JPH05214932A - Muffler structure - Google Patents

Abstract

PURPOSE:To cantilever-support a muffler with a manifold pipe only and sufficiently secure strength and capacity by welding and fixing the base end of the manifold pipe through the side wall of a muffler main body, and welding and fixing the tip to the faced side wall. CONSTITUTION:A manifold pipe 15 protruded from a muffler main body 14 is connected to an exhaust manifold 13 connected to an engine. The base end section of the manifold pipe 15 is welded and fixed through the lower side wall 16 of the muffler main body 14. The crushed tip 15a of the manifold pipe 15 is welded and fixed to the side face of the muffler main body 14. A steel plate is rounded, butt portions 14b are welded together to form a muffler tube 14A, and the crushed tip section 15a is inserted into an opening made of notches (k) formed on the right and left side wall edges 14b. A weld section 24 of butt end faces serves as an upper side wall. An exhaust outlet 17 made of many small holes is formed inside the muffler main body 14 on the manifold pipe 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a muffler structure suitable for cantilevered support and mounting on an engine, and more specifically, a muffler body equipped with a manifold pipe bolted to an engine exhaust port. Regarding a muffler structure.

[0002]

2. Description of the Related Art Muffler structures are roughly classified into a direct connection type structure in which a box-shaped muffler body is directly bolted to an exhaust port of an engine as shown in Japanese Utility Model Application Laid-Open No. 61-111830. As disclosed in Japanese Patent Laid-Open No. -118079, there is a manifold type structure in which a manifold pipe protruding from a muffler body is bolted to an exhaust manifold connected to an engine. Since the exhaust manifold does not exist in the direct connection type structure, the muffler body can be placed closely to the engine, which has the advantage that the bulk of the engine and muffler can be relatively compacted, but on the other hand, the manifold pipe part is installed inside the muffler body. For this reason, the structure of the muffler becomes complicated, and a large number of bolts are required for the attachment / detachment operation of the muffler, so that the attachment / detachment operability is inferior. The advantages and disadvantages of the manifold structure are upside down of those of the direct connection type structure, and the bulk of the engine and muffler is relatively large, but the structure of the muffler body can be simplified and compared by connecting and disconnecting the exhaust manifold and the manifold pipe The muffler can be attached and detached easily and easily. These structures are selected and set according to the specifications and form of the model in which the muffler is installed.

[0003]

By the way, the following problems have occurred in a tractor adopting a manifold type structure with an emphasis on an easy muffler structure and good detachability. That is, the engine room has to be made as low as possible due to a good front field of view, design restrictions, etc., and it has become difficult to secure a sufficient capacity of the muffler body. In other words, the muffler is usually suspended at least at two points of the manifold pipe and the attachment part provided on the muffler main body on the engine or the body side member, and the location of the muffler main body is made close to the inner side of the bonnet on the upper side of the engine. Generally, it is installed at a position, but the muffler installation space is reduced due to the above restrictions, and the suspension part of the muffler body other than the manifold pipe part cannot be removed or the capacity itself of the muffler cannot be secured sufficiently. The evil has occurred. The present invention, while following the manifold type muffler structure, even if there is a constraint in the engine room space such as a decrease in bonnet height or a curved surface, it is possible to equip a muffler with sufficient strength and sufficient capacity. To aim.

[0004]

In order to achieve the above object, the present invention is to fix a manifold pipe bolted to an engine exhaust port through a side wall of a muffler body by welding.
The tip of the manifold pipe on the side opposite to the engine exhaust port is welded and fixed to the side wall facing the side wall with the tip closed, and the exhaust pipe is formed in the manifold pipe inside the muffler body to form a muffler. It is characterized in that it is configured. The end of the manifold pipe on the side opposite to the engine exhaust port is crushed to form a crushed tip, and the crushed tip is positioned at the welding site between the left and right side wall parts that are abutted and opposed to each other on the side surface of the muffler body. It is convenient to have.

[0005]

In the case of the conventional structure in which the muffler body is also attached to the fixing member by the attachment portion, the manifold pipe is simply welded and connected to the side wall of the muffler body, so that the manifold pipe alone cannot sufficiently support the muffler body. Whereas, the manifold pipe is welded to each of the side walls of the muffler body which face each other with a space therebetween.
With the configuration described above, since the manifold pipe and the muffler body are firmly integrated, it becomes possible to suspend and support the muffler body on the engine with sufficient strength only by the manifold pipe. Therefore, both the mounting portion on the muffler body and the pair mounting portion on the side of the fixing member for the muffler body are not necessary, and the space required for them is contributed to increase the capacity of the muffler body, that is, if the engine room shape is the same, the muffler. If the muffler capacity is the same as the capacity increase, the bonnet can be downsized (the height can be reduced or the curvature of the corners can be increased). As a result, even if there is a restriction on the engine room space such as a decrease in bonnet height or a curved surface, it is possible to equip the muffler with sufficient strength and capacity. According to the configuration of claim 2, since the welding portion between the tip end side of the manifold pipe and the side wall of the muffler is located at the welding portion between the left and right side wall portions that are arranged to face each other on the side surface of the muffler body, the welding between the side wall portions is performed. And the closure tip of the manifold can be welded at once, and the crushed tip of the manifold pipe and the muffler side wall can be welded at the same welding site, and the muffler side wall is provided with a notch for inserting the crushed tip part. It suffices, and processing is easier than when a hole for insertion is formed in the middle portion of the side wall.

[0006]

Therefore, in the muffler structure according to the first aspect of the present invention, the muffler can be cantilevered only by the manifold pipe, so that the height of the bonnet is reduced and the engine room space is curved while following the manifold type muffler structure. Despite the restrictions, it is now possible to equip a muffler with sufficient strength and sufficient capacity. In addition to the above effects, the muffler structure according to the second aspect of the present invention has an advantage that the working cost and the component cost can be reduced because the welding work is easy.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings in the case of a muffler mounted on a tractor.
4 and 5, a tractor is shown, 1 is an engine, 2 is an engine hood, 3 is a muffler, 4 is a cockpit, 5 is front wheels, 6 is rear wheels, and 7 is a fender. The left and right fenders 7, 7 are provided with resin lever guides 10, 11 on which various operating levers 8, 9 are arranged, and the rear portions of the resin guides are integrally raised to form armrests 12, 12. ing. As shown in FIG. 1 and FIG. 2, an exhaust manifold 13 connected to the engine 1 with a large number of bolts is bolted at four points to a thick manifold pipe 15 protruding from the muffler body 14. A muffler 3 having a manifold structure is provided in the engine room R. The manifold pipe 15 has a base end side wall 16 on the lower side of the muffler body 14 having an oval cross-section.
The crushed distal end portion 15a is inserted into the side surface of the muffler main body 14 in a state where the outer peripheral surface is aligned and fixed by welding. That is,
As shown in FIG. 3, a steel plate is rolled to form a butt portion 1 thereof.
4b are welded to each other to form the muffler cylinder 14A. Notches k are formed in the left and right side wall end edges 14b and 14b, and a crushing tip portion is formed in the opening formed by both notches k and k. 15a is inserted and the crushing tip portion 15 is inserted.
A is closed by welding as a single piece, and is crushed by welding all around to weld the tip portion 15a and the muffler body 14 together. In the present embodiment, the welded portion 24 between the mating end faces of the muffler cylinder 14A corresponds to the upper side wall (the side wall that faces the lower side wall 16). The manifold pipe 15 has an exhaust outlet 17 formed by a large number of small holes inside the muffler body 14, and a flange 15 that is a connecting portion with the exhaust manifold 13.
b is provided. The inside of the muffler body 14 is divided into first to fourth expansion chambers 18, 19, 20, 21 and the inner pipe 2
The exhaust gas that has entered the first expansion chamber 18 through the second exhaust chamber 23, the exhaust pipe 23, and the like is supplied to the second expansion chamber 19, the fourth expansion chamber 21, and the third expansion chamber 21.
It passes through the expansion chamber 20 in this order and is discharged from the exhaust pipe 23. Further, as shown in FIG. 2, the muffler 3 is arranged above the left side portion of the engine 1, but the corner portions on the left and right sides of the engine bonnet 2 are bent and formed with a large curvature. The main body 14 is tilted slightly to the left and right to be close to the bonnet inner surface 2a, which contributes to the improvement of the muffler capacity, and the muffler main body 14 is formed in the shape of a long cylinder which can be constructed at a lower cost than the cylindrical shape.

[Other Embodiment] As shown in FIG. 6, the manifold pipe 15 is penetrated through the opposite side walls 16 and 24 and welded all around, and the cover 25 is welded to close the tip of the manifold pipe 15. Things. As shown in FIG. 7, the crushed tip portion 15a is plug-welded without being inserted into the elongated hole 14a of the muffler cylinder 14A.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a sectional side view showing an internal structure of a muffler.

FIG. 2 is a sectional front view of the engine room.

FIG. 3 is a cross-sectional view of a main part showing a mounting structure of a manifold pipe tip.

FIG. 4 is a side view of the tractor.

FIG. 5 is a front view of the tractor.

FIG. 6 is a cross-sectional view showing a first different structure for attaching a manifold pipe tip.

FIG. 7 is a sectional view showing a second alternative structure for attaching the manifold pipe tip.

[Explanation of symbols]

 14 Muffler body 14b Side wall edge 15 Manifold pipe 15a Crushing tip 16,24 Side wall 17 Exhaust outlet

Claims (2)

[Claims] 1. A manifold pipe (15) bolted to an engine exhaust port is attached to a side wall (1) of a muffler body (14).
6) is penetrated and fixed by welding, and a side wall (24) existing opposite the side wall (16) at a front end portion of the manifold pipe (15) on the side opposite to the engine exhaust port is closed. A muffler structure in which an exhaust outlet (17) is formed in the manifold pipe (15) inside the muffler body (14) while being fixed by welding. 2. A crushed tip portion (15) obtained by crushing a tip portion of the manifold pipe (15) opposite to the engine exhaust port.
a) is formed, and the crushed tip portion (15a) is located at the welding portion between the left and right side wall portions (14b), (14b) that are arranged to face each other on the side surface of the muffler body (14). The muffler structure according to item 1.