JPH0156253B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention includes an engine housed in a casing,
This invention relates to a small power generation device that has an improved cooling structure with a generator that is directly connected to and driven by the power generation device.

(Prior Art) FIG. 1 is a partially cutaway side view of a conventional small power generator, and FIG. 2 is a partially cutaway plan view. In FIG. 1, reference numeral 1 denotes a box-shaped casing provided with a portable handle 2. Inside this engine 1, an engine 3 and a generator 4 driven by the engine 3 are housed. Elastically supported.

The crankshaft 6 of the engine 3 and the rotating main shaft 7 of the generator 4 are directly connected to each other. The direct coupling portion 8 is supported by a bearing portion 10 of the outer shell 9 of the generator 4, while the opposite end portion 11 of the crankshaft 6 is supported by a bearing portion 13 of the crankcase 12. An end 11 on the opposite side of the crankshaft 6 protrudes outside the crankcase 12, and an engine cooling fan 14 is provided on the protrusion. In addition, the rotating main shaft 7
A generator cooling fan 15 that rotates within the outer shell 9 is attached to the generator. A plurality of intake holes 16 are provided on the end wall of the outer shell 9 of the generator 4 on the side opposite to the engine,
On the other hand, a plurality of exhaust holes 17 are provided in a circumferential portion of the outer shell 9 facing the fan.

Furthermore, a recoil starter 20 for driving the opposite end 11 of the crankshaft 6 is attached to a baffle plate 19 that covers the cylinder 18a, cylinder head 18b, and engine cooling fan 14 of the engine 3. The recoil starter 20 includes a plurality of intake holes 21 to the engine cooling fan 14. On the other hand, the outlet 22b of the baffle plate 19 is connected to the generator 4
and the fuel tank 23. A large number of ventilation holes 2 are provided in the side walls 24 and 25 of the casing 1, which face each other with the engine 3 and the generator 4 in between.
6 and 27 are drilled.

In addition, in FIG. 1, 28 is a piston of the engine 3, 29 is a crank gear, 30 is a high pressure cord for ignition, 31 is a muffler, and in FIG. 2, 32 is a carburetor, 33 is an air cleaner, 34 is a starter handle, 39 is a dedicated exhaust hole for the muffler 31.

In the above configuration, when the engine 3 is driven,
The engine cooling fan 14 connects the air intake hole 2 of the recoil starter 20 from the air hole 27 of the casing 1 to the air intake hole 2 of the recoil starter 20.
1, a cooling air 35a passing through the cylinder 18a is generated, and the cooling air 35a passes through the cylinder 8a and the cylinder head 18.
b is cooled. Furthermore, the generator cooling fan 15 generates cooling air 35b that passes through the generator 4 from the ventilation hole 26 on the opposite side of the casing 1, through the intake hole 16 of the generator 4, and cools the generator 4. The latter cooling air 35b exits the generator from the exhaust hole 17, and flows out of the casing 1 from the ventilation holes 26 and 27 together with the former cooling air 35a.

As can be seen from the above description, in the conventional configuration, hot air 38a and 38b as exhaust flows around the intake air 36a to the engine 3 and the intake air 6b to the generator 4 in the opposite direction. ,
The turbulence of the airflow is large, causing considerable noise, and a portion of the hot air 38a, 38b is absorbed into the intake air 3.
6a, 36b, or this intake air 6a,
36b flow in opposite directions to each other, and air stagnation occurs within the casing 1, making it impossible to sufficiently cool the engine 3 and generator 4.

As a solution to these inconveniences, Jikaisho
FIG. 5 shows the power generation device disclosed in Japanese Patent No. 58-59357.

In FIG. 5, first intake holes 55A and 55B for introducing cooling air into the casing 1 are formed on the generator 4 side of the casing 1. On the other hand, an exhaust hole 56 is formed on the engine 3 side of the casing 1 to exhaust the cooling air inside the casing 1.

The cooling fan 5 in the generator 4 passes through the first intake hole 55A and the intake hole 16 of the generator 4,
Cooling air is taken into the generator 4, and this is sent to the generator 4.
It is discharged from the exhaust hole 17. On the other hand, the cooling fan 14 of the engine 4 takes in cooling air into the casing 1 through the first intake hole 55B, cools the cylinder 18a and cylinder head 18b of the engine 3, and further cools the radiator 100.
and the exhaust hole 17 of the generator 4.
Cooling air from the engine 3 is guided to the radiator 100 through the space below the oil pan 18c of the engine 3 to cool the radiator 100. The cooling air that has cooled these radiators 100 is transferred to the casing 1
The air is discharged from the exhaust hole 56.

Thus, this prior art provides a radiator 10
Although this is for a relatively large power generation device having 0, turbulence in the airflow can be reduced by preventing a flow in the opposite direction from occurring in the flow of cooling air. Therefore, efficient cooling can be achieved and the soundproofing effect can be improved. Moreover, the first part of casing 1
Since the cooling air introduced from the intake hole 55B cools the fuel tank 23, it is possible to suppress a rise in fuel temperature.

However, this prior art requires two cooling fans 15 and 14 to cool the fuel tank 23, generator 4, and engine 3. Therefore, it is inevitable that the power generation device becomes large and heavy.

(Object of the Invention) The present invention has been made in view of the above-mentioned conventional disadvantages, and an object of the present invention is to provide a small power generation device that is small and lightweight, and can improve cooling efficiency and soundproofing effects.

(Means for Solving the Problems) In order to achieve the above object, the present invention first provides an engine cylinder and a cylinder head from the generator side to the direct connection between the engine crankshaft and the rotating main shaft of the generator. A cooling fan is installed that generates cooling air flowing to the side. Further, the cooling air introduced into the casing from the first intake hole provided on the generator side of the casing is introduced into the upstream portion of the outer shell of the generator through the second intake hole. The cooling air that has flowed around the outer circumference of the outer shell of the generator from the first intake hole is transferred to the outer shell of the generator via the third intake hole formed downstream of the outer circumference of the outer shell of the generator. Introduced into the downstream part of the The cooling fans introduced into the outer shell of the generator are sucked into the engine cylinders and Flows to the cylinder head side. Further, the casing is provided with a backflow prevention plate that protrudes from the casing inward in the radial direction of the crankshaft to prevent cooling air on the engine side within the casing from flowing back toward the fuel tank and the generator.

(Function) According to the present invention, since the air intake port is provided at the end of the outer shell of the generator that faces the cooling fan, the air is introduced into the casing through the first air intake hole, and further, the air is introduced into the casing through the second and third air intake holes. All the cooling air introduced into the outer shell of the generator from the intake holes of the engine can be sucked into the cooling fan, and since this cooling air is flowed to the cylinders of the engine, it is possible to use one cooling fan. Therefore, the generator and engine can be cooled.

By the way, while there is only one cooling fan,
Since the generator, engine, fuel tank, etc. are located inside the casing, the passage of cooling air is complicated. must be prevented from flowing back into the generator and fuel tank. Here, in this invention, since the backflow prevention plate is provided that protrudes from the casing to the inside in the radial direction of the crankshaft, it is possible to prevent the cooling air on the engine side in the casing from flowing back toward the fuel tank and the generator side. .

(Embodiment) FIG. 3 is a partially cutaway side view of a small power generator according to an embodiment of the present invention, and FIG. 4 is a partially cutaway plan view. In these figures, the same or equivalent parts as in the conventional example shown in FIG. 1 are given the same reference numerals.

In FIG. 3, the crankshaft 6 of the engine 3
and the rotating main shaft 7 of the generator 4 driven by this.
are directly connected to each other. The opposite opening of the crank chamber 60 in the engine 3 is closed by a side cover 40 which is detachably screwed. A cooling fan 50 that cools the engine 3 and the generator 4 is attached to a direct connection portion 8 between the crankshaft 6 and the rotating main shaft 7. Near the direct connection portion 8 is a bearing portion 10 of the crankcase 12.
On the other hand, the opposite end 11 of the crankshaft 6 is supported by a bearing 13 formed inside the side cover 40. A recoil starter 20 for driving the rotating main shaft 7 is attached to the end of the outer shell 9 of the generator 4 on the side opposite to the engine, and the recoil starter 20 has a plurality of second intake holes 21 .

A cooling fan 50 is installed in the outer shell 9 of the generator 4.
An intake port 51 is formed at an end facing the cooling fan 50 , and a fan chamber 53 having an exhaust port 52 is formed at the outer peripheral portion of the cooling fan 50 . A plurality of third intake holes 54 are bored in the cylindrical portion of the outer shell 9 of the generator 4 near the fan. Engine 3, generator 4
is housed in the casing 1, and the portion of the front and rear, left and right side walls (only the left and right side walls are shown in FIG. 3) S of the casing 1 that is close to the recoil starter 20, that is, the end of the generator 4 on the side opposite to the engine. A first intake hole 55 is provided in the portion 24 adjacent to the
However, there are many. On the other hand, a large number of exhaust holes 56 are provided in a portion 25 of the right side wall S of the casing 1 that is close to the end of the engine 3 on the side opposite to the generator. The fuel tank 23 is disposed within the casing 1 in close proximity to the generator 4, and the fuel tank 23
A wind guiding surface 57 consisting of a recessed portion is formed at a portion facing the cooling fan 50 .

Further, the muffler 31 of the engine 3 is disposed on the opposite side from the generator 4, and is covered with the cylinder 18a and cylinder head 18b by a baffle plate 19, which has a cooling air inlet 22a on the side of the cooling fan 50. , an outlet 22b is provided on the muffler 31 side.

In Fig. 3, 58 is a hot air backflow prevention plate;
It protrudes from the casing 1 inward in the radial direction of the crankshaft 6 and is fixed to the casing 1.

Next, the flow of cooling air will be explained.

When the engine 3 is driven, the cooling fan 50 rotates, and cooling air is introduced into the casing 1 from the first intake hole 55 of the casing 1. This cooling air includes a cooling air 59a introduced into the upstream part of the outer shell 9 of the generator 4 through the second intake hole 21 of the recoil starter 20, and a cooling air 59a that passes through the outer periphery of the outer shell 9 of the generator 4. It is divided into wind 59b and the generator 4 is cooled. The latter cooling air 59b is sucked into the downstream part of the outer shell 9 of the generator from the third intake hole 54, merges with the former cooling air 59a, and is introduced into the fan chamber 53 via the intake port 51. , and is further discharged from the fan chamber 53. These cooling air 59a, 5
9b changes its direction by the air guide surface 57 of the fuel tank 23, cools the cylinder 18a and cylinder head 18b of the engine 3, and then moves to the muffler 31.
and flows out of the casing 1 from the exhaust hole 56.

In the above configuration, since the air intake port 51 is provided at the end of the outer shell 9 of the generator 4 facing the cooling fan 50, the air is introduced into the casing 1 through the first air intake hole 55 of the casing 1, and 2 and 3 from the outer shell 9 of the generator 4
All of the cooling air 59a, 59b introduced into the
This cooling air can be drawn into the cooling fan 50, and the cooling air 59a, 59b can be drawn into the cylinder 18a.
Since it flows to the cylinder head 18b, the generator 4 and engine 3 can be cooled by one cooling fan 50.

In addition, by providing the fuel tank 23 close to the generator 4, the power generation device becomes smaller, but in order to prevent the fuel temperature in the fuel tank 23 from rising, it is necessary to provide cooling around the fuel tank. You need to let the wind flow. Here, in this invention, since the third intake hole 54 is formed in the downstream part of the outer periphery of the outer shell 9 of the generator 4, the cooling air 59b also flows around the outer periphery of the outer shell 9 of the generator 4. . Therefore, the fuel tank 23 close to the outer periphery of the generator 4 is cooled by one cooling fan 50.

By the way, since the generator 4, the engine 3, the fuel tank 23, etc. are disposed inside the casing 1, the cooling air passage is complicated. It is necessary to prevent the cooling air that has flowed toward the engine 4 from flowing back toward the generator 4 and fuel tank 23. Here, the present invention provides a backflow prevention plate 5 that protrudes from the casing 1 inward in the radial direction of the crankshaft 6.
8, it is possible to prevent the cooling air from the engine 3 side from flowing back toward the fuel tank 23 and the generator 4 side even at a location radially outward from the cooling fan 50.

In this way, with one cooling fan 50,
Since the generator 4, fuel tank 23, and engine 3 can be cooled by flowing the cooling air in one direction, the cooling efficiency and soundproofing effect are improved, and the power generation device becomes smaller and lighter.

In addition, in the case of the above embodiment, the muffler 31 is placed on the opposite side of the engine 3 from the generator 4 and is cooled by the cooling air that has passed through the engine 3. The range of material selection can be expanded.

In addition, in FIG. 3, the generator 4 includes a flywheel magnet (not shown) for engine ignition.
However, the flywheel magnet may be formed integrally with the cooling fan 50. Furthermore, the crankshaft 6 of the engine 3 and the rotating main shaft 7 of the generator 4 may be connected by a shaft joint that is a separate component. Furthermore, although the recoil starter 20 is housed in the casing 1 in FIG. 3, the recoil starter 20 may be configured to protrude outside the casing 1.

(Effects of the Invention) As explained above, according to the present invention, a single cooling fan can flow cooling air in one direction to cool the generator, fuel tank, and engine, thereby improving cooling efficiency and soundproofing. Not only is the effectiveness improved, but the compact power generator, which should originally be small and lightweight, becomes smaller and lighter.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway side view of a conventional small power generator, FIG. 2 is a partially cutaway plan view, FIG. 3 is a partially cutaway side view of a small power generator according to an embodiment of the present invention, and FIG. The figure is a partially cutaway plan view, and FIG. 5 is a partially cutaway side view of a conventional power generating device. 1... Casing, 3... Engine, 4... Generator,
6...Crankshaft, 7...Rotating main shaft, 8...Direct connection part, 9
...Outer shell, 18a...Cylinder, 18b...Cylinder head, 21...Second intake hole, 23...Fuel tank,
24, 25... Adjacent portion, 50... Cooling fan,
51...Intake port, 54...Third intake hole, 55...First
intake hole, 56...exhaust hole, 59a, 59b...cooling air, S...side wall.

Claims (1)

[Scope of Claims] 1. An engine, a generator directly connected to the engine and driven, and a fuel tank close to the outer periphery of the outer shell of the generator are housed in a casing, and the power generation is carried out on the side wall of the casing. A small power generation device having a first intake hole in a portion close to the opposite end of the engine and an exhaust hole provided in a portion close to the opposite end of the engine to the generator, the crankshaft of the engine A cooling fan that generates cooling air flowing from the generator side to the cylinder and cylinder head side of the engine is attached to a direct connection between the generator and the rotating main shaft of the generator, and
a second intake hole that introduces the cooling air introduced into the casing from the intake hole into the upstream part of the outer shell of the generator; a third intake hole for introducing the cooling air flowing around the outer circumference of the outer shell of the generator from the first intake hole into a downstream part within the outer shell of the generator; and an end of the outer shell of the generator facing the cooling fan. An intake port is formed in the casing to draw cooling air from the outer shell of the generator into the cooling fan, and an intake port protrudes from the casing inward in the radial direction of the crankshaft to direct cooling air from the engine side inside the casing to the fuel tank and the cooling fan. A small power generator equipped with a backflow prevention plate that prevents backflow to the generator side. 2. The small power generator according to claim 1, wherein the muffler is disposed on the opposite side of the engine from the generator.