JP2604904Y2 - Exhaust structure of work machine - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust part structure of a working machine.

[0002]

2. Description of the Related Art Conventionally, in an exhaust portion of a working machine or the like, a tail pipe outlet hole is formed in an engine cover, and a tip end of a tail pipe of a silencer connected to an engine projects outside through the outlet hole. Structure is taken.

[0003] A tail pipe cover is provided in the outlet hole to prevent rainwater, car wash water and the like from entering the inside of the engine cover and to improve the appearance.

[0004]

However, in the conventional structure described above, the wind noise (high frequency noise) of the exhaust gas from the tailpipe.
However, there is a problem that the exhaust noise is increased due to resonance and amplification at the tail tube cover.

Therefore, the above noise can be reduced to some extent by increasing the size of the tailpipe cover or changing the length of the tailpipe or the like to a large extent. Secondary troubles such as obstruction, an increase in the mass of the tailpipe cover to induce vibration, damage to the engine cover when the vehicle body receives an impact, and impairment of the appearance occur.

[0006]

According to the present invention, a substantially tubular tail pipe for covering a tail pipe end of a silencer connected to an engine is provided on a wall of an engine cover which covers an engine room of a working machine. Forming a cover, covering the inner peripheral surface of the tail pipe cover with a heat-resistant sound absorbing material, making the inner diameter of the tail pipe cover a stepped small diameter inner diameter, and having the same stepped small diameter heat resistant sound absorption Along with placing the tail tube end near the beginning of the material,
It is an object of the present invention to provide an exhaust part structure of a working machine, characterized in that a tail pipe end is opened toward a start end of the heat resistant sound absorbing material.

[0007]

According to the above structure, the wind noise of the exhaust gas from the tail pipe is absorbed by the heat-resistant sound absorbing material covering the inner peripheral surface of the tail pipe cover, thereby preventing resonance and amplification. Exhaust noise can be significantly reduced without enlarging or extending the tailpipe, and the secondary problems described above do not occur.

In particular, since the harsh exhaust noise (high-frequency noise) is effectively absorbed by the heat-resistant sound absorbing material, the sound quality of the exhaust is improved and the perceived noise level can be reduced.

Also, noise such as mechanical noise generated in the engine room is absorbed by the heat-resistant sound absorbing material.
These noises are prevented from leaking outside through the tail pipe outlet.

In addition, since the sound absorbing material has heat resistance, the sound absorbing performance is not deteriorated by the heat of the exhaust gas, and the above-described noise reducing effect can be maintained for a long period of time. Furthermore, the inner peripheral surface of the tail pipe cover is covered with a heat-resistant sound absorbing material, and the inner diameter of the tail pipe cover is made into a stepped small-diameter inner diameter. The tail tube end is located near the tail tube and the tail tube end is opened toward the beginning of the heat-resistant sound-absorbing material, so that noise such as mechanical noise generated in the engine room can be reduced. This noise can be prevented from leaking to the outside.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an excavator A equipped with an exhaust part structure B according to the present invention. A turning table 12 is provided, and a turning body 20 is mounted on the upper surface of the turning table 12, and is rotated left and right by a hydraulic motor (not shown) interposed between the turning table 12 and the turning body 20. I try to make it.

On the turning body 20, an engine room 23 equipped with an engine connected to a hydraulic pump is mounted at the rear, an operator's cab 24 is mounted at the front, and a bracket 25 to be described later projects at the center of the front edge. To support the base end of the excavation section 26.

The excavating section 26 is constructed by connecting a boom 27, an arm 28 and a bucket 29 in the above order from the base end side, and a hydraulic cylinder 27a for lifting and lowering the boom is provided between the bracket 25 and the boom 27. A hydraulic cylinder 28a for raising and lowering the arm is interposed between the boom 27 and the arm 28, and a hydraulic cylinder 29a for raising and lowering the bucket is interposed between the arm 28 and the bucket 29. Like that.

In the excavator A, the exhaust part structure B according to the present invention is formed on the upper surface of the wall 31 of the ceiling wall of the engine cover 30 covering the engine room 23,
As shown in FIGS. 2 and 3, a tail pipe cover 34 for leading out a tail pipe 33 of the silencer 32 connected to the engine E is formed.

That is, a tail pipe outlet 35 is formed in the wall 31 of the ceiling wall of the engine cover 30, and the tail pipe outlet 35 is inserted into the tail pipe outlet 35.
The tail end of the tail pipe cover 34 is fixed to the tail pipe cover 34 around the tail pipe lead-out hole 35 while the terminal end of the tail pipe 33 is projected slightly upward from the wall 31. 34 is extended obliquely upward, and its extended end is vertically notched to form a tail tube cover 34 that opens rearward.

A portion of the inner peripheral surface of the tail tube cover 34 from a position slightly outside the end of the tail tube 33 to the end of the tail tube cover 34 is covered with a heat-resistant sound absorbing material a. The inner diameter d of the portion covered with the sound absorbing material a is
Of the heat-resistant sound-absorbing material a is smaller than the inner diameter D in the vicinity of the end of the tail tube 33.
33 The terminal end is opened.

As shown in FIG. 2, the heat-resistant sound-absorbing material a is formed by first forming the inner peripheral surface of the tail tube cover 34 into a heat-absorbing material having heat resistance such as glass wool and having good sound absorption characteristics in a high frequency range. The inner peripheral surface that comes into contact with the exhaust gas is covered with a punching metal 36 having countless through holes.

As the heat-resistant sound-absorbing material a, besides the above-mentioned glass wool, metal wool such as steel wool, heat-resistant fiber such as asbestos, or a material obtained by molding an inorganic foam into a cylindrical shape may be used. it can.

The embodiment of the present invention is configured as described above, and the exhaust gas discharged from the engine E is supplied to the muffler 32.
Through the tail tube 33 to the outside.

When the exhaust gas is discharged, the tail pipe 33
The wind noise (high-frequency noise) of the exhaust gas is emitted to the outside from the end portion. However, the wind noise is absorbed by the heat-resistant sound absorbing material a that covers the inner peripheral surface of the tail pipe cover 34, and resonance and amplification occur. Therefore, the exhaust noise emitted to the outside can be reduced without increasing the diameter of the tailpipe cover or extending the tailpipe.

In particular, since harsh high-frequency wind noise is absorbed, the perceived noise level is greatly reduced.

The inner diameter d of the portion covered with the heat-resistant sound absorbing material a is smaller than the inner diameter D near the end of the tail pipe 33 of the tail pipe cover 34, so that mechanical parts generated in the engine room 23 are formed. Noise such as noise is also absorbed by the heat-resistant sound-absorbing material a, and the noise is prevented from leaking to the outside through the tail pipe outlet 35.

The heat-resistant sound-absorbing material a does not deteriorate its sound-absorbing performance due to the heat of the exhaust gas due to the heat resistance, and the inner peripheral surface in contact with the exhaust gas is covered with the punching metal 36. Since a is protected from the wind pressure of the exhaust gas, the noise reduction effect can be maintained for a long time.

In the above embodiment, the engine room 23
The exhaust structure B disposed on the upper surface of the wall body 31 of the ceiling wall of the engine cover 30 covering the engine cover 30 has been described. Can be provided.

FIGS. 4 to 6 show an embodiment in which an air chamber 40 for reducing the intake noise of the engine E is provided integrally with an air cleaner 41. FIG.

FIGS. 4 and 5 show that the air cleaner 41 is formed in a substantially cylindrical shape, and a substantially cylindrical air chamber 40 with a bottom is provided at the end of the air discharge hole 42 side. An air supply hole 43 is formed on the surface, and the air supply hole 43 is connected to the engine E via an air suction pipe 44.

FIG. 6 shows an air supply hole 53 formed in the bottom surface of an air chamber 50 formed in the same manner as described above, and the air supply hole 53 is connected to the engine E via an air suction pipe 54. . 51 is an air cleaner.

The air chambers 40 and 50 can be manufactured by press-forming a steel plate, molding rubber or plastic, or the like, and attached to the air cleaners 41 and 51 by means such as welding, bonding, fitting, and band fastening. be able to.

With this configuration, the air cleaner and the air chamber disposed near the engine are integrated, so that the space in the engine room can be made compact, and the engine cover can be made low.

Further, by integrally forming air chambers adapted to various air cleaners, it is possible to standardize parts and reduce costs.

FIGS. 7 and 8 show a mounting structure of a floor mat 60 to be stretched on the floor of the operating section of the working machine.

As shown in the figure, the mounting structure includes a projection 61 projecting from the lower surface of the floor mat 60, a plug 70, and a floor surface.
And a mounting hole 81 formed at 80.

The floor mat 60 is made of rubber, soft plastic, or the like, and has a substantially cylindrical projection 61 formed on the lower surface, and a plug insertion hole 63 having a depth extending from the upper surface to an intermediate portion of the projection 61 on the lower surface. A notch 64 is formed from the bottom surface of the projection 61 to the middle part.

In the plug 70, a rod 72 is erected at the center of the upper end surface of a substantially cylindrical plug main body 71 having a conical surface at the lower end, and a small hole is formed at the upper end of the rod 72 to form a ring 74. Chained.

A mounting hole 81 corresponding to the projection 61 is formed on the floor surface 80.

This embodiment is constructed as described above. To attach the floor mat 60 to the floor surface 80, as shown in FIG.
By inserting the plug body 71 from above, and then press-fitting the plug body 71 into the cut 64 through the plug insertion hole 63, as shown in FIG. The floor mat 60 can be securely fixed to the floor surface 80.

When the ring 74 is tilted, the upper surface of the floor mat 60 becomes substantially smooth, and it is possible to prevent the floor mat 60 from tripping.

To remove the floor mat 60, raise the ring 74, grasp it, and pull out the plug 70 from the plug insertion hole 63. Then, the outer shape of the projection 61 is restored and the mounting hole 81 becomes the same shape. The above engagement is released, and the floor mat
60 can be easily removed.

With the above configuration, the floor mat 60 is turned up and lost due to the wind when transporting the work machine by truck.
Further, in order to prevent this, the mounting structure is prevented from being complicated, and attachment / detachment is prevented from being troublesome.

Also, since no screws or the like are used for mounting, no tools are required for mounting and dismounting, and the plug 70 does not come off even when stepping on the mounting portion, thereby preventing the floor mat 60 from coming off accidentally.

[Brief description of the drawings]

FIG. 1 is an overall side view of an excavator having an exhaust unit structure according to the present invention.

FIG. 2 is an explanatory cross-sectional view showing the exhaust unit structure.

FIG. 3 is an explanatory front view showing the exhaust part structure.

FIG. 4 is a side view of the air chamber.

FIG. 5 is a sectional side view of the air chamber.

FIG. 6 is a side view of an air chamber according to another embodiment.

FIG. 7 is a sectional view showing a floor mat mounting structure.

FIG. 8 is a sectional view showing a floor mat mounting structure.

[Explanation of symbols]

 A Work machine a Heat resistant sound absorbing material E Engine 30 Engine cover 31 Wall 32 Silencer 33 Tail tube 34 Tail tube cover

──────────────────────────────────────────────────続 き Continuing on the front page (72) Sadakazu Nakajima 1-32 Chayacho, Kita-ku, Osaka, Osaka Inside Yanmar Diesel Co., Ltd. (72) Masami Kondo 1-32 Chayacho, Kita-ku, Osaka, Osaka No. Yanmar Diesel Co., Ltd. Examiner Hiroshi Abe (56) References Japanese Utility Model Sho 51-122988 (JP, U) Japanese Utility Model Sho 51-12832 (JP, U) Japanese Utility Model Sho 59-9933 (JP, Y2) ( 58) Field surveyed (Int. Cl. ⁷ , DB name) F01N 1/10

Claims (1)

(57) [Scope of request for utility model registration] An engine (3) is mounted on a wall (31) of an engine cover (30) covering an engine room (23) of a work machine (A).
E) Form a substantially tubular tail pipe cover (34) to cover the end of the tail pipe (33) of the silencer (32) connected to the muffler (32), and heat-proof the inner peripheral surface of the tail pipe cover (34). Tail tube covered with a water absorbing material (a)
The inside diameter (D) of the cover (34) is changed to the small inside diameter (d) of the step.
And, heat-resistant sound-absorbing material which are at the same stepped small diameter form (a)
The tail end of the tail tube (33) is located near the start end , and the heat resistance is the same.
Open the end of the tail tube (33) toward the beginning of the sound absorbing material (a)
The exhaust unit structure of the working machine, characterized in that it is made to work.