JPH10266854A - Tail pipe structure of engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent water droplet from dropping onto a car body for example, by providing an engine with tail pipe structure in which water droplet is not exhausted. SOLUTION: By attaching annular water-droplet holding member 2 which is made of water absorptive and heat-resistant material such as glass fiber to tip inner periphery of a tail pipe 1, the water-droplet holding member 2 absorbs water-droplet which generates by dew condensation of steam which is being exhausted at low temperature for example in winter time in an exhaust pipe and moves along the inside peripheral wall of the tail pipe 1, and the droplet is effectively prevented from splashing from a tip opening of the tail pipe 1. A plate droplet catching member made of heatresistant and gas- permeable material can be arranged in the downstream side of the water-droplet holding member 2 on the tip part inside periphery of the tail pipe 1 such that passage part enables exhausted gas to flow is formed between the member 2 and the tip inside periphery of the tail pipe 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine tail pipe and, more particularly, to a technique for preventing water droplets generated by the condensation of water vapor in exhaust gas from being discharged from the tail pipe.

[0002]

2. Description of the Related Art Conventionally, a vehicle is provided with a tail pipe which constitutes an exhaust pipe portion from an engine muffler to a rear end (see Japanese Patent Application Laid-Open No. Hei 8-42322). Incidentally, a large amount of water vapor is contained in exhaust gas discharged from an engine mounted on a vehicle or the like.

[0003] Therefore, when the temperature is low in winter or the like, water vapor in the exhaust is condensed in the exhaust pipe and is discharged as water droplets from the tail pipe. In a normal vehicle, there is no problem even if it is discharged from the tail pipe as water droplets.

[0004]

However, in a special vehicle such as a construction machine, a tail pipe may be installed on the vehicle body. In the case of a conventional tail pipe, water droplets discharged from the tail pipe may be on the vehicle body. And the vehicle body may be soiled. The present invention has been made in view of the above, and it is an object of the present invention to prevent, for example, water drops from falling onto a vehicle body by adopting a tail pipe structure that takes measures to prevent water drops from being discharged.

[0005]

Therefore, the invention according to claim 1 has water absorption and heat resistance on the inner peripheral surface of the distal end portion of the tail pipe constituting the exhaust pipe portion from the muffler to the rearmost end of the engine. An annular water droplet holding member made of a material is mounted.

According to a second aspect of the present invention, an annular gap is formed between one end of the outer peripheral surface of the tail pipe and the other end of the outer peripheral surface of the tail pipe. And a water-drop holding member is mounted on the outer peripheral surface of the other end of the mounting member, and the water-drop holding member is mounted at the gap.

According to a third aspect of the present invention, a plate-shaped water droplet catching member made of a heat-resistant and air-permeable material is provided on the inner peripheral surface of the distal end portion of the tail pipe downstream of the water droplet holding member. It is characterized in that it is disposed while forming a passage portion that enables the flow of exhaust gas between itself and the inner peripheral surface.

According to a fourth aspect of the present invention, an outer circumferential surface at one end is press-fitted into an inner circumferential surface at a distal end of the tail pipe, and an outer circumferential surface at the other end is formed into an annular gap between the inner circumferential surface at the distal end of the tail pipe. A cylindrical member having an outer peripheral wall at one end of the mounting member and a ventilation opening formed at a distal end wall is fixedly provided at one end of the mounting member, and the water droplet capturing on the distal end wall of the cylindrical portion is provided. It is characterized by mounting a member.

The invention according to claim 5 is characterized in that the material of the water droplet holding member is a fiber. The invention according to claim 6 is characterized in that the material of the water droplet capturing member is a nonwoven fabric. The invention according to claim 7 is characterized in that the tail pipe is installed on a vehicle body.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an embodiment of the present invention. In this drawing, a tail pipe 1 constituting an exhaust pipe portion from a muffler (not shown) to the rear end of the engine is shown.
Are arranged to extend vertically from the rear end of the muffler and then extend horizontally.

The end face of the tail pipe 1 is cut obliquely so that the opening is directed downward, and the upper side wall functions as an eave for preventing rain or the like from entering the tail pipe. . Here, an annular water droplet holding member 2 made of a material having water absorbency and heat resistance, for example, glass fiber or the like, is attached to the inner peripheral surface of the distal end portion of the tail pipe 1.

In this case, the outer peripheral surface of the large diameter portion 3A at one end is press-fitted into the inner peripheral surface of the distal end of the tail pipe 1, and the outer peripheral surface of the small diameter portion 3B at the other end is in contact with the inner peripheral surface of the distal end of the tail pipe 1. A substantially cylindrical metal mounting member 3 having an annular gap therebetween is provided. The water droplet holding member 2 is fastened to an outer peripheral surface of a small diameter portion 3B of the mounting member 3 by a retaining ring 4 such as a wire. The water drop holding member 2 is mounted and mounted at the gap.

The mounting member 3 is formed by press working or the like. The peripheral wall of the large-diameter portion 3A is slightly curved, and a slit 3a is formed in a part thereof. 1 facilitates press-fitting into the inner peripheral surface of the distal end portion. In such a configuration, when the temperature is low in winter or the like, the water vapor in the exhaust is condensed in the exhaust pipe and becomes water droplets 5, moves along the inner peripheral wall of the tail pipe 1, and is scattered from the opening at the tip thereof. Since the water droplet holding member 2 is located immediately before the front end opening, water is absorbed here, and water droplets are effectively prevented from being scattered from the front end opening of the tail pipe 1.

The water droplet holding member 2 temporarily holds water, but after the dew water has run out, the held water evaporates due to exhaust heat and is released to the outside as water vapor. Therefore, the water drop holding member 2 can be used as long as it does not cause clogging,
No need to replace. Further, since the water droplet holding member 2 can be mounted simply by press-fitting the mounting member 3 on which the water droplet holding member 2 is mounted to the tail pipe 1, the water droplet holding member 2 can be easily applied to an existing tail pipe.

Next, another embodiment of the present invention will be described with reference to FIG. In this embodiment, a plate-shaped water droplet capturing member 6 made of a heat-resistant and air-permeable material is provided on the inner peripheral surface of the distal end portion of the tail pipe 1 on the downstream side of the water droplet holding member 2 on the inner peripheral surface of the distal end portion of the tail pipe 1. It is arranged while forming a passage portion that allows the flow of exhaust gas.

In this case, the outer peripheral surface of the large diameter portion 7A at one end is fitted to the inner peripheral surface of the distal end of the tail pipe 1, and the outer peripheral surface of the small diameter portion 7B at the other end is connected to the inner peripheral surface of the distal end of the tail pipe 1. A substantially cylindrical mounting member 7 having an annular gap portion is provided at one end of the mounting member 7 and a ventilation opening 8 is formed at an outer peripheral wall and a distal end wall.
A tubular member 8 formed with A and 8B is fixed by welding or the like, and the water droplet catching member 6 is mounted on a distal end wall of the tubular member 8.

The water droplet catching member 6 is, for example, flame resistant,
A flame-retardant non-woven fabric that has been subjected to adhesive processing is used, and is attached to the tip wall of the tubular member 8 and is formed of the tip wall of the tubular member 8 and the annular holding plate 9 spot-welded to the tip wall. It is clamped and fixed between. In this configuration, water droplets moving along the inner peripheral wall of the tail pipe 1 are absorbed by the water droplet holding member 2 immediately before the front end opening of the tail pipe 1 as in the embodiment of FIG. Is effectively prevented from being scattered from the water droplets, and when the exhaust gas passes through the water droplet catching member 6 located downstream of the water droplet holding member 2, the water droplets that pass through together with the exhaust gas are trapped by the water droplet catching member. 6 captured.

The exhaust gas discharged from the tail pipe 1 is discharged through the ventilation openings 8A and 8B of the cylindrical member 8 without receiving any air resistance to the outside. In this embodiment, similarly to the case of the water droplet holding member 2, the water droplet capturing member 6
The water trapped in is evaporated by the exhaust heat and released to the outside as water vapor. Therefore, the water droplet catching member 6 can be used as long as it does not cause clogging, and need not be replaced.

According to each of the above embodiments, in a special vehicle such as a construction machine, even when a tail pipe is installed on the vehicle body, there is a possibility that water drops may fall on the vehicle body and contaminate the vehicle body. Disappears.

[0020]

As described above, according to the first aspect of the present invention, since water droplets are absorbed and held by the water droplet holding member, it is difficult for water droplets to be carried away from the tail pipe tip to the outside by the exhaust flow. That is, it is possible to prevent the water droplets from being discharged from the tip to the outside.

According to the second aspect of the present invention, the water droplet holding member can be easily attached to the tail pipe, and can be easily applied to an existing tail pipe. According to the third aspect of the present invention, in addition to the water absorbing action of the water droplet holding member, the water droplet which is likely to flow out by the exhaust can be captured by the water droplet capturing member, so that the water droplet is discharged to the outside from the tail pipe tip. Can be suppressed more effectively.

According to the fourth aspect of the present invention, the water drop holding member and the water drop catching member can be easily attached to the tail pipe, and can be easily applied to an existing tail pipe. According to the invention according to claim 5, the water droplet holding member can be easily manufactured by using fibers. According to the invention according to claim 6, the water droplet catching member can be easily made of a nonwoven fabric.

According to the invention according to claim 7, in a special vehicle such as a construction machine, even when a tail pipe is installed on the vehicle body, water drops fall on the vehicle body and stain the vehicle body. There is no fear.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tail pipe 2 Water drop holding member 3 Mounting member 6 Water drop catching member 7 Mounting member 8 Tube member 8A, 8B Vent opening

Claims (7)

[Claims] An annular water droplet holding member made of a water-absorbing and heat-resistant material is mounted on an inner peripheral surface of a tip portion of a tail pipe constituting an exhaust pipe portion from a muffler to a rear end of an engine. Engine tail pipe structure. 2. An approximately cylindrical shape having one end outer peripheral surface press-fitted into the distal end inner peripheral surface of the tail pipe, and the other end outer peripheral surface having an annular gap between the tail pipe inner peripheral surface. 2. The engine according to claim 1, wherein a mounting member is provided, the water droplet holding member is mounted on an outer peripheral surface of the other end portion of the mounting member, and the water droplet holding member is mounted so as to be located in the gap. Tail pipe structure. 3. A plate-like water droplet catching member made of a heat-resistant and air-permeable material is provided between the inner peripheral surface of the tail pipe and the inner peripheral surface of the tail pipe downstream of the water droplet holding member. 2. The structure of a tail pipe of an engine according to claim 1, wherein said passage is formed while forming a passage portion through which exhaust gas can flow. 4. An approximately cylindrical shape having one end outer peripheral surface press-fitted into the distal end inner peripheral surface of the tail pipe, and the other end outer peripheral surface having an annular gap between the tail pipe inner peripheral surface. A mounting member is provided, and a cylindrical member having an outer peripheral wall and a ventilation opening formed in a distal end wall is fixedly provided at one end of the mounting member, and the water droplet capturing member is mounted on the distal end wall of the cylindrical portion. 4. The structure of an engine tail pipe according to claim 3, wherein: 5. The structure of an engine tail pipe according to claim 1, wherein the material of the water droplet holding member is a fiber. 6. The structure of an engine tail pipe according to claim 3, wherein the material of the water droplet catching member is a nonwoven fabric. 7. The structure of an engine tail pipe according to claim 1, wherein said tail pipe is installed on a vehicle body.