JPH11148348A - Ventilation equipment of engine room - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the leakage of the noise generated in an engine room and make it easy to radiate the heat generated in the engine room to the outside. SOLUTION: The engine 13 in an engine room 12 is enclosed by an enclosure 11. An ejector 16 is provided in the upper face section 11a of the enclosure 11, on which the outlet section of the muffler 15 of an engine exhaust pipeline 14 is arranged, to such and discharge the heated air in the engine room 12 by using engine exhaust pressure for discharging the exhaust gas out of the enclosure 11. The ejector 16 is formed with a muffler exhaust outlet pipe 17, which is projected from the muffler 15, a tail pipe 18, which is projected from the enclosure 11 around the muffler exhaust outlet pipe 17, and a suction gap 19 formed between the muffler exhaust outlet pipe 17 and the tail pipe 18. Many slit-like suction ports 22 are provided in the lower face section 11b of the enclosure 11 located at a position opposite to the ejector 16 through an air flow passage 21 in the engine room 12. The intake ports 22 have a louver 23 for restraining the leakage of engine noise.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine room ventilation device provided in a construction machine or the like.

[0002]

2. Description of the Related Art As shown in FIG. 3, in a conventional design of a hydraulic excavator around an engine, a fan 5 directly connected to a rotating shaft 4 of the engine 3 together with an engine 3 is provided in an engine room 2 surrounded by an enclosure 1. The heat exchanger (radiator and oil cooler) 6 is arranged at an external position facing the fan 5 via the enclosure 1.

[0003] By the suction force of the fan 5, the cooling air passing through the external heat exchanger 6 is sucked into the engine room 2 through the opening of the enclosure 1.
In this structure, heat generated from the engine 3 and peripheral devices is transported by the wind supplied to the engine 3 from the controller 3 and released from the upper opening of the enclosure 1 to the outside.

On the opposite side of the heat exchanger 6 outside the enclosure 1, a hydraulic pump 7 driven by the engine 3 is provided.
Is arranged. The hydraulic pump 7 supplies hydraulic oil to various hydraulic actuators of a traveling system, a turning system, and a working machine system of the hydraulic shovel. The exhaust pipe 8 of the engine 3 is
The exhaust pipe of the muffler 9 is connected to a muffler 9 for silencing exhaust noise, and a tail pipe 10 projecting outside the enclosure 1 is directly connected to an exhaust outlet pipe of the muffler 9.

[0005]

In this conventional apparatus, a fan 5 in the engine room 2 surrounds the engine 3 in order to secure a flow path for cooling air sucked into the engine room 2 and discharged to the outside. The degree of sealing of the enclosure 1 had to be lowered.

For example, the hermetically sealed portion in the conventional enclosure 1 is only about two surfaces of a firewall located between the engine 3 and the hydraulic pump 7 and a cover plate located between the engine 3 and the control valve.

For this reason, the noise generated from the engine 3 easily leaks to the outside together with the heat released to the outside of the enclosure 1, and the noise level is deteriorated.

However, if the enclosure 1 is simply sealed to reduce the noise generated in the engine room 2 from leaking to the outside, the heat generated in the engine room 2 may be released to the outside. It became difficult, and the conventional technology around the engine could not solve both problems.

Further, the rotation speed of the fan 5 directly connected to the engine 3 is determined by the engine rotation speed and cannot be variably controlled even if the environmental temperature fluctuates, so that the water temperature of the heat exchanger (radiator and oil cooler) 6 There is also a problem that each cooling of the oil temperature cannot be appropriately performed according to the fluctuation of the environmental temperature.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has been made to reduce the noise generated in an engine room from leaking to the outside, and to easily release the heat generated in the engine room to the outside. The purpose of the present invention is to provide a ventilation system. It is another object of the present invention to enable the number of rotations of a fan that sends air to a heat exchanger to be appropriately variably controlled according to a change in environmental temperature or the like.

[0011]

According to the first aspect of the present invention, there is provided a partition wall formed in a hermetically sealed state, an engine room provided inside the partition wall, and an engine disposed in the engine room. And an ejector that is provided in a part of the partition body and sucks heated air in the engine room using the engine exhaust pressure discharged to the outside of the partition body and discharges the heated air to the outside, and the ejector is opposed to the ejector via an air passage in the engine room. And a suction port provided in a partition located on the side.

[0013] The partition formed in a sealed shape reduces the noise generated in the engine compartment from leaking to the outside, and at the same time, a pump action of the ejector utilizing the engine exhaust pressure discharged to the outside of the partition. Thereby, the heated air in the engine room is sucked, and the heat generated in the engine room is forcibly released to the outside. In addition, the position of the intake port provided on the partition wall opposite to the ejector via the air passage in the engine room moves the air sucked into the engine room so as to cool the room while hitting each device in the engine room. Secure cooling air passages.

According to a second aspect of the present invention, in the engine room ventilator according to the first aspect, at least a heat exchanger for cooling the engine disposed outside the partition body and heat exchange outside the partition body. A fan provided to face the vessel and a fan driving motor arranged outside the partition.

A heat exchanger, a fan, and a motor for driving the fan are provided outside the partition body, and the heat exchange air path is completely separated from the air path in the engine room, thereby increasing the degree of sealing of the partition body. At the same time, the rotation speed of the fan that sends the cooling air to the heat exchanger is appropriately variably controlled according to the fluctuation of the environmental temperature without being restricted by the engine rotation speed.

According to a third aspect of the present invention, in the engine room ventilation device according to the first or second aspect, the ejector includes an inner pipe protruding from a muffler in an engine exhaust pipe;
It has an outer tube protruding from the partition wall longer than the inner tube around the inner tube, and a suction gap formed between the inner tube and the outer tube for sucking air in the engine room.

The simple double pipe structure of the inner pipe protruding from the silencer and the outer pipe protruding from the partition body,
An ejector utilizing the engine exhaust pressure is formed, and the air in the engine compartment is forcibly released to the outside together with heat by a pump action based on a negative pressure generated in a suction gap of the ejector.

According to a fourth aspect of the present invention, the intake port in the engine room ventilation system according to any one of the first to third aspects has a noise suppressing means for suppressing leakage of engine noise to the outside. is there.

The noise suppression means suppresses the possibility that the engine noise leaks from the intake port to the outside.

According to a fifth aspect of the present invention, in the engine room ventilation device according to any one of the second to fourth aspects, the intake port is provided on a surface of the partition wall that is different from a surface portion that receives air from the fan. It is a thing.

Since the air blown from the fan does not enter the engine room through the air inlet, the air flow from the air inlet to the ejector in the engine room is not disturbed by the air blown from the fan. Dissipates heat.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows a ventilation system for an engine room according to the present invention. Reference numeral 11 denotes an enclosure as a partition formed in a sealed shape.
All six surfaces are covered by a cover plate. An engine room 12 is formed inside the enclosure 11, and an engine 13 is arranged in the engine room 12. This engine 13 is the same as a conventional diesel engine or the like except for the exhaust system, and therefore its illustration and structural description are omitted.

In the exhaust system of the engine 13, a muffler (hereinafter, referred to as “muffler”) 15 is provided in the engine exhaust line 14, and an enclosure in which an outlet of the muffler 15 is disposed. An ejector 16 is provided on a part of the upper surface 11a of the engine 11 for sucking heated air in the engine room 12 using the engine exhaust pressure discharged to the outside of the enclosure 11 and discharging the heated air to the outside.

The ejector 16 includes a muffler exhaust outlet pipe 17 as an inner pipe protruding from the muffler 15, and an outer pipe protruding from the enclosure 11 around the muffler exhaust outlet pipe 17 longer than the muffler exhaust outlet pipe 17. Tail pipe as
18 and a suction gap 19 formed between the muffler exhaust outlet pipe 17 and the tail pipe 18 for sucking the air in the engine chamber 12.

The ejector 16 is an air passage 21 in the engine room.
The lower surface 11b of the enclosure 11 located on the opposite side via
Are provided with a number of slit-shaped intake ports 22.

Each of these intake ports 22 has a louver 23 as noise suppression means for suppressing leakage of engine noise to the outside of the enclosure. These louvers 23 are formed by cutting and raising from the respective intake ports 22.

Further, as a noise suppressing means, a sound absorbing effect is provided at an intake port (not shown) formed in a box shape, and engine noise and intake noise leaking from the intake port to the outside of the enclosure 11 are suppressed. You may do it.

On the other hand, outside the enclosure 11, FIG.
1, a hydraulic pump 24 driven by the engine 13 is continuously arranged on the right side, and a heat exchanger 25 is separately arranged on the left side in FIG. The heat exchanger 25 is a radiator for engine cooling water and an oil cooler for oil temperature cooling of a hydraulic circuit, but are shown integrally in the drawing.

A fan 26 provided facing the heat exchanger 25 and a motor 27 for driving the fan 26
Are also arranged outside the enclosure 11.

The motor 27 is a hydraulic motor that is driven to rotate by hydraulic oil supplied from the hydraulic pump 24 or an electric motor that is driven to rotate by a vehicle-mounted battery (not shown). To drive the fan 26. In other words, regardless of the rotation speed of the engine 13, by controlling the rotation speed of the motor 27 in accordance with the ambient environmental temperature, the amount of air blown by the fan 26 can be arbitrarily controlled, and the water temperature and oil temperature can be appropriately cooled. it can.

The intake port 22 is provided on a lower surface portion 11b of the enclosure 11 which is different from the side surface portion 11c which receives the air from the fan 26, and is located at a position which is not affected by the air from the fan 26.

Even if the blown air from the fan 26 goes around the lower surface 11b of the enclosure 11, the louvers 23
Is projected in the same direction as the air flow from the fan 26, the air flow from the fan 26 does not directly affect the air inlet 22.

The support structures of the engine 13, the heat exchanger 25, the motor 27 and the like are not special, so that their support structures are not shown or described.

As shown in FIG.
Between the cover plates 28 of the respective surfaces, a cushion-type sealing material 29 is interposed, which prevents noise from leaking out of the engine room 12 to the outside, and also prevents wind from entering and exiting. Vibration propagation is prevented.

The sealing member 29 includes a fitting portion 29a having a U-shaped cross section fitted on one cover plate 28 and a contact portion 29b having a circular hollow cross section abutting on the other cover plate 28. Due to the elasticity of the contact portion 29b, each cover plate 28
Keep the tightness between them. Note that members for connecting the cover plates 28 are omitted.

As described above, in order to prevent engine noise from being emitted to the outside, the enclosure 11 surrounding the engine 13
In order to release the temperature inside the engine chamber 12 to the outside, the fan 26 is separated from the engine 13, taken out of the engine chamber 12, and driven by hydraulic pressure or electric power. By using the exhaust pressure of the muffler 15, heat is radiated from the suction gap 19 between the muffler exhaust outlet pipe 17 and the tail pipe 18. Since the opening area of the suction gap 19 is small, noise of the engine 13 hardly leaks from the suction gap 19 to the outside.

In consideration of the fact that each device in the engine compartment 12 can supply an air volume not exceeding the allowable limit temperature, the intake area 22 and the opening of the intake port 22 into the engine compartment 12 are controlled. Set the position, etc.

Next, the operation of the illustrated embodiment will be described.

The enclosure 11 formed in a sealed shape reduces the noise generated in the engine room 12 from leaking to the outside, and the pump of the ejector 16 uses the engine exhaust pressure discharged outside the enclosure 11. By the action, the heated air in the engine room 12 is sucked, and the heat generated in the engine room 12 is forcibly released to the outside together with the air.

The ejector 16 has a simple double-pipe structure including a muffler exhaust outlet pipe 17 protruding from the muffler 15 and a tail pipe 18 protruding from the enclosure 11. A negative pressure is generated around the high-speed engine exhaust flow ejected into the inside, and the suction gap 19 also has a negative pressure, so that the pumping action based on this negative pressure sucks the air in the engine room 12 together with heat to the outside. Release forcefully.

At this time, the wind sucked into the engine room 12 is controlled by the position of the intake port 22 provided in the enclosure 11 on the opposite side from the ejector 16 via the air passage 21 in the engine room. A cooling air passage that moves so as to cool the room while hitting is secured.

On the other hand, the heat exchanger 25, the fan 26, and the motor 27 for driving the fan are provided outside the enclosure 11, and the heat exchange air passage 31 passing through the heat exchanger 25 is completely separated from the engine room air passage 21. This makes it possible to increase the degree of sealing of the enclosure 11 and prevent the engine noise from being emitted outside.

In particular, the side surface 11c receiving the air from the fan 26 in the enclosure 11 is different from the lower surface 11b provided with the air inlet 22, so that the air from the fan 26 is
Since it does not enter the engine room 12 from the inlet 22, the intake port 22
The air passage 21 in the engine room from the
The heat can be dissipated as planned without being disturbed by the air flow from 26.

Further, by controlling the number of rotations of the motor 27, the number of rotations of the fan 26 for sucking the cooling air into the heat exchanger 25 can be freely controlled, without being restricted by the number of rotations of the engine as in the prior art. In addition, the water temperature of the radiator and the oil temperature of the oil cooler can be appropriately variably controlled according to the fluctuation of the environmental temperature.

As described above, the heat radiation from the inside of the engine chamber 12 by the ejector 16 utilizing the exhaust pressure from the muffler 15 causes the suction gap 19 having an extremely small opening area between the muffler exhaust outlet pipe 17 and the tail pipe 18. Therefore, it is possible to emit only heat without emitting noise in the engine room 12 to the outside.

In order to prevent the noise in the engine room 12 from being emitted to the outside, the enclosure 11 around the engine also needs to substantially completely surround the six surfaces around the engine 13. As described above, the connection between the cover plate 28 and the cushion-type sealing material 29 is frequently used, and the point that the louver type or the box type is effective so that the engine noise does not directly come out from the intake port 22 is as described above. It is.

Further, the position of the intake port 22 is designed so that each device in the engine room 12 does not exceed the permissible limit temperature, so that the outside air hits each device and is directed to the muffler 15. .

In particular, the air from the fan 26 is
When the air enters the interior, the air passage 21 in the engine room is disturbed and the planned heat release cannot be performed.
Has a complete shielding structure.

The scope of application of the present invention is not limited to the engine room of a hydraulic shovel, but may be applied to other construction machines such as a loader and a bulldozer, and also to an engine room of another vehicle other than the construction machine. It is possible to Further, the present invention is applicable not only to diesel engines but also to gasoline engines.

[0050]

According to the first aspect of the present invention, the partition wall formed in a sealed shape can reduce the noise generated in the engine compartment from leaking to the outside, and can maintain the surrounding environment in a good condition. By the pumping action of the ejector that makes effective use of the engine exhaust pressure discharged to the outside of the partition,
The heated air in the engine room can be forcibly sucked, and only the heat generated in the engine room can be efficiently released to the outside. In addition, with the ejector, the air sucked into the engine room moves while hitting each part in the engine room by the intake port provided in the partition body located on the opposite side via the air passage in the engine room, and the parts in the engine room are moved. A cooling air path that can be cooled effectively can be secured.

According to the second aspect of the present invention, a heat exchanger,
A fan and a motor for driving the fan are provided outside the partition body, and the heat exchange air passage is completely separated from the air passage in the engine room. The rotation speed of the fan that sends the cooling air to the exchanger can be variably controlled appropriately in accordance with environmental temperature fluctuations without being restricted by the engine rotation speed.

According to the third aspect of the present invention, the ejector utilizing the engine exhaust pressure can be easily provided by the simple double pipe structure of the inner pipe protruding from the muffler and the outer pipe protruding from the partition. In addition, the pump action of the ejector allows the air in the engine room to be efficiently released to the outside together with heat, and the external leakage of engine noise is effectively prevented by the narrow suction gap formed between the inner pipe and the outer pipe. Can be suppressed.

According to the fourth aspect of the present invention, the possibility that engine noise leaks from the intake port to the outside can be suppressed by the noise suppressing means, and the surrounding environment can be kept better.

According to the fifth aspect of the present invention, since the air blown from the fan does not enter the engine room through the air inlet, the air flow from the air inlet to the ejector in the engine room is disturbed by the air blown from the fan. The heat radiation from the engine room can be secured as planned.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of an engine room ventilation device according to the present invention.

FIG. 2 is a cross-sectional view showing a seal structure in a partition body of the ventilation device.

FIG. 3 is a schematic view showing a conventional engine room ventilation device.

[Explanation of symbols]

 11 Enclosure as a partition 12 Engine room 13 Engine 14 Engine exhaust line 15 Silencer (muffler) 16 Ejector 17 Muffler exhaust outlet tube as inner tube 18 Tail pipe as outer tube 19 Suction gap 21 Engine room air passage 22 Intake Mouth 23 Louver as noise suppression means 25 Heat exchanger (radiator) 26 Fan 27 Motor

Claims (5)

[Claims] 1. A partition wall formed in a sealed shape, an engine room provided inside the partition body, an engine disposed in the engine room, and an outside of the partition wall provided in a part of the partition body An ejector that sucks heated air in the engine room using the exhaust pressure of the engine discharged to the outside and discharges the heated air to the outside; and the ejector includes an intake port provided in a partition wall located on the opposite side via an air passage in the engine room. An engine room ventilation device, comprising: 2. A heat exchanger for cooling at least the engine disposed outside the partition, a fan provided outside the partition and facing the heat exchanger, and a fan disposed outside the partition. The engine room ventilation device according to claim 1, further comprising a motor for driving a fan. 3. An ejector comprising: an inner pipe protruding from a muffler in an engine exhaust pipe; an outer pipe protruding from the partition body longer than the inner pipe around the inner pipe; and an inner pipe and an outer pipe. 3. The engine room ventilation system according to claim 1, further comprising: a suction gap formed between the suction holes and a suction gap for sucking air in the engine room. 4. The engine room ventilation device according to claim 1, wherein the intake port has a noise suppression unit that suppresses leakage of engine noise to the outside. 5. The engine room ventilation device according to claim 2, wherein the intake port is provided on a surface of the partition wall that is different from a surface of the partition body that receives air from the fan.