JP2000282899A - Two-cycle engine and ship mounted with the two-cycle engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To position an exhaust control valve and the pulley of a servo motor before installing the servo motor and the exhaust control valve, without using a jig and the like which are originally unnecessary. SOLUTION: A water jacket is provided in the exhaust manifold 80 of a two-cycle engine which is to be carried on a ship, and an exhaust control valve and a servo motor 110 are mounted on the exhaust manifold 80. The water jacket is supplied directly with cooling water from a jet pump. An adjuster 122 is mounted on the exhaust manifold 80 through a bracket 123.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-stroke engine and a ship on which the two-stroke engine is mounted.

[0002]

2. Description of the Related Art Some conventional two-stroke engines include:
It is known that an exhaust control valve is provided at an exhaust port of a cylinder, and the opening degree of the exhaust port, that is, the exhaust timing is changed by the exhaust control valve to improve the output from a low rotation range to a high rotation range. .

FIG. 8 is a view showing an example of the two-stroke engine, in which (a) is a schematic diagram for explaining the structure, and (b) is a partial perspective view.

In the two-cycle engine 200, an exhaust control valve 220 is provided at an exhaust port 211 of a cylinder 210. The exhaust control valve 220 is operated by a servo motor 230 via a cable 240.

More specifically, the shaft 22 of the exhaust control valve 220
1 and a lever 222 is fixed to the lever 222.
Are both ends 241 of a cable 240 connected to a pulley 231 that is rotationally driven by a servomotor 230.
241.

Therefore, when the pulley 231 rotates by the operation of the servo motor 230, the lever 222 rotates, and the shaft 2
21 and the exhaust control valve 220 rotate to change the opening degree of the exhaust port 221, that is, the exhaust timing.

Adjusters 242 and 242 are provided near both ends 241 and 241 of the cable 240.
The position adjustment between the pulley 231 of the servomotor 230 and the exhaust control valve 220 can be performed using these adjusters 242 and 242.

The operation of the servo motor 230 is controlled by the control unit 250. The control unit 250 detects the engine speed based on the signal from the CDI unit 251, detects the opening of the exhaust control valve 220 using a potentiometer (not shown) in the servomotor 230, and responds to the engine speed. The servomotor 230 is operated according to the valve opening.

On the other hand, as a conventional ship, a ship equipped with a two-cycle engine and having a jet pump as propulsion means driven by the engine is known. 2
The cycle engine is relatively small and can be expected to have a high output, and is therefore particularly mounted on small vessels.

[0010]

In the above-described conventional two-stroke engine, the servomotor 230 is controlled by the exhaust control valve 22.
The mounting member 260 is attached to a different mounting member 260 from the member to which the “0” is attached (in this case, the cylinder block 210).

For this reason, before the servo motor 230 is mounted by the mounting member 260, the exhaust control valve 220 and the pulley 231 of the servo motor 230 are previously positioned using the adjuster 242 (this positioning is referred to as pre-positioning). ), The difference between the bent state of the cable 240 at the time of the pre-positioning and the bent state of the cable 240 when the servomotor 230 is actually mounted by the mounting member 260 causes the pre-positioning. There is a problem that the setting of the exhaust control valve 220 is displaced between the time when the assembly is completed and the time when the assembly is completed, so that the original engine performance cannot be exhibited.

In order to solve this problem, the pre-positioning must be performed using a jig or the like in which the cable 240 is in the same state as the assembly completed state. In addition, another problem arises in that the pre-positioning operation using the jig or the like becomes complicated. In addition, it is not desirable to position the exhaust control valve 220 and the pulley 231 of the servomotor 230 after the completion of the assembly of the engine because the operation becomes more complicated.

An object of the present invention is to provide a two-stroke engine capable of solving the above problems and performing the pre-positioning without using an originally unnecessary jig or the like, and a ship equipped with the two-stroke engine. It is in.

[0014]

According to a first aspect of the present invention, there is provided a two-cycle engine, comprising: an exhaust control valve for adjusting an opening of an exhaust port of a cylinder; and a servomotor for operating the exhaust control valve. And a two-cycle engine interlocked via a cable, wherein the exhaust control valve and the servomotor are mounted on the same member.

A two-stroke engine according to a second aspect of the present invention is the two-stroke engine according to the first aspect, wherein the same member is an exhaust manifold having a water jacket.

A two-stroke engine according to a third aspect of the present invention is the two-stroke engine according to the second aspect, wherein the water jacket is directly supplied with cooling water from a cooling water supply source.

The ship according to the fourth aspect is the ship according to the third aspect.
A ship equipped with a cycle engine and having a jet pump as propulsion means driven by the engine, wherein cooling water is directly supplied from a jet pump as a cooling water supply source to a water jacket of the exhaust manifold. It is characterized by.

[0018]

In the two-stroke engine according to the first aspect, the exhaust control valve for adjusting the opening of the exhaust port of the cylinder and the servomotor for operating the exhaust control valve are interlocked via a cable. By operating the exhaust control valve via a cable by operating the servomotor and adjusting the opening of the exhaust port of the cylinder, it is possible to improve the output from a low rotation range to a high rotation range.

Since the exhaust control valve and the servomotor are mounted on the same member, the pre-positioning can be performed by using this member (the same member). There will be no deviation in the setting of the exhaust control valve between the time when the assembly is completed and the time when the assembly is completed.

That is, according to the two-stroke engine of the first aspect, the pre-positioning can be performed without using an originally unnecessary jig or the like, and as a result, the assemblability of the engine is improved. Will be done.

According to the two-stroke engine of the second aspect, in the two-stroke engine of the first aspect, the same member is an exhaust manifold having a water jacket. Prepositioning can be performed.

By the way, since the exhaust manifold becomes extremely hot when the engine is operating, it is generally impossible to attach a servo motor as an electric component that dislikes high temperature to this exhaust manifold (at least, desirably). No).

On the other hand, according to the two-stroke engine of the present invention, since the exhaust manifold has the water jacket, the temperature rise of the exhaust manifold is significantly reduced by the action of the water jacket. Becomes

Therefore, a servomotor (and an exhaust control valve) can be attached to the exhaust manifold, and the pre-positioning can be performed using the exhaust manifold.

According to the two-stroke engine of the third aspect, in the two-stroke engine of the second aspect, the cooling water is directly supplied from a cooling water supply source to the water jacket. Thus, the temperature rise of the exhaust manifold can be more reliably reduced.

Therefore, the servo motor (and the exhaust control valve) can be more reliably attached to the exhaust manifold, and the pre-positioning can be more reliably performed using the exhaust manifold.

The ship according to the fourth aspect is the ship according to the third aspect.
Since a cycle engine is mounted and has a jet pump as propulsion means driven by this engine,
Propelled by the action of this jet pump.

The cooling water is directly supplied to the water jacket of the exhaust manifold of the engine from the jet pump as a cooling water supply source.
The rise in the temperature of the exhaust manifold can be further reduced.

More specifically, since the jet pump is driven by the engine, as the engine speed increases (as the temperature of the exhaust manifold increases), the jet pump moves from the jet manifold to the water jacket of the exhaust manifold. A large amount of cooling water is directly supplied. Therefore, the exhaust manifold is appropriately cooled according to the engine speed.

In addition, there is no need to provide a water pump for supplying cooling water to the water jacket in addition to the jet pump.

That is, according to the marine vessel of the fourth aspect, it is possible to more reliably attach the servo motor (and the exhaust control valve) to the exhaust manifold without providing a water pump other than the jet pump.
The pre-positioning can be more reliably performed using the exhaust manifold.

[0032]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a partially cut-away schematic side view showing an embodiment of a two-stroke engine according to the present invention and a ship on which the two-stroke engine is mounted, FIG. 2 is a sectional view taken along the line II-II in FIG.
3 is a sectional view showing an embodiment of the two-stroke engine according to the present invention, FIG. 4 is a front view thereof, FIG. 5 is a partially enlarged view of FIG. 4, and FIG. 6 is a sectional view taken along the line VI-VI in FIG. 7
(A), (b) is a figure which shows a cooling path, respectively.

As shown in FIGS. 1 and 2, a boat 1 of this embodiment is a small boat of a saddle type, in which an occupant sits on a seat 2 on a hull 10 and a steering wheel 3 with a throttle grip is provided. It can be operated by grasping.

The hull 10 has a floating structure in which a lower hull panel 11 and an upper hull panel 12 are joined to form a space 13 therein. In the space 13, an engine 20 is mounted on the lower hull panel 11 via a boss 11a, a mounting block 14, and an engine hanger 15 and a jet pump 30 driven by the engine 20 is provided at a rear portion of the lower hull panel 11. ing.

The jet pump 30 has a flow path 35 extending from an intake port 31 opened at the bottom of the ship to a jet nozzle 32 opened at the rear end of the hull, and an impeller 33 disposed in the flow path.
The shaft 34 of the impeller 33 is connected to the output shaft 21 of the engine 20. Therefore, when the impeller 33 is rotationally driven by the engine 20, the water taken in from the water intake 31 is jetted from the jet nozzle 32, and the hull 10 is propelled by this.

In FIG. 1, reference numeral 4 denotes a fuel tank,
a is the fuel supply port. In FIG. 2, reference numeral 12a denotes a footrest, and 16 denotes a buoyant body made of a foam or the like.

As shown in FIG. 3, the engine 20 is a parallel multi-cylinder two-cycle engine having a crankcase 40, a cylinder block 50, and a cylinder head 60, and includes a crankcase 4 formed by the crankcase 40.
Fresh air is sucked into the fuel cell 1 via a reed valve 42, and the fresh air is supplied to a combustion chamber 61 formed between the cylinder head 60 and the piston P via a scavenging passage 51 for combustion. Upstream of the intake passage 43 where the reed valve 42 is provided,
An air cleaner 45 is provided via an intake pipe 44 (see FIG. 2). The two-cycle engine 20 is of an air scavenging type in which fresh air sucked into the crank chamber 41 is only air, and fuel is supplied to the combustion chamber 61 separately from air.

Numeral 70 denotes a fuel injection device as a fuel supply means, which is a rotary valve 71 which opens and closes a fuel injection port 52 formed on the inner surface of the cylinder block 50, and which is connected to the fuel injection port 52 through the rotary valve 71. A pressure accumulating chamber 72 that can communicate with the fuel, a fuel reservoir passage 73 that communicates with the pressure accumulating chamber 72 and can communicate with the fuel injection port 52 via the rotary valve 71, and an appropriate amount of fuel is measured in the fuel reservoir passage 73. And a fuel injector 74 for injecting fuel.

The rotary valve 71 has a shallow groove-shaped communication path 71a partially (over about 180 °) in the circumferential direction, and is synchronized with the crankshaft 46 and is opposite to the crankshaft 46. Rotate in the direction (counterclockwise in the figure). Specifically, as shown in FIG.
6 is provided with a sprocket S1 and a rotary valve 71 is provided.
A sprocket S2 is provided at a shaft end 71b of the sprocket S2.
A chain T is provided via idle sprockets S3 and S4 for reversing the rotation direction of S2.

The operation of the engine will be briefly described.

FIG. 3 shows a state at the end of the scavenging step. In this state, when the piston P enters an intake process in which the piston P moves upward in the drawing, the reed valve 42 opens, and fresh air is introduced into the crank chamber 41 via the air cleaner 45 and the intake pipe 44. Further, the piston P moves upward and enters a compression process,
When the exhaust port 53 is closed (or substantially closed) by the piston P, the communication path 7 of the rotary valve 71 is closed.
1 a communicates the fuel reservoir passage 73 with the fuel injection port 52, and the fuel injected into the fuel reservoir passage 73 as described later by the high-pressure gas filled in the accumulator chamber 72 as described later. The fuel is injected from the fuel injection port 52 into the cylinder. Thereafter, when the piston P further moves upward and is ignited by the ignition plug 62 of the cylinder head 60 and enters the explosion expansion step, the piston P moves downward when the piston P moves downward.
After the fuel injection port 52 is opened by passing through the fuel injection port 52, the communication passage 71a of the rotary valve 71 communicates the fuel injection port 52 with the pressure accumulation chamber 72, and the pressure accumulation chamber 72 is filled with high-pressure gas. You. The injection of the appropriate amount of fuel into the fuel reservoir 73 by the fuel injector 74 is performed after the fuel injection and before the fuel injection is performed again. Thereafter, when the exhaust port 53 is opened by further lowering the piston P, exhaust is performed,
Thereafter, when the scavenging port 54 is opened by further downward movement of the piston P, scavenging is performed, the state returns to the state shown in FIG. 3, and the above-described operation is repeated.

As shown in FIG. 3, the exhaust port 53 is provided with an exhaust manifold 80 connected thereto, and further downstream thereof is provided an exhaust chamber 91 via an exhaust pipe 90 (see FIG. 2). ing.

The exhaust port 53 has an opening of 0 to 10
An exhaust control valve 55 adjustable between 0% is provided, and a shaft 56 serving as a rotation center of the exhaust control valve 55 is provided in the exhaust manifold 80. That is, the exhaust control valve 55 is attached to the exhaust manifold 80.

As shown in FIGS. 4 to 6 (mainly FIGS. 5 and 6), the end 56a of the shaft 56 projects from the outer peripheral surface of the exhaust manifold 80, and a lever 58 is attached to the shaft end 56a.
Has been fixed.

At the bottom of the exhaust manifold 80,
The servomotor 110 is attached with bolts 111 and 112. The output shaft of the servomotor 110 has a pulley 1
13 are provided, and pins 121, 121 at both ends of the cable 120 connected to the pulley 113 are connected to both ends of the lever 58.

Therefore, when the pulley 113 rotates by the operation of the servomotor 110, the lever 58 rotates, and the shaft 56 rotates.
Then, the exhaust control valve 55 is rotated, and the opening degree of the exhaust port 53, that is, the exhaust timing is changed.

Adjusters 122, 122 are provided near both ends of the cable 120, and the position adjustment between the pulley 113 of the servomotor 110 and the exhaust control valve 56 is performed by using the adjusters 122, 122. It is possible. The adjusters 122, 122 are mounted on a bracket 123, and the bracket 123 is mounted on the outer peripheral surface of the exhaust manifold 80 with three bolts 124 (see FIGS. 4 and 6).

The operation of the servomotor 110 is controlled by a control unit (not shown). The control unit detects the engine speed based on a signal from a CDI unit (not shown).
The opening of the exhaust control valve 55 is detected by a potentiometer (not shown) in the servomotor 110, and the servomotor 110 is operated at a valve opening corresponding to the engine speed.

As shown in FIG. 3, the cylinder head 60 is provided with a thermostat 63 which operates according to the water temperature of a water jacket, which will be described later.

For example, in the above two-cycle engine, if no measures are taken,
Since the exhaust manifold 80 becomes extremely hot during operation of the engine, it is generally impossible to attach a servo motor 110 as an electric component that dislikes high temperature to the exhaust manifold 80 (at least it is not desirable). ).

Therefore, in the two-stroke engine 20 of this embodiment, a water jacket 81 is provided on the exhaust manifold 80 as shown in FIGS.

Cooling water from the jet pump 30 is supplied to the water jacket 8 at a lower portion outside the exhaust manifold 80.
1 is provided with an introduction pipe 82 for direct introduction into
The cooling water introduced from the introduction pipe 82 cools the exhaust manifold 80 through the water jacket 81 of the exhaust manifold 80, and is then supplied to the water jacket 57 of the cylinder block 50. The water is supplied to the water jacket 64 of the head 60. Cooling water from the water jacket 64 is supplied to the uppermost portion 64 </ b> A of the water jacket 64 of the cylinder head 60 located at the thermostat 63 portion in the exhaust chamber 91.
There is provided a drain pipe 65 for discharging water toward.

In the two-stroke engine 20 of this embodiment, fresh air drawn into the crank chamber 41 is supplied to the combustion chamber 61, so that no measures are taken. Then, the temperature of the crankcase 41 (that is, the crankcase 40) rises and the output decreases. In particular, for example, in the air scavenging type as in this embodiment, since only air is sucked into the crank chamber 41 and the cooling action by the fuel is not obtained, the temperature of the crank chamber 41 easily rises, and Easy to come down.

Therefore, in this embodiment, as shown in FIG. 3, a water jacket 47 for cooling the crankcase 40 is provided. In the crankcase 40 of this embodiment, a lower case 40A and an upper case 40B are joined by bolts 48,
7 is provided over both cases. That is, the water jacket 47A of the lower case 40A and the water jacket 47B of the upper case 40B communicate with each other. An inlet pipe 49A for directly introducing cooling water (seawater or fresh water) from the jet pump 30 into the water jacket 47 is provided at the bottom of the lower case 40A, and the water jacket 47 in the upper case 40B.
B has a water jacket 47B on the top 47B1.
There is provided a drain pipe 49B for discharging the cooling water from the exhaust chamber 91 toward the exhaust chamber 91.

FIG. 7A shows the path of the cooling water as described above.
To explain with reference to (b), the cooling water introduction pipe 10 is inserted into a portion 35a of the flow path 35 of the jet pump 30 between the impeller 33 (see FIG. 1) and the jet nozzle 32.
0 is connected, and the introduction pipe 100 is branched into two pipes 102 and 103 at a branch part 101. One pipe 102 is an inlet pipe 49A of the crankcase 40.
The other pipe 103 is connected to the introduction pipe 82 of the exhaust manifold 80. FIG. 7 (a)
As shown by a two-dot chain line 102 ′ in FIG.
The pipe 102 connected to the introduction pipe 49 </ b> A may be directly connected to the jet pump 30 without branching from the introduction pipe 100. In any case, the cooling water is directly supplied to the water jacket 81 of the exhaust manifold 80 through a supply path 103 different from the supply path 102 of the cooling water to the water jacket 47 of the crankcase 40.

As shown in FIG. 7A, a drain pipe 49B of the crankcase 40 is connected by a pipe 104 to a cooling water introduction pipe 92 communicating with a water jacket (not shown) of the exhaust chamber 91. A pipe 105 is connected to the drain pipe 65 of the cylinder head 60. The pipe 105 joins the pipe 104 at a junction 106 with the pipe 104, and is connected to the introduction pipe 92 of the exhaust chamber 91 via the pipe 104. It is connected. As shown by reference numeral 105 ′ in FIGS. 3 and 7B, the drain pipe 65 of the cylinder head 60 and the inlet pipe 9 of the exhaust chamber 91.
2 means that the pipe 10 does not join the pipe 104
The connection may be made directly at 5 '.

As described above, the cooling water path is divided into two paths. One path is jet pump 30 → introduction pipe 100 (or pipe 102 ′) → pipe 102
→ Introduction pipe 49A → Water jacket 47 (47A, 47B) of crankcase 40 → Drain pipe 49B → Pipe 104 → Wooter jacket of exhaust chamber 91. The other path is the jet pump 30 → introduction pipe 100 → pipe 103 → introduction pipe 82 → water jacket 81 of the exhaust manifold 80 → water jacket 57 of the cylinder block 50 → water jacket 64 of the cylinder head 60 → thermostat 63
Around the water jacket 64A → drain pipe 65 → pipe 105 → pipe 104 (or pipe 105 ') →
This is a route called a water jacket of the exhaust chamber 91.

According to the two-cycle engine 20 as described above, the following operation and effect can be obtained.

(A) Since the exhaust control valve 55 for adjusting the opening of the exhaust port 53 of the cylinder and the servo motor 110 for operating the exhaust control valve 55 are linked via the cable 120, the servo motor 110 By operating the exhaust control valve 55 via the cable 120 and adjusting the degree of opening of the exhaust port 53 of the cylinder by the above operation, it is possible to improve the output from a low rotation range to a high rotation range.

The exhaust control valve 55 and the servo motor 1
10 is mounted on the same member 80, so that it is pre-positioned using this member (the same member) 80, that is, before the servo motor 110 and the exhaust control valve 55 are mounted by the mounting member 80, the adjusters 122, 12
2 can be used to position the exhaust control valve 55 and the pulley 113 of the servomotor 110, and the position of the exhaust control valve 55 can be adjusted between the pre-positioning and the completion of the assembly with the member 80 attached. No deviation occurs in the setting.

That is, according to the two-stroke engine 20 of this embodiment, the pre-positioning can be performed without using an originally unnecessary jig or the like.
As a result, the assemblability of the engine 20 is improved.

(B) Since the same member is an exhaust manifold 80 having a water jacket 81, the pre-positioning can be performed using the exhaust manifold 80.

As described above, if no measures are taken, the exhaust manifold 80 becomes extremely hot when the engine is running. Therefore, the servomotor 110 as an electric component which dislikes high temperature is attached to the exhaust manifold 80. Although it is generally impossible to do so, according to the two-stroke engine 20 of this embodiment, since the exhaust manifold 80 has the water jacket 81,
By the action of the water jacket 81, the temperature rise of the exhaust manifold 80 is significantly reduced.

Therefore, the servo motor 110 (and the exhaust control valve 55) can be attached to the exhaust manifold 80, and the pre-positioning can be performed using the exhaust manifold 80.

(C) Since the cooling water from the jet pump 30 as the cooling water supply source is directly supplied to the water jacket 81 of the exhaust manifold 80, the temperature of the exhaust manifold 80 further increases. It will surely be reduced.

Therefore, it is possible to attach the servo motor 110 (and the exhaust control valve 55) to the exhaust manifold 80 more reliably.
It is possible to more reliably perform the pre-positioning using 0.

(D) Since the water jacket 47 for cooling the crankcase 40 is provided in the crankcase 40,
The temperature rise of the crankcase 40 (that is, the crankcase 41) is significantly reduced, and the temperature rise of fresh air sucked into the crankcase 41 is also significantly reduced. Therefore, the amount of oxygen per unit volume of fresh air increases, so that the combustion efficiency is improved and a high output can be obtained.

(E) Since the two-stroke engine 20 of this embodiment is an air scavenging type, fresh air sucked into the crank chamber 41 is only air, and fresh air from the scavenging passage 51 is supplied to the combustion chamber 61. Fuel is supplied separately from air (air).
Therefore, the fuel efficiency is remarkably improved as compared with the fuel-air mixture scavenging type. That is, according to the two-stroke engine 20 of this embodiment, it is possible to remarkably improve fuel economy and to obtain high output.

(F) Since the water jacket 57 is also provided on the cylinder block 50, a rise in the temperature of the cylinder block 50 is reduced, and a higher output can be obtained.

According to the marine vessel 1 of this embodiment, the following operational effects can be obtained.

That is, the boat 1 of this embodiment is equipped with the two-stroke engine 20 and has the jet pump 30 as propulsion means driven by the engine. Will be promoted.

Since the cooling water is directly supplied to the water jacket 81 of the exhaust manifold 80 of the engine 20 from the jet pump 30 as a cooling water supply source, the temperature rise of the exhaust manifold 80 is further reduced. Will be done.

More specifically, since the jet pump 30 is driven by the engine 20, as the rotation speed of the engine 20 increases (as the temperature of the exhaust manifold 80 tends to increase), the jet manifold 30 is released from the jet pump 30. A large amount of cooling water is supplied directly to the water jacket 81. Therefore, the exhaust manifold 80 depends on the rotation speed of the engine 20.
Is cooled well.

Further, in addition to the jet pump 30, there is no need to provide a water pump for supplying cooling water to the water jacket 81.

That is, according to the boat 1 of this embodiment, the servo motor 110 is connected to the exhaust manifold 80 without providing a water pump in addition to the jet pump 30.
(And the exhaust control valve 55) can be attached more reliably, and the pre-positioning can be more reliably performed using the exhaust manifold 80.

Further, since cooling water is supplied from the jet pump 30 to the water jackets 47, 57, etc. of the engine 20, the crankcase 40, the cylinder block 50, etc. are cooled well and the size and weight are reduced. High output can be obtained.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and can be appropriately modified within the scope of the present invention.

[0079]

[Brief description of the drawings]

FIG. 1 is a partially cut-away schematic side view showing an embodiment of a two-stroke engine according to the present invention and a ship on which the two-stroke engine is mounted.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view showing one embodiment of a two-stroke engine according to the present invention.

FIG. 4 is a front view of the same.

FIG. 5 is a partially enlarged view of FIG. 4;

FIG. 6 is a sectional view taken along the line VI-VI in FIG. 5;

FIGS. 7A and 7B are diagrams each showing a cooling path.

FIG. 8 is a view showing an example of a conventional two-cycle engine.
(A) is a schematic diagram for explaining the structure, and (b) is a partial perspective view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ship 20 2 cycle engine 30 Jet pump 53 Exhaust port 55 Exhaust control valve 80 Exhaust manifold 81 Water jacket 82 Cooling water introduction pipe 110 Servo motor 120 Cable

Claims (4)

[Claims] 1. A two-stroke engine in which an exhaust control valve that adjusts an opening of an exhaust port of a cylinder and a servomotor that operates the exhaust control valve are linked via a cable, wherein the exhaust control valve is provided. And a servomotor are mounted on the same member. 2. The two-stroke engine according to claim 1, wherein the same member is an exhaust manifold having a water jacket. 3. The two-stroke engine according to claim 2, wherein cooling water from a cooling water supply source is directly supplied to the water jacket. 4. A ship equipped with the two-stroke engine according to claim 3 and having a jet pump as propulsion means driven by the engine, wherein a water jacket of the exhaust manifold is provided as a cooling water supply source. A ship to which cooling water is directly supplied from a jet pump.