JPH11343859A - Portable engine generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain excellent cooling effect while attaining miniaturization by providing the introducing port of a cooling air passage leading sucked cooling air to the stator part and the muffler part of a generator in the vicinity of the control unit of the generator so as to introduce air after passing through the control unit into the cooling air passage. SOLUTION: The interior of a portable engine generator is divided into an engine arranged space and a generator arranged space with a fan casing 21, and by rotating a first cooling fan 20 integratedly provided with the crankshaft 12B of an engine 12, cooling air is sucked from slit-like cooling air sucking ports 34 provided on the bottom face of a sound-proof front cover 2, to cool the main parts of the engine 12 such as a cylinder 12A. By rotation of a second cooling fan 29 fitted to the outer circumferential face side 26a of a rotor supporting plate 26 opposite to a shroud 31, cooling air sucked from a suction port 35 cools a control circuit unit 28, a stator coil 27, a muffler, and the like, and then the air is discharged outward through a duct.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable engine generator, and more particularly to a soundproof portable engine generator in which a whole unit including an engine and a generator driven by the engine is housed in a soundproof cover. Cooling structure.

[0002]

2. Description of the Related Art A soundproof portable engine generator in which an entire unit including an engine and a generator driven by the engine is housed in a soundproof cover is required to be small, light, and low in noise. It is necessary to avoid the influence of heat on the generator parts such as the generator-side stator and the control circuit unit for performing various controls and electrical components. However, it is necessary to smoothly achieve the two opposing effects of cooling efficiency and compactness. Is difficult. For this reason, various techniques aiming at smoothly achieving the two opposing effects have been proposed.

For example, in a forced cooling device for a soundproof portable generator disclosed in Japanese Utility Model Application Laid-Open No. 59-4162, a first cooling fan is attached to a shaft of the generator, and a back-to-back is attached to a crankshaft side of an engine located on the opposite side of the shaft. Are provided with second and third cooling fans, and a wind guide plate is provided to form a wind guide path communicating with the generator and the engine, respectively, to enhance the cooling effect of the generator, the engine and the muffler. The structure of the road and the like is complicated, and there are problems in miniaturization, weight reduction, cost reduction, and the like.

Further, in the engine generator disclosed in Japanese Patent Application Laid-Open No. 55-139054, a first cooling air passage for cooling a muffler after cooling a cylinder portion with a first cooling fan provided on an engine crankshaft, and a power generator. The second provided on the rotor shaft of the machine
The second cooling air passage for cooling the generator with the cooling fan,
Although the cooling effect of the generator, the engine, and the muffler is enhanced by forming the two cooling air passages, there are problems in miniaturization, weight reduction, and the like. In particular, none of the above-mentioned technologies considers cooling of electrical components such as a control circuit unit in which the influence of heat must be avoided most.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention smoothly achieves two opposing effects of miniaturization, weight reduction and high cooling efficiency, as well as a stator and various controls on the generator side. The present invention relates to a portable engine generator capable of effectively cooling a control circuit unit and the like for performing the above, and an object thereof is to provide a soundproof portable engine generator.

[0006]

According to the first aspect of the present invention,
A portable engine generator including an engine and a generator driven by the engine, wherein a first cooling fan is provided on a crankshaft side of the engine, and a second cooling fan is provided on a rotor side of the generator. A first cooling air passage for guiding cooling air sucked by the first cooling fan to the cylinder portion and discharging the cooling air to the outside, and cooling the cooling air sucked by the second cooling fan to cool the stator portion of the generator. A second cooling air passage which is guided to a muffler section and discharged to the outside, and a cooling air inlet of the first or second cooling air passage is arranged near a control unit of the generator, The air after passing through the control unit is configured to be guided to at least one of the first and second cooling air passages.

According to the invention, since the control unit, which is expected to be thermally weakest because of having the electronic components, is arranged near the cooling air inlet, immediately after the intake having the highest cooling effect. Can be passed through the control unit.

Further, the present invention is the same as Japanese Patent Application Laid-Open No. 55-139054 in that two cooling air passages are formed. Instead of cooling the muffler after cooling the cylinder portion with the first cooling fan provided on the crankshaft, in the present invention, the muffler portion is cooled after the stator portion of the generator is cooled by the second cooling fan. It is different in that it is configured as follows.

That is, since the cooling heat capacity of the cylinder portion is sufficiently larger than that of the stator portion of the generator, the muffler is sufficiently cooled because the cooling air after passing through the cylinder portion has already been heated to a considerably high temperature. It is difficult. Since the first cooling air after passing through the cylinder portion is already at a considerably high temperature, it is discharged to the outside as it is and the muffler portion is cooled by the second cooling air after cooling the stator portion of the generator having a sufficient cooling capacity. Is configured to be cooled. In terms of the cooling heat balance, the cooling air inlet of the second cooling air passage is
Preferably, it is located near the control unit of the generator.

According to a second aspect of the present invention, in the soundproof portable engine generator according to the first aspect, the whole unit including the engine and the generator driven by the engine is housed in a soundproof cover. In the second cooling air passage, a wind guide passage for guiding the cooling air after cooling the stator portion of the generator to the muffler portion is defined by the inner wall surface of the soundproof cover at least one side from the first cooling air passage. It is characterized by being formed by a duct-shaped passage formed.

As described in the first aspect, it is preferable that the muffler portion is cooled by the second cooling air after cooling the stator portion of the generator, from the viewpoint of cooling and heat balance. However, since the stator part is located on the generator side and the muffler part is located on the engine side,
It is difficult to cool both efficiently. Accordingly, the first aspect of the present invention is to form a duct for guiding cooling air after cooling the stator portion of the generator to the muffler portion by a duct-like passage.
The feature of. Thus, the second cooling air after the cooling of the stator portion can be effectively guided to the muffler portion.

The duct-like passage is formed independently of the inner wall surface of the soundproof cover without being formed independently, so that the duct-like passage can be easily formed without providing a special space. Two opposing effects of miniaturization, weight reduction and high cooling efficiency can be smoothly achieved. That is, since the duct includes the wall surface of the soundproof cover on one side of the closed cross section, the number of members for forming the closed cross section can be reduced, the configuration can be simplified, and the weight can be reduced.

The invention according to claim 3 is characterized in that the control unit is disposed so as to face the cooling air inlet, and a heat radiating portion of the control unit is located on the side of the facing position. According to this invention, since the heat radiating portion of the control portion collides directly with the cooling air having the highest cooling effect immediately after passing through the cooling air inlet, the effect of claim 1 is further enhanced.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will now be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, and are merely illustrative examples. Only.

FIGS. 1 to 8 show a portable engine generator according to an embodiment of the present invention. The external appearance of the generator is shown in FIGS. 1 and 2, the internal structure is shown in FIGS. FIGS. 7 and 8 show the structure, and FIGS. 4 to 6 show the flow of the cooling air.

FIG. 1 is a front view of a portable engine generator, and FIG. 2 is a side view thereof. In FIGS. 1 and 2, 1 is a portable engine generator, 2 is a cover before soundproofing, 3 is a cover after soundproofing. The two soundproof covers 2 and 3 are both formed of a mold made of synthetic resin. The soundproof covers 2 and 3 are integrally assembled with a plurality of screws 4 and have handles 11 formed integrally with the soundproof covers 2 and 3 respectively. 7 is a recoil starter, 8 is a throttle lever, 9 is a fuel cock, 10
Is a leg of the portable engine generator 1, and both soundproof covers 2,
3 is attached to the lower surface.

Next, the configuration of each of the soundproof covers 2 and 3 will be described. FIG. 8 is a perspective view of the front cover 2 when viewed from the inside. A slit-shaped cooling air suction port 34 mainly sucked by the first cooling fan 20 is provided on the bottom surface, and faces the engine cylinder 12A. A first exhaust port 5 for exhausting the engine cooling exhaust air after cooling the engine cylinder 12A is located at an upper left position on the front of the cover, and a second exhaust port is located on the side of the cover adjacent to the first exhaust port 5. An outlet 6 is provided. Below the first discharge port 5 and the second discharge port 6, a horizontal partition plate 36B which forms a part of the bottom surface of the duct 33 described later extends in the horizontal direction. In addition, 1 in the figure
7A is a storage recess of the cassette fuel cylinder, and 7a is a recoil rope insertion hole.

FIG. 7 is a perspective view of the cover 3 from the inside after the soundproofing. The slit-shaped cooling air inlet 35 mainly sucked by the second cooling fan 29 is provided on the bottom surface and the side thereof.
A second cooling exhaust air B, B ′ after cooling the control circuit unit, the stator coil 27 and the muffler 15 via the shroud 31 and the duct 33 can be exhausted from the second exhaust port 6 through the shroud 31 and the duct 33. It is configured. At the center of the rear surface of the cover 3 after the soundproofing, a shroud 31 that covers the stator 27 and forms the air guide passage 32 is provided. The shroud 31 has a circular cylindrical shape, and has an opening 32a on a side portion thereof. It communicates with the duct 33.

On the cover 3 side after the soundproofing, the duct 33 has a vertical partition plate 36 vertically suspended from the upper surface of the cover, a side wall 301 forming a part of the outer wall of the cover, and a bottom surface which is curved horizontally with the side wall 301 facing inward. 302 forms a first duct space 33A on the cover 3 side after soundproofing. On the other hand, the duct space 33A on the side of the cover 3 after the soundproofing is the second duct space 33 which also functions as a muffler storage space on the side of the front cover 2.
Connected to B.

As shown in FIG. 6, the second duct space 33B abuts the side wall 201 forming a part of the outer wall of the front cover 2 and one side thereof to the vertical partition plate 36 on the rear cover side with the muffler 15 interposed therebetween. And the gasket plate 37 extending on the other side to the second discharge port 6 and the horizontal partition plate 3 extending on the bottom surface 302 thereof.
6B, the shroud 31, its side opening 3
2a, the duct 33 (the first duct space 33A + the second duct space 33B) and the second discharge port 6 form a second cooling air passage.

Next, the internal structure of the portable engine generator will be described with reference to FIGS. 3 shows a left side view of FIG. 2 in which the cover after soundproofing on the generator side is removed, and FIG. 4 shows a central cross sectional view of FIG. 2 and a top plan view of FIG. Figures 3-5
In the figure, reference numeral 12 denotes an engine erected in a space on the right side of the casing via a vibration-proof rubber 10A, and a cylinder 12A portion faces the first discharge port 5. Reference numeral 13 denotes a vaporizer, 14 denotes an air cleaner, 15 denotes a muffler.
5 is provided in the duct 33. 16 is cylinder 1
An addition plug attached to the top of 2A, 17 is a cassette fuel cylinder, 18 is a fuel pipe, 19 is an oil tank, and oil is supplied into an intake passage downstream of the carburetor 13 by an oil pump (not shown). A clutch 22 is attached to the first cooling fan 20. The first cooling fan 20 is housed in a fan casing 21 of the engine 12, rotates integrally with the crankshaft 12B, and forms a first cooling air passage for cooling a main part of the engine 12 such as the cylinder 12A.

That is, as shown in FIG. 6, a fan casing 21 substantially divides an engine arrangement space and a generator arrangement space described later, and is provided on the bottom surface of the soundproof front cover 2 by suction rotation of the first cooling fan 20. The first cooling air is sucked from the slit-shaped cooling air suction port 34, and the inside of the fan casing 21 and the gasket plate 37 (the duct 33).
After cooling the cylinder 12A and the like while being guided along the outer side wall), the first air discharged from the first outlet 5 to the outside is discharged.
Is formed.

Reference numeral 22a denotes a clutch drum, 23 denotes a rotor shaft integrated with the clutch drum 22a, 24 denotes a bearing of the rotor shaft 23, and 25 denotes a generator, which is a disk-shaped shaft mounted on the rotor shaft 23. (Rotor) 26 attached to the rotor support plate 26a of the first embodiment, and a stator coil (stator) 27 fixedly supported by the outer periphery of the bearing 24.
Consists of

Reference numeral 28 denotes a control circuit unit, which is a cover 3 after soundproofing.
Below the generator, is disposed in a lower space facing the slit-shaped cooling air intake ports 35, 35a provided on the cover bottom surface and on the side thereof, and the second cooling fan 29 rotates so that the cooling air intake ports 35, 35 The cooling air sucked from 35a is attached so as to directly (first) cool the control circuit unit 28, and the lower surface facing the cooling air suction port 35 is formed by a heat dissipation plate 28a.

The second cooling fan 29 is attached to the outer peripheral surface of the rotor support plate 26a facing the shroud 31,
It is configured to be rotatable integrally with the rotor shaft 23. 3
Numeral 0 denotes a cooling air passage which penetrates the space between the stator coil (stator) 27 and the shroud 31 air guiding space 32 via the second cooling fan 29, and 31 denotes a fan casing of the second cooling fan 29. The shroud also functions, and is integrally formed with the cover 3 after soundproofing as described above. Reference numeral 32 denotes a circular cooling air guide space provided on the inner peripheral surface side of the shroud (fan casing) 31 and communicates with the duct 33 through a side opening 32a.

Reference numeral 36 denotes a vertical partition plate (internal partition) forming the duct 33, and reference numeral 37 denotes a muffler gasket plate having a structure which also serves as an internal partition together with the vertical partition plate 36. The duct 33 is formed by a side wall 301 forming a part of the outer walls of the soundproof covers, a bottom surface 302 curved horizontally with the side wall 301 of the cover after the soundproof inward, and a horizontal partition plate 36B. A space 33A + a second duct space 33B) is formed, and the cooling air suction ports 35, 35a,
Control circuit unit 28 space, stator coil 27 space, cooling air passage 30, shroud air guiding space 3
2. As described above, the second cooling air passage is formed by the side opening 32a, the duct 33, and the second discharge port 6 (see FIG. 6), and the control is performed by the second cooling air passage. Generator 2 such as circuit unit 28 and stator coil 27
5, and the muffler 15 can be sequentially cooled.

Next, the operation of the portable engine generator will be described. With the fuel cock 9 open, the recoil starter 7
To start the engine 12. After the engine 12 is started, the engine speed is increased by the throttle lever 8 to increase the clutch-in speed, and the clutch 22 and the clutch drum 22a are connected. When the clutch 22 and the clutch drum 22a are connected, the crankshaft 12B on the engine 12 side, the first cooling fan 20, the generator The rotor shaft 23 and the rotor 26 on the 25 side rotate integrally and the generator 25 starts power generation. At the same time, the first cooling fan 20
As shown in FIGS. 4 and 6, the first cooling air flows along a flow line indicated by arrow A in FIG. 4 mainly from a cooling air suction port 34 provided on the bottom surface of the soundproof covers 2 and 3. And cools the main part of the engine 12 such as the cylinder 12A while being guided along the fan case 21. Thereafter, as shown by the arrow A in FIG. 5 and FIG. ) Is discharged to the outside from a cooling exhaust outlet (first exhaust port) 5.

In the second cooling air passage B → B ′, the cooling air sucked from the cooling air suction ports 35 and 35a is directly radiated by the cooling air suction ports 35 and 35a by the rotation of the second cooling fan 29 mounted on the rotor shaft 23. After the control circuit unit 28 is cooled by contacting (at first) 28a, the space is provided through the stator coil 27 arrangement space, the cooling air penetration port 30, the shroud 31 ventilation space 32, the side opening 32a, and the duct 33. After cooling the muffler 15, it is discharged from the second outlet 6 to the outside.

Therefore, according to this embodiment, the first cooling air passage A for cooling the main part of the engine 12 such as the cylinder, the generator 25 such as the control circuit unit 28 and the stator coil 27, and the muffler 15 are cooled. By forming the second cooling air passages B and B ', it is possible to reduce the bottom noise by the soundproof covers 2 and 3 and at the same time to enhance the cooling effect of the electric system of the generator 25 and the muffler, thereby avoiding various effects due to heat. In addition, since the soundproof covers 2 and 3 are all molded products made of a resin material, the weight can be reduced.

[0030]

As described above, according to the first and third aspects of the present invention, the muffler and the like can be effectively cooled together with the generator-side stator and the control unit for performing various controls. According to the second aspect of the present invention, two opposing effects of miniaturization, weight reduction and high cooling efficiency can be smoothly achieved, which is particularly advantageous for a soundproof portable engine generator.

[Brief description of the drawings]

FIGS. 1 to 8 show a portable engine generator according to an embodiment of the present invention, and FIG. 1 is a front view of the portable engine generator.

FIG. 2 is a side view of the portable engine generator of FIG.

3 to 5 show the internal structure of the portable engine generator shown in FIG. 1, and FIG. 3 is a left side view of FIG. 2 in which a cover after soundproofing on the generator side is removed.

FIG. 4 is a cross-sectional view at the center in FIG. 2, and particularly a cross-sectional view of a main part passing through a crankshaft.

FIG. 5 shows an internal plan view of the generator after removing the cover after soundproofing.

FIG. 6 is an operation diagram showing a flow of a second cooling air, and particularly shows a configuration of a duct in a perspective view.

FIG. 7 is a perspective view of the cover after soundproofing viewed from the inside.

FIG. 8 is a perspective view of the soundproofing front cover as viewed from the inside.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Portable engine generator 2 Cover before soundproofing 3 Cover after soundproofing 5 First outlet 6 Second outlet 12 Engine 15 Muffler 27 Stator coil 28 Control circuit unit 29 Second cooling fan 31 Shroud 32a Side opening 33 Duct 34 Cooling air suction port 35, 35a Cooling air suction port 36 Vertical partition plate 36B Horizontal partition plate 37 Gasket plate 301 Side wall forming part of rear cover outer wall 302 Side wall bottom surface 201 Side wall forming part of front cover outer wall A First Cooling air passage B, B 'second cooling air passage

Claims (3)

[Claims] 1. A portable engine including an engine and a generator driven by the engine, wherein a first cooling fan is provided on a crankshaft side of the engine and a second cooling fan is provided on a rotor side of the generator. In the generator, a first cooling air passage for guiding cooling air sucked by the first cooling fan to a cylinder portion and discharging the cooling air to the outside, and a cooling air sucked by the second cooling fan to a stator of the generator. A second cooling air passage for guiding the muffler to the outside after cooling the cooling air passage, and a cooling air inlet of the first or second cooling air passage near the control unit of the generator. Wherein the air after passing through the control unit is guided to at least one of the first and second cooling air passages. 2. The soundproof portable engine generator according to claim 1, wherein the entire unit including the engine and the generator driven by the engine is housed in a soundproof cover. Among them, a wind guide path for guiding the cooling air after cooling the stator part of the generator to the muffler part has at least one side of the inner wall surface of the soundproof cover, and is formed by a duct-like passage partitioned from the first cooling wind passage. A portable engine generator characterized by being formed. 3. The portable device according to claim 1, wherein the control unit is disposed so as to face the cooling air introduction port, and a heat radiating portion of the control unit is located on the facing position. Engine generator.