Internal-combustion engines – Charge forming device – Fuel injection system
Reexamination Certificate
2003-06-13
2004-05-25
Mohanty, Bibhu (Department: 3747)
Internal-combustion engines
Charge forming device
Fuel injection system
C123S516000, C123S458000
Reexamination Certificate
active
06739318
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a fuel injection apparatus used in a marine engine such as an outboard motor for sailing on the sea.
2. Description of Conventional Art
A description will be given of a first example of a conventional fuel injection apparatus for the marine engine with reference to FIG.
4
.
Reference symbol T denotes a fuel tank in which fuel is stored, reference symbol V denotes a vapor separator within which a fixed fuel liquid surface X—X is formed, and reference symbol D denotes a fuel distribution pipe provided with fuel injection valves J injecting and supplying the fuel into an intake pipe of the engine.
Further, the vapor separator V is structured as follows.
Reference numeral
20
denotes a casing formed by a chamber
21
and a cover
22
. The chamber
21
is formed in a cup shape with a upper mounting collar portion
21
A and a lower closed end, the cover
22
is formed in a cup shape from a lower mounting collar portion
22
A and an upper closed end, and a fuel storage space is formed by bringing the respective mounting collar portions
21
A and
22
A of the chambers
21
and the cover
22
into contact with each other.
Reference symbol F denotes a fixed liquid surface control mechanism which forms and keeps the fixed fuel liquid surface X—X within the vapor separator V. The fixed liquid surface control mechanism F is constituted by a valve seat
24
which is connected to an inflow passage
23
formed in the cover
22
and is open to the inside of the vapor separator V, a float valve
25
which opens and closes the valve seat
24
, and a float
27
which is rotatably supported to an axis
26
, swings in correspondence to a liquid surface height formed within the vapor separator V, and controls so as to open and close the valve seat
24
via the float valve
25
.
Further, a high pressure fuel pump HP is arranged within the vapor separator V, and this fuel pump HP is constituted by a motor portion and a pump portion.
The fuel pump HP is provided with a fuel discharge hole
28
and a fuel suction hole
29
, the fuel suction hole
29
is arranged so as to be below the fuel liquid surface X—X within the vapor separator V, and the fuel discharge hole
28
is arranged so as to be connected to a fuel discharge passage
30
provided in the cover
22
.
Reference symbol R denotes a pressure regulator which regulates a fuel pressure to a predetermined pressure. The pressure regulator R is structured as follows. A diaphragm
33
is clamped between a lower housing
31
and an upper housing
32
, a fuel chamber
34
is formed by the diaphragm
33
and the lower housing
31
, and a spring chamber
35
is formed by the diaphragm
33
and the upper housing
32
.
Further, a fuel inflow hole
36
and a return fuel hole
37
are open to the fuel chamber
34
, and a return valve seat
38
is provided in an open end of the return fuel hole
37
to the fuel chamber
34
.
An opening of the return valve seat
38
to the fuel chamber
34
is controlled by a valve body
39
which is synchronously moved together with the diaphragm
33
.
Further, a spring
40
pressing the diaphragm
33
toward the fuel chamber
34
is provided compressedly within the spring chamber
35
, and a vent hole
41
is open to the spring chamber
35
. Further, the pressure regulator R is arranged on a top surface of the cover
22
, and at this time, the fuel in flow hole
36
is arranged so as to be connected to a pressure fuel inflow passage
42
formed in the cover
22
, and the return fuel hole
37
is arranged so as to be open to an inside of the vapor separator V.
The vapor separator V provided with the pressure regulator R mentioned above is connected to the other structures by passages in accordance with the following manner.
The fuel tank T and the inflow passage
23
of the vapor separator V are connected by a fuel inflow pipe
43
, and a low pressure fuel pump LP is arranged in the fuel inflow pipe
43
.
The fuel discharge passage
30
formed in the vapor separator V and connected to the fuel discharge hole
28
of the high pressure fuel pump HP is connected to the fuel distribution pipe D by a fuel discharge pipe
44
.
The pressure fuel inflow passage
42
formed in the cover
22
and connected to the fuel inflow hole
36
of the pressure regulator R is connected to the fuel discharge pipe
44
by a regulator fuel pipe
45
.
In accordance with the structure mentioned above, pressure of the fuel within the fuel tank T is increased by the low pressure fuel pump LP, and the fuel having the increased pressure is supplied into the casing
20
of the vapor separator V via the fuel inflow pipe
43
, the inflow passage
23
and the valve seat
24
, and forms and keeps the fixed fuel liquid surface X—X within the casing
20
by the fixed liquid surface control mechanism F constituted by the valve seat
24
, the float valve
25
and the float
27
.
On the other hand, pressure of the fuel stored within the vapor separator V is increased in pressure by the high pressure fuel pump HP, and is supplied into the fuel distribution pipe D via the fuel discharge hole
28
, the fuel discharge passage
30
and the fuel discharge pipe
44
, and at this time, the pressure of the fuel moving toward the fuel distribution pipe D is regulated to a predetermined pressure by the pressure regulator R.
That is, a part of the fuel flowing within the fuel discharge pipe
44
flows into the fuel chamber
34
of the pressure regulator R via the regulator fuel pipe
45
, the pressure fuel inflow pipe
42
and the fuel inflow hole
36
, is filled in the fuel chamber
34
so as to press up the valve body
39
via the diaphragm
33
, and balances with a spring force of the spring
40
at set pressure (predetermined pressure), whereby it is possible to regulate the pressure of the fuel flowing within the fuel discharge pipe
44
to predetermined pressure.
On the other hand, the valve body
39
is moved upward, whereby the return valve seat
30
is released. Accordingly, the fuel within the fuel chamber
34
is discharged into the casing
20
of the vapor separator V via the return fuel hole
37
.
A second example of the conventional fuel injection apparatus for the marine engine is shown in FIG.
5
.
In this case, the same reference symbols are attached to the same structure parts as those in
FIG. 4
, and a description thereof will be omitted.
The second example is different from the first example in view of an arrangement of the pressure regulator R.
That is, the pressure regulator R is arranged within the casing
20
of the vapor separator V and at a position below the fixed fuel liquid surface X—X, and the lower housing
31
is arranged in a bottom portion
21
B of the chamber
21
.
Further, the pressure fuel inflow passage
42
provided in the chamber
21
connected to the fuel inflow hole
36
of the pressure regulator R is connected to the fuel distribution pipe D by the regulator fuel pipe
45
.
Accordingly, the pressure of fuel flowing within the fuel distribution pipe D is controlled to predetermined fuel pressure by a pressure regulating operation of the pressure regulator R.
In accordance with the first example of the conventional fuel injection apparatus, the pressure regulator R is arranged on the cover
22
of the vapor separator V, whereby the following problems are generated.
That is, since at least upper housing
32
of the pressure regulator R protrudes from the cover
22
and is arranged so as to be directly exposed to the ambient air, it is necessary to apply a corrosion resisting or rust proofing treatment to the upper housing
32
or use a corrosion resisting material for the upper housing
32
, whereby it is impossible to effectively reduce a manufacturing cost for the upper housing
32
.
Further, since the vent hole
41
is pierced so as to be open to the upper housing
32
, there is a risk that sea water enters into the spring chamber
35
of the pressure regulator R from the vent hole
41
, whereby there is generated a problem that parts such as the
Coleman Henry
Keihin Corporation
Mohanty Bibhu
Sapone William
Sudol R. Neil
LandOfFree
Fuel injection apparatus for marine engine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Fuel injection apparatus for marine engine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Fuel injection apparatus for marine engine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3263951