JPH05195769A - Silencer device of forcedly air-cooled engine - Google Patents

Abstract

PURPOSE:To enhance the filling efficiency of an engine of sound insulation type. CONSTITUTION:The body 8 of a forcedly air-cooled engine 1, centrifugal cooling fan 14, air cleaner 25, and muffler 27 are accommodated in a sound insulation case 2. A fan case 15 of a cooling fan 14 is installed in front of the crank case 9 of engine body 8. The sound insulation case 2 is partitioned by two partition walls 21, 22 into a body accommodation chamber 24 in the central part about the direction left and right, a cleaner accommodation chamber 26 in the lefthand part, and a muffler accommodation chamber 28 in the righthand part. The engine body 8 is accommodated in the body accommodation chamber 24 while the air cleaner 25 is accommodated in the cleaner chamber 26, and the muffler 27 is accommodated in the muffler accommodation chamber 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a soundproof device for a forced air cooling engine.

[0002]

2. Description of the Related Art In general, this type of soundproof device is constructed as follows. The engine body, centrifugal cooling fan, air cleaner, and muffler are covered with a soundproof case, and the cooling air generated by the cooling fan is configured to flow to the cylinder and cylinder head of the engine body.The muffler is covered with a muffler cover. It is covered.

[0003]

The above-described conventional structure is excellent in that the radiant heat from the muffler can be suppressed from being transmitted to the periphery of the air cleaner by the muffler cover, but it has the following problems. That is, the cooling air is heated by the cylinder, the cylinder head, and the muffler, and the cooling air goes around the air cleaner. Therefore, the intake air that passes through the air cleaner is heated, and the charging efficiency of the engine decreases. The present invention aims to increase the charging efficiency of a soundproof engine.

[0004]

In order to achieve the above object, the present invention has the following structure, for example, as shown in FIGS.

(Invention of Claim 1) The engine body 8 of the forced air cooling engine 1, the centrifugal cooling fan 14, the air cleaner 25 and the muffler 27 are housed in the soundproof case 2, and the front side of the crankcase 9 of the engine body 8 is housed. In a soundproofing device for a forced air-cooled engine, the fan case 15 of the cooling fan 14 is provided in the above, and the cooling air generated by the cooling fan 14 is made to flow through the cylinder 10 and the cylinder head 11 by the fan case 15. The soundproof case 2 is divided into at least two main body housing chambers 24 at the center in the left-right direction, a cleaner housing chamber 26 at one side in the left-right direction, and a muffler housing chamber 28 at the other side in the left-right direction. The partition walls 21 and 22 are provided, the engine main body 8 is accommodated in the main body accommodation chamber 24, and the air is accommodated in the cleaner accommodation chamber 26. Accommodates Lina 25 was constructed by accommodating the muffler 27 in the muffler housing chamber 28.

(Invention of Claim 2) In the structure of Claim 1, the main body accommodating chamber 24 is provided with a main body accommodating chamber outlet 33.
The muffler chamber 28 is communicated with the atmosphere through the muffler chamber outlet 34.

(Invention of Claim 3) The above Claim 1 or 2
In the above configuration, the forced air cooling engine 1 includes the electronic governor 19, and the electronic control unit 19 of the electronic governor 19 is provided.
a and the fuel control electric motor 19b are connected to the cleaner accommodating chamber 2
Housed in 6.

[0008]

The present invention operates as follows. Cooling fan 14
The cooling air discharged from the fan case 15 cools and heats the cylinder 10 and the cylinder head 11 while flowing in the main body accommodation chamber 24 partitioned by the cleaner-side partition wall 21 and the muffler-side partition wall 22. The heated cooling air is discharged to the outside of the soundproof case 2.

The cleaner side partition wall 21 prevents the heated cooling air from flowing into the cleaner accommodating chamber 26. Further, the cleaner accommodating chamber 26,
Since the main housing chamber 24 is located on the opposite side of the muffler housing chamber 28 from the muffler housing chamber 28, the radiant heat of the muffler 27 is transferred to the cleaner housing chamber 2.
The heating of 6 can be prevented.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described below with reference to the drawings. FIG. 1 is a cross-sectional plan view, and FIGS. 2 to 4 are II- of FIG.
FIG. 11 is a sectional view taken along the line II, the line III-III, and the line IV-IV.

The forced air cooling engine 1 is a vertical gasoline engine and is housed in a soundproof case 2. In FIG. 1, reference symbol F indicates the front side, reference symbol B indicates the rear side, reference symbol L indicates the left side, and reference symbol R indicates the right side. The soundproof case 2 is constructed by assembling a front case part 4, a right case part 5 and a rear case part 6 to a base plate 3.
The sound absorbing material 7 is attached to the inner peripheral surfaces of the case portions 4, 5 and 6.

As shown mainly in FIG. 3, an engine body 8 housed in the central portion of the soundproof case 2 is fixed to the base plate 3, and a cylinder 10 and a cylinder head 11 are provided above a crankcase 9 of the engine body 8. And the head cover 12 are fixed in order. Further, as shown in FIGS. 1 and 2, the fan case 15 of the centrifugal cooling fan 14 is fixed to the front side of the crankcase 9. An impeller (not shown) of the cooling fan 14 is fixed to the front end portion of the crankshaft 16. The air guide cover 17 is led out rearward from the upper right portion of the fan case 15. The carburetor 18 is fixed to the left front part of the cylinder head 11, and the electronic governor 19 is fixed to the left rear part of the crankcase 9. The electronic governor 19 includes an electronic control unit 19a.
And a fuel control electric motor 1 including a solenoid or a motor
9b and.

The soundproof case 2 includes a main body housing chamber 24 for housing the engine main body 8 and the electronic governor 19 by left and right partition walls 21 and 22 extending in the front-rear direction.
And a cleaner accommodating chamber 26 accommodating the air cleaner 25
And a muffler storage chamber 28 that stores the muffler 27 in the left-right direction. The cleaner-side partition wall 21 and the muffler-side partition wall 22 are detachably fixed to the outer surface of the engine body 8.

A cooling air inlet 31 is formed in the lower left portion of the rear case portion 6. The cooling air outlet 32 comprises a main body accommodation chamber outlet 33 formed in the upper right portion of the rear case portion 6 and a muffler accommodation chamber outlet 34 formed in the upper right portion of the right case portion 5. Both of these outlets 33 and 34 are communicated with the outside of the soundproof case 2. As shown in FIG. 3, the exhaust pipe 36 is led out rearward from the rear portion of the cylinder head 11 and connected to the muffler 27. The muffler 27
An outlet pipe 38 is bent backward from the front of the muffler body 37, and the rear end of the outlet pipe 38 faces the outlet 34 of the muffler accommodating chamber. The muffler body and the outlet pipe 38 are covered with a heat insulating material 39.

A cooling air introduction passage 41 is defined by the left partition plate 40 below the cleaner accommodating chamber 26. As shown in FIG. 2 and FIG. 4, the case front wall 43 of the front case portion 4 is located in front of the air intake port 42 of the fan case 15.
The front wall portion 44 of the air suction chamber bulges forward from the lower half portion.
An air suction chamber 47 is formed by the front partition plate 46 between the air suction chamber front wall portion 44 and the air suction port 42. An engine control panel 49 is provided on the upper half of the case front wall 43. The operation panel 49 is attached to the operation panel 49 in a state of being displaced to the rear side of the air suction chamber front wall portion 44 that bulges below.

The cleaner housing 51 of the air cleaner 25 is fixed to the left end of the carburetor 18.
The cleaner element 52 is inserted in the lower part of the housing 51, and the baffle plate 5 is inserted in the upper part thereof.
3 is provided, and two intake muffling chambers 54 and 55 are formed above and below the plate 53. The air intake port 56 formed on the lower surface of the housing 51 has the cooling air introduction passage 41.
Be communicated to.

As shown in FIGS. 1 and 2, a spark plug mounting hole 60 is opened in the upper right portion of the air guide cover 17 so as to face the muffler side partition wall 22. A spark plug insertion hole 61 is opened in the muffler-side partition wall 22 so as to face the spark plug mounting hole 60. The cylinder head 1
The spark plug 62 fixed to No. 1 is the spark plug insertion hole 61 and the spark plug mounting hole 60 from the muffler chamber 28.
And are inserted in order. The spark plug cap 63 connected to the spark plug 62 is sequentially inserted from the muffler accommodating chamber 28 into the spark plug insertion hole 61 and the spark plug mounting hole 60. Further, ventilation gaps 68 and 69 are provided between the respective inner peripheral surfaces of the spark plug assembly hole 60 and the spark plug insertion hole 61 and the spark plug cap 63.

When the cooling fan 14 is operated in accordance with the operation of the engine 1, the airflow of the cooling fan 14 causes air to flow in the soundproof case 2 as indicated by the arrow in each figure. As shown mainly in FIG. 1, the air outside the soundproof case 2 is sucked into the air intake port 42 of the fan case 15 through the cooling air inlet 31, the cooling air introduction passage 41, and the air intake chamber 47 in order, and from here. It is circulated to the cylinder 10 and the cylinder head 11 through the air guide cover 17 and sent to the rear part of the main body accommodation chamber 24, and then discharged from the main body accommodation chamber outlet 33 provided in the rear case portion 6 to the outside of the soundproof case 2.

Further, as shown in FIGS. 2 and 4, a part of the cooling air flowing through the cooling air introduction passage 41 is introduced from the air intake port 56 of the air cleaner 25 to the cleaner element 52 and the intake and silencer chambers 54 and 55. Carburetor 18
Is sucked into the air inlet 71. Furthermore, mainly in FIG.
As shown in FIG. 5, a part of the cooling air flowing in the air guide cover 17 is discharged to the muffler accommodation chamber 28 through the ventilation gaps 68 and 69 in order, and passes through the muffler accommodation chamber 28. Then, the muffler accommodation chamber outlet 34 is discharged to the outside of the soundproof case 2.

The soundproof engine 1 is mainly assembled in the following procedure. First, the engine body 8 is fixed to the base plate 3, and the left and right partition walls 21 and 22 are attached to the engine body 8. Then the base plate 3
The lower part of the front case part 4 and the lower part of the rear case part 6 are inserted into the gap between the wall part 3a and the lower grip 73 provided on the upper part and fixed by friction, and at the same time, the left rear end part of the front case part 4 is fixed. Insert the left grip 74 of the rear case portion 6 into the inner surface. Finally, the left end portion of the right case portion 5 is inserted into the right grip 75 of the front case portion 4 and the right grip 76 of the rear case portion 6 and fixed by friction. At this time, as shown in the rear view of FIG. 3, the U-shaped metal fitting 77 provided on the right case part 5
Is configured to fit into the locking portion 78 of the muffler side partition wall 22. In order to improve the appearance, the right case portion 5 is provided with fin-shaped portions 79 which are connected to the front and rear surfaces and the upper surface. Reference numeral in FIG. 3 above is the starter motor 80.
Is.

The above embodiment can be modified as follows. The engine 1 may be a gas engine, a diesel engine, or a horizontal engine. Further, the engine 1 can also be formed in a shape in which the air cleaner 25 and the muffler 27 are arranged left and right. The heat insulating material 39 of the muffler 27 may be omitted. In this case, it is preferable that the muffler body 37 is provided with a muffler cover with a predetermined gap.

[0022]

The present invention has the following effects because it is constructed and operates as described above. (Invention of Claim 1) It is possible to prevent the cooling air heated by the cylinder and the cylinder head from flowing into the cleaner accommodating chamber by the cleaner side partition wall, and it is located on the opposite side of the muffler accommodating chamber with the main body accommodating chamber interposed therebetween. It is difficult for heat from the muffler to be transferred to the cleaner storage chamber. Therefore, the air cleaner in the cleaner housing chamber is prevented from being heated. As a result, the filling efficiency of the engine is increased.

To achieve the above effect, it is only necessary to partition the inside of the soundproof case by the two partition walls. As a result, the soundproof case described above can be manufactured at a low cost with a simple structure by omitting a complicated ventilation passage and can be made compact.

(Invention of Claim 2) The cooling air discharged from the main body accommodating chamber to the outside of the soundproof case is directly discharged from the main body accommodating chamber outlet to the atmosphere and does not have to pass through the muffler accommodating chamber.
For this reason, the exhaust air resistance of the main body accommodation chamber is reduced,
The cylinder and cylinder head can be cooled sufficiently.

(Invention of Claim 3) As described above, since the electronic control unit of the electronic governor and the electric motor for fuel control are accommodated in the cleaner accommodating chamber which is prevented from being heated by the cylinder, the cylinder head and the muffler, these electronic controls are performed. It is possible to prevent the device and the fuel control motor from overheating. As a result, the reliability of the electronic governor is enhanced.

[Brief description of drawings]

FIG. 1 is a cross-sectional plan view of a soundproof type forced air cooling engine.

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

3 is a sectional view taken along the line III-III of FIG.

FIG. 4 is a sectional view taken along the line IV-IV of FIG.

[Explanation of symbols]

1 ... Engine, 2 ... Soundproof case, 8 ... Engine body, 9
... crank case, 10 ... cylinder, 11 ... cylinder head, 14 ... cooling fan, 15 ... fan case, 19 ...
Electronic governor, 19a ... Electronic control device, 19b ... Fuel control electric motor, 21 ... Cleaner side partition wall, 22 ... Muffler side partition wall, 24 ... Main body accommodating chamber, 25 ... Air cleaner, 26 ...
Cleaner chamber, 27 ... muffler, 28 ... muffler chamber, 3
3 ... Main body accommodation chamber outlet, 34 ... Muffler accommodation chamber outlet.

Claims (3)

[Claims] 1. An engine body of a forced air cooling engine (1)
(8) -Centrifugal cooling fan (14) -Air cleaner (25)
The muffler (27) is housed in the soundproof case (2), and the fan case (15) of the cooling fan (14) is provided in front of the crankcase (9) of the engine body (8) to cool the cooling system. The cooling air generated by the fan (14) is used for the above fan case.
Cylinder (10) and cylinder head (1
In a soundproof device for a forced air-cooled engine, which is configured to be circulated in 1), in the soundproof case (2), a main body housing chamber (24) at a central part in the left-right direction and a cleaner housing at one side part in the left-right direction are housed. At least two partition walls (21) partitioning the chamber (26) and the muffler accommodating chamber (28) on the other side in the left-right direction
(22) is provided to accommodate the engine body (8) in the main body accommodating chamber (24), the air cleaner (25) in the cleaner accommodating chamber (26), and the muffler accommodating chamber (28).
A soundproof device for a forced air-cooled engine, characterized in that the muffler (27) is housed inside. 2. The soundproofing device for a forced air-cooled engine according to claim 1, wherein the main body housing chamber (24) is configured to communicate with the atmosphere through a main body housing chamber outlet (33), The muffler storage chamber (28) has an outlet (34) for the muffler storage chamber.
It is constructed by communicating with the atmosphere through. 3. The soundproof device for a forced air cooling engine according to claim 1, wherein the forced air cooling engine (1) includes an electronic governor (19), and an electronic control unit (19a) for the electronic governor (19). ) And the fuel control electric motor (19b) are connected to the cleaner accommodating chamber (26).
Housed in.