JP7463040B2 - Internal cooling structure for portable work equipment - Google Patents

Description

The present invention relates to an internal cooling structure for portable working machines such as engine-driven generators, welding machines, and portable fuel cell power generation devices, and in particular to an internal cooling structure for portable working machines suitable for portable fuel cell power generation devices.

Portable work machines such as engine-driven generators, welding machines, and fuel cell portable power generation devices house the engine, work machine body, etc. in a housing, and cool air is circulated inside the housing to cool the engine and work machine body that generate heat. For example, in the fuel cell power generation device shown in Patent Document 1, the inside of a square box-shaped housing is divided by a partition into an electrical chamber that houses the control device, inverter, etc., and a main body chamber that houses the fuel cell main body, and air intakes are provided on the bottom of both the electrical chamber and the main body chamber.

The electric chamber fan installed inside the electric chamber draws outside air into the electric chamber through an air intake port installed on the bottom surface of the electric chamber, which cools the control device, inverter, etc. stored inside the electric chamber, and then leads it from the electric chamber into the main body chamber through the gap in the partition. The fuel cell main body stored in the main body chamber is cooled by air drawn in from the air intake port installed on the bottom surface of the main body chamber together with the air led from the electric chamber through the gap in the partition, and the cooled air is discharged to the outside by the main body chamber fan installed inside the main body chamber. In this way, efficient ventilation with little stagnant air is achieved.

In engine-driven work machines such as engine generators, the square box-shaped housing that houses the engine and the work machine body has intake ports on the sides and back, and an exhaust port on the front top. Air is sucked in from the intake ports and circulated throughout the inside of the housing, and then exhausted to the outside from the exhaust port. In this way, the engine and the work machine body are cooled.

JP 2007-200650 A

However, among the internal cooling structures of the above-mentioned conventional portable working machines, in the case of the above-mentioned portable working machine and engine working machine, in which the engine and the working machine body are housed in a square box-shaped housing, the cooling air flows inside the square box shape, and the air flow becomes turbulent in the corners inside the housing, which causes the problem of inefficient cooling. In addition, in the case of the one shown in Patent Document 1, the air intakes are provided on the bottom of the electrical chamber and the main body chamber, so in order to ensure a sufficient amount of intake air, the device needs to be raised, which increases the size in the vertical direction and limits the installation space.

In consideration of these problems, the present invention aims to reduce turbulence in the flow of cooling air within the work machine, thereby increasing the cooling efficiency, and to ensure a sufficient amount of intake air without raising the height of the device.

In order to solve the above problem, the invention of claim 1 of the present application is characterized in that semi-cylindrical frames are erected facing each other at both longitudinal ends of a housing that houses the working machine body so that the entire housing has an oval shape when viewed from above, an air intake port is provided on one surface of the frames and an exhaust port is provided on the other surface of the frames , and cooling air is allowed to flow from the air intake port to the exhaust port along the curved surface inside the housing.

The invention according to claim 2 of the present application is characterized in that, in the invention according to claim 1, the intake port and exhaust port are provided with multiple parallel louvers, each of which has an arc-shaped tip that follows the outer periphery of the frame, is inclined obliquely downward from the inside to the outside of the housing, and is further rounded downward in a cone shape on the outside.

The invention according to claim 3 of the present application is characterized in that, in the invention according to claim 1 or 2, groove-shaped air guide members with a U-shaped cross section and open ends are arranged in parallel at a predetermined interval in a face-down state across the bottom of the housing, and exhaust openings are provided on the side surfaces of the middle parts of the air guide members so as to face each other, and air sucked in from the openings at both ends of the air guide members is introduced into the housing.

The invention according to claim 4 of the present application is characterized in that in the invention according to claim 3, the inside of the housing is divided into two levels, an upper level and an lower level, a fuel cell unit is arranged as the working machine main body in the upper level, and a power conditioner is arranged in the lower level, and the air discharged from the exhaust opening of the air guide member cools the power conditioner arranged in the lower level of the housing and is then introduced into the upper level of the housing.

The present invention provides the following advantages.
That is, in the invention according to claim 1, semi-cylindrical frames are erected facing each other at both longitudinal ends of a housing that houses a working machine body so that the entire housing is oval when viewed from above, an intake port is provided on one face of the frames and an exhaust port on the other face of the frames , and cooling air flows from the intake port to the exhaust port along the curved surface inside the housing, so that there are no corners where the flow of cooling air is disturbed and the disturbance of the flow of cooling air inside the working machine is reduced, thereby improving the cooling efficiency. Also, by providing the intake port and exhaust port on the surface of the semi-cylindrical frame, the intake port and exhaust port can be made large in the lateral direction, which also improves the cooling efficiency.

In the invention of claim 2, in the internal cooling structure of the portable work machine of claim 1, the intake and exhaust ports are provided with multiple parallel louvers whose tip edges are arc-shaped so as to follow the outer peripheral surface of the frame, and which are inclined diagonally downward from the inside to the outside of the housing and further rounded outward in a cone shape, so that raindrops that try to get in through the intake and exhaust ports fall due to the rounded cone shape of the tip of the louvers, making it difficult for them to get in.

In the invention according to claim 3, in the internal cooling structure of the portable work machine according to claim 1 or 2, groove-shaped air guide members with a U-shaped cross section and open ends are arranged in parallel at a predetermined interval in a face-down position across the bottom of the housing, and exhaust openings are provided opposite each other on the sides of the middle parts of the air guide members, so that air sucked in from the openings at both ends of the air guide members is introduced into the housing. Therefore, when moving the portable work machine, the air guide members can be used as insertion points for the tines of a forklift, and a sufficient amount of intake air can be ensured without raising the device.

In the invention according to claim 4, in the internal cooling structure of the portable working machine according to claim 3, the inside of the housing is divided into two levels, an upper level and an lower level, a fuel cell unit is arranged as the working machine main body in the upper level, a power conditioner is arranged in the lower level, and the power conditioner arranged in the lower level of the housing is cooled by air discharged from the exhaust opening of the air guide member, and then introduced into the upper level of the housing. As a result, in addition to the cooling air that flows from the intake ports provided at both ends of the housing in the longitudinal direction to the exhaust port,
The cooling air used to cool the power conditioner is also introduced from the lower part of the housing, allowing the fuel cell unit to be cooled efficiently.

1 is a diagram showing a fuel cell type portable power generating device according to one embodiment of the present invention; FIG. 2 is a diagram showing the internal structure of the portable fuel cell type power generating device of FIG. FIG. 2 is a diagram showing a front frame and a rear frame. FIG. FIG. FIG. FIG. FIG. FIG. 2 is an assembly diagram of the lower base and the upper base. FIG. 2 is a diagram showing the arrangement of power conditioners in a control device room. FIG. 13 is a diagram showing the state in which the control device room is covered with a rack cover. FIG. 4 is a diagram showing the flow of cooling air inside the portable power generating device.

The following describes in detail an embodiment of the present invention with reference to the drawings.

Figure 1 shows a fuel cell portable power generation device according to one embodiment of the present invention, and Figure 2 shows the internal structure of the fuel cell portable power generation device of Figure 1, showing a view from the oblique front side and a view from the opposite oblique rear side, respectively. In Figures 1 and 2, reference numerals 1 indicate a front frame, 2 indicate a rear frame, 3 indicate a roof panel, 4 indicate a lower base, 5 and 6 indicate side doors, 7 and 8 indicate splasher panels, 9 indicate an intake port, 10 indicate an exhaust port, 11 indicate an intake opening, 12 indicate a generated water outlet, 13 indicate a hydrogen supply port, 14 indicate a hanging hook, 15 indicate a hanging hook cover, 16 indicate an output terminal section, 17 indicate an operation panel, 18 indicate an operation switch, 19 indicate an emergency stop button, 20 indicate an upper base, 21 indicate a hanging bracket, 22 indicate a control box, 23 indicate an electrical equipment box, and 24 indicate a cover.

As shown in Figure 3, the front frame 1 and rear frame 2 are semi-cylindrical, with an intake port 9 provided at the bottom of the rear frame 2 and an exhaust port 10 provided at the bottom of the front frame 1. The sides are covered with side doors 5, 6 and splasher panels 7, 8, and the side doors 5, 6 can be opened and closed by rotating vertically around their upper edges.

The upper part is covered with a roof panel 3. As shown in FIG. 4, the roof panel 3 is semi-cylindrical from front to back with a rounded upper periphery and has a surface on the back for attachment to the front frame 1 and rear frame 2. A hanging hook mounting bracket 3a with a U-shaped cross section is provided across the center of the longitudinal direction, and a hanging hook mounting section 3b for mounting a hanging hook 14 is provided in the center. A hanging hook cover 15 is attached to cover the entire opening of the hanging hook mounting bracket 3a. Furthermore, cover mounting brackets 3c, 3c for covers 24, 24 are provided at one end of the hanging hook mounting bracket 3a.

As shown in Figures 1 and 2, a lower base 4 is provided at the bottom of this fuel cell portable power generation device, and intake openings 11, 11 are provided on both the left and right sides of the lower base 4, so that cooling air can be introduced into the interior not only through the intake port 9 but also through the intake openings 11, 11.

The upper base 20 is disposed on the lower base 4, and a fuel cell unit (not shown) is disposed on the upper base 20. A control box 22 and an electrical equipment box 23 for the fuel cell unit are disposed on one side of the upper base 20, and covers 24, 24 are disposed on the other side, so that air drawn in from the intake port 9 flows between the control box 22, electrical equipment box 23 and covers 24, 24, cooling the fuel cell unit between them, before being discharged from the exhaust port 10.

The lower ends of the hanging fittings 21, 21 are attached to the center of both sides of the lower base 4, and the hanging hook 14 is attached to the upper ends of the hanging fittings 21, 21 via the hanging hook mounting fitting 3a. The hanging hook 14 is always covered by the hanging hook cover 15.

Inside the intake port 9, an intake duct 9a with a U-shaped cross section is provided, and as shown in FIG. 5, multiple straightening plates 9b, 9b, 9b are provided vertically on its inner surface. Multiple intake louvers 9c, 9c, 9c are attached in parallel to the U-shaped side wall of the intake duct 9a. The intake louvers 9c, 9c, 9c are formed in an arc shape with their leading edges following the outer circumferential surface of the rear frame 2, and as shown in FIG. 6, they are provided so as to slope diagonally downward from the inside to the outside of the housing, and are further rounded downward in a conical shape on the outside.

A frame-shaped exhaust duct 10a is provided inside the exhaust port 10, and as shown in FIG. 7, its inner surface faces the inside of the housing, and there is an opening at the top, with multiple straightening plates 10c, 10c, 10c provided vertically on the lower outer surface of the opening. The opening is covered from the outside with an exhaust duct cover 10b, which is surrounded by trapezoidal plates on the top, left, and right sides and is open on the bottom. As shown in FIG. 8, multiple straightening plates 10g, 10g are provided vertically inside the exhaust duct cover 10b. These straightening plates 10g, 10g are arranged so that they are located between the straightening plates 10c, 10c, 10c provided on the exhaust duct 10a.

In addition, on both sides of the exhaust duct 10a, louver fixing members 10f, 10f with an L-shaped cross section are attached to the underside of the exhaust duct cover 10b, and an exhaust louver upper plate 10e is attached to cover the space between their upper ends, and below that, multiple exhaust louvers 10d, 10d, ... similar to the intake louvers 9c, 9c, 9c described above are attached in parallel at regular intervals.

By providing intake louvers 9c, 9c, 9c like this at the intake port 9 and exhaust louvers 10d, 10d, ... at the exhaust port 10, raindrops that hit each louver fall from the cone-shaped rounded tip of each arc-shaped louver, making it difficult for them to enter through the intake port 9 or exhaust port 10.

Figure 9 is an assembly diagram of the lower base and upper base. The lower base bottom plate 4a of the lower base 4 is oval-shaped with a rectangular middle section and semicircular longitudinal ends, and across the lower base bottom plate 4a, groove-shaped air guide members 4b with a U-shaped cross section and open ends are placed in a face-down position parallel to each other at a specified distance. Exhaust openings 4c are provided on the sides of the middle sections of the air guide members 4b, facing each other.

Also, lower base side plates 4d are provided vertically on both side edges of the lower base bottom plate 4a, and the portions where the air guide members 4b come into contact are open. Also, a lower base front plate 4e is provided vertically on the front side of the lower base bottom plate 4a, and a lower base rear plate 4f is provided vertically on the rear side. Lower base side upper plates 4g, 4g with an L-shaped cross section are provided on the upper part of the lower base side plates 4d, and lower base end upper plates 4h, 4h are provided on the upper parts of the lower base front plate 4e and the lower base rear plate 4f.
We have set up a system.

The left and right lower base side plates 4d, 4d are provided with brackets 4i, 4i for attaching the hanging brackets 21, and one of the lower base side plates 4d is provided with a drain joint 4j for discharging the fuel cell generated water to the outside from the generated water outlet 12 (Figure 1).

The upper base 20 is then placed and attached on top of the lower base 4. The upper base bottom plate 20a of the upper base 20 is formed in an oval shape, similar to the lower base bottom plate 4a, and a ventilation hole 20b is provided in the center of the upper base bottom plate 20a to introduce the cooling air discharged from the exhaust opening 4c of the air guide member 4b upward.

In addition, square pipes 20c, 20c, ... are erected on the bottom plate 20a of the upper base, and the top plate 20d of the upper base is placed and fixed on their upper ends to form a stand. In addition, drain hose insertion holes 20e, 20e are provided at opposing positions on the bottom plate 20a of the upper base and the top plate 20d of the upper base, for passing a hose for treating water generated by the fuel cell.

The space between the upper base bottom plate 20a and the upper base top plate 20d is used as a control device room, in which power conditioners 25, 25, ... for converting the DC voltage generated by the fuel cell into AC voltage and a power conditioner control device 26 are installed, as shown in Figure 10. The space above the upper base top plate 20d is used as a fuel cell unit room, in which a fuel cell unit 30 consisting of a fuel cell stack 30a, an air cleaner 30b, a radiator 30c, a radiator fan 30d, etc. are installed.

The fuel cell stack 30a is where hydrogen supplied from the hydrogen supply port 13 (Figure 1) undergoes a chemical reaction with oxygen in the air drawn in from the air cleaner 30b. The radiator 30c absorbs the heat generated when hydrogen and oxygen react in the fuel cell stack 30a and cools the hot cooling water. The radiator fan 30d is a fan for cooling the radiator 30c, and is placed inside the housing to draw the cooling air from inside the housing to the outside.

The power conditioner 25 is divided into multiple units, each housed in a square box, and each unit draws in air for cooling the power conditioner using a DC fan 25a, cools the inside of the box, and expels the air from an air exhaust port 25b.

Figure 11 shows the state in which the control device room is covered with a stand cover. The reference numerals correspond to those in Figures 5, 8, and 10, with 20f being the stand cover and 20g being the exhaust opening. One side of the stand is covered with stand cover 20f having exhaust opening 20g, and the other side is covered with a back cover (not shown) that has no opening. In addition, the front side of the stand is blocked by exhaust duct 10a, and the rear side is blocked by intake duct 9a.

Therefore, inside the rack, the cooling air introduced through the ventilation holes 20b in the upper base bottom plate 20a cools each power conditioner 25, and then is discharged through the exhaust opening 20g and flows to the upper part where the fuel cell unit 30 is housed.

The flow of cooling air inside the housing is generated by the suction effect of the radiator fan 30d of the fuel cell unit 30. Figure 12 is a diagram showing the flow of cooling air inside the portable power generation device. The flow indicated by F1 in the figure is that outside air is sucked in from the intake openings 11, 11, 11, 11 on the sides of the lower base 4, passes through the exhaust opening 4c of the air guide member 4b and the ventilation holes 20b in the bottom plate 20a of the upper base, and is sent to the control device room in the frame, where it cools the power conditioner 25 and the power conditioner control device 26.

Then, the DC fan 25a of the power conditioner 25 exhausts the cold air F2, F3, and F4 upward from the exhaust openings 20g, 20g of the frame covers 20f, 20f that cover the control device room. The cold air F2 passes from the exhaust opening 20g beside the electrical equipment box 23 and is sent to the fuel cell unit room, where it is also used to cool the fuel cell stack 30a. The cold air F3 and F4 pass from the exhaust opening 20g between the side door 5 and the electrical equipment box 23, enter the fuel cell unit room from the space above the electrical equipment box 23, and are also used to cool the fuel cell stack 30a.

The cold air F5 is taken in through the intake port 9 of the rear frame 2, rectified by the air straightening plate 9b of the intake duct 9a, and introduced into the fuel cell unit room along the inner curved surface of the rear frame 2. After cooling the fuel cell stack 30a and the radiator 30c, it is rectified by the air straightening plates 10g and 10c and, together with the cold air F5 (not shown) that has flowed around the inner curved surface of the front frame 1, is discharged to the outside from the exhaust port 10 as exhaust air F6.

The control box 22 and electrical equipment boxes 23, 23 are installed on one side of the fuel cell unit room, and the other side is covered with a cover 24, 24, with the cooling air passing between them. The air that has cooled the fuel cell unit room flows smoothly as it is straightened by the radiator fan 30d through the exhaust duct 10a, exhaust duct cover 10b, and exhaust louvers 10d. Since the cooling target of the fuel cell unit 30 is limited to a narrow area of the fuel cell stack 30a and radiator 30c, this allows for extremely efficient cooling.

REFERENCE SIGNS LIST 1 Front frame 2 Rear frame 3 Roof panel 4 Lower base, side door, splasher panel 9 Air intake 10 Exhaust 11 Air intake opening 12 Generated water outlet 13 Hydrogen supply port 14 Suspension hook 15 Suspension hook cover 16 Output terminal section 17 Operation panel 18 Operation switch 19 Emergency stop button 20 Upper base 21 Suspension bracket 22 Control box 23 Electrical equipment box 24 Cover 25 Power conditioner 26 Power conditioner control device 30 Fuel cell unit

Claims (4)

An internal cooling structure for a portable work machine, characterized in that semi-cylindrical frames are erected facing each other at both longitudinal ends of a housing that contains the work machine body so that the entire housing is oval-shaped when viewed from above, an air intake port is provided on one face of the frames and an exhaust port is provided on the other face of the frames, and cooling air is allowed to flow from the air intake port to the exhaust port along the curved surface inside the housing. The internal cooling structure of the portable work machine according to claim 1, characterized in that the intake port and the exhaust port are each provided with a plurality of parallel louvers, each of which has an arc-shaped tip that follows the outer periphery of the frame, is inclined obliquely downward from the inside to the outside of the housing, and is further rounded downward outward in a conical shape. The internal cooling structure of the portable work machine according to claim 1 or 2, characterized in that groove-shaped air guide members with a U-shaped cross section and open ends are laid down in parallel at a predetermined interval across the bottom of the housing, exhaust openings are provided on the sides of the middle parts of the air guide members facing each other, and air sucked in from the openings at both ends of the air guide members is introduced into the housing. The internal cooling structure of the portable work machine according to claim 3, characterized in that the inside of the housing is divided into two levels, an upper level and an lower level, a fuel cell unit is arranged as the work machine main body in the upper level, and a power conditioner is arranged in the lower level, and the air discharged from the exhaust opening of the air guide member cools the power conditioner arranged in the lower level of the housing and is then introduced into the upper level of the housing.

Images