JP2010007599A - Engine-driven power generator apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an engine-driven power generator apparatus capable of suppressing exhaust noise and intake noise of an engine and reducing the temperature of a case without degrading portability. <P>SOLUTION: The engine-driven power generator apparatus 10 is provided with a first engine cooling structure 81A and a case cooling structure 82. The first engine cooling structure 81A is a means for cooling a cylinder block 35 by leading cooling air led into a case 17 by a cooling fan 85 to the cylinder block 35 of the engine 21, and discharging cooling air used for cooling the cylinder block 35 in a meandering manner. The case cooling structure 82 is a means for cooling the case 17 by leading cooling air led into the case 17 by the cooling fan 85 along the case 17. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an engine-driven generator in which a generator driven by an engine is housed in a case together with the engine.

The engine-driven generator includes an engine that drives the generator, a cooling fan that is coaxially coupled to the drive shaft of the engine, the engine and the cooling fan are accommodated in the case, and an outside air inlet is provided in the case In addition, a small generator provided with a cooling air outlet is known (see, for example, Patent Document 1).
Japanese Patent Application Laid-Open No. 11-2000861

According to the engine-driven generator, by driving the cooling fan, it is possible to guide the outside air from the outside air introduction port into the case, guide the outside air to the engine as cooling air, and cool the engine with the guided cooling air It is said that.
Then, the cooling air that has cooled the engine is guided to the cooling air outlet and is discharged out of the case from the cooling air outlet.

Here, as the engine displacement increases, the engine drive generator increases the engine intake noise and exhaust noise.
For this reason, in a generator equipped with an engine with a large displacement, it is necessary to provide a sound absorbing material on the inner surface of the case to suppress engine intake noise and exhaust sound with the sound absorbing material.

However, providing a sound absorbing material on the inner surface of the case increases the number of parts and hinders weight reduction.
Furthermore, securing a space for attaching the sound absorbing material to the inner surface of the case prevents the engine-driven generator from being compacted.
Thus, it is conceivable that the portability of the engine-driven generator is impaired because the weight of the engine-driven generator increases and it becomes difficult to reduce the size.

In addition, according to the engine drive generator of Patent Document 1, the outside air guided into the case is guided to the engine as cooling air to cool the engine.
For this reason, it has been difficult to reduce the temperature of the case by smoothly flowing cooling air along the inner surface of the case.

  An object of the present invention is to provide an engine-driven generator capable of suppressing engine intake noise and exhaust noise and lowering the temperature of a case without impairing portability.

  The invention according to claim 1 includes an engine for driving a generator, a cooling fan coupled to a drive shaft of the engine, an under cover for supporting the engine, and the engine provided above the under cover. And an engine-driven generator including a case for housing the cooling fan, wherein the cooling air guided into the case by the cooling fan is guided to the cylinder block of the engine to cool the cylinder block, and the cylinder block is A first cooling structure that causes the cooled cooling air to meander and discharge; and a second cooling structure that guides the cooling air guided into the case by the cooling fan along the case and cools the case. It is characterized by having.

  In Claim 2, the case has left and right side wall portions provided at a predetermined interval, a front wall portion is provided at a front end portion of the left and right side wall portions, and a rear wall portion is provided at a rear end portion of the left and right side wall portions. The left and right side wall portions and the front and rear wall portions are formed in a substantially rectangular shape, the cooling fan is provided to face one of the left and right side wall portions, and the first cooling structure is The cooling air is introduced into the case from a first introduction port provided in one of the wall portions, the cylinder block is cooled with the introduced cooling air, and the cooling air that has cooled the cylinder block is sent to the front and rear wall portions. The second cooling structure introduces the cooling air along the case from a second introduction port provided in the under cover. And the cooling air guided along the case Characterized in that the serial outlet configured to exhaust to the outside of the case.

  The first cooling structure includes an engine shroud above the cylinder block to form a cylinder cooling flow path that guides the cooling air to the cylinder block, and the second cooling structure includes: A case cooling flow path that guides the cooling air along the case is formed by providing a case shroud at a predetermined interval with respect to the case.

In the invention which concerns on Claim 1, the 1st cooling structure which cools a cylinder block was provided. In the first cooling structure, the cooling air that has cooled the cylinder block is meandered and discharged.
In this way, by causing the cooling air to meander and discharge, the intake noise of the engine and the exhaust sound of the exhaust gas can hardly be leaked from the outlet of the case together with the cooling air.

Therefore, for example, the intake sound and the exhaust sound can be reduced without attaching a sound absorbing material to the inner surface of the case.
Since it is not necessary to attach a sound absorbing material to the inner surface of the case, it is not necessary to secure a space for attaching the sound absorbing material, and the engine-driven generator can be reduced in size.
Thereby, it is possible to suppress engine intake noise and exhaust gas exhaust noise without impairing portability.

In addition, the invention according to claim 1 includes the second cooling structure that guides the cooling air guided into the case along the case.
Therefore, it is possible to smoothly flow the cooling air along the case.
Thereby, it is possible to reliably suppress the heat of the engine from staying in the vicinity of the inner surface of the case, and to reduce the temperature of the case.

In the invention which concerns on Claim 2, the cooling fan was provided facing one side wall part. Moreover, the 1st inlet of the 1st cooling structure was provided in one of the front and back wall parts.
That is, the 1st inlet was provided in the side part side of a cooling fan. And the outlet for cooling air was provided on the other of the front and rear wall portions.

The cooling air sucked from the first inlet is meandered and guided toward the front of the cooling fan. The cooling air guided in a meandering direction is guided to the engine and cools the engine.
The cooling air that has cooled the engine is guided toward the outlet at the other side wall. Therefore, the cooling air that has cooled the cylinder block can be meandered and discharged.
In this way, by causing the cooling air to meander and exhaust, it is possible to make it difficult for the engine intake sound and exhaust sound to leak from the case outlet along with the cooling air, and to reduce the intake sound and exhaust sound.

In addition, in the invention according to claim 2, the second introduction port of the second cooling structure is formed so as to be able to introduce the cooling air along the case.
Accordingly, the cooling air can be smoothly flowed along the case, and the heat of the engine can be prevented from staying in the vicinity of the inner surface of the case, and the temperature of the case can be lowered.

In the invention according to claim 3, the engine cooling shroud is provided above the cylinder block to form the cylinder cooling flow path.
Accordingly, the cooling air can be reliably guided to the cylinder block through the cylinder cooling flow path, and the cylinder block can be efficiently cooled.

In addition, in the invention according to claim 3, the case cooling flow path is formed by providing the case shroud of the second cooling structure at a predetermined interval with respect to the case.
Accordingly, the cooling air can be reliably guided along the case in the case cooling flow path, and the cooling air can be smoothly flowed along the case to reduce the temperature of the case.

  The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. In the engine-driven generator 10 according to the present invention, the direction to be pulled by the traction handle 125 is the front, and in the figure, the front side is Fr, the rear side is Rr, the left side is L, and the right side is R.

FIG. 1 is a perspective view showing an engine-driven generator according to the present invention, and FIG. 2 is a cross-sectional view showing the engine-driven generator according to the present invention.
The engine-driven generator 10 includes a skeleton member 11 that forms a skeleton as a main body, an engine / generator unit 12 provided on the skeleton member 11, an electrical component 13 that controls the output of the engine / generator unit 12, Intake / fuel supply mechanism 14 for supplying fuel to the engine / generator unit 12 (see FIG. 3), a cooling structure 15 for guiding cooling air to the engine / generator unit 12, and transportation for carrying the engine-driven generator 10 A structure 16, a case 17 that covers the engine / generator unit 12 and the electrical component 13, a heat insulating member 18 that partitions the accommodation space 20 in the case 17, and a muffler 23 ( 4).

The engine-driven generator 10 includes left and right legs 29 at the front end 25a and left and right wheels 31 and 32 at the rear end 25b of the under cover 25 of the skeleton member 11.
The left and right leg portions 29 are each formed of rubber material.
The under cover 25 can be arranged substantially horizontally in a state where the left and right leg portions 29 and the left and right wheels 31 and 32 are grounded.

In the engine-driven generator 10, the engine / generator unit 12 is attached to the under cover 25 of the skeleton member 11 with four attachment members (mount members) 33.
The engine / generator unit 12 is integrally provided with an engine 21 and a generator 22 (see FIG. 4) driven by the engine 21.

The generator 22 is provided coaxially with the drive shaft (crankshaft) 34 of the engine 21 (see FIG. 5).
The engine 21 is arranged in a state in which the cylinder block 35 is inclined at an angle θ about the drive shaft 34 toward the left and right wheels 31 and 32 (specifically, the axle 113 side that supports the left and right wheels 31 and 32). ing.
2 indicates the cylinder center of the cylinder block 35.

By tilting the cylinder block 35 of the engine 21 by the angle θ, the height H1 of the engine 21 can be kept low.
By keeping the height H1 of the engine 21 low, the height of the engine-driven generator 10 can be kept low, and the engine-driven generator 10 can be made compact.

In a state where the cylinder block 35 of the engine 21 is inclined at the angle θ, the wheel housing space 38 can be secured below the cylinder block 35.
The left and right wheels 31 and 32 of the transport structure 16 are disposed in the wheel housing space 38.
By arranging the left and right wheels 31, 32 using the wheel housing space 38, the engine-driven generator 10 can be made more compact.

  3 is a perspective view showing a state where the case is removed from the engine-driven generator shown in FIG. 1, and FIG.

The skeleton member 11 includes an under cover 25 formed to support the engine / generator unit 12, a vertical frame 26 erected in the vicinity of the front end portion 25 a of the under cover 25, an upper center 26 a of the vertical frame 26, and an under The center frame 27 spans the center 25e of the rear end of the cover 25.
The engine / generator unit 12 integrally provided with the engine 21 and the generator 22 is attached to the under cover 25 of the skeleton member 11 with four attachment members 33.

The intake / fuel supply mechanism 14 supplies fuel (air mixture) to the engine 21 of the engine / generator unit 12.
The intake / fuel supply mechanism 14 includes a fuel tank 41 disposed above the generator 22 (see FIG. 5) and a carburetor 101 provided in a cylinder block 35 of the engine 21.

The transport structure 16 includes left and right wheels 31 and 32, a rear fixed handle 118, a front fixed handle 119 (see FIGS. 1 and 2), and a traction handle 125.
As shown in FIG. 2, the front fixed handle 119 is provided so as to cover the support shaft 131 of the traction handle 125.

  According to the transport structure 16, it is possible to swing the traction handle 125 upward about the support shaft 131 to the traction position (the state shown in the figure), and to grip and grip the grip 132 of the traction handle 125. .

That is, by grasping and lifting the grip 132, the left and right leg portions 29 are lifted from the ground (road surface).
By pulling the grip 132 in this state, the left and right wheels 31 and 32 can be rotated to carry (carry) the engine-driven generator 10.

On the other hand, the traction handle 125 is swung downward about the support shaft 131 to fix the traction handle 125 to the front case portion 46 (see FIG. 1).
In this state, it is possible to lift and carry the engine-driven generator 10 by holding the rear fixed handle 118 and the front fixed handle 119.

FIG. 5 is a sectional view taken along line 5-5 of FIG. 1, and FIG. 6 is an exploded perspective view showing a state in which the case is disassembled from the engine-driven generator according to the present invention.
The engine / generator unit 12 is attached (supported) to the under cover 25 in a state in which the drive shaft 34 of the engine 21 is disposed horizontally in the left-right direction. A cooling fan 85 is connected to the drive shaft 34.
Specifically, in the engine 21 of the engine / generator unit 12, the bottom portion 56a of the crankcase 56 is supported by the under cover 25 via mounting members 33 (see FIG. 2).

In the engine / generator unit 12, the drive shaft 34 rotates when the engine 21 is driven. The rotation of the drive shaft 34 is transmitted to the cooling fan 85, and the cooling fan 85 rotates.
As the cooling fan 85 rotates, the rotor 22a of the generator 22 rotates along the outer periphery of the stator 22b. Electric power is generated by the rotation of the rotor 22a.

A center frame 27 of the skeleton member 11 is disposed above the engine / generator unit 12. A heat insulating member 18 is provided on the center frame 27.
The heat insulating member 18 is a member that partitions the unit accommodation area 51 into a hot area 54 on the side where the engine 21 is arranged and a cool area 53 on the side where the generator 22 is arranged.
In the engine / generator unit 12, an elastic sealing material 215 (see also FIGS. 2 and 7) is provided on the entire periphery of the boundary portion 24 between the engine 21 and the generator 22.
The elastic sealing material 215 is a member that partitions the hot region 54 and the cool region 53.

A muffler 23 is provided above the engine 21 of the engine / generator unit 12.
The muffler 23 discharges the exhaust gas discharged from the cylinder block 35 (see FIG. 2) of the engine 21 from the exhaust port 39 (see also FIG. 1).
A fuel tank 41 of the intake / fuel supply mechanism 14 is provided above the generator 22 of the engine / generator unit 12.
Furthermore, an electrical component 13 is provided in front of the engine / generator unit 12.

The engine / generator unit 12, the muffler 23, the fuel tank 41, and the electrical component 13 are accommodated in a case 17 that is formed in a substantially U-shaped cross section.
The electrical unit 13 controls the output of the engine / generator unit 12 and includes an operation panel 79 in the upper half and an inverter unit 78 in the lower half.
The operation panel 79 is provided with an engine start switch, an AC terminal and a DC terminal for outputting generated electric power, and the like so as to face the outside from the opening 48 of the front case portion 46.
The inverter unit 78 is a device that controls the output frequency of the generator 22.

The case 17 is made of a resin such as polypropylene (PP), and includes a case main body 45, a front case portion 46, and a rear case portion 47.
By providing the case 17 above the under cover 25, the housing space 20 is formed by the case 17 and the under cover 25.

The accommodation space 20 is divided into a unit accommodation area 51 and an electrical component accommodation area 52 (see FIG. 2), and the unit accommodation area 51 is divided into a cool area 53 and a hot area 54.
The engine / generator unit 12 is housed in the unit housing area 51, and the electrical equipment section 13 is housed in the electrical equipment housing area 52.
Further, the engine 21 and the muffler 23 are accommodated in the hot area 54, and the generator 22 and the fuel tank 41 are accommodated in the cool area 53.

The case main body 45 is a member that covers the left and right side portions and the upper portion of the unit housing area 51. The engine / generator unit 12 is accommodated in the unit accommodation area 51.
The case body 45 includes a left side case portion 61 that covers the hot area 54, a decorative left cover 62 that is provided below the left side case section 61, a right side case section 63 that covers the cool area 53, A decorative right cover 64 provided at the lower portion of the side case portion 63 is provided.
In the cool region 53, the recoil starter 111, the cooling fan 85, the generator 22, and the fuel tank 41 are arranged.
The engine 21 and the muffler 23 are arranged in the hot region 54.

The left side case portion 61 has a lower end portion 61a attached to the left side portion 25c of the under cover 25, and an upper end portion 61b attached to the upper portion 27a of the skeleton member 11 (center frame 27).
The left side case portion 61 is formed of a left side wall portion (the other of the left and right side wall portions) 66 and an upper left wall portion 67 in a substantially L-shaped cross section.

The right side case portion 63 has a lower end portion 63a attached to the right side portion 25d of the under cover 25, and an upper end portion 63b attached to the upper portion 27a of the skeleton member 11 (center frame 27).
The right side case portion 63 is formed of a right side wall portion (one of the left and right side wall portions) 68 and an upper right wall portion 69 in a substantially L-shaped cross section.
The upper left wall portion 67 of the left side case portion 61 and the upper right wall portion 69 of the right side case portion 63 constitute the upper wall portion of the case 17.

The front case portion 46 is formed in a substantially rectangular lid shape, and is a member that is attached to the under cover 25 or the vertical frame 26 of the skeleton member 11 and constitutes the front wall portion (one of the front and rear wall portions) of the case 17. is there.
The front case portion 46 covers the front portion of the electrical equipment housing area 52 (see FIG. 2).
The electrical part 13 is accommodated in the electrical part accommodating area 52.

The rear case portion 47 is formed in a substantially rectangular lid shape, and is attached to the under cover 25, the center frame 27, etc. of the skeleton member 11 and constitutes the rear wall portion (the other of the front and rear wall portions) of the case 17. It is.
The rear portion of the unit housing area 51 is covered with the rear case portion 47.
The rear case portion 47 is provided with a left cover portion 74 in the left half portion and a right cover portion 75 in the right half portion.

  In this case 17, left and right side wall portions 66 and 68 are provided at a predetermined interval, a front case portion (front wall portion) 46 is provided at the front end portion of the left and right side wall portions 66 and 68, and the left and right side wall portions 66. , 68 is provided with a rear case portion (rear wall portion) 47, and the left and right side wall portions 66, 68 and the front and rear wall portions 46, 47 are formed in a substantially rectangular shape.

A cooling fan 85 is disposed to face the right side wall 68.
Specifically, with the recoil starter 111 interposed between the right side wall 68 and the cooling fan 85, the cooling fan 85 is arranged to face the right side wall 68.
On the other hand, the lid portion 57 of the engine 21 is arranged to face the left side wall portion 66.

  The cooling structure 15 includes an inverter cooling unit 78 for cooling the electric unit 13, the engine 21 and the muffler 23, and a case cooling structure (second cooling structure) 82 for cooling the case 17.

  The engine cooling structure 81 includes a first engine cooling structure (first cooling structure) 81A that cools the upper part of the engine 21 and the muffler 23, and a second engine cooling structure 81B that cools the lower part of the engine 21 and the muffler 23. Yes.

The first engine cooling structure 81 </ b> A includes an introduction louver part (first introduction port) 84 for introducing outside air provided in the lower half part of the front case part 46, and outside air (cooling air) guided from the introduction louver part 84. A first cooling passage 86 that guides the cooling fan 85 through the inverter unit 78 and a second cooling passage (cylinder cooling passage) 87 that guides the cooling air guided to the cooling fan 85 to the cylinder block 35 of the engine 21. (See also FIG. 2), a third cooling channel 88 that guides the cooling air that has passed through the cylinder block 35 to the outlet louver part (outlet port) 89, and the cooling air that is guided to the third cooling channel 88 into the case 17 And a derivation louver unit 89 that discharges to the outside.
In addition, the 1st cooling flow path 86, the 2nd cooling flow path 87, and the 3rd cooling flow path 88 are shown with the white arrow for convenience.

The lead-out louver part 89 is provided in the upper half part (upper part of the case 17) 74a of the left cover part 74.
The second cooling flow path 87 is formed by providing an engine shroud 98 above the cylinder block 35, and is a flow path that guides cooling air to the cylinder block 35.

Here, the cooling fan 85 is provided to face the right side wall portion 68, and the introduction louver portion 84 of the first engine cooling structure 81 </ b> A is provided in the front case portion 46.
That is, the introduction louver portion 84 is provided on the side of the cooling fan 85. A cooling air derivation louver portion 89 is provided in the rear case portion 47.

The cooling air sucked from the introduction louver 84 is meandered and guided by the first cooling flow path 86 toward the front surface 85 a of the cooling fan 85. The cooling air that is meandered and guided is led to the engine 21 to cool the engine 21.
The cooling air that has cooled the engine 21 is guided toward the left side wall 66 (specifically, the case shroud 97) by the second cooling flow path 87, and is led out by the left side wall 66 (specifically, the case shroud 97). Guided toward the louver unit 89.

Therefore, the cooling air that has cooled the engine 21 meanders, is guided to the derivation louver unit 89, and is discharged from the derivation louver unit 89.
In this way, by causing the cooling air to meander and discharge, the intake sound and exhaust sound of the engine 21 can be made difficult to leak from the derivation louver unit 89 together with the cooling air, and intake sound and exhaust sound can be reduced.
The case shroud 97 is provided at a predetermined interval with respect to the left side case portion 61.

According to the first engine cooling structure 81A, outside air (cooling air) is introduced into the case 17 from the introduction louver 84, and the introduced cooling air is supplied to the inverter unit 78, the upper part of the engine 21 (mainly the cylinder block 35), and It is possible to guide to the muffler 23.
Therefore, the inverter unit 78, the upper part of the engine 21 (mainly the cylinder block 35), and the muffler 23 can be cooled with the cooling air.
And the cooling air which cooled the inverter unit 78, the engine 21 (cylinder block 35), and the muffler 23 can be discharged | emitted from the derivation louver part 89 to the exterior of the case 17. FIG.
The first engine cooling structure 81A will be described in more detail with reference to FIG.

The second engine cooling structure 81B is led from the seventh cooling flow path 134 and the seventh cooling flow path 134 branched from the first cooling flow path 86 of the first engine cooling structure 81A and guided to the lower side of the generator side 22. Along the 8th cooling flow path 135 for guiding the cooled cooling air to the heat radiating fin 58, the heat radiating fin 58 for guiding the cooling air guided from the 8th cooling flow path 135 to the upper part of the crankcase 56, and the heat radiating fin 58 A lead-out louver portion 89 that discharges the cooling air rising to the top of the crankcase 56 to the outside of the case 17 is provided.
For convenience, the seventh cooling channel 134 and the eighth cooling channel 135 are indicated by white arrows.

The derivation louver portion 89 is a member shared with the first engine cooling structure 81A.
The seventh cooling flow path 134 is a flow path that branches outside air (cooling air) from the first cooling flow path 86 of the first engine cooling structure 81 </ b> A and guides it below the generator 22 through the cooling fan 85.
The eighth cooling channel 135 is formed by the under cover 25 and the bottom portion 56 a of the crankcase 56 and is a channel for guiding the cooling air to the heat radiating fins 58.

According to the second engine cooling structure 81B, the outside air (cooling air) introduced into the case 17 from the introduction louver portion 84 is branched to the seventh cooling flow path 134 and guided below the generator 22, It is possible to cool the lower part.
The cooling air guided to the lower side of the generator 22 is guided to the bottom portion 56a of the crankcase 56 by the eighth cooling flow path 135, and the bottom portion 56a of the crankcase 56 can be cooled.

The cooling air guided to the radiating fins 58 in the eighth cooling channel 135 can be guided upward along the radiating fins 58 as indicated by arrows to cool the radiating fins 58.
The cooling air that has cooled the radiating fins 58 can be discharged from the lead-out louver portion 89 to the outside of the case 17.
The second engine cooling structure 81B will be described in more detail with reference to FIG.

The case cooling structure 82 includes an introduction slit portion (second introduction port) 91 for introducing outside air provided in the left side portion 25 c of the under cover 25 and the outside air guided from the introduction slit portion 91 along the left side case portion 61. Accordingly, a fourth cooling channel (case cooling channel) 92 that guides to the upper side of the muffler 23, a guide port 93 (see also FIG. 2) formed in the center frame 27, and the outside air of the fourth cooling channel 92 And a fifth cooling channel (case cooling channel) 94 that guides the fuel tank 41 upward through the guide port 93... And the outside air guided to the upper side of the fuel tank 41 is cooled along the right side case part 63. And a sixth cooling channel (case cooling channel) 95 that guides the fan 85.
In addition, the 4th cooling flow path 92, the 5th cooling flow path 94, and the 6th cooling flow path 95 are shown with the white arrow for convenience.

Here, the case cooling structure 82 has the introduction slit portion 91 formed along the left side case portion 61 so that the cooling air can be introduced.
The introduction slit portion 91 is a slit formed in the left side portion 25c of the under cover 25 so as to face in the front-rear direction and to have a certain length. A plurality of introduction slit portions 91 are formed at predetermined intervals along the left side portion 25c.
As a result, the cooling air can flow smoothly along the left side case portion 61, and the heat of the engine 21 can be prevented from staying in the vicinity of the inner surface of the case 17, thereby reducing the temperature of the case 17.

Further, the fourth cooling flow path 92 is a flow path formed between the left side case portion 61 and the case shroud 97 by including the case shroud 97 at a predetermined interval with respect to the left side case portion 61. is there.
Therefore, the cooling air can be reliably guided along the inner surface of the left side case portion 61 in the fourth cooling flow path 92.
As a result, the cooling air can flow smoothly along the left side case portion 61 and the temperature of the case 17 can be lowered.

According to the case cooling structure 82, outside air (cooling air) is introduced from the introduction slit portion 91, and the introduced cooling air is smoothly guided along the inner surface of the left side case portion 61 and the inner surface of the right side case portion 63. It is possible.
By smoothly guiding outside air along the inner surface of the left side case portion 61 and the inner surface of the right side case portion 63, the left and right side case portions 61 and 63 can be cooled.

7 is a perspective view showing a state in which the engine / generator unit according to the present invention is attached to the under cover, and FIG. 8 is an exploded perspective view showing a state in which the engine / generator unit in FIG. 7 is disassembled from the under cover.
An engine shroud 98 is attached to the upper part of the crankcase 56 and the upper part of the cylinder block 35 with bolts 99 at a predetermined interval.
A front half space 87a is formed by the upper portion of the crankcase 56 and the front half portion 98a of the engine shroud 98, and a rear half space 87b is formed by the upper portion 35a of the cylinder block 35 and the rear half portion 98b of the engine shroud 98. .

The first cooling space 87 of the first engine cooling structure 81A is formed in the front half space 87a and the rear half space 87b.
Accordingly, the cooling air can be reliably guided to the cylinder block 35 through the second cooling flow path 87, and the cylinder block 35 can be efficiently cooled.

  As described above, the first engine cooling structure 81A includes the introduction louver portion 84 (see FIG. 6) for introducing outside air, the curved first cooling flow path 86, the second cooling flow path 87, and the third cooling. The flow path 88 and the derivation louver part 89 (refer FIG. 6) are provided.

Next, the second engine cooling structure 81B will be described.
The engine / generator unit 12 is attached to the under cover 25 with attachment members 33 (see FIG. 2).
By attaching a lid 57 to the left side of the crankcase 56 of the engine 21, the opening of the crankcase 56 is closed by the lid 57.
The lid body 57 is provided with heat radiating fins 58 on the side wall portion 57a in the vertical direction.
The side wall portion 57 a is a portion constituting the wall portion on the opposite side of the cooling fan 85 in the crankcase 56.

  When the engine / generator unit 12 is attached to the under cover 25 with attachment members 33 (see FIG. 2), the bottom portion 56a of the crankcase 56 of the engine 21 is connected to the guide portion 221 of the under cover 25 as shown in FIG. Are arranged along.

Specifically, the bottom portion 56 a of the crankcase 56 is disposed above the guide portion 221 with a predetermined interval.
The guide part 221 includes an inclined part 221a formed near the center of the under cover 25, a horizontal part 221b formed outside the inclined part 221a, a mounting groove 223 formed along the outer edge of the guide part 221, And a convex guide portion 225 provided in the mounting groove 223.

The inclined portion 221a is a portion that is inclined with an upward gradient from the vicinity of the center portion of the under cover 25 toward the outside.
The horizontal portion 221b is a portion that is provided at the upper end of the inclined portion 221a and is formed substantially parallel to the bottom portion 56a of the crankcase 56.
The horizontal part 221b is formed below the bottom part 56a of the crankcase 56 at a predetermined interval.

The mounting groove 223 is formed along the outer periphery of the bottom portion 56a of the crankcase 56 disposed above. A convex guide portion 225 is attached to the attachment groove 223.
The convex guide portion 225 includes a front ridge piece 225a erected along the front outer periphery of the bottom portion 56a, a central ridge piece 225b erected along the left outer periphery of the bottom portion 56a, and a rear outer periphery of the bottom portion 56a. And a rear ridge piece 225c erected along.
The central ridge piece 225b is disposed with an interval S (see FIG. 5) with respect to the left outer periphery 56c of the bottom portion 56a.

A space 227 is formed by the bottom portion 56 a of the crankcase 56 and the guide portion 221 of the under cover 25.
The space 227 is closed at the front part by the front protrusion piece 225a and at the rear part by the rear protrusion piece 225c.
Further, a central protrusion 225 b is disposed on the left side of the space 227.
An eighth cooling channel 135 of the second engine cooling structure 81B is formed by the bottom portion 56a of the crankcase 56, the guide portion 221 of the under cover 25, and the convex guide portion 225.

  As described above, the second engine cooling structure 81B includes the seventh cooling flow path 134 branched from the first cooling flow path 86 of the first engine cooling structure 81A, the eighth cooling flow path 135, the radiating fins 58, and the like. And a derivation louver unit 89.

According to the eighth cooling flow path 135 of the second engine cooling structure 81B, the cooling air guided to the lower side of the generator 22 is efficiently guided to the heat radiating fins 58 by the front protrusion pieces 225a and the rear protrusion pieces 225c. It is possible to cool the bottom portion 56a of the case 56.
Furthermore, according to the eighth cooling flow path 135, the guided cooling air can be raised upwards with the central protrusion piece 225b.

A heat radiating fin 58 is provided above the central ridge piece 225b. The heat radiating fins 58 are provided in the vertical direction.
Therefore, the cooling air raised by the central ridge piece 225b can be favorably guided along the radiating fin 58 as indicated by an arrow.
That is, the eighth cooling flow path 135 includes the convex guide portion 225, so that it is possible to guide the cooling air along the crankcase 56 to the heat radiating fins 58.

Next, returning to FIG. 6, an example in which the inverter unit 78, the engine 21, the muffler 23, and the like are cooled by the first engine cooling structure 81A will be described.
By operating the cooling fan 85 (see FIG. 5), outside air (cooling air) is introduced into the case 17 from the introduction louver portion 84. The introduced cooling air is guided to the cooling fan 85 through the first cooling flow path 86 in a curved shape.

The inverter unit 78 is cooled by the cooling air flowing through the first cooling flow path 86.
The cooling air blown out from the cooling fan 85 is guided to the second cooling flow path 87.
The upper part 56b of the crankcase 56 and the upper part 35a of the cylinder block 35 (see FIG. 8) are cooled by the cooling air guided to the second cooling flow path 87.

The cooling air that has cooled the upper portion 56b of the crankcase 56 and the upper portion 35a of the cylinder block 35 is guided by the left side wall portion 66 (specifically, the inner surface of the shroud 97 for cases) and guided toward the muffler 23 in a curved shape.
The muffler 23 is cooled by the cooling air flowing through the second cooling flow path 87.
The cooling air that has cooled the muffler 23 is guided to the third cooling flow path 88. The cooling air guided to the third cooling flow path 88 is discharged to the outside of the case 17 through the outlet louver part 89.

As described above, the cooling air introduced from the introduction louver portion 84 into the case 17 is guided in a curved shape by the first cooling flow path 86 and further guided by the third cooling flow path 88 in a curved shape.
Therefore, the cooling air that has cooled the upper part 56 b of the crankcase 56 and the upper part 35 a of the cylinder block 35 can be caused to meander and discharged from the outlet louver part 89.

In this manner, the cooling air is meandered and discharged through the first and second cooling flow paths 86 and 88, so that the intake sound of the engine 21 and the exhaust sound of the exhaust gas together with the cooling air are extracted from the louver portion 89 of the case 17. It is difficult to leak from.
Thereby, for example, an intake sound and an exhaust sound can be reduced without attaching a sound absorbing material to the inner surface of the case 17.

Since it is not necessary to attach a sound absorbing material to the inner surface of the case 17, it is not necessary to secure a space for attaching the sound absorbing material, and the engine-driven generator 10 can be reduced in size.
Thereby, it is possible to suppress engine intake noise and exhaust gas exhaust noise without impairing portability.

Next, referring back to FIGS. 6 and 8, an example in which the second engine cooling structure 81B cools the bottom portion 56a of the crankcase 56, the lid 57 of the crankcase 56, and the like will be described.
By operating the cooling fan 85 (see FIG. 5), the outside air (cooling air) introduced from the introduction louver portion 84 into the case 17 is branched into the seventh cooling flow path 134.
The cooling air branched into the seventh cooling channel 134 is guided below the generator 22.

The lower part of the generator 22 is cooled by the cooling air flowing through the seventh cooling channel 134.
The cooling air that has cooled the lower part of the generator 22 is guided to the eighth cooling channel 135 and flows along the bottom 56 a of the crankcase 56.
The bottom 56a of the crankcase 56 is cooled by the cooling air flowing through the eighth cooling channel 135.

The cooling air that has passed through the bottom portion 56 a of the crankcase 56 is guided upward by the central protrusion 225 b of the convex guide portion 225.
The cooling air guided upward rises along the radiation fins 58.
The lid 57 (radiation fin 58) of the crankcase 56 is cooled by the cooling air flowing along the radiation fin 58.
The cooling air that has cooled the lid 57 (radiating fins 58) is discharged from the lead-out louver portion 89 to the outside of the case 17.

As described above, the eighth cooling channel 135 is formed by the guide portion 221 of the under cover 25 and the bottom portion 56 a of the crankcase 56, and the cooling air is guided to the radiating fins 58 by the eighth cooling channel 135.
Here, the eighth cooling flow path 135 includes the convex guide portion 225, so that the cooling air can be guided better along the crankcase 56.
Therefore, the bottom portion 56a of the crankcase 56 can be more efficiently cooled by the cooling air guided to the eighth cooling channel 135.

Further, the heat radiating fins 58 are provided on the side wall portions 57a of the lid body 57 in the vertical direction.
Therefore, the cooling air guided to the heat radiation fins 58 in the eighth cooling flow path 135 is smoothly guided upward along the heat radiation fins 58.

Here, the eighth cooling flow path 135 includes the convex guide portion 225 (specifically, the central ridge piece 225b), so that the cooling air can be favorably raised upward at the central ridge piece 225b. it can.
Therefore, it is possible to guide the cooling air along the heat radiating fins 58 and cool the side wall 57a of the lid 57 more efficiently.

Further, a lead-out louver portion 89 (see FIG. 6) is provided in the upper half portion of the left cover portion 74.
Therefore, the cooling air that has risen along the radiation fins 58 can be discharged well from the lead-out louver portion 89 to the outside of the case 17.

  In this way, the bottom portion 56a of the crankcase 56 is efficiently cooled by the cooling air guided to the eighth cooling flow path 135, and the lid 57 of the crankcase 56 is efficiently cooled by the cooling air guided to the radiation fin 58. By doing so, the cooling efficiency of the engine 21 can be improved.

  In addition, by forming the eighth cooling channel 135 at the guide portion 221 of the under cover 25 and the bottom portion 56a of the crankcase 56, the under cover 25 is also used as a member that forms part of the eighth cooling channel 135. be able to.

Therefore, the large shroud shown in the prior art can be removed, and a space for installing the large shroud can be eliminated.
As a result, the engine-driven generator 10 can be reduced in weight, and the engine-driven generator 10 can be reduced in size, and the portability of the engine-driven generator 10 can be ensured satisfactorily.

Next, returning to FIG. 5, an example in which the case 17 is cooled by the case cooling structure 82 will be described.
By operating the cooling fan 85, outside air (cooling air) is introduced into the case 17 from the introduction slit portion 91.
The cooling air introduced into the case 17 is guided to the fourth cooling flow path 92 and smoothly flows along the inner surface of the left side case portion 61.
The left side case portion 61 is cooled by the cooling air flowing through the fourth cooling flow path 92.

The cooling air that has cooled the left side case portion 61 is guided to the fifth cooling flow path 94 and smoothly flows along the inner surface of the right side case portion 63.
The right side case portion 63 is cooled by the cooling air flowing through the fifth cooling flow path 94.
The cooling air that has cooled the right side case portion 63 is guided to the sixth cooling flow path 95 and flows into the cooling fan 85.

Thus, the outside air (cooling air) introduced from the introduction slit portion 91 can be smoothly flowed along the inner surfaces of the left and right side case portions 61 and 63.
Thereby, it is possible to reliably suppress heat of the engine 21 from staying in the vicinity of the inner surfaces of the left and right side case portions 61 and 63 and to reduce the temperature of the case 17.

Here, of the cooling air that has been cooled to the left side case portion 61 and led to the fifth cooling flow path 94, some of the cooling air flows into the cooling flow path 96 between the fuel tank 41 and the heat insulating member 18. Flowing.
The cooling air that has flowed through the cooling flow path 96 joins the sixth cooling flow path 95 and flows into the cooling fan 85.
As described above, the cooling efficiency of the cool region 53 can be further improved by causing some cooling air to flow through the cooling flow path 96.

  Note that the case 17, the under cover 25, the front case portion 46, the rear case portion 47, the lead-out louver portion 89, the introduction slit portion 91, the case shroud 97, the engine shroud 98, and the like illustrated in the above-described embodiment are illustrated. It is not limited to this, and can be changed as appropriate.

  The present invention is suitable for application to an engine-driven generator in which a generator driven by an engine is housed inside a case together with the engine.

It is a perspective view which shows the engine drive generator which concerns on this invention. It is sectional drawing which shows the engine drive generator which concerns on this invention. It is a perspective view which shows the state which removed the case from the engine drive generator of FIG. It is a disassembled perspective view which shows the engine drive generator of FIG. FIG. 5 is a sectional view taken along line 5-5 of FIG. It is a disassembled perspective view which shows the state which decomposed | disassembled the case from the engine drive generator which concerns on this invention. It is a perspective view which shows the state which attached the engine / generator unit which concerns on this invention to the undercover. It is a disassembled perspective view which shows the state which decomposed | disassembled the engine / generator unit of FIG. 7 from the undercover.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Engine drive generator, 17 ... Case, 21 ... Engine, 22 ... Generator, 25 ... Under cover, 33 ... Cylinder block, 34 ... Drive shaft, 46 ... Front case part (front wall part), 47 ... Rear case Part (rear wall part), 66 ... left side wall part, 68 ... right side wall part, 81A ... first engine cooling structure (first cooling structure), 82 ... case cooling structure (second cooling structure), 84 ... introduction louver part (First inlet), 85 ... cooling fan, 87 ... second cooling channel (cylinder cooling channel), 89 ... outlet louver part (outlet port), 91 ... inlet slit part (second inlet), 92 ... Fourth cooling channel (case cooling channel), 94 ... Fifth cooling channel (case cooling channel), 95 ... Sixth cooling channel (case cooling channel), 97 ... Shroud for case, 98 ... For engine Shroud.

Claims (3)

A case that includes an engine that drives a generator, includes a cooling fan that is coupled to a drive shaft of the engine, includes an under cover that supports the engine, and is provided above the under cover to accommodate the engine and the cooling fan In the engine drive generator with
A first cooling structure that guides the cooling air guided into the case by the cooling fan to the cylinder block of the engine to cool the cylinder block, meandering and discharging the cooling air that has cooled the cylinder block;
A second cooling structure that cools the case by guiding the cooling air introduced into the case by the cooling fan along the case;
An engine-driven generator characterized by comprising: The case is provided with left and right side wall portions at a predetermined interval, a front wall portion is provided at a front end portion of the left and right side wall portions, a rear wall portion is provided at a rear end portion of the left and right side wall portions, It is formed in a substantially rectangular shape with the side wall part and the front and back wall parts,
The cooling fan is provided opposite to one of the left and right side wall portions,
The first cooling structure introduces the cooling air into the case from a first introduction port provided on one of the front and rear wall portions, cools the cylinder block with the introduced cooling air, The cooled cooling air is configured to be discharged out of the case from the outlet provided in the other of the front and rear wall portions,
The second cooling structure introduces the cooling air along the case from a second inlet provided in the under cover, and sends the cooling air guided along the case from the outlet to the case. The engine-driven generator according to claim 1, wherein the engine-driven generator is configured to discharge outside. The first cooling structure is provided with an engine shroud above the cylinder block to form a cylinder cooling flow path that guides the cooling air to the cylinder block;
The said 2nd cooling structure is provided with the shroud for cases at predetermined intervals with respect to the said case, The case cooling flow path which guides the said cooling wind along the said case was formed. The engine-driven generator according to claim 1 or 2.

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