JP2000265837A - Engine exhaust device of construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely diffuse the exhaust gas without breaking an exhaust pipe, and to facilitate the attachment/detachment of an engine exhaust device by mounting a diffuser on an exterior. SOLUTION: Exhaust gas from an engine is discharged outside through a muffler mounted on one side of the engine, and an exhaust pipe 62 which is mounted on the muffler and is capable of discharging the exhaust gas outside. A diffuser 3 capable of diffusing the exhaust gas of the engine and discharging it outside is mounted in an attachable/detachable manner on a diffuser fitting surface of an armor 2. The diffuser 3 is provided with a plurality of stays 3a to be connected to a diffuser fitting surface 2a by bolts 4 and a plate-shaped collision plate 3b supported by a plurality of stays 3a. By mounting the diffuser 3 on the armor 2 side, the fitting strength is increased, and the service life of the exhaust pipe 62 can be improved since the exhaust pipe 62 is not damaged even if the exhaust pipe is attached/detached for maintenance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine exhaust device for a construction machine such as a hydraulic shovel having a diffusion device capable of diffusing exhaust gas discharged from an engine.

[0002]

2. Description of the Related Art A conventional engine exhaust device for a construction machine will be described below in detail with reference to the drawings. FIG. 6 is a plan view showing a general hydraulic excavator. FIG. 7 is a detailed view of a main part showing an engine room of the hydraulic shovel shown in FIG. In the drawing, reference numeral 50 denotes a hydraulic excavator. The hydraulic excavator 50 includes a lower traveling body 51 that can travel freely, an upper revolving body 52 that is rotatably mounted on the lower traveling body 51, At the front, an attachment 53 is provided that is rotatable in the front-rear and left-right directions. An operator cab 52a is provided above the upper revolving superstructure. An engine room 54 for housing an engine 60 is disposed at the rear of the upper swing body 52. An exhaust pipe hole 5 through which an exhaust port 62a of an exhaust pipe 62, which will be described later, protrudes to the outside,
4b is provided.

The engine 60 is provided with a muffler 61 and an exhaust pipe 62 attached to the muffler 61 and having an exhaust port 62a capable of discharging exhaust gas from the engine 60 to the outside. The exhaust gas of the engine 60 is directly discharged to the outside from an exhaust port 62a through a muffler 61 and an exhaust pipe 62 attached to the muffler 61.

[0004] As an example of a conventional device for diffusing exhaust gas directly discharged from the exhaust port 62a to the outside, there is a diffusion device shown in FIG. FIG.
It is a principal part enlarged view which shows the conventional diffusion apparatus shown in No. 081. 6 and 7 are denoted by the same reference numerals. An exhaust pipe hole 54b is formed in a part of the exterior 54a. This exhaust pipe hole 54b has an exhaust port 6
A part of the exhaust pipe 62 having 2a is fitted. A diffuser 63 capable of diffusing the exhaust gas discharged from the exhaust port 62a is detachably attached to the exhaust pipe 62 in a state of protruding from the exterior 54a. This diffusion device 63
The cylindrical portion 67 has a plurality of slits 64 at one end, and a collision plate 65 attached to the other end of the cylindrical portion 67 via a plurality of stays 66. The collision plate 6
5 is formed of a punching metal having a plurality of small holes. When attaching the diffusion device 63 to the exhaust pipe 62, one end (the slit 64 side) of the cylindrical portion 67 is fitted into the exhaust pipe 62a. Since the diameter of the cylindrical portion 67 is changed by the slit 64, the fitting can be performed. The exhaust gas passing through the exhaust pipe 62 is discharged from the exhaust port 62 and collides with the collision plate 65 of the diffusion device 63. The exhaust gas that has collided is discharged to the outside from the small holes of the collision plate 65 and also to the outside from between the plurality of stays 66.

[0005]

In a construction machine such as a small hydraulic excavator shown in FIG. 6, an operator's cab and an engine room are arranged very close to each other. For this reason, it is not common to provide an exhaust port for discharging exhaust gas from the engine disposed in the engine room to the upper part of the engine room because of a problem that the exhaust gas flows into the operation room. To this end, as shown in FIG. 7, an exhaust pipe hole is generally provided in a part of an exterior provided on the rear surface of the upper revolving superstructure.
According to this, since the exhaust port is arranged at a position away from the cab, there is no need to worry about exhaust gas flowing into the cab.
On the other hand, in a configuration in which the exhaust port is arranged on the outer surface of the rear surface of the upper revolving structure, since the high-temperature exhaust gas is directly discharged from the exhaust port, the planting is withered or the exhaust gas is blown to a nearby pedestrian. Had environmental problems.

For this reason, there has conventionally been provided a structure in which a diffusion device for diffusing exhaust gas is attached to an exhaust port as shown in FIG. According to this, the high-temperature exhaust gas discharged from the exhaust port comes into contact with the diffusion device and is diffused, so that there is no environmental problem such as exhausting the planting or blowing the exhaust gas to a nearby pedestrian. However, since the diffusion device shown in FIG. 7 has a configuration in which the diameter of the cylindrical portion is changed by the slit and fitted into the exhaust pipe, the diffusion device may come off depending on an error between the diameter of the cylindrical portion and the diameter of the exhaust pipe. There was a problem that the exhaust pipe side was damaged easily and the diffusion device was difficult to attach. In addition, mounting the diffusion device on the exhaust pipe in the exhaust pipe hole requires the insertion of the diffusion device into a small gap between the exhaust pipe and the exhaust pipe hole, so that the assembly cannot be easily performed. Was causing the decline.

The present invention has been made in view of such circumstances, and an engine exhaust of a construction machine equipped with a diffusion device that can surely diffuse exhaust gas without damaging an exhaust pipe and that can be easily attached and detached. It is intended to provide a device.

[0008]

According to a first aspect of the present invention, there is provided an upper rotating body, an engine disposed on the upper rotating body, an exhaust pipe for discharging exhaust gas of the engine, and the upper rotating body. And an exhaust pipe hole formed in a part of the exterior and capable of discharging exhaust gas discharged from the exhaust pipe to the outside of the upper rotating body. In the engine exhaust device of the construction machine, a diffusion device is provided, which is capable of substantially covering the exhaust pipe hole and diffusing the exhaust gas and discharging the exhaust gas to the outside, from the exterior side of the exterior. is there.

In this case, in the conventional configuration in which the diffusion device is attached to the exhaust pipe, there is a concern that the assembling workability is poor, the exhaust pipe is damaged when the diffusion device is attached / detached, and the life is shortened. The above problem can be solved by attaching the diffusion device to the exterior.

According to a second aspect of the present invention, in the engine exhaust system for a construction machine according to the first aspect, the exhaust pipe hole has an inclined surface whose opening area gradually increases toward the exterior side. It is assumed that.

In this case, since the inclined surface plays a role of guiding the exhaust gas discharged from the engine to the outside, it is possible to prevent the exhaust gas from flowing back to the engine side, and there is no fear of lowering the exhaust efficiency.

[0012] The invention described in claim 3 is the invention according to claim 1 or 2.
In the engine exhaust device for a construction machine described above, the diffusion device falls within a turning radius of the upper turning body.

In this case, since there is no concern that the diffusion device affects the turning radius of the upper rotating body, the work vehicle can perform work without worrying about the diffusion device.

According to a fourth aspect of the present invention, in the engine exhaust system for a construction machine according to any one of the first to third aspects, the exterior is a counterweight.

In this case, since the counterweight itself is a heavy object, the counterweight is not easily affected by vibration generated during operation of the hydraulic excavator, so that there is no fear that the mounting strength of the diffusion device is reduced.

[0016]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a construction machine engine exhaust system according to an embodiment of the present invention. FIG. 1 is a main part detailed view showing an engine exhaust device of a construction machine according to an embodiment of the present invention. FIG. 2 is an enlarged plan view of a portion A shown in FIG. FIG. 3 is an enlarged front view of a portion A shown in FIG. 1 and shows a first embodiment of the collision plate. FIG. 4 is a view showing a second embodiment of the collision plate. In addition,
Components having the same configuration as the prior art are denoted by the same reference numerals.

The exhaust gas from the engine 60 is discharged to the outside through a muffler 61 attached to one side of the engine 60 and an exhaust pipe 62 attached to the muffler 61 and capable of discharging the exhaust gas to the outside. The engine 60
Is surrounded by an exterior 2 which is a part of the appearance of the upper revolving superstructure. The exterior 2 has a substantially arc shape with a turning radius R (in plan view).
The upper revolving unit does not protrude from the lower traveling unit during turning. The exterior 2 is formed with an exhaust pipe hole 2a through which the exhaust port 62a of the exhaust pipe 62 passes. The exhaust pipe hole 2a is formed with an inclined surface 2c whose opening area gradually increases toward the exterior side. The inclined surface 2c serves to guide the exhaust gas discharged from the exhaust port 62a to the outside, thereby preventing the exhaust gas from flowing back to the engine side. On the outer peripheral surface of the exterior 2 and around the inclined surface 2c, there is formed a diffusion device mounting surface 2b that is hollowed out to a diameter larger than the diameter of the inclined surface 2c. Further, a diffusion device 3 capable of diffusing exhaust gas of the engine 60 and discharging the exhaust gas to the outside is detachably mounted on the diffusion device mounting surface 2b.

The diffusion device 3 is provided with the diffusion device mounting surface 2.
b includes a plurality of stays 3a connected by bolts 4 and the like, and a flat collision plate 3b supported by the plurality of stays 3a. It is preferable to form a plurality of elongated holes 5 in the collision plate 3b as shown in FIG.
In this case, the exhaust gas discharged from the exhaust port 62a collides with the collision plate 3b, and a part of the exhaust gas is discharged from the elongated hole 5, but most of the exhaust gas has a bent outflow direction, and Is discharged from between the stays 3a, so that the exhaust port 62a
The exhaust gas is not exhausted to the rear of the vehicle. Further, a plurality of small holes 6 may be provided as shown in FIG. With this, the same effect as that of the elongated hole 5 can be obtained. That is, the collision plate 3b
Is preferably provided with some holes through which part of the exhaust gas passes. Here, the stay 3a is formed in an L-shape, and the collision plate 3b is supported at a position away from the exhaust port 62a. Thus, since the distance between the exhaust port 62a and the collision plate 3b can be maintained, there is no fear that the exhaust efficiency is reduced by the collision plate 3b. In the present invention, since the diffusion device 3 is mounted on the exterior 2 side, the mounting strength can be more reliable than in the case where the diffusion device 3 is mounted on a conventional exhaust pipe. Also,
Even if the exhaust pipe is attached or detached for maintenance or the like, there is no fear of damaging the exhaust pipe, so that the life of the exhaust pipe can be improved. In addition,
Here, the stay 3a is formed in an L-shape, but when the distance between the collision plate 3b and the exhaust port 62a is a distance that does not lower the exhaust efficiency, the stay 3a does not necessarily have to be L-shaped.

FIG. 5 is a side view of the main part showing the state of attachment of the above-mentioned diffusion device 3. The upper revolving unit 52 is provided with the exterior 2 forming a rear outer shell of the upper revolving unit 52. The exterior 2 is configured to have the most protruding portion near the center in a side view, and is formed in a substantially arc shape with a turning radius R in a plan view. An engine 60 is disposed inside the exterior 2, and the exhaust gas of the engine 60 is a muffler 6.
1 through the exhaust pipe 62. The exhaust pipe 62 is provided with an exhaust pipe hole 2 a formed at a lower portion of the exterior 2.
And the exhaust gas passes through the exhaust pipe hole 2a.
Is discharged to the outside. A diffusion device 3 for diffusing the exhaust gas is attached outside the exterior 2 and above the exhaust pipe hole 2a. The diffusion device 3 is arranged so as to be within the turning radius R described above. In this case, since the diffusion device 3 does not protrude from the exterior 2, there is no fear that the diffusion device affects the turning radius.

If the exterior 2 of the present invention is set as a counterweight, the counterweight itself is a heavy object, and therefore, is less susceptible to the vibration generated during the operation of the hydraulic excavator. Don't worry.

[0021]

According to the first aspect of the present invention, in the conventional configuration in which the diffuser is attached to the exhaust pipe, the assembling workability is poor, and the exhaust pipe is damaged when the diffuser is attached or detached, and the life is shortened. However, in the present invention, the above problem can be solved by attaching the diffusion device to the exterior.

According to the second aspect of the present invention, since the inclined surface plays a role of guiding the exhaust gas discharged from the engine to the outside, it is possible to prevent the exhaust gas from flowing back to the engine side and to reduce the exhaust efficiency. There is no.

According to the third aspect of the present invention, there is no concern that the diffusion device affects the turning radius of the upper rotating body, so that the work vehicle can perform work without worrying about the diffusion device.

According to the fourth aspect of the present invention, since the counterweight itself is a heavy object, the counterweight itself is not easily affected by vibration generated during operation of the hydraulic shovel.

[Brief description of the drawings]

FIG. 1 is a detailed view of a main part showing an engine exhaust device of a construction machine according to an embodiment of the present invention.

FIG. 2 is an enlarged plan view of a portion A shown in FIG.

FIG. 3 is an enlarged front view of a part A shown in FIG. 1, showing a first embodiment of the collision plate.

FIG. 4 is a view showing a second embodiment of the collision plate.

FIG. 5 is a side view of a main part showing a mounting state of the diffusion device.

FIG. 6 is a plan view showing a general hydraulic excavator.

FIG. 7 is a detailed view of a main part showing an engine room of the hydraulic shovel shown in FIG. 6;

FIG. 8 is an enlarged view of a main part showing a conventional diffusion device.

[Explanation of symbols]

 2: Exterior 2a: Exhaust pipe hole 2c: Inclined surface 3: Diffusion device 52: Upper revolving unit 60: Engine 62: Exhaust pipe

Claims (4)

[Claims] An upper revolving unit, an engine disposed on the upper revolving unit, an exhaust pipe for discharging exhaust gas of the engine, and an exterior forming at least a part of a rear surface appearance of the upper revolving unit. An exhaust pipe hole drilled in a part of the exterior and capable of discharging exhaust gas exhausted from the exhaust pipe to the outside of the upper revolving unit. A diffusion device capable of substantially covering the exhaust pipe hole and diffusing the exhaust gas and discharging the exhaust gas to the outside. 2. The engine exhaust device for a construction machine according to claim 1, wherein the exhaust pipe hole has an inclined surface whose opening area gradually increases toward an appearance side. 3. The engine exhaust device for a construction machine according to claim 1, wherein the diffusion device is set within a turning radius of the upper turning body. 4. The engine exhaust device for a construction machine according to claim 1, wherein the exterior is a counterweight.