JPH0139856Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to cooling of a forced air-cooled engine and generator disposed inside a soundproof case, and in particular, a cooling device for an engine-driven generator that has an improved inlet for introducing cooling air into the soundproof case. It is related to.

Conventionally, a forced air-cooled engine and a generator are arranged inside a soundproof case, and cooling air is sucked into the interior through an inlet formed in a part of the soundproof case, and after cooling the engine and generator, the engine and generator are placed in a soundproof case or a base plate. It has been proposed that the gas is discharged from a formed discharge port. For example, in 1986
Japanese Patent No. 118928 discloses a conventional technology regarding a soundproofing device for a small generator. In this prior art, an engine and a generator are covered with a soundproof case, and an engine cooling air outlet is formed in the upper part of one end of the soundproof case, and a cooling air inlet is opened in the soundproof cover opposite to the outlet, and a cooling air inlet is formed in the soundproof cover. On the other hand, it is characterized in that a cooling air outlet is formed that opens toward the lower part of the center, and a muffler for the engine is disposed therein.

However, in this prior art, since the cooling air inlet is opened at the front side of the soundproof case, the sound inside the soundproof cover leaks to the front side and becomes noise. Furthermore, since the cooling air outlet is formed at the top of one end of the soundproof case, the vicinity of the outlet is exposed to the high temperature cooling exhaust air, resulting in an increase in the temperature of the soundproof case.

The present invention was developed in view of these circumstances, and provides an engine with a structure in which a forced air-cooled engine and a generator are disposed within a soundproof case, and cooling air is sucked into the soundproof case to cool the engine and generator. In the drive generator, the internal sound does not leak from the cooling air inlet and becomes a noise, the soundproof case can be cooled, the strength and appearance are good, and the dust etc. is not sucked in. The purpose of the present invention is to provide a cooling device for an engine-driven generator that has good dustproof properties and can be firmly attached to a soundproof case.

In order to achieve the above object, a cooling device for an engine-driven generator according to the present invention includes a forced air cooling engine and a generator mounted on a base plate in a soundproof case, and an output shaft of the engine and a rotor drive shaft of the generator. a fan is attached to a directly connected shaft between the engine and the generator, a volute chamber is formed between the engine and the generator in which the fan is disposed, and a baffle plate surrounds the outer periphery of the engine. providing an engine cooling air passage inside the baffle plate, and providing a bearing plate having an air baffle port on the opposite side of the generator from the engine;
The engine cooling air passage and the air guide port are connected to the volute chamber, and the fan is configured to draw cooling air from the engine cooling air passage and the air guide port side into the volute chamber, and the side surface of the base plate and the soundproof case A downward cooling air inlet is formed with the cooling air inlet, and at least a position of the cooling air flowing in from the cooling air inlet flows down along the inside of the soundproof case. An exhaust duct is provided on one side of the volute chamber while communicating with an engine cooling air passage and an air guide port, and a part of the exhaust duct is formed with an exhaust port communicating with the volute chamber. The engine muffler is disposed inside the wind duct facing the exhaust port, while the exhaust duct is located away from the engine and the fan and has an exhaust port that communicates with the outside of the soundproof case. It is a feature.

The present invention will be explained in detail below with reference to the drawings.

1 to 5 show a first embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view of an engine-driven generator, FIG. 2 is a front view of the engine-driven generator, and FIG. Figure 4 is a plan view of Figure 1 with the tank omitted, Figure 4 shows the arrangement of the volute chamber, muffler, etc. between the engine and fan, as shown in Figure 1, and a cross-sectional view of only the exhaust duct, Figure 5 is a bottom view of FIG. 1;

In these figures, numeral 1 is a soundproof case, 2 and 3 are a forced air-cooled engine and a generator housed and arranged inside this soundproof case 1, and the rotor drive shaft 5 of the generator 3 is connected to the output shaft 4 of the engine 2. It constitutes a generator that is directly connected to the engine. The engine output shaft 4 is connected to the engine 2 midway.
The first tapered portion 4a has a first tapered portion 4a whose diameter expands toward the side, and a second tapered portion 4b whose diameter similarly expands toward the engine 2 at the distal end.
A male threaded portion 4c is located at the front (on the opposite side of the engine) adjacent to the
is formed. A boss portion having a tapered bearing port of a fan 6 which also serves as a flywheel is fitted into the first tapered portion 4a of the engine output shaft 4, and a key is engaged therein. A nut 7 is screwed onto the externally threaded portion 4c, and the fan 6 is pressed and crimped in the diametrically expanding direction of the first tapered portion 4a to be fixed therein. Further, the rotor drive shaft 5 of the generator 3 is formed in a hollow shape penetrating in the axial direction, and its engine side end opening 5a is connected to the second tapered portion 4b of the engine output shaft.
It is formed in a tapered shape that widens toward the end surface so as to coincide with the end face. This tapered opening 5a is fitted with a second tapered portion 4b of the engine output shaft 4, and a screw hole 4d communicating with the hollow of the rotor drive shaft 5 in the central axis direction of the second tapered portion 4b.
is formed. Then, a bolt 7a is screwed into the hollow of the rotor drive shaft 5 from the end surface of the rotor drive shaft 5 on the side opposite to the engine, and the tip of the bolt 7a is inserted into the rotor drive shaft 5.
The engine output shaft 4 fitted into the tapered opening 5a of
The second tapered part 4b is screwed into the screw hole 4d of the second tapered part 4b, and the second tapered part 4b is pulled toward the tapered opening 5a so that both tapered parts are bitten, thereby firmly connecting the engine output shaft 4 and the rotor drive shaft 5. It is designed to be connected. A cooling air passage 13 is formed between the soundproof case 1 and the crankcase 11, oil pan 8, cylinder 12, and generator 3 of the engine 2, which are appropriately narrowed. On the other hand, an air intake port 15 of an air cleaner 14 disposed on the side of the engine 2 is exposed from the soundproof case 1 facing the air cleaner 14, and is designed to take in outside air. In addition, the air intake port 15 is connected to the soundproof case 1.
It may be configured to open inward to suck in the cooling air sucked into the soundproof case 1.

The outer periphery of the cylinder 12 of the engine 2 is a baffle plate 1
6, forming an engine cooling air passage 17 which is divided and communicated with the cooling air passage 13. Further, a volute chamber 19 is formed between the engine 2 and the generator 3, which is separated from the cooling air passage 13 by a baffle plate 18, and this volute chamber 19 communicates with the engine cooling air passage 17. A fan 6 screwed onto the engine output shaft 4 is disposed within the volute chamber 17.
Further, a bearing plate 20 is disposed on the opposite side of the generator 3 to support the rotor drive shaft 5 via a bearing, and the upper part of the bearing plate 20 extends toward the engine side to support the stator. 21 is supported and attached to the outer periphery on the side opposite to the engine. Further, an inlet 22 is opened in the bearing plate 20 to communicate the inside of the generator 3 with the cooling air passage 13. On the other hand, the engine side of the generator 3 is open and communicated with the volute chamber 19. Incidentally, near the inlet 22 of the bearing plate 20, electrical components 23 that do not tolerate high temperatures, such as semiconductors for controlling the generator, are arranged, and are cooled by the cooling air flowing into the generator 3 from the cooling air passage 13. It's becoming like that.

The volute chamber 19 has a diameter that expands toward the outlet side, and the exhaust duct 24 is located at the volute chamber 19 position so that the air guide plate 18 on the side of the outlet opens and closes the opening. It is arranged in a long shape inside the soundproof case extending from the opposite side of the generator 3 to the engine side. The exhaust duct 24 has an exhaust port 25 at a position opposite to the upper part of the fan 6 on the back side of the exhaust duct 24.
4, an engine muffler 26 is disposed so as to face the exhaust port 25 and have a bottom surface substantially along the inner wall shape of the volute chamber 19, and the muffler 26 constitutes a part of the front volute chamber shape; The muffler 26 is configured to prevent the exhaust port 25 of the volute chamber 19 from being blocked or to become a resistance, so that the cooling exhaust air can flow out well. Further, the muffler 26 has a plurality of cooling fans 27 formed on its bottom surface in the streamline direction of the cooling exhaust air.

On the other hand, the exhaust duct 24 has an exhaust outlet 28 that communicates with the outside of the soundproof case 1 on its front side and at a position away from the engine 2 and the fan 6. A tail pipe 29 of the muffler 26 is extended and opened.

The soundproof case 1 is composed of a front plate 30, side plates 31, 32, and a rear plate 33, and has a lower end so that the engine 2 and generator 3, which are disposed on a substantially rectangular base plate 34, are surrounded from the sides. is fixed in contact with the side surface of the base plate 34. Further, a fuel tank 35 is disposed at an opening at the upper end of the soundproof case 1 so as to close this opening.

The four side surfaces of the base plate 34 are as follows:
A recess is formed with a small portion left on both ends of the side surface portion, and the lower end of the soundproof case 1 is brought into contact with and fixed with screws, and a cooling air introduction passage 36 is provided between the recess and the soundproof case 1. and communicates with the cooling air passage 13 inside the soundproof case 1. The opening of the cooling air introduction passage 36, that is, the space between the recess of the base plate 34 and the soundproof case 1 forms a downward slit-shaped cooling air introduction port 37.

In addition, the reference numeral 38 in the figure is an ignition coil, 3
9 is a recoil starter, 40 is a rotor, and 41 is a leg piece.

In such a configuration, when the fan 6 rotates due to the drive of the engine 2, the cooling air flows through the cooling air introduction passages 36... formed by the four concave portions of the base plate 34 and the soundproof case 1.
The air flows into the cooling air passage 13 inside the soundproof case 1 through the air. The direction of the cooling air flowing into the soundproof case 1 is regulated by the cooling air introduction passages 36, so that the front plate 3
0, side plates 31, 32, rear plate 3
Go up inside the soundproof case 1 along the inside of 3,
During this rise, the soundproof case 1 composed of the front plate 30, side plates 31, 32, and rear plate 33 is cooled, and the rising cooling air comes into contact with the fuel tank 35, causing the fuel tank 35 to cool down. cooled down.

Then, a part of it is connected to the cylinder 1 by the air guide plate 16.
2 Engine cooling air passage 1 formed by surrounding the outer periphery
7, cools the cylinder 12, and is sucked into the volute chamber 19.

Further, a part of the cooling air flowing into the soundproof case 1 from the cooling air inlet 37 on the engine 2 side cools the ignition coil 38, the outer periphery of the stator 21, etc. by flowing through the cooling air passage 13. Also, ventilate the area. Further, a part of the cooling air that has flowed into the soundproof case 1 from the cooling air inlet 37 on the side of the generator 3 flows into the generator 3 through the air guide port 22 of the bearing plate 20, and after cooling the generator 3. It is sucked into the volute chamber 19.

In this way, the fan 6 sucks cooling air into the volute chamber 19 from both the engine 2 side and the generator 3 side, cooling the necessary parts and ventilating the inside of the soundproof case 1. .

On the other hand, the cooling exhaust air sucked into the volute chamber 19 flows into the exhaust duct 24 from the outlet 25 of the volute chamber 19 . At this time, the cooling exhaust air flows into the exhaust duct 24 along the bottom surface of the muffler 26, which is inside the exhaust duct 24 and forms a part of the volute chamber shape, and efficiently cools the muffler 26.
The cooling exhaust air that flows into the exhaust duct 24 and cools the muffler and the muffler tail pipe 29 is discharged to the outside from the exhaust air outlet 28. The sound inside the soundproof case 1 is directed downward to the cooling air introduction passage 36.

FIG. 6 shows a second embodiment of the present invention, which is a bottom view of an engine-driven generator. Note that parts and members corresponding to those in FIGS. 1 to 5 are designated by the same reference numerals.

In this embodiment, a resilient filter 42, for example, made of urethane foam, is provided in the cooling air introduction passage 36 in the first embodiment. The filters 42 are fixed by the recesses of the base plate 34 and the soundproof cover 1 against the elasticity thereof. In such a configuration, the soundproof case 1 is cooled and the soundproof case 1 is cooled by the same effect as in the first embodiment.
In addition to directing the internal sound downward, dustproofing is improved because dust is not sucked in from the cooling air inlet, and the elasticity of the filter 42 makes the soundproof case 1
Since a biasing force is applied between the base plate 34 and the base plate 34, the soundproof case 1 can be firmly attached.

In the first and second embodiments, instead of forming the recess in the base plate, an outward protrusion may be formed in the soundproof case to provide a cooling air introduction passage. That is, it is sufficient that the base plate and the soundproof case form a cooling air introduction passage, and the cooling air introduction port is formed downward, and is not limited to the shape of the embodiment.

As explained above, according to the present invention, the cooling air introduction passage is composed of the side surface of the base plate and the soundproof case, and the cooling air introduction port is directed downward.
Compared to a case where the cooling air inlet is opened on the side of the soundproof case, sound will not leak and become a noise, and at least a part of the cooling air flowing in from the cooling air inlet will be absorbed by the soundproof case. Since it is configured to flow down along the inside, it is possible to cool each of the front cover, side cover, and rear cover that make up this soundproof case.
Further, since holes for cooling air inlets are not directly formed in the soundproof case, the strength of the soundproof case can be improved and the appearance is also good. Furthermore, if a resilient filter is installed in the cooling air intake passage, dustproofness can be improved without sucking dust etc. from the cooling air intake, and the installation of the soundproof case can be strengthened, making it easier to remove. It can have a positive effect.

[Brief explanation of drawings]

1 to 5 relate to a first embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view of an engine-driven generator, FIG. 2 is a front view of the engine-driven generator,
Figure 3 is a plan view of Figure 1 with the soundproof case cut away and the fuel tank omitted, and Figure 4 approximately shows the arrangement of the volute chamber, muffler, etc. between the engine and fan in Figure 1, and the exhaust air. A cross-sectional view of only the duct,
5 is a bottom view of FIG. 1, and FIG. 6 is a bottom view of an engine-driven generator according to a second embodiment of the present invention. 1... Soundproof case, 2... Engine, 3... Generator, 4... Output shaft, 6... Fan, 19...
...Volume chamber, 24...Exhaust duct, 25...
Exhaust port, 26...muffler, 28...exhaust outlet,
34...Base plate, 36...Cooling air introduction passage, 37...Cooling air introduction port, 42...Filter.

Claims (1)

[Scope of utility model registration request] A forced air-cooled engine and a generator are mounted on a base plate and arranged in a soundproof case, the output shaft of the engine is directly connected to the rotor drive shaft of the generator, and a fan is connected to the directly connected shaft between the engine and the generator. A volute chamber is formed between the engine and the generator in which the fan is installed, and a baffle plate is provided surrounding the outer periphery of the engine, and the inside of the baffle plate is used as an engine cooling air passage. A bearing plate having an air guide port is provided on the side opposite to the engine, and these engine cooling air passages and air guide ports are communicated with the volute chamber, and the cooling air is directed from the engine cooling air passage and the air guide port side to the volute by the fan. A cooling air inlet facing downward is formed by the side surface of the base plate and the soundproof case, and at least a position of the cooling air flowing from the cooling air inlet is inside the soundproof case. The cooling air inlet is connected to the engine cooling air passage and the air guide port, and an exhaust duct is provided on one side of the volute chamber, and a part of the exhaust duct is configured to flow downward along the engine cooling air passage. An exhaust port communicating with the volute chamber is formed in the exhaust duct, and an engine muffler is disposed within the exhaust duct facing the exhaust port, while the exhaust duct is located away from the engine and the fan.
A cooling device for an engine-driven generator, characterized in that an exhaust air outlet is formed that communicates with the outside of the soundproof case.