Information
-
Patent Grant
-
6659089
-
Patent Number
6,659,089
-
Date Filed
Wednesday, June 19, 200222 years ago
-
Date Issued
Tuesday, December 9, 200320 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Birch, Stewart, Kolasch & Birch, LLP
-
CPC
-
US Classifications
Field of Search
-
International Classifications
-
Abstract
To augment the durability of a turbocharger. A hull and a deck of a personal watercraft are formed watertight and an opening of the deck is closed with a seat to form a body internal space. An intake duct for introducing atmospheric air from outside the body is provided in the space. An engine and a turbocharger connected to an exhaust manifold of the engine are provided in the space and the turbocharger is disposed higher than a body internal opening of the intake duct. A water jacket is formed in a casing of a turbine portion of the turbocharger and an oil jacket is formed in a bearing casing of the turbocharger, and cooling water is supplied to the water jacket and cooling oil is supplied to the oil jacket. The cooling water to the water jacket is supplied by a different turbocharger cooling water passage independent of any other cooling water passage.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application claims priority under 35 USC 119 to Japanese Patent Application No. 2001-219321 filed on Jul. 19, 2001 the entire contents thereof is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a turbocharger arrangement structure for a personal watercraft.
2. Description of Background Art
While the power source in widespread personal watercrafts conventionally is a 2-cycle engine, it has been considered to use a 4-cycle engine for the power source in order to cope with a reduction in pollution in recent years.
However, since the output power of the 4-cycle engine is lower than that of the 2-cycle engine of the same total stroke volume, it is examined to incorporate an engine with a turbocharger in order to make up the power. The assignee of the present invention has proposed a personal watercraft in which an engine with a turbocharger is incorporated as disclosed in Japanese Patent Laid-Open No. 2001-140641.
In this personal watercraft, a 4-cycle engine
2
with a turbocharger
3
is incorporated inside of a body
1
as shown in
FIGS. 11 and 12
.
As shown also in
FIGS. 13 and 14
, an exhaust manifold
4
is provided on the left side of the 4-cycle engine
2
in an advancing direction F of the body
1
. An intake chamber
5
is provided on the right side of the 4-cycle engine
2
.
Exhaust gas from an exhaust gas exit
4
a
of the exhaust manifold
4
is introduced into a turbine portion
3
T of the turbocharger
3
, and compressed air from a compressor portion
3
C of the turbocharger
3
is supplied into the intake chamber
5
described above through an intercooler
6
.
In such a personal watercraft as described above, in order to make it difficult for water to enter a body
1
, it is necessary to form a hull
1
a
(refer to
FIG. 11
) and a deck
1
b
to be watertight and to close an opening in the deck with a lid member (for example, a seat
7
) to form an internal body space
1
c.
Meanwhile, in order to ensure intake of air into an engine
2
, it is necessary to introduce atmospheric air from outside the body into the body internal space
1
c
. In a personal watercraft wherein a turbocharger is provided for an engine, when the atmospheric air outside the body is introduced into the body internal space
1
c
during operation of the personal watercraft, air is sometimes introduced together with water (for example, in the form of droplets) into the body. If the turbocharger is exposed to the water, then a casing and so forth of the turbocharger whose temperature is high is cooled suddenly and partially, which gives rise to disadvantages such as thermal fatigue that is liable to occur with the turbocharger.
SUMMARY AND OBJECTS OF THE INVENTION
The object of the present invention resides in a solution of such a problem as described above to provide a turbocharger arrangement structure for a personal watercraft which makes the turbocharger less liable to be exposed to water.
In order to attain the object described above, according to the present invention, a turbocharger arrangement structure for a personal watercraft includes a hull and a deck of the personal watercraft that are formed to be watertight and an opening of the deck that is closed up with a lid member to form a body internal space. An intake duct for introducing the atmospheric air outside the body is provided in the space while an engine and a turbocharger connected to an exhaust manifold of the engine are provided in the space and the turbocharger is disposed to be higher than a body internal opening of the intake duct.
According to the present invention, the turbocharger arrangement structure for a personal watercraft according to the present invention provides a water jacket that is formed in a casing of a turbine portion of the turbocharger and an oil jacket that is formed in a bearing casing of the turbocharger, and cooling water is supplied to the water jacket and cooling oil is supplied to the oil jacket.
According to the present invention, the turbocharger arrangement structure for a personal watercraft according to the present invention provides the cooling water to the water jacket that is supplied by a different turbocharger cooling water passage independent of any other cooling water passage.
With the turbocharger arrangement structure for a personal watercraft according to the present invention, the hull and the deck of the personal watercraft are formed to be watertight and the opening of the deck is closed up with the lid member to form the body internal space. The intake ducts for introducing the atmospheric air outside the body are provided in the space and the engine and the turbocharger are connected to the exhaust manifold of the engine and are provided in the space. The turbocharger is disposed to be higher than the body internal openings of the intake ducts. Therefore, when the atmospheric air outside the body is introduced into the body internal space through the intake ducts during operation of the personal watercraft, even if air is introduced together with water (for example, in the form of droplets), such a situation wherein the turbocharger becomes wet directly with the water becomes less likely to occur.
Accordingly, a situation wherein the casing and so forth of the turbocharger, whose temperature is high, are cooled suddenly and partially becomes less likely to occur. Thus thermal fatigue becomes less likely to occur with the turbocharger. As a result, the durability of the turbocharger is augmented.
The turbocharger arrangement structure for a personal watercraft according to the present invention provides a water jacket that is formed in the casing of the turbine portion of the turbocharge and the oil jacket is formed in the bearing casing for the turbocharger. Cooling water is supplied to the water jacket and cooling oil is supplied to the oil jacket. Consequently, such a situation wherein the temperature of the turbocharger becomes excessively high is eliminated.
Accordingly, when the atmospheric air outside the body is introduced into the body internal space through the intake ducts during operation of the personal watercraft, even if air is introduced together with water (for example, in the form of droplets) and the turbocharger becomes exposed to the water, the temperature variation of the casing of the turbocharger by the water is suppressed to be small.
As a result, thermal fatigue becomes less likely to occur with the turbocharger, and the durability of the turbocharger is augmented with certainty.
With the turbocharger arrangement structure for a personal watercraft according to the present invention, cooling water for the water jacket is supplied through the different turbocharger cooling water passages independent of the other cooling water passages. Thus, the turbocharger is cooled efficiently.
Accordingly, when the atmospheric air outside the body is introduced into the body internal space through the intake ducts during operation of the personal watercraft, even if air is introduced together with water (for example, in the form of droplets) and the turbocharger is exposed to the water, the temperature variation of the casing of the turbocharger by the water is suppressed smaller.
As a result, thermal fatigue becomes further less likely to occur with the turbocharger, and the durability of the turbocharger is augmented with a higher degree of certainty.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by illustration only, and thus are not limitative of the present invention, and wherein:
FIG. 1
is a schematic side elevational view showing an example of a watercraft which uses an embodiment of the turbocharger arrangement for a personal watercraft according to the present invention;
FIG. 2
is a plan view of the personal watercraft in
FIG. 1
;
FIG. 3
is a partial enlarged sectional view (partly omitted sectional view) taken along line III—III of
FIG. 1
;
FIG. 4
is a view principally showing an engine
20
and is a partial enlarged sectional view (partly omitted sectional view) taken along line IV—IV of
FIG. 1
;
FIG. 5
is a right side elevational view of the engine
20
;
FIG. 6
is a left side elevational view of the engine
20
;
FIG. 7
is a schematic perspective view of the engine
20
as viewed from obliquely rearwardly;
FIG. 8
is a partial enlarged view of
FIG. 5
;
FIG. 9
is a view of a circulation route of oil;
FIG. 10
is a sectional view of a turbocharger
140
;
FIG. 11
is an explanatory view of the prior art;
FIG. 12
is an explanatory view of the prior art;
FIG. 13
is an explanatory view of the prior art; and
FIG. 14
is an explanatory view of the prior art.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the following, an embodiment of the present invention is described with reference to the drawings.
As shown in
FIG. 1
, a personal watercraft
10
is a personal watercraft of the type, wherein a driver can sit on a seat
12
on a body
11
and grip a steering
13
with a throttle lever to steer the personal watercraft
10
.
The body
11
has a floating body structure wherein a hull
14
and a deck
15
are joined together such that a space
16
is formed inside thereof. An opening
15
a
(refer to
FIG. 4
) of the deck
15
is closed up with the seat
12
serving as a lid member removably mounted on the deck
15
. In the space
16
, an engine
20
is mounted on the hull
14
, and a jet pump (jet propulsion pump)
30
as propulsion means which is driven by the engine
20
is provided at a rear portion of the hull
14
.
The jet pump
30
has a passage
33
extending from an intake
17
open to the bottom to a jet outlet
31
and a nozzle
32
open to the rear end of the body and an impeller
34
disposed in the passage
33
. A shaft
35
of the impeller
34
is connected to an output power shaft
21
a
of the engine
20
. Accordingly, if the impeller
34
is driven to rotate by the engine
20
, then water taken in from the intake
17
is jetted from the nozzle
32
through the jet outlet
31
so that the body
11
is propelled. The driving speed of the engine
20
, that is, the propelling force by the jet pump
30
, is operated by a pivoting operation of a throttle lever
13
a
(refer to
FIG. 2
) of the steering handle
13
described above. The nozzle
32
is operatively associated with the steering handle
13
by an operation wire not shown such that it is pivoted by an operation of the steering handle
13
, and the advancing direction can be changed thereby.
A fuel tank
40
and an accommodation chamber
41
are operatively connected to the body
11
.
As illustrated in
FIG. 4
, the engine
20
is a DOHC in-line four-cylinder dry sump type 4-cycle engine and is disposed such that the crankshaft
21
a
thereof extends in the forward and backward direction of the body
11
as shown in FIG.
1
.
As shown in
FIGS. 4 and 7
, a surge tank (intake chamber)
22
and an intercooler
23
communicated with an intake port are connected and disposed on the left side of the engine
20
with respect to the advancing direction of the body
11
, and an exhaust manifold
24
is in communication with an exhaust port
200
and is connected and disposed on the right side of the engine
20
.
As shown in
FIGS. 6 and 7
, a turbocharger (turbocharger)
140
is disposed rearwardly of the engine
20
, and an exhaust gas exit
24
o
of the exhaust manifold
24
is connected to a turbine portion
140
T of the turbocharger
140
while the intercooler
23
is connected to a compressor portion
140
C of the turbocharger
140
by a pipe
26
(refer to FIG.
7
). In
FIG. 7
, a cooling water hoses
23
a
,
23
b
are connected to the intercooler
23
.
It is to be noted that exhaust gas which has rotated a turbine in the turbine portion
140
T of the turbocharger
140
passes, as shown in
FIGS. 1 and 2
, through an exhaust pipe
27
a
, a backflow preventing chamber
27
b
for preventing a backflow of water (admission of water into the turbocharger
140
and so forth). Upon capsize, a water muffler
27
c
and an drain pipe
27
d
and is exhausted into a water stream produced by the jet pump
30
.
Referring to
FIG. 1
, intake ducts
18
,
19
are provided for introducing the atmospheric air outside the body
11
into the space
16
in the body
11
. Lower ends
18
a
,
19
a
of the intake ducts
18
,
19
are provided to be lower than the turbocharger
140
described above in the body
11
. In other words, the turbocharger
140
is provided to be higher than the openings
18
a
,
19
a
of the intake ducts
18
,
19
in the body. The turbocharger
140
is provided substantially in the center in the vertical direction in the space
16
of the body.
As shown in
FIGS. 4
to
7
, an oil tank
50
and an oil pump
80
are provided integrally on an extension line of a crankshaft
21
at a front portion of the engine
20
(in the advancing direction of the body
11
, and at a left portion in FIGS.
1
and
5
). The oil pump
80
is provided in the oil tank
50
.
The oil tank
50
is formed from a tank body (one divided case)
60
joined to a front face of the engine
20
and a cover (the other divided case)
70
joined to a front face of the tank body
60
.
As shown in
FIGS. 4 and 6
, a water cooling type oil cooler
90
is provided on the front face of the tank body
60
in the oil tank
50
, and an oil filter
100
is provided at an upper portion of the oil tank
50
.
As shown in
FIGS. 4
,
5
and
8
, the tank body
60
has a joining face
61
to the front face of the engine
20
, a joining face
62
to the cover
70
, a mounting portion
63
for the oil pump
80
, a mounting portion
64
for the water cooling type oil cooler
90
, a generally vertically elongated oil accommodation portion
65
defined by partition walls and outer walls which form the mounting surfaces of them, an ACG
110
, balancer shafts
114
L,
114
R, and a cover portion
66
for a drive chamber of a starter motor
120
. Further, as shown in
FIG. 6
, the tank body
60
has a mounting portion
68
for the oil filter
100
.
The tank body
60
is joined at the joining face
61
thereof described above to the front face of the engine
20
and integrally secured to the front face of the engine
20
by bolts not shown in such a manner that it covers the elements described above. It is to be noted that the tank body
60
is attached to the front face of the engine
20
after the oil pump
80
and the type oil cooler
90
are attached thereto.
The cover
70
has a joining face
71
to the tank body
60
, a refilling opening
72
for oil, a holding portion
73
for a relief valve
130
, an accommodation portion
74
(refer to
FIG. 6
) for the oil cooler
90
, and an oil accommodation portion
75
defined by outer walls and a partition wall.
The oil pump
80
includes a first case
81
joined to the tank body
60
described above, a second case
82
joined to the first case
81
, a pump shaft
83
provided such that it extends through the first and second cases, inner and outer rotors
84
coupled to the pump shaft
83
in the first case
81
described above for recovering oil, and inner and outer rotors
85
coupled to the pump shaft
83
in the second case
82
described above for supplying oil.
The inner and outer rotors
84
for recovering oil cooperates with the first case
81
to form an oil recovery pump, and the inner and outer rotors
85
for supplying oil cooperates with the first and second cases
81
,
82
to form an oil supply pump.
The oil pump
80
is attached to the front face of the tank body
60
by means of bolts
88
after the joining face of the first case
81
to the tank body
60
is jointed to the mounting portion
63
on the front face of the tank body
60
formed in the same shape as that of the joining face.
After the oil pump
80
is attached to the tank body
60
in this manner, a coupling
89
is secured to the rear end of the pump shaft
83
from the rear face side of the tank body
60
by means of bolts.
Accordingly, the tank body
60
is attached to the front face of the engine
20
such that the coupling
89
is coupled to a coupling
111
provided at an end of an ACG shaft after the oil pump
80
and the coupling
89
are attached and further the oil cooler
90
is attached.
The water cooling type oil cooler
90
is attached to the front face side of the mounting portion
64
of the tank body
60
for the oil cooler
90
.
As shown in
FIGS. 4 and 6
, an upper hole
64
a
and a lower hole
64
b
which are in communication with an oil passage which is hereinafter described are formed in the mounting portion
64
of the tank body
60
.
The oil cooler
90
has a plurality of heat exchanging plates
91
through the inside of which oil passes, an entrance pipe
92
for oil in communication with an upper portion thereof with the inside of the plates
91
. An exit pipe
93
is provided for oil in communication with a lower portion thereof with the inside of the plates
91
.
Accordingly, the oil cooler
90
is attached to the mounting portion
64
of the tank body
60
such that the entrance pipe
92
thereof is connected to the upper hole
64
a
of the tank body
60
and the exit pipe
93
thereof is connected to the lower hole
64
b
of the tank body
60
.
As shown in
FIGS. 4 and 6
, a cooling water introduction pipe
97
is in communication with a hole
64
c
open to the mounting portion
64
and introduces cooling water into the accommodation portion
74
of the oil cooler in the mounting portion
64
and the cover
70
is provided on the tank body
60
. A discharge pipe
78
is provided for water in the cover
70
. A cooling water hole
97
a
from a cooling water output port
30
a
(refer to
FIG. 7
) of the jet pump
30
is connected directly to the introduction pipe
97
without intervention of any other cooling device. An drain pipe
23
c
is connected to the discharge pipe
78
as shown in FIG.
6
. Water from the discharge pipe
78
is supplied into the water jacket of the exhaust manifold
24
through the drain pipe
23
c.
The cover
70
is joined to the front face of the tank body
60
and secured by means of bolts not shown such that a front end
132
of the relief valve
130
is held down by the holding portion
73
described hereinabove after the tank body
60
, oil pump
80
and oil cooler
90
are attached to the front face of the engine
20
in such a manner as described above. Thereafter, a rear end
131
of the relief valve
130
is fitted into a hole
82
a
formed in the front face of the second case
82
of the oil pump
80
as shown in
FIGS. 5 and 8
. The relief valve
130
is disposed horizontally in this manner.
In the state wherein the tank body
60
and the cover
70
are joined together, a single oil accommodation section is formed from the oil accommodation portions
65
,
75
.
Further, the oil filter
100
is attached to the mounting portion
68
of the tank body
60
for the oil filter
100
.
It is to be noted that, in a state wherein the engine
20
is incorporated in the body
11
, the engine
20
and the oil filter
100
are opposed to the opening
15
a
of the deck
15
as shown in
FIGS. 2 and 4
. The opening
15
a
of the deck
15
is opened by removing the seat
12
, which is removably mounted on the body
11
.
Such oil passages as described below are formed in a state wherein the oil tank
50
(that is, the tank body
60
, the cover
70
, and the oil pump
80
, oil cooler
90
, and relief valve
130
built in them) is mounted on the front face of the engine
20
and the oil filter
100
is mounted therein.
As shown in
FIGS. 5 and 8
, an oil recovery passage
51
is formed by the front face of the tank body
60
and the rear face of the first case
81
of the oil pump
80
. The recovery passage
51
is formed from an oil passage
51
a
formed on the tank body
60
side and an oil passage
51
b
formed on the first case
81
side of the oil pump
80
in an opposing relationship to the oil passage
51
a.
A lower end
51
c
of the oil recovery passage
51
is in communication with an oil pan
28
of the engine
20
through a pipe
52
. An upper end
51
d
of the oil recovery passage
51
is in communication with a recovered oil inlet port
81
i
formed in the first case
81
of the oil pump
80
.
Similarly, a discharge passage
53
for recovered oil is formed by the front face of the tank body
60
and the rear face of the first case
81
of the oil pump
80
. The discharge passage
53
is formed from an oil passage
53
a
formed on the tank body
60
side and a recovered oil discharge port
81
o
formed on the first case
81
side of the oil pump
80
in an opposing relationship to the oil passage
53
a.
An upper end
53
b
of the discharge path
53
is open to the inside of the oil tank
50
(that is, to the inside of the oil accommodation section).
Meanwhile, an intake passage
54
and a discharge passage
55
for supply oil are formed by the front face of the first case
81
and the rear face of the second case
82
of the oil pump
80
.
A lower end
54
a
of the intake passage
54
is open to the inside of the oil tank
50
(that is, to the inside of the oil accommodation section), and an upper end
54
b
of the intake passage
54
is in communication with a supply oil inlet port
82
i
of the oil supply pump. A screen oil filter
54
c
is provided in the intake passage
54
.
A lower end
55
a
of the discharge passage
55
is in communication with a supply oil discharge port
82
o
of the oil supply pump, and an upper end
55
b
of the discharge passage
55
extends horizontally through an upper portion of the first case
81
and is in communication with a horizontal hole
60
a
formed in the tank body
60
. The horizontal hole
60
a
is communicated with a vertical hole
60
b
similarly formed in the tank body
60
. An upper end
60
c
of the vertical hole
60
b
is open in the form of a ring as viewed in plan to the mounting portion
68
of the oil filter
100
. An oil inlet passage
101
of the oil filter
100
is in communication with the opening
60
c.
The mounting hole
82
a
for the relief valve
130
described hereinabove is open to the discharge passage
55
, and the relief valve
130
is attached in such a manner as described above to the mounting hole
82
a.
A male thread is provided on an oil exit pipe
102
in the oil filter
100
. The oil filter
100
is attached to the mounting portion
68
of the tank body
60
by screwing the oil exit pipe
102
into a female threaded hole
60
d
formed in the mounting portion
68
of the tank body
60
.
As shown in
FIG. 6
, a vertical hole
60
e
and a horizontal hole
60
f
are in communication with a lower end of the vertical hole
60
e
and are formed at a lower portion of the female threaded hole
60
d
in the tank body
60
. The horizontal hole
60
f
is in communication with the entrance pipe
92
of the oil cooler
90
through the upper hole
64
a
of the mounting portion
64
of the oil cooler
90
described hereinabove.
Meanwhile, an oil passage
60
g
communicating with the lower hole
64
b
and an oil distributing passage
60
h
communicating with the passage
60
g
are formed in the lower hole
64
b
of the tank body
60
described hereinabove to which the exit pipe
93
of the oil cooler
90
is connected. Further, a main gallery supply passage
60
i
for supplying oil to a main gallery
20
a
(refer to
FIG. 5
) of the engine
20
, a left balancer supply passage
60
j
for supplying oil to bearing portions of the left balancer
114
L described hereinabove and a right balancer supply passage
60
k
for supplying oil to bearing portions of the right balancer
114
R are in communication with the oil distributing passage
60
h.
It is to be noted that one end of the oil distributing passage
60
h
is closed up with a plug
60
n
(refer to FIG.
6
).
The route of oil supplied to the main gallery
20
a
of the engine
20
is such as shown in
FIG. 9
(oil circulation route diagram).
The route from the main gallery
20
a
is generally divided into two.
The first route is a route along which oil is supplied to bearing portions of the crankshaft
21
through a route
20
b
(refer to FIG.
5
), and the second route is a route along which oil is supplied from a rear end
20
a
1
of the main gallery
20
a
through a pipe
25
a
(refer to
FIG. 7
) to cool and lubricate turbine bearings of the turbocharger
140
. The oil which has cooled and lubricated the turbine bearings of the turbocharger
140
is recovered into the oil pan
28
through pipes
25
b
,
25
c
(refer to FIG.
6
).
The oil supplied to the bearing portions of the crankshaft
21
further lubricates cam journal
20
d
portions and lifter portions of a cylinder head through a route
20
c
and then returns to the oil pan
28
through a chain chamber
20
i.
Meanwhile, the oil supplied to the bearing portions of the crankshaft
21
is further supplied to the ACG, piston rear jet nozzles, connecting rod, cam chain and starter needle and is recovered into the oil pan
28
through respective recovery passages. In
FIG. 5
, a jet nozzle
20
e
is provided for jetting oil to the rear side of the piston to cool the piston. A passage
20
f
is provided to the connecting rod portion. A cam chain
20
g
is operatively connected to the engine. Further, a return passage
20
h
provides a returning passage for oil from an ACG chamber
110
c.
The oil in the ACG chamber returns to the oil pan
28
through a return passage
20
h
therefor, and the oil jetted to the rears of the pistons from jet nozzles
20
e
, the oil supplied to the connecting rod and the oil supplied to the starter needle return to the oil pan
28
individually through a crank chamber
20
j.
As is apparent from the foregoing description, a general flow of oil is described below with reference principally to FIG.
9
.
Oil flows from the oil tank
50
to the intake passage
54
to the screen oil filter
54
c
to the oil pump (supply pump)
80
to the discharge passage
55
(and relief valve
130
, horizontal hole
60
a
, vertical hole
60
b
, ring-form opening
60
c
) to the oil filter
100
to the vertical hole
60
e
, horizontal hole
60
f
to the oil cooler
90
to the oil passage
60
g
, oil distributing passage
60
h
to the main gallery supply passage
60
i
, left balancer supply passage
60
j
, right balancer supply passage
60
k
and to the main gallery
20
a
, left balancer
114
L, right balancer
114
R.
Relief oil RO from the relief valve
130
returns directly into the oil tank
50
.
Oil supplied to the left balancer
114
L, right balancer
114
R returns to the oil pan
28
through the crank chamber
20
j.
Meanwhile, oil supplied to the various portions described above from the main gallery
20
a
returns to the oil pan
28
in such a manner as described above.
Then, the oil returned to the oil pan
28
is recovered into the oil tank
50
through the pipe
52
, recovery passage
51
, oil pump
80
(recovery pump) and recovered oil discharge path
53
, and is circulated by the route described above from the intake passage
54
.
FIG. 10
is a sectional view of the turbocharger
140
.
As described above, the turbocharger
140
includes the turbine portion
140
T and the compressor portion
140
C. The turbocharger
140
further includes a bearing casing
141
which interconnects the turbine portion
140
T and the compressor portion
140
C.
A bearing portion (accommodation chamber for a bearing member)
142
is provided in the bearing casing
141
, and a turbine shaft
143
is supported for rotation by bearing members (ceramic ball bearings)
142
a
of the bearing portion
142
.
Turbine blades
143
T are secured to the turbine shaft
143
adjacent the turbine portion
140
T, and compressor blades
143
C are secured to the turbine shaft
143
adjacent the compressor portion
140
C.
Accordingly, within a process wherein exhaust gas from the exhaust manifold
24
described hereinabove is exhausted from an exhaust gas exit T
2
to the exhaust pipe
27
a
(refer to
FIGS. 1 and 2
) described hereinabove through an exhaust passage T
1
in the turbine portion
140
T, the turbine shaft
143
is driven to rotate, and the compressor blades
143
C are driven to rotate so that air from an intake air inlet port C
1
communicating with an intake box not shown is fed under pressure from the pipe
26
(refer to
FIG. 7
) to the intercooler
23
through an intake passage C
2
in the compressor portion
140
C.
An oil entrance
144
is provided at an upper portion of the bearing casing
141
. The oil entrance
144
is in communication with the rear end portion
20
a
1
of the main gallery
20
a
by the pipe
25
a
(refer to
FIG. 7
) described hereinabove which services as an oil supply passage. The pipe
25
a
is connected to the oil entrance
144
by an orifice bolt
145
.
An oil jacket
146
is formed inside of the bearing casing
141
, and the oil entrance
144
described above is in communication with the oil jacket
146
by an oil passage
144
a
. The bearing portion
142
is in communication with the oil entrance
144
by a thin oil passage
144
b.
Accordingly, oil entering from the oil entrance
144
is supplied from the oil passage
144
a
to the oil jacket
146
to cool the bearing casing
141
, bearing portion
142
, turbine shaft
143
and members around them, and is supplied from the oil passage
144
b
to the bearing portion
142
to lubricate the bearing portion
142
.
The oil of the oil jacket
146
is recovered into the oil pan
28
from oil exits
146
a
and
146
b
of the oil jacket
146
through the pipes
25
b
,
25
c
(refer to
FIG. 6
) described hereinabove. Meanwhile, the oil of the bearing portion
142
once enters the oil jacket
146
from an exit
142
b
of the bearing portion
142
and then is recovered into the oil pan
28
from the oil exits
146
a
and
146
b
of the oil jacket
146
described above through the pipes
25
b
,
25
c
(refer to
FIG. 6
) described hereinabove.
The pipe
25
b
is connected to the oil exit
146
a
, and the pipe
25
c
is connected to the oil exit
146
b.
The oil exits
146
a
,
146
b
are disposed higher than an oil surface O
1
(refer to
FIG. 6
) when the engine stops.
Further, a one-way valve
147
is interposed in each of the pipes
25
b
,
25
c
which serve as an oil returning path.
As shown in
FIG. 10
, a water jacket T
3
is formed in the casing of the turbine portion
140
T. An entrance T
4
for cooling water of the water jacket T
3
is connected to the cooling water output port
30
a
(refer to
FIG. 7
) of the jet pump
30
described hereinabove by a pipe
148
a
which forms a different turbocharger cooling water passage independent of the other cooling water passages. Further, an exit (not shown) of the water jacket T
3
for cooling water is connected to a water jacket of the exhaust pipe
27
a
(refer to
FIGS. 1
,
2
) by a pipe
148
b
shown in FIG.
7
.
Accordingly, cooling water from the jet pump
30
is supplied to the water jacket T
3
of the turbocharger
140
directly without intervention of any other cooling device and cools the turbocharger
140
. Whereafter, the water cools the exhaust pipe
27
a
. It is to be noted that the water having cooled the exhaust pipe
27
a
further flows into a water jacket of the backflow preventing chamber
27
b
to cool the backflow preventing chamber
27
b
and is then jetted into the water muffler
27
c
, whereafter it is discharged together with exhaust gas into water current produced by the jet pump
30
through the exhaust and drain pipe
27
d.
According to such a turbocharger arrangement structure for a personal watercraft as described above, the following operation and effects are obtained.
The hull
14
and the deck
15
of the personal watercraft are formed watertight and the opening
15
a
of the deck
15
is closed up with the lid member
12
to form the body internal space
16
. The intake ducts
18
,
19
for introducing the atmospheric air from outside the body are provided in the space
16
and the engine
20
and the turbocharger
140
are connected to the exhaust manifold
24
of the engine
20
and are provided in the space
16
. In addition, the turbocharger
140
is disposed higher than the body internal openings
18
a
,
19
a
of the intake ducts
18
,
19
. Therefore, when the atmospheric air outside the body is introduced into the body internal space
16
through the intake ducts
18
,
19
during operation of the personal watercraft, even if it is introduced together with water (for example, in the form of droplets), such a situation that the turbocharger
140
becomes wet directly with the water becomes less likely to occur.
Accordingly, such a situation wherein the casing and so forth of the turbocharger
140
whose temperature is high are cooled suddenly becomes partially less likely to occur. In addition, and thermal fatigue becomes less likely to occur with the turbocharger
140
. As a result, the durability of the turbocharger
140
is augmented.
The water jacket T
3
is formed in the casing of the turbine portion
140
T of the turbocharger
140
and the oil jacket
146
is formed in the bearing casing
141
for the turbocharger
140
. Cooling water is supplied to the water jacket T
3
and cooling oil is supplied to the oil jacket
146
. Consequently, such a situation wherein the temperature of the turbocharger
140
becomes excessively high is eliminated.
Accordingly, when the atmospheric air outside the body is introduced into the body internal space
16
through the intake ducts
18
,
19
during operation of the personal watercraft, even if the air is introduced together with water (for example, in the form of droplets) and the turbocharger
140
becomes exposed to the water, the temperature variation of the casing of the turbocharger
140
by the water is suppressed small.
As a result, thermal fatigue becomes less likely to occur with the turbocharger
140
, and the durability of the turbocharger
140
is augmented with certainty.
Since cooling water for the water jacket T
3
is supplied through the different turbocharger cooling water passage
148
a
independent of the other cooling water passages, the turbocharger
140
is cooled efficiently.
Accordingly, when the atmospheric air outside the body is introduced into the body internal space
16
through the intake ducts
18
,
19
during operation of the personal watercraft, even if it is introduced together with water (for example, in the form of droplets) and the turbocharger
140
becomes exposed to the water, the temperature variation of the casing of the turbocharger
140
by the water is suppressed smaller.
As a result, thermal fatigue becomes further less likely to occur with the turbocharger
140
, and the durability of the turbocharger
140
is augmented with a higher degree of certainty.
Since the cooling water from the turbocharger cooling water passage
148
a
is first supplied to the turbocharger
140
to cool the turbocharger
140
and is then supplied to the exhaust system (exhaust pipe
27
a
, backflow preventing chamber
27
b
, water muffler
27
c
, exhaust and drain pipe
27
d
) provided on the downstream with respect to the turbocharger
140
in the exhaust system for the engine
20
, the turbocharger
140
can be cooled with cooling water in a state wherein the temperature is the lowest.
Accordingly, the turbocharger
140
can be cooled further efficiently and sufficiently.
Further, also the exhaust system provided downstream with respect to the turbocharger
140
can be cooled.
Since the cooling water having cooled the turbocharger
140
is discharged to the outside of the vessel
10
together with exhaust gas after it is supplied to the exhaust pipe
27
a
provided downstream with respect to the turbocharger
140
in the exhaust system, the exhaust gas which has driven the turbocharger
140
is further cooled in the exhaust pipe
27
a.
In other words, the exhaust gas is cooled in the turbocharger
140
and the exhaust pipe
27
a
. Thus, the exhaust gas energy can be reduced synergetically, and as a result, the exhaust noise can be reduced.
Oil is supplied to the turbocharger
140
and the supplied oil is used to lubricate the bearing portion
142
of the turbocharger
140
and is supplied to the oil jacket
146
formed in the bearing casing
141
to cool the bearing casing
141
. Thus, the turbocharger
140
is cooled even better.
The engine
20
is provided in the body
11
formed from the hull
14
and the deck
15
and the turbocharger
140
is provided for the engine
20
and the oil exits
146
a
,
146
b
of the turbocharger
140
are disposed higher than the oil surface O
1
when the engine stops. If the engine
20
is stopped (accordingly if the operation of the oil pump
80
is stopped), then the oil in the turbocharger
140
is discharged quickly from the oil exits
146
a
,
146
b.
If oil resides in the turbocharger
140
which has a high temperature immediately after the engine stops, then the resident oil is liable to be carbonized, and as a result, there is a problem that the entire oil which circulates in the engine
20
is liable to be degraded. However, with the personal watercraft
10
in which the engine with a turbocharger of the present embodiment is incorporated, if the engine
20
stops, then oil in the turbocharger
140
is discharged rapidly from the oil exits
146
a
,
146
b
, the oil which may reside in the turbocharger
140
after the engine stops can be minimized to reduce the degradation of all of the oil.
Since the engine
20
is a dry sump type engine and the oil tank
50
is provided on an extension line of the crankshaft thereof, the oil surface O
1
when the engine stops can be set to be low.
Accordingly, oil in the turbocharger
140
is discharged quickly from the oil exits
146
a
,
146
b
, and as a result, the deterioration of the entire oil is further reduced.
Since the one-way valve
147
is interposed in each of the oil returning passages
25
b
,
25
c
is in communication with the oil exits
146
a
,
146
b
of the turbocharger
140
, when the personal watercraft
10
capsizes, a situation wherein oil reversely flows from the oil pan
28
to the turbocharger
140
which is in a high temperature state and resides in the turbocharger
140
is eliminated.
Accordingly, carbonization of oil can be prevented with a higher degree of certainty, and degradation of all of the oil can be reduced with a higher degree of certainty.
Since the turbocharger
140
and an end portion of the main gallery
20
a
for oil is provided in parallel to the crankshaft
21
of the engine
20
that are in communication with each other by the oil supply passage
25
a
, oil to the turbocharger
140
is supplied from the end portion of the main gallery
20
a
to the turbocharger
140
directly through the oil supply passage
25
a.
Accordingly, the time until oil is supplied to the turbocharger
140
after the engine is started is reduced. Thus, a quick and reliable operation of the turbocharger
140
can be achieved.
Since the oil pump
80
is provided on the front side of the body
11
with respect to the engine
20
while the turbocharger
140
is provided on the rear side of the body
11
and the turbocharger
140
and the rear end portion of the main gallery
20
a
are in communication with each other by the oil supply passage
25
a
, oil can be supplied rapidly to the turbocharger
140
rearwardly of the engine.
Since oil supplied to the turbocharger
140
is used to lubricate the bearing portion
142
of the turbocharger
140
and is supplied to the oil jacket
146
formed in the bearing casing
141
to cool the bearing casing
141
, not only can the bearing portion
142
of the turbocharger
140
be lubricated but also the bearing casing
141
can be cooled.
Further, where lubrication of the bearing portion
142
of the turbocharger
140
and cooling of the bearing casing
141
are performed with oil supplied to the turbocharger
140
in this manner, it is necessary to quickly supply a greater amount of oil than ever to the turbocharger
140
. However, with the turbocharger cooling structure
10
for a personal watercraft of the present embodiment, since the oil to the turbocharger
140
is supplied from the end portion of the main gallery
20
a
directly to the turbocharger
140
through the oil supply passage
25
a
, a greater amount of oil can be supplied rapidly.
While an embodiment of the present invention is described above, the present invention is not limited to the embodiment described above but can be carried out suitably in various forms within the scope of the subject matter of the present invention.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
Claims
- 1. A turbocharger arrangement structure for a personal watercraft comprising:a hull and a deck forming a watertight personal watercraft; an opening formed in said deck; a lid member for closing said opening to form a body internal space; an intake duct for introducing atmospheric air from outside said body is provided in said space; and an engine and a turbocharger connected to an exhaust manifold of said engine are provided in said space; wherein said turbocharger is disposed higher than a body internal opening of said intake duct.
- 2. The turbocharger arrangement structure for a personal watercraft according to claim 1, wherein a water jacket is formed in a casing of a turbine portion of said turbocharger and an oil jacket is formed in a bearing casing of said turbocharger, and cooling water is supplied to said water jacket and cooling oil is supplied to said oil jacket.
- 3. The turbocharger arrangement structure for a personal watercraft according to claim 2, wherein the cooling water to said water jacket is supplied by a distinct turbocharger cooling water passage independent of any other cooling water passage.
- 4. The turbocharger arrangement structure for a personal watercraft according to claim 2, wherein cooling water is supplied to the turbocharger directly without an intervention from any other cooling devices.
- 5. The turbocharger arrangement structure for a personal watercraft according to claim 2, wherein cooling water is connected to a water jacket of an exhaust pipe for cooling the exhaust pipe.
- 6. The turbocharger arrangement structure for a personal watercraft according to claim 1, wherein mounting said turbocharger at a higher position relative to the internal opening of the intake duct prevents the turbocharger from being exposed to water droplet in the atmospheric air.
- 7. The turbocharger arrangement structure for a personal watercraft according to claim 1, wherein said turbocharger is positioned to the rear of the engine.
- 8. A turbocharger arrangement structure for a personal watercraft comprising:a hull and a deck forming a watertight personal watercraft; an opening formed in said deck; a lid member for closing said opening to form a body internal space; an intake duct for introducing atmospheric air from outside said body is provided in said space; and an engine operatively mounted within said space for propelling said watercraft; an exhaust manifold for said engine; and a turbocharger operatively connected to the exhaust manifold of said engine, said turbocharger being mounted to a rear portion of the engine; wherein said turbocharger is disposed higher than a body internal opening of said intake duct.
- 9. The turbocharger arrangement structure for a personal watercraft according to claim 8, wherein a water jacket is formed in a casing of a turbine portion of said turbocharger and an oil jacket is formed in a bearing casing of said turbocharger, and cooling water is supplied to said water jacket and cooling oil is supplied to said oil jacket.
- 10. The turbocharger arrangement structure for a personal watercraft according to claim 9, wherein the cooling water to said water jacket is supplied by a distinct turbocharger cooling water passage independent of any other cooling water passage.
- 11. The turbocharger arrangement structure for a personal watercraft according to claim 9, wherein cooling water is supplied to the turbocharger directly without an intervention from any other cooling devices.
- 12. The turbocharger arrangement structure for a personal watercraft according to claim 9, wherein cooling water is connected to a water jacket of an exhaust pipe for cooling the exhaust pipe.
- 13. The turbocharger arrangement structure for a personal watercraft according to claim 8, wherein mounting said turbocharger at a higher position relative to the internal opening of the intake duct prevents the turbocharger from being exposed to water droplet in the atmospheric air.
Priority Claims (1)
Number |
Date |
Country |
Kind |
2001-219321 |
Jul 2001 |
JP |
|
US Referenced Citations (5)
Foreign Referenced Citations (2)
Number |
Date |
Country |
10-252440 |
Sep 1998 |
JP |
2001-140641 |
May 2001 |
JP |