JP2007154591A - Engine compartment for construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize an engine compartment for a construction machine having an exhaust pipe. <P>SOLUTION: End faces of a plurality of pipelines 21-24 are obliquely cut, and the end faces of the pipelines 21, 22 and pipelines 23, 24 are joined to each other to form the exhaust pipe 20. The thus formed exhaust pipe 20 is formed in bent shape to lead exhaust gas exhausted from an engine 1, to a muffler 17 placed obliquely backward. The degree of freedom in the layout of the muffler 17 is thereby improved to attain miniaturization of the engine compartment 5. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an engine room of a construction machine such as a hydraulic excavator.

There is known an exhaust pipe provided in an engine room of a hydraulic excavator and having an exhaust passage so that exhaust gas discharged from the engine is guided to a muffler (see, for example, Patent Document 1). In the apparatus described in Patent Document 1, an exhaust passage is formed by an exhaust pipe having a bent structure.
JP 2001-26944 A

  However, in the exhaust pipe structure described in Patent Document 1, a space corresponding to the bending radius of the exhaust pipe is required in the engine room, so that the engine room is enlarged.

The engine room of the construction machine according to the present invention has an exhaust pipe that forms an exhaust passage for guiding the exhaust gas exhausted from the engine to the muffler, and the exhaust pipe is connected to a plurality of pipes whose end faces are cut obliquely. It is characterized by being bent into a bent shape.
The exhaust outlet from the engine and the exhaust inlet to the muffler are connected by an exhaust pipe, and the exhaust outlet is opened in one direction in the width direction of the aircraft. An opening may be provided on the other side, and the inlet may be provided on the rear side of the aircraft from the outlet.
In this case, it is preferable to arrange a hydraulic oil tank and / or a fuel tank on an extension line in the width direction of the machine body where the discharge port is provided.

  According to the present invention, since a plurality of pipes whose end faces are obliquely cut are joined together to form a bent exhaust pipe, there is no need to bend the pipe to form an exhaust pipe, and the engine chamber can be downsized. Can do.

Hereinafter, the form of the engine room of the construction machine according to the present invention will be described with reference to FIGS.
1A and 1B are a plan view and a side view of a hydraulic excavator to which the present invention is applied. Hereinafter, as shown in FIG. 1A, the front-rear and left-right directions are defined, and the arrangement of each part will be described according to this definition.

  The hydraulic excavator includes a traveling body 1, a revolving body 2 provided on the traveling body 1 so as to be able to turn, and a work front 3 including a boom, an arm, and a bucket attached to the revolving body 2 so as to be able to turn. . A driver's cab 4 is provided at the left front part of the revolving unit 2, an engine room 5 is provided at the rear thereof, and a counterweight 6 is attached to the rear end of the revolving unit 2. The engine chamber 4 is formed by surrounding the upper part of the revolving frame 2a (FIG. 3) with a cover.

  In this hydraulic excavator, the length of the engine chamber 5 in the front-rear direction is formed short, and a counterweight 6 is formed in an arc shape so as to surround the engine chamber 5. It is located in front of the edge. That is, the hydraulic excavator according to the present embodiment is a hydraulic excavator in which the length from the turning center to the rear end of the turning body 2 is shorter than that of a normal hydraulic excavator and can be turned backward.

  FIG. 2 is a plan view showing the configuration of the revolving structure 2, particularly the configuration inside the engine compartment 5, and FIG. 3 is a view of the inside of the engine compartment 5 as viewed from the side (see view III in FIG. 2). The engine 10 is disposed horizontally in the engine chamber 5 so that the longitudinal direction of the engine 10 faces the width direction of the airframe, and the engine 10 is supported on the turning frame 2a. A cooling fan 11 driven by the engine 10 is attached to the left end portion of the engine 10, and a radiator 12 that exchanges heat between the cooling air blown by the cooling fan 11 and the engine cooling water is disposed on the left side of the cooling fan 11. Has been. A hydraulic pump 13 driven by the engine 10 is attached to the right end portion of the engine 10. In front of the hydraulic pump 13, a fuel tank 14 and a hydraulic oil tank 15 are arranged side by side. These tanks 14 and 15 are supported by the revolving frame 2 a, and their upper end surfaces are located above the muffler 17.

  A turbocharger 16 is disposed on the upper front side of the engine 10, and a muffler 17 is disposed above the hydraulic pump 13. The turbocharger 16 and the muffler 17 are connected by an exhaust pipe 20. Exhaust gas from the engine 10 flows into the turbocharger 16 via an exhaust manifold (not shown). Exhaust gas discharged from the discharge port 16a of the turbocharger 16 is guided to the inlet 17a of the muffler 17 via the exhaust pipe 20, and is discharged outside the engine room via the tail pipe 18 after passing through the muffler 17. The turbocharger 16 constitutes a part of the engine 10, and the exhaust from the turbocharger 16 means the exhaust from the engine 10.

  The discharge port 16a of the turbocharger 16 opens toward the right, and the inflow port 17a of the muffler 17 opens toward the left. The discharge port 16a and the inflow port 17a are provided at substantially the same height. The discharge port 16a is arranged on a straight line L1 in the left-right direction in FIG. 2, and a hydraulic oil tank 15 and a fuel tank 14 are also arranged on the straight line L1. Therefore, the muffler 17 is arranged behind the straight line L1 so as not to interfere with the tank 15, and the inflow port 17a is arranged on the straight line L2 in the left-right direction shifted rearward from the straight line L1.

  As a result, for example, as shown in FIG. 4, the discharge port 16a and the inflow port 17a are arranged on the same straight line L1, and the hydraulic pump is compared with the case where the discharge port 16a and the inflow port 17a are connected by a straight exhaust pipe 200. 13 and the tanks 14 and 15 and the gap SP2 between the muffler 17 and the counterweight 16 can be reduced. As a result, the excess space in the engine compartment 5 is reduced, and the engine compartment 5 can be formed compactly.

  In this case, if the muffler 17 is shifted rearward as shown in FIG. 2, the discharge port 16a and the inflow port 17a cannot be connected by the straight exhaust pipe 200 as shown in FIG. Further, since the exhaust pipe 20 needs to have a certain diameter in order to suppress an increase in the back pressure, for example, an exhaust passage from the turbocharger 16 to the muffler 17 is formed by the bent exhaust pipe 210 as shown in FIG. Then, the bending radius of the pipe becomes large, and the length (passage length) from the discharge port 16a to the inflow port 17a cannot be shortened. As a result, restrictions on the layout of the turbocharger 16 and the muffler 17 become large, and it is difficult to downsize the engine compartment 5. Therefore, in the present embodiment, the exhaust pipe 20 is formed as follows.

  6A is an enlarged cross-sectional view of the exhaust pipe 20 of FIG. 2, and FIG. 6B is an external view of the main part thereof. As shown in FIG. 6A, the exhaust pipe 20 is constituted by a first pipe 21 to a fourth pipe 24 having substantially the same pipe diameter. A flange portion 16b is provided at the discharge port 16a of the turbocharger 16, and a flange portion 21a provided on one end side (left end side) of the first pipe 21 is fastened to the flange portion 16b with a bolt (not shown).

  The other end (right end) of the first pipe 21 is cut obliquely by a vertical plane SF1 that is inclined in the left-right direction so that the end face faces obliquely rearward. One end (left end) of the second pipe 22 is cut obliquely in accordance with the shape of the cut of the first pipe 21, and the cut of the first pipe 21 and the second pipe 22 has the same elliptical shape. The end faces of the first pipe 21 and the second pipe 22 are joined together by butt welding, and the first pipe 21 and the second pipe 22 are integrated to form an exhaust passage (first exhaust pipe 20A) from the engine 1. Forming.

  On the other hand, one end (right end) of the fourth pipe 24 is welded to the inlet 17 a of the muffler 17. The other end (left end) of the fourth pipe 24 is cut obliquely by a vertical surface SF2 that is inclined in the left-right direction so that the end face faces obliquely forward. One end (right end) of the third pipe 23 is cut obliquely in accordance with the shape of the cut of the fourth pipe 24, and the cut of the fourth pipe 24 and the third pipe 23 has the same elliptical shape. The end surfaces of the fourth pipe 24 and the third pipe 23 are joined by butt welding, and the fourth pipe 24 and the third pipe 23 are integrated to form an exhaust passage (second exhaust pipe 20B) to the muffler 17. Forming. The second exhaust pipe 20B is not an independent exhaust pipe because it is welded to the muffler 17. However, the exhaust pipe 20B including such an exhaust pipe 20B is referred to herein as an “exhaust pipe”.

  The other end (left end) of the third pipe 23 is formed to have a slightly larger diameter than the other end (right end) of the second pipe 22. The end of the second pipe 22 is fitted into the end of the third pipe 23, and the periphery thereof is tightened with a band 25 as shown in FIG. 6B, and the first exhaust pipe 20A and the second pipe are connected. The exhaust pipe 20B is fastened integrally. As a result, the exhaust pipe 20 is bent in two stages from the discharge port 16a of the turbocharger 16 to the inflow port 17a of the muffler 17 obliquely rearward to the right, thereby forming a bent exhaust passage. In this case, the end faces of the pipes 21 to 24 are cut obliquely, and the end faces are welded together to form the exhaust passage, so that it is not necessary to provide the outlet 16a and the inlet 17a in consideration of the bending radius of the pipe. The passage length of the exhaust pipe 20 can be made shorter than that shown in FIG.

According to the above embodiment, the following effects can be obtained.
(1) Since the end surfaces of the pipes 21 to 24 are cut obliquely and the end surfaces are welded to form the bent exhaust pipe 20, the exhaust gas is exhausted as compared with the case where the bent exhaust pipe 210 (FIG. 5) is used. The passage length of the pipe can be shortened, and the engine compartment 5 can be reduced in size. Further, it is not necessary to bend a large-diameter pipe, and the exhaust pipe 20 can be easily manufactured.
(2) The exhaust port 16a of the turbocharger 16 and the inflow port 17a of the muffler 17 are provided so as to face each other in the left-right direction, and the inflow port 17a is provided behind the discharge port 16a and is bent obliquely rearward. Since the discharge port 16a and the inflow port 17a are connected, the degree of freedom of arrangement of the muffler 17 is increased, and space saving of the engine room 5 can be realized. As a result, it is possible to easily configure a hydraulic excavator with a small rear turning.
(3) Since the tanks 14 and 15 are arranged on the extension line L1 of the discharge port 16a, the tanks 14 and 15 can be arranged close to the engine 10 and the excess space in the engine chamber 4 is reduced. be able to.
(4) Since the first exhaust pipe 20A and the second exhaust pipe 20B are connected by the band 25, the attachment position of the exhaust pipe 20 can be adjusted, and the exhaust pipe 20 can be easily attached.

  In addition, arrangement | positioning of the components in an engine compartment, and the direction which the discharge port 16a and the inflow port 17a open are not restricted to what was mentioned above. In the above embodiment, the exhaust pipe 20 is bent in two stages. However, if a plurality of pipes whose end faces are cut obliquely are joined together to form a bent exhaust passage, the exhaust pipe 20 The shape is not limited to that described above. Although the discharge port 16a and the inflow port 17a are provided at the same height, they may not be the same height. In that case, the exhaust pipe 20 may be bent in the vertical direction.

  Although the first exhaust pipe 20A and the second exhaust pipe 20B are connected by the band 25, they may be connected via other connecting means such as bolts. The first exhaust pipe 20 </ b> A and the second exhaust pipe 20 </ b> B may be welded, and the exhaust pipe 20 may be provided integrally with the muffler 17. In this case, an attachment position adjusting mechanism may be provided on the flange portion 16b. Alternatively, the muffler 17 may be provided with a flange portion, and the pipe 24 may be fastened to the flange portion via a bolt.

  As shown by a solid line in FIG. 7, a pair of pipes 21, 22 or 23, 24 may be joined via pipes 26 whose both end faces are cut obliquely. As a result, the exhaust passage is bent more gently than when the pipes 21, 22 or 23, 24 are joined together (dotted line in FIG. 7), and the pressure loss in the passage can be reduced. Although the hydraulic oil tank 15 and the fuel tank 14 are arranged on the extension line L1 of the discharge port 16a, only one of them may be arranged.

  Although the above embodiment is applied to a hydraulic excavator, the present invention can be similarly applied to other construction machines having an exhaust pipe. That is, the present invention is not limited to the engine room of the construction machine of the embodiment as long as the features and functions of the present invention can be realized. The above description is merely an example, and when interpreting the invention, there is no limitation or restriction on the correspondence between the items described in the embodiment and the items described in the claims.

(A) is a top view of the hydraulic excavator to which this invention is applied, (b) is a side view. The top view which shows the internal structure of the engine room of the construction machine which concerns on embodiment of this invention. FIG. 3 is an arrow III view of FIG. 2. The figure explaining the effect of this invention by contrast with FIG. The figure which shows an example of the exhaust pipe of a bending structure. (A) is an expanded sectional view of the exhaust pipe of a figure, (b) is the one part external view. The figure which shows the modification of FIG.

Explanation of symbols

5 Engine chamber 10 Engine 14 Fuel tank 15 Hydraulic oil tank 16a Discharge port 17 Muffler 17a Inlet port 20 Exhaust pipe 21 First pipe 22 Second pipe 23 Third pipe 24 Fourth pipe

Claims (3)

An exhaust pipe that forms an exhaust passage for guiding exhaust gas discharged from the engine to the muffler;
The engine room of a construction machine, wherein the exhaust pipe is bent by joining a plurality of pipes whose end faces are cut obliquely. In the engine room of the construction machine according to claim 1,
The exhaust pipe communicates with an exhaust outlet from the engine and an exhaust inlet to the muffler, the exhaust opening is provided to open in one width direction of the fuselage, and the inlet is connected to the exhaust outlet. An engine room of a construction machine, wherein the engine room is provided so as to be opposed to the other in the width direction of the machine body, and the inflow port is provided on the rear side of the machine body with respect to the discharge port. In the engine room of the construction machine according to claim 2,
An engine room of a construction machine, wherein a hydraulic oil tank and / or a fuel tank are arranged on an extension line in a width direction of a machine body provided with the discharge port.

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