel injection nozzles - Google Patents
Fuel injection nozzles Download PDFInfo
- Publication number
- GB2034812A GB2034812A GB7932882A GB7932882A GB2034812A GB 2034812 A GB2034812 A GB 2034812A GB 7932882 A GB7932882 A GB 7932882A GB 7932882 A GB7932882 A GB 7932882A GB 2034812 A GB2034812 A GB 2034812A
- Authority
- GB
- United Kingdom
- Prior art keywords
- fuel
- body part
- valve assembly
- annular
- nozzle
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
- F02M61/04—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00 having valves, e.g. having a plurality of valves in series
- F02M61/08—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00 having valves, e.g. having a plurality of valves in series the valves opening in direction of fuel flow
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M61/00—Fuel-injectors not provided for in groups F02M39/00 - F02M57/00 or F02M67/00
- F02M61/16—Details not provided for in, or of interest apart from, the apparatus of groups F02M61/02 - F02M61/14
Abstract
A nozzle 12 includes a valve assembly 19 located within a chamber defined in a body part 15, 16 to which fuel is supplied through an inlet 21. The wall 17 of the chamber is resilient whereby during the initial delivery of fuel to the injection nozzle the wall deflects to store fuel whereby the initial rate of flow of fuel to the engine will be reduced. The valve (26), Fig. 2 (not shown), in the assembly 19 is of the outwardly opening type. <IMAGE>
Description
SPECIFICATION
Fuel injection nozzles
This invention relates to fuel injection nozzles for supplying fuel to compression ignition internal combustion engines and of the kind comprising a hollow body part, a valve assembly including a resiliently loaded valve member and a seating, the valve assembly being located within the body part with a valve head forming part of the assembly being exposed at or beyond one end of the body part, and a fuel inlet communicating with the interior of the body part, the arrangement being such that in use, when fuel under pressure is supplied to the inlet, the fuel pressure within the body part acting upon the components of the valve assembly will effect movement of the valve head away from the body and the seating to permit fuel to flow past the valve head and seating into in use, the respective combustion chamber of the associated engine.
In use, the nozzle is secured within a bore in the cylinder head of an engine so that fuel flowing past the valve head and seating is atomised and is injected directly into the combustion space of the engine. The fuel is supplied by an injection pump which operates in timed relationship with the engine and which may supply fuel to other nozzles of the engine. The rate of fuel flow to the engine during the period of fuel delivery has a bearing on the amount of noxious gas in the engine exhaust and it has been found that the rate of flow of fuel through the nozzle should increase relatively slowly at the start of injection and decrease as rapidly as possible at the end of injection.
It is known to incorporate various types of device in'the fuel conveying conduit between the pump and the nozzle or even within the nozzle, which act to provide the desired initial rate of fuel flow. These devices are however, complex and therefore costly and generally comprise some form of valve which limits the initial flow rate by providing temporary storage for some of the fuel flowing from the pump. Since the type of nozzle set out in the first paragraph is well known as being a comparatively cheap form of nozzle as compared with the more conventional form of nozzle in which the valve member moves in a direction away from said one end of the body part it is not appropriate to have to provide an expensive valve to control the rate of fuel flow.
The object of the invention is to provide a nozzle of the kind specified in a simple and convenient form.
According to the invention a nozzle of the kind specified includes an annular elongated part located within the body part, said elongated part surrounding the portion of the valve assembly lying within the body part, said elongated part acting to define part of the wall of a chamber to which fuel under pressure is supplied from the inlet and from which fuel flows when the head is moved out of contact with the seating, the wall thickness of said elongated part being such that the wall deflects during the initial delivery of fuel to the nozzle thereby to store part of the initial flow of fuel whereby the initial rate of flow of fuel past the valve head and seating will be at a reduced rate.
According to the further feature of the invention said annular elongated part defines an annular space with the surrounding body part, said space in use being substantially at atmospheric pressure.
In the accompanying drawings.
Figure 1 shows a diagram of a fuel system incorporating a nozzle in accordance with the invention,
Figure 2 shows to an enlarged scale, the valve assembly of the nozzle,
Figures 3, 4 and 5 are sectional side elevations showing various forms of the nozzle.
Referring to Figure 1 of the drawings an engine fuel system includes a pump 10 which in use is driven in timed relationship with the associated engine. The pump is provided with a plurality of outlets indicated at 1 and each of these outlets is connected to a respective injection nozzle one of which is indicated at 12, by means of a fuel supply line 13. The nozzle 12 in use, is located within a bore formed in the cylinder head 14 of the engine so that the inner end of the nozzle projects into a combustion space of the engine.
Turning now to Figure 3 the nozzle 12 comprises a body part which is formed in two parts 15, 16. The part 1 6 is of hollow form and is provided with a peripheral screw thread for engagement in use, in the bore formed in the cylinder head of the engine. In addition, the part 1 6 is provided with a hexagonal portion for engagement by a spanner or the like to enable the nozzle to be tightened within the aforesaid bore.
The part 15 is provided with a hexagonal sectional intermediate its ends and on opposite sides of the hexagonal section, two sets of peripheral screw threads. The part 16 is internally threaded to receive one of the sets of screw threads on the part 1 5. Moreover, the part 1 5 defines an annular skirt portion 1 7 which extends within the part 1 6 for engagement with a flange 1 8 of a valve assembly generally indicated in
Figure 3 at 1 9, the other side of the flange being urged when the parts 1 5 and 1 6 are tightened, into sealing engagement with an inwardly directed end portion 20 of the part 16.
In addition, the part 1 5 is provided with a longitudinal passage 21 which is shaped at its outer end, to receive the shaped end of the fuel line 13. The threads at this end of the part 1 5 of the body are provided for engagement by a retaining nut which acts to retain the fuel line relative to the part 1 5.
It will be noted that the skirt portion 1 7 defines an outer annular space with the internal wall of the part 16 of the body part and conveniently this space in use, communicated with the atmosphere by way
of a passage (not shown). The skirt portion 1 7 is of
thin section for a purpose to be described but it
does act as part of the wall of a chamber to which fuel under pressure is supplied by the injection
pump.
In the arrangement shown in Figures 4 and 5 the body part is is of one piece construction and the valve assembly 1 9 is held in position within the body part by rolling over the end portion of the body part into contact with the flange 18 after the valve assembly has been located in the body part.
It should be noted however, that in the arrangements shown .in Figures 4 and 5 a separate annular member 22 is provided which corresponds to the skirt portion 1 7 of the example shown in Figure 3. As before, there is defined between the annular member 22 and the wall of the body part, an annular space which communicates with the atmosphere.
The nozzle shown in Figure 4 has a screw
thread whereby it can be secured within the bore
and it is also provided with a screw thread for
engagement by a nut for retaining the fuel line. In
the arrangement shown in Figure 5 the nozzle is
devoid of screw threads and it is held within the
bore by a nut which also serves to retain the shaped end of the fuel line in contact with the
body.
The valve assembly 1 9 will now be described
with reference to Figure 2. The flange 1 8 is formed on the periphery of a tubular member 23
having an internal bore 24 which at its lower end
is shaped to define a seating 25. Slidable within the bore is a valve member 26 having at its end
adjacent the seating a head 27 for co-operation with the seating. Also provided on the valve
member is a helically fluted portion 28 which cooperates with the wall of the bore to guide the movement of the valve member. Intermediate the portion 28 and the head 27 the valve member is provided with a recess portion 29.Moreover, the tubular member is provided with a pair of ports 30 adjacent its opposite end and these communicate with the interior of the aforesaid chamber to permit fuel flow along an annular clearance 31 defined between the wall of the bore 24 and a length of the valve member which is of reduced section.
The valve member is biased to the closed position i.e. the position shown in the drawings in which the head 27 is in contact with the seating 25, by means of a coiled compression spring 32 disposed between the flange 1 8 and an abutment 33. The abutment 33 is engaged about a portion of the valve member which extends from the bore 24 and conveniently this is of two part construction to facilitate the assembly thereof.
In use, fuel supplied through the passage 21 acts upon the valve member to urge the valve member downwardly as shown in the drawings thereby lifting the head 27 from the seating 25.
Such movement is of course against the action of the spring 32. When this movement occurs fuel from the chamber flows through the ports 30, along the clearance 31 through the channels defined by the fluted portion 28, through the clearance 29 and between the valve head and the seating. The fuel emerges from the nozzle as a finely divided spray which is directed into the combustion chamber of the engine.
As explained earlier in the specification it is desirable that the initial rate of flow of fuel to the combustion chamber should increase slowly. This is obtained by allowing the skirt portion 1 7 or the annular member 22, to flex outwardly under the action of the pressure of fuel supplied through the passage 21. The wall thickness therefore of the skirt portion 1 7 or the annular member 22 must be so chosen that the desired amount of flexure is obtained for the particular application. Towards the end of the period of delivery of fuel by the pump the pressure reduces. During this period the wall of the skirt portion 1 7 in the annular member 22 regains its original dimension and in so doing the volume of the chamber reduces thereby expelling fuel from the chamber. The pump will incorporate a delivery valve or a plurality of delivery valves depending
upon the type of pump, which act when the delivery of fuel ceases, to unload the fuel line
thereby allowing rapid closure of the valve
member 27 onto the seating 25.
Claims (9)
1. A fuel injection nozzle for supplying fuel to a
compression ignition engine comprising a hollow
body part, a valve assembly including a resiliently
loaded valve member and a seating, the valve
assembly being located within the body part with
a valve head forming part of the assembly being
exposed at or beyond one end of the body part,
and a fuel inlet communicating with the interior
of the body part, the arrangement being such that
in use, when fuel under pressure is supplied to the
inlet, the fuel pressure within the body part acting
upon the components of the valve assembly will
effect movement of the valve head away from the
body and the seating to permit fuel to flow past
the valve head and seating into in use, the
respective combustion chamber of the associated
engine, the nozzle being characterized by an annular
elongated part located within the body part, said
elongated part surrounding the portion of the
valve assembly lying within the body part, said
elongated part acting to define part of the wall of a
chamber to which fuel under pressure is supplied
from the inlet and from which fuel flows when the
head is moved out of contact with the seating, the
wall thickness of said elongated part being such
that the wall deflects during the initial delivery of
fuel to the nozzle thereby to store part of the initial
flow of fuel whereby the initial rate of flow of fuel
past the valve head and seating will be at a
reduced rate.
2. A nozzle according to claim 1 in which said
annular part defines an annular space with the
surrounding body part, said annular space in use
being substantially at atmospheric pressure.
3. A nozzle according to claim 1 in which said
hollow body part is formed in two parts one of said
parts being of hollow form having an inwardly
directed end portion for engagement by a flange
on the valve assembly, the other of said parts
being engageable within said one part and having
an integral skirt portion for engagement with said flange to retain the valve assembly within the body, said skirt portion constituting said annular elongated part, said fuel inlet being formed in said other part.
4. A nozzle according to claim 3 including complementary screw threads on said parts of the body said threads acting to retain said parts of the body part relative to each other.
5. A nozzle according-to claim 1 in which said annular elongated part comprises an annular member which is located within said body part.
6. A nozzle according to claim 5 including a flange on the valve assembly said flange being retained between said annular member and a portion of said body part.
7. A fuel injection nozzle unit for supplying fuel to a compression ignition internal combustion engine comprising the combination and arrangement of parts substantially as hereinbefore described with reference to Figure 3 of the accompanying drawings.
8. A fuel injection nozzle unit for supplying fuel to a compression ignition internal combustion engine comprising the combination and arrangement of parts substantially as hereinbefore described with reference to Figure 4 of the accompanying drawings.
9. A fuel injection nozzle unit for supplying fuel to a compression ignition internal combustion engine comprising the combination and arrangement of parts substantially as hereinbefore described with reference to Figure 5 of the accompanying drawings.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB7932882A GB2034812B (en) | 1978-11-17 | 1979-09-21 | Fuel injection nuozzles |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB7845088 | 1978-11-17 | ||
GB7932882A GB2034812B (en) | 1978-11-17 | 1979-09-21 | Fuel injection nuozzles |
Publications (2)
Publication Number | Publication Date |
---|---|
GB2034812A true GB2034812A (en) | 1980-06-11 |
GB2034812B GB2034812B (en) | 1983-01-19 |
Family
ID=26269640
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB7932882A Expired GB2034812B (en) | 1978-11-17 | 1979-09-21 | Fuel injection nuozzles |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB2034812B (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
USD762925S1 (en) | 2015-02-04 | 2016-08-02 | 3M Innovative Properties Company | Helmet rib |
-
1979
- 1979-09-21 GB GB7932882A patent/GB2034812B/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
GB2034812B (en) | 1983-01-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US5890660A (en) | Fuel injection nozzle | |
US5538187A (en) | Fuel injection device for internal combustion engines | |
US4394972A (en) | Fuel injection nozzles | |
KR890000775A (en) | Fuel injection pump | |
GB2023727A (en) | Fuel injector nozzle | |
US4513719A (en) | Fuel injector | |
US4537359A (en) | Fuel injection nozzles | |
US4274596A (en) | Fuel injection nozzles | |
GB2034812A (en) | Fuel injection nozzles | |
US4186884A (en) | Liquid fuel injection nozzles | |
US4153200A (en) | Fuel injection nozzles | |
US3628736A (en) | Liquid supply nozzles | |
US4887944A (en) | Fuel injection pump including plunger setting device | |
DE19752496A1 (en) | Fuel injection valve for internal combustion engines | |
US4549696A (en) | Fuel injection nozzles | |
US4065058A (en) | Fuel injection nozzle with compressible valve | |
US4513916A (en) | Fuel injection nozzle | |
EP0672826B1 (en) | Fuel injection nozzle | |
US4389018A (en) | Fuel injection nozzle for internal combustion engines | |
US4691864A (en) | Fuel injection nozzles | |
FR2561716A1 (en) | FUEL INJECTOR | |
GB2203795A (en) | I.C. engine fuel injection nozzle | |
JP3748116B2 (en) | Fuel injection device | |
JPH0158771U (en) | ||
GB2097058A (en) | Fuel injection nozzles |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PCNP | Patent ceased through non-payment of renewal fee |