JP2001355445A - Cooling structure for engine working machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To cool engine lubricating oil in an engine working machine with simple structure. SOLUTION: In the engine working machine, an engine 3, a working machine body 4 driven by the engine, and an air-cooled heat exchanger 9 facing a cooling fan 8 of the engine, are arranged in a soundproof box 1, and a shroud 16 connected to the heat exchanger 9, surrounding the circumferential direction of the cooling fan is provided between the cooling fan 8 and the heat exchanger 9. An air guide duct 25 having an opening 27 with an appropriate space to the external wall of an oil of the engine 3 is connected to the shroud 16, and a space between the opening 27 and the shroud 16 is made a cooling air guide passage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling structure of an engine working machine for effectively cooling an engine oil pan in a soundproof engine working machine.

[0002]

2. Description of the Related Art As shown in FIG. 5, a conventional engine working machine includes an engine 102 and a working machine main body 103 such as a compressor or a generator driven by the engine in a soundproof box 101.
In addition to the heat exchanger 104, various devices required for operation are arranged, and the side wall 1 of the frame 105 supporting the soundproof box 101 is provided.
06 or a bottom wall 107 is provided with an inlet 108 for outside air, and a cooling fan 109 is provided in front of the engine 102 so that the outside air passing through the soundproof box 101 cools the heat exchanger 104 by driving the cooling fan. It has become.

A shroud 110 surrounding the cooling fan 109 and connected to the heat exchanger 104 is arranged in the circumferential direction of the cooling fan 109, and the cooling air blown from the cooling fan passes through the heat exchanger 104. At the same time, a cooling air guide path 111 is formed at one end of the soundproof box 101 so that the warm air that has cooled the inside of the soundproof box is discharged to the outside.

[0004] An oil pan 113 for storing lubricating oil for lubricating various parts in the engine is mounted on the lower bottom 112 of the engine 102.

[0005]

The components of a soundproof engine working machine (for example, a generator or a compressor) are generally cooled by the outside air drawn into the soundproof box by an engine cooling fan. Oil pan 113
Since the cooling air was located in the lower part of the soundproof box 101, it was blocked by the various devices in the machine, and the cooling air did not pass through effectively. Therefore, the lubricating oil temperature in the oil pan was easily increased.

Further, since the lubricating oil of the engine lubricates the overheated parts of the engine and stores them in the oil pan below the lubricating oil, it receives heat from the sliding parts in the engine in the process of lubricating the parts. It is hot.

When the lubricating oil temperature is higher than a predetermined value, oil film breakage occurs in each of the sliding and rotating parts in the engine, causing fatal problems such as abnormal wear and seizure. . In addition, if the lubricating oil is operated for a long time with the lubricating oil kept at a high temperature, deterioration of the lubricating oil proceeds, and there is a problem that the life of the lubricating oil is shortened. Therefore, the lubricating oil must be constantly circulated at an appropriate temperature, and for that purpose, the oil pan as well as the lubricating oil needs to have a sufficient cooling structure.

As a soundproof type working machine of this kind, Japanese Utility Model Laid-Open No.
A soundproof engine working machine disclosed in 92037 is known.

In this engine working machine, a duct-shaped intake path is formed in the bottom wall of the soundproof box and is isolated from the internal space, and an opening is formed in a portion of the engine facing the oil pan, so that the outside air sucked from the outside can be used. Although the oil pan of the engine is cooled, the air intake passage is close to the ground, and the air filter attached to each device housed in the soundproof box by sucking in the outside air and sucking the dust and dirt on the ground. In addition to clogging the radiator and the radiator, there is a problem that the inside of the soundproof box is contaminated with dust.

As another countermeasure, an oil cooler (water-cooled or air-cooled) for cooling the lubricating oil of the engine is also provided. In such a case, a space for mounting the oil cooler is required. Therefore, there is a problem that the soundproof box itself is large and the weight is increased, and the cost is increased as a whole.

Accordingly, the present invention solves the above-mentioned problems and provides an engine working machine capable of effectively cooling engine oil without providing an oil cooler for the engine or a suction port for outside air at the bottom of the soundproof box. A cooling structure is provided.

[0012]

In order to achieve the above object, according to the present invention, an engine 3, a work machine main body 4 driven by the engine, and a cooling fan 8 of the engine 1 are provided in a soundproof box 1. In the engine working machine in which the air-cooled heat exchanger 9 is arranged, the space between the cooling fan 8 and the heat exchanger 9 surrounds the circumferential direction of the cooling fan 8 and is connected to the heat exchanger 9. A shroud 16 is provided, and an air guide duct 25 having an opening 27 is connected to the shroud 16 at an appropriate interval between the shroud 16 and an outer wall of an oil pan 26 of the engine 1, and cooling air flows between the opening 27 and the shroud 16. The air guide path 28 is provided (claim 1).

With the above configuration, the lubricating oil in the oil pan 26 can be indirectly cooled by the part of the outside air flowing into the soundproof box 1 through the outer wall of the engine oil pan 26, and the outside air intake 7 is also removed from the ground surface. Since the soundproof box 1 is located on the outer wall of the remote soundproof box 1, the inside of the soundproof box 1 is not contaminated with dust.

Furthermore, the suction port of the air guide duct 25 connected to the shroud 16 can be opened at the front end of the shroud 16 and near the primary side of the cooling fan 8 (claim 2). The heat exchanger 9 includes two heat exchangers 10 and 11 arranged in parallel, and surrounds the cooling fan 8 in the circumferential direction between the cooling fan 8 and the heat exchanger 9. shroud 16 which connects to the heat exchanger 9 Te
And a shroud peripheral wall 19 near one of the sides of the heat exchanger 9 is provided with an oil pan 26 of the engine.
An air guide duct 25 having an opening 27 may be connected to the outer wall at an appropriate interval, and a space between the opening 27 and the shroud 16 may be used as a cooling air guide path. By doing so, the opening position of the inlet of the air guide duct 25 can be selected in accordance with the heat radiation capacity of each of the heat exchangers arranged in parallel, and the heat radiation balance of the heat exchangers can be maintained.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIG.

The engine 3 is mounted on the frame 2 of the soundproof box 1.
The work machine main body (compressor) 4 driven by the engine 3 is directly connected to the engine 3, and a lower bottom portion of the frame is separated from the outside by a bottom wall 2a.

A cooling air intake 7 is opened in the side wall 5 (left side in the figure) of the soundproof box 1 in the vicinity of the work machine body 4, so that noise in the soundproof box 1 does not leak out of the machine through the opening. Is provided with the suction duct 6 as described above.

On the other hand, an air-cooled heat exchanger 9 is disposed in front of the engine 3 (right side in the figure) so as to face the cooling fan 8, and the heat exchanger 9 is used for cooling engine cooling water. A radiator 10 and an oil cooler 11 for cooling the lubricating oil of the working machine body (compressor) 4 are arranged in series.

On one side of the soundproof box 1, a partition plate 12 is provided in front of the heat exchanger 9 (right side in the figure).
An exhaust chamber 13 that forms an exhaust path for the cooling air A exhausted by the exhaust air is provided, and an exhaust port 15 that communicates with the outside is provided on an upper wall 14 thereof.

Further, between the cooling fan 8 and the heat exchanger 9, a shroud 16 surrounding the cooling fan in the circumferential direction is provided.
One of which is the heat exchanger 9 or the partition plate 12
Blower chamber 1 for cooling air blown from cooling fan 8
7 are formed.

Therefore, the flow of air between the inside of the soundproof box 1 and the air discharge chamber 13 is shut off with the partition plate 12 interposed therebetween, and the flow of air is performed only through the air passage 18 of the heat exchanger 9. Is configured.

An air guide duct 25 connected to the peripheral wall 19 of the shroud 16 via a space 20 in the frame 2 is provided, and one of the air guide ducts 25 communicates with the air blow chamber 17 through an inflow port 29. The other end of the air guide duct surrounds the periphery of the oil pan 26 of the engine and forms an opening 27 at an appropriate distance from the outer wall of the oil pan. Thus, the air guide passage 28 formed in the air guide duct 25 forms a cooling air flow passage communicating from the air supply chamber 17 of the shroud 16 to the opening 27 around the oil pan 26 of the engine.

The air guide duct 25 may be formed as an independent individual duct, or the inside of the frame 2 may be partitioned by a partition plate to form an air guide passage. May be appropriately determined according to the conditions.

Next, the operation will be described.

When the engine 3 starts and the work machine body 4 and the cooling fan 8 are driven, outside air is introduced into the soundproof box 1 from the air inlet 7. Then, the outside air passes between devices (not shown) in the soundproof box so as to send out the heated air in the soundproof box 1 by suction of the cooling fan 8.
After cooling the inside of the machine, the heat exchanger is cooled while passing through the air passage 18 of the heat exchanger 9. Thereafter, the air is discharged from the exhaust chamber 13 to the atmosphere through an exhaust port 15 provided thereabove.

The pressure distribution from the inside of the soundproof box 1 to the air supply chamber 17 and the air discharge chamber 13 of the shroud in this process and its operation will be described with reference to FIG.

That is, the primary side (left side in the figure) of the cooling fan 8
The inside (P) of the soundproof box 1 becomes a weak negative pressure δ due to the driving of the cooling fan 8, and outside air is sucked into the soundproof box by the negative pressure. In this negative pressure state, the entire pressure on the primary side of the cooling fan 8 is substantially the same.

On the other hand, the inside (Q) of the blowing chamber 17 of the shroud on the exhaust side, that is, the secondary side of the cooling fan 8 is
The pressure becomes positive pressure, that is, positive pressure α due to the wind pressure discharged from the air and the flow resistance when passing through the heat exchanger 9. further,
In the exhaust chamber 13 (R) on the secondary side of the heat exchanger 9, the upper exhaust port 15 communicates with the atmosphere, so that the heat exchanger 9
Is slightly positive due to the wind pressure exhausted from the air.

As is clear from the above, the pressure distribution in the soundproof box 1 is highest in the blower chamber 17 (Q). Therefore, part of the cooling air in the blower chamber 17 is in the soundproof box (P).
Flows through the air guide path 28 of the air guide duct 25 due to the pressure difference from the pressure δ near the oil pan 26 and diffuses into the soundproof box 1 from the opening 27. In the process, the internal engine lubricating oil is indirectly cooled while cooling the outer wall of the oil pan 26.

Then, the cooling air diffused in the soundproof box 1 is sent again to the heat exchanger 9 by the cooling fan 8 together with the outside air passing through the soundproof box, and then discharged outside from the air outlet 15. .

Since the present invention is configured as described above, the engine lubricating oil can be effectively cooled without providing an oil cooler for the engine, so that the structure inside the soundproof box is simple and the whole is small and inexpensive. Engine working machine.

Further, unlike the related art, there is no need to provide an inlet for taking in outside air on the side wall or the bottom wall of the frame, so that there is no danger of dust entering from the ground below the working machine, and therefore, each device in the soundproof box is not required. For example, the engine 3 and the working machine body 4
The air filter (not shown) and the heat exchanger 9 are not clogged.

Further, since the bottom wall of the soundproof box 1 is also shielded from the outside, the explosion sound and mechanical sound in the engine that pass through the oil pan of the engine do not leak out of the machine.

FIG. 3 shows a second embodiment of the present invention, in which the front end 40 of the shroud 16 and the vicinity 41 of the primary side of the cooling fan 8 are shown.
The suction port 42 of the air guide duct 25a is opened, and the end of the air guide path 28 is provided through an opening 27 which surrounds the periphery of the oil pan 26 of the engine and is appropriately spaced from the outer wall of the oil pan. And communicates with the inside of the soundproof box 1.

The second embodiment is constructed as described above. The operation of the cooling fan 8 is such that the vicinity 41 of the primary side of the cooling fan is directed from the inside of the soundproof box 1 toward the heat exchanger 9. A negative pressure δ1 is stronger than that in the soundproof box 1 due to the airflow sucked and blown by the airflow.
A part of the outside air passing through the inside of the air guide passage 2 is bypassed into the opening 27 of the air guide duct near the engine oil pan 26 and flows into the air guide passage 2.
The air is sucked from a suction port 42 opened near the primary side 41 of the cooling fan 8 from the cooling fan 8 and is sent to the heat exchanger 9 together with the outside air passing through the soundproof box 1.

Therefore, the outer wall of the oil pan 26 is cooled by a part of the outside air that bypasses the inside of the soundproof box 1, thereby also cooling the lubricating oil in the oil pan.

FIG. 4 shows a third embodiment of the present invention, in which two heat exchangers constituting a heat exchanger, a radiator for an engine and an oil cooler for a working machine body (compressor) are arranged in parallel. The same members as those described in the first embodiment will be described using the same names and the same reference numerals.

A heat exchanger 9 is disposed in front of a cooling fan 8 of the engine, and the heat exchanger 9 has a radiator 10 on one side wall 1a side of the soundproof box 1 in plan view.
Oil coolers 11 are arranged in parallel on the other side wall 1b side. On one side of the soundproof box 1, a partition plate 12 a is provided in front of the heat exchanger 9 (right side in the figure), and cooling air flows between the inside of the soundproof box 1 and the blower chamber 13 across the partition plate. Is blocked.

A shroud 16a is connected between the cooling fan 8 and the heat exchanger 9a, that is, the radiator 10 and the oil cooler 11, and one of them is connected to the heat exchanger 9a or the partition plate 12a. ing.

Further, an inlet 29 of an air guide duct 25 connected through a space 20 of the frame 2 is opened in the shroud peripheral wall 19 near the oil cooler 11 side of the heat exchanger 9a, that is, near the side wall 1b of the soundproof box. The other end is open to the inside of the soundproof box from the opening 27 near the engine oil pan in the same manner as described in the first embodiment.

The inflow port 29 of the air duct is biased toward one of the radiator 10 and the oil cooler 11 arranged on the side wall 1a of the soundproof box or on the opposite side wall 1b. I have.

This selection is preferably provided on the side of the radiator 10 or the oil cooler 11 having a sufficient amount of heat exchange, because the cooling air passing through the heat exchanger 9a via the air blowing chamber 17 of the shroud 16 is preferably used. This is because a part of the wind flows from the inflow port 29 of the wind guide duct 25 to the oil pan side, so that a sufficient amount of heat exchange is required. In other words, if there is a margin of heat exchange on the radiator 10 side with respect to the oil cooler 11, the shroud peripheral wall 1 closer to the radiator side
9 may be provided.

As described above, the outside air flowing into the soundproof box 1 from the air inlet 7 by the driving of the cooling fan 8 passes through the heat exchanger 9 a by the cooling fan 8. The pressure (Q in FIG. 2) in the blow chamber 17 of the shroud on the wind side, ie, the secondary side,
Because of the positive pressure (α in FIG. 2) due to the wind pressure blown from the air and the flow resistance when passing through the heat exchanger 9a, the pressure difference is derived from the negative pressure (δ in FIG. 2) near the oil pan 26. Cooling air flowing into the air duct 28 of the wind duct diffuses into the soundproof box 1 from the opening 27 near the oil pan 26.

Therefore, as described in the first embodiment, the cooling air that has passed through the air guide passage 28 cools the outer wall of the oil pan in the process of passing near the oil pan 26 and removes the internal engine lubricating oil. Cooling.

As a result, the operation described in the first embodiment
In addition to the effects, it becomes easier to balance the temperature of the engine cooling water, the temperature of the engine lubricating oil, and the temperature of the lubricating oil of the working machine body. In addition, since it is not necessary to significantly increase the cooling performance of the radiator 10 and the oil cooler 11, the outer dimensions of the soundproof box housing the heat exchanger can be reduced.

[0046]

As described above, the present invention provides a shroud which surrounds the cooling fan of the engine working machine and connects to the heat exchanger, and the shroud is provided between the shroud and the outer wall of the oil pan of the engine. By connecting an air guide duct having an opening at an appropriate interval to the opening and the inside of the shroud as a cooling air guide path, a part of the outside air flowing into the soundproof box can reduce the oil pan outer wall of the engine. This cools the internal lubricating oil through the lubricating oil, thereby cooling and lubricating each sliding portion in the engine with the lubricating oil at an appropriate temperature. Also,
Since the outside air intake is also provided on the outer wall of the soundproof box remote from the ground surface, the inside of the soundproof box is not contaminated with dust, and clogging of the air filters and heat exchangers of each device can be prevented.

Further, since there is no need to provide an oil cooler for cooling the engine lubricating oil, it is possible to provide a small and inexpensive engine working machine as a whole.

In the case where two heat exchangers are arranged in parallel, by selecting the opening position of the inlet of the air guide duct in accordance with the heat radiation capacity of each heat exchanger, the heat radiation amount of the heat exchanger can be reduced. You can keep the balance.

[Brief description of the drawings]

FIG. 1 is a schematic layout diagram of an engine working machine of the present invention.

FIG. 2 is a pressure distribution diagram in a soundproof box.

FIG. 3 is a schematic layout diagram in a second embodiment.

FIG. 4 is a plan view of the inside of a soundproof box according to a third embodiment.

FIG. 5 is a schematic view of a conventional engine working machine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Soundproof box 2 Frame 3 Engine 4 Work machine main body 6 Intake duct 7 Intake 8 Cooling fan 9 Heat exchanger 10 Radiator 11 Oil cooler 12 Partition plate 13 Exhaust chamber 15 Exhaust port 16 Shroud 17 Ventilation chamber 25 Air guide duct 26 Oil Bread 27 opening 28 air duct

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) F02B 67/00 F02B 67/00 G 77/13 77/13 L

Claims (3)

[Claims] An engine working machine in which an engine, a working machine main body driven by the engine, and an air-cooled heat exchanger are arranged opposite to a cooling fan of the engine in a soundproof box. A shroud surrounding the cooling fan and connected to the heat exchanger is provided between the heat exchanger and the shroud, and the shroud has an opening at an appropriate interval between the shroud and an outer wall of an oil pan of the engine. A cooling structure for an engine working machine, wherein an air guide duct is connected, and a space between the opening and the shroud is used as a cooling air guide path. 2. The engine working machine according to claim 1, wherein a suction port of the air guide duct connected to the shroud opens at a front end of the shroud and near a primary side of the cooling fan. Cooling structure. 3. The heat exchanger according to claim 1, wherein two heat exchangers are arranged in parallel, and between the cooling fan and the heat exchanger, the heat exchanger surrounds the cooling fan in a circumferential direction. A shroud connected to the heat exchanger is provided, and a shroud peripheral wall near one of the sides of the heat exchanger is connected to a wind guide duct having an opening at an appropriate interval between the shroud peripheral wall and an oil pan outer wall of the engine, The cooling structure for an engine working machine according to claim 1, wherein a space between the opening and the shroud is a wind guide path for cooling air.