JP5937738B1 - Tail pipe for exhaust muffler - Google Patents

Abstract

An exhaust muffler tail pipe capable of obtaining an effective effect by increasing the exhaust efficiency and corresponding to the type and type of an internal combustion engine is provided. A tail pipe 10 is provided to be attached to an exhaust side end portion of a vehicle exhaust muffler. The inner cylinder 12B is arranged inside the outer cylinder 12A. A rectifying cylinder 13 through which exhaust gas passes is provided at the center of the inner cylinder 12B. A plurality of fins 11 through which exhaust gas passes while turning on the outer surface of the flow straightening cylinder 13 are provided. A large number of dimple-like recesses 10 </ b> A are formed on the exhaust gas contact surface of the fin 11. The exhaust gas exhaust efficiency is increased. [Selection] Figure 4

Description

  The present invention relates to an exhaust muffler tail pipe mounted on an exhaust side end portion of an exhaust structure, and enhances engine performance such as power and torque, and can be used according to the type and type of an internal combustion engine. It is about.

  Conventionally, by forming dimples (dents) on the surface of an object, the effect of generating turbulent flow (lowering the critical Reynolds number of the object), called the Magnus effect, and the effect of suppressing drag are known. . Such dimple effect is practically used mainly as an effect of extending the flight distance of the golf ball.

  On the other hand, by adopting dimple-like irregularities in the exhaust structure of the internal combustion engine, there has been proposed an exhaust structure that improves the power of the internal combustion engine, improves fuel efficiency, or reduces exhaust noise (see Patent Documents 1 to 3). ).

  The exhaust pipe for an automobile engine described in Patent Document 1 describes a configuration in which a plurality of protrusions are formed on the inner wall surface of the exhaust pipe. In order to form this protrusion, a steel ball collides with the outer surface of the pipe to form a dimple-shaped recess on the outer peripheral surface of the pipe, and this recess becomes a plurality of protrusions on the inner wall surface of the exhaust pipe. In the cited document 1, this projection increases the flow rate of the exhaust gas, reduces the back pressure in the exhaust pipe, and improves the engine output and fuel consumption.

  Further, the engine exhaust device described in Patent Document 2 describes a configuration in which a large number of small irregularities are provided on the inner wall surface of an exhaust gas circulation pipe. This small unevenness is a combination of a dimple-like concave portion and a convex portion formed by a hill-like ridge. If this small unevenness is formed in the exhaust gas flow pipe, the exhaust gas flow resistance is reduced, the back pressure of the engine is lowered, and the engine output and fuel consumption are favorably affected.

  Further, the exhaust system structure of the internal combustion engine described in Patent Document 3 shows an exhaust system structure in which a dimple-like recess is formed on the inner surface of the exhaust pipe by embossing. The concave portion formed on the inner surface of the exhaust pipe increases the wall noise between the sound wave of the exhaust noise and the inner surface of the exhaust pipe, and the sound is also absorbed in the exhaust pipe, thereby reducing the exhaust noise inside the exhaust pipe. That's it.

  On the other hand, as described in Patent Document 4, the applicant attaches to the exhaust side end portion of the exhaust pipe of the exhaust muffler to improve the exhaust efficiency, thereby reducing the output loss and improving the silencing performance. Muffler cutter (hereinafter referred to as tail pipe) patent. This tail pipe is provided with a central flow passage through which exhaust gas passes linearly and an outer peripheral flow passage through which exhaust gas passes while spirally turning by arranging a plurality of fins surrounding the central cylinder.

  Since the exhaust gas passing through the fins of the outer peripheral flow passage is discharged while turning in a substantially spiral shape, centrifugal force acts, and the pressure in the central flow passage portion becomes lower than the pressure in the outer peripheral flow passage portion. Accordingly, the exhaust gas fed into the tail pipe is smoothly discharged at a high speed by the outer peripheral flow passage and the central flow passage provided with fins. As a result, exhaust efficiency is improved and engine output loss is reduced.

Japanese Utility Model Publication No. 63-110618 Japanese Utility Model Publication No. 1-174514 Japanese Patent Laid-Open No. 11-324667 Japanese Patent No. 4174789

  In the exhaust structures described in Patent Documents 1 to 3, the back pressure of the engine decreases due to the unevenness formed on the inner surface of the exhaust pipe. As a result, the engine output and fuel consumption are favorably affected, and The resistance is that the exhaust noise inside the exhaust pipe can be reduced.

  However, in the exhaust structures described in Patent Documents 1 to 3, all the positions where the irregularities are formed are arranged inside the exhaust pipe located before and after the muffler (silencer). In the experiment conducted by the present applicant, when a dimple-shaped recess is formed at such a position, the exhaust efficiency varies greatly depending not only on the length of the exhaust pipe but also on the structure of the muffler (silencer) and the difference in the exhaust amount. In addition, it has been found that a stable and effective effect cannot be obtained. As a result, the effects of the engine output, etc. claimed in the exhaust structures described in Patent Documents 1 to 3 are limited to the effects on the test, and the effective effects that can be obtained by mounting on an actual vehicle are obtained. It is not done.

  Moreover, with the spread of reciprocating engines and diesel engines, as well as hybrid engines, the current vehicle is rapidly changing the form of the internal combustion engine and the structure of the muffler (silencer). It is expected that effective effects can be obtained in common with various internal combustion engines and muffler (silencer) structures.

  On the other hand, in the exhaust structure described in Patent Document 4, the exhaust gas is made high-speed and smooth by the outer peripheral flow passage provided with a plurality of fins provided in the tail pipe and the central flow passage surrounded by the outer peripheral flow passage. Can be discharged. In addition, since the tail pipe is configured to be mounted on the exhaust side end of the exhaust pipe farthest from the internal combustion engine and the muffler (silencer) in the exhaust structure, it can be mounted on various vehicle mufflers.

  The structure of this tail pipe has been proven to improve the engine performance of internal combustion engines, and the patented product is still manufactured and sold as a long-selling product, and the effectiveness obtained by mounting it on an actual vehicle is recognized. Yes.

  Therefore, the present inventor has improved the engine performance such as power and torque by improving the structure of the tail pipe installed at the end of the exhaust side, and obtained more effective than ever obtained by mounting it on an actual vehicle. In addition, an object of the present invention is to provide a tail pipe for an exhaust muffler that can be adapted to the types and types of internal combustion engines such as reciprocating engines, diesel engines, and hybrid engines.

In order to achieve the above-mentioned object, the first means in the present invention is that the tail pipe 10 mounted on the exhaust side end portion of the exhaust muffler for a vehicle, the cylinder 12 constituting the tail pipe 10 and the center of the cylinder 12 And a plurality of fins 11 disposed between the rectifying cylinder 13 and the cylinder 12 are provided on the outer surface of the rectifying cylinder 13. The exhaust gas is arranged so as to pass while swirling spirally, and one side or both sides of the fin 11 serving as an exhaust gas contact surface, and a part of the surface of the cylindrical body 12 in contact with the exhaust gas Alternatively, a large number of dimple-like recesses are formed in any or all of the entire surface and a part or the entire surface of the rectifying cylinder 13 that contacts the exhaust gas .

In the second means, the cylindrical body 12 of the tail pipe 10 has a cylindrical shape having the same diameter in the exhaust direction, a tapered shape in which the diameter in the exhaust direction is enlarged, or an inverse in which the diameter in the exhaust direction is narrowed. It is formed in a tapered shape.

  According to the first aspect of the present invention, the cylinder 12 constituting the tail pipe 10, the rectifying cylinder 13 disposed at the center of the cylinder 12 and through which the exhaust gas passes, the rectifying cylinder 13 and the cylinder 12, And a plurality of dimple-like recesses 10A are formed on the exhaust gas contact surface of the fin 11 to increase the exhaust gas exhaust efficiency. It was possible to increase the effective power value and torque value, which could not be obtained with an exhaust structure in which irregularities were formed in the exhaust pipe. Further, the fuel efficiency is improved with the improvement of the exhaust efficiency.

  Further, the power value and torque value improved by the fins 11 having the dimple-like recesses 10A are clearly increased as compared to the tail pipe 10 having the fins 11 having no conventional recesses 10A. The power value and torque value are higher than ever obtained by mounting on an actual vehicle.

  In addition, since these effects can be obtained by attaching the tail pipe 10 to the exhaust side end portion of the vehicle muffler, the combination with the exhaust muffler already used is easy. As a result, it can be used for various exhaust mufflers used in accordance with the type of internal combustion engine such as a reciprocating engine or a hybrid engine, the vehicle type, and the like.

Further , by forming the recess 10A on one side or both sides of the fin 11, the exhaust efficiency can be adjusted according to the exhaust conditions of various exhaust mufflers.

Furthermore , if the concave portion 10A is formed on a part or the whole of the exhaust gas contact surface of the cylindrical body 12, the exhaust efficiency according to the type of the internal combustion engine and the vehicle type can be finely adjusted.

Then , by forming the recess 10A on a part or the whole of the exhaust gas contact surface of the rectifying cylinder 13, the exhaust efficiency according to the type of the internal combustion engine and the vehicle type can be further finely adjusted.

The cylindrical body 12 of the tail pipe 10 as in claim 2 has a cylindrical shape having the same diameter in the exhaust direction, a tapered shape in which the diameter in the exhaust direction is enlarged, or a reverse tapered shape in which the diameter in the exhaust direction is narrowed. Thus, the tail pipe 10 corresponding to the type of the internal combustion engine and the difference in the displacement or the size of the vehicle body can be configured.

  As described above, according to the present invention, exhaust gas exhaust efficiency can be improved, and it can be mounted on an actual vehicle to achieve more effectiveness than ever, and the type, vehicle type, and displacement of an internal combustion engine such as a reciprocating engine or a hybrid engine. The initial objectives such as being able to cope with the above were achieved.

It is a perspective view which shows the use condition of this invention. It is side sectional drawing which shows one Example of the tail pipe of this invention. It is a plane sectional view showing one example of the tail pipe of the present invention. It is a front view which shows one Example of the tail pipe of this invention. The recessed part of this invention is shown, (A) is the side view formed in the member which comprises a fin, (B) is principal part sectional drawing formed in the inner surface of an adjustment cylinder. (A) thru | or (c) are the sectional side views which showed the example of the tail pipe of this invention. It is principal part sectional drawing which shows the chamber part of the general muffler marketed.

  The basic configuration of the present invention is more than ever obtained by mounting on an actual vehicle by forming a dimple-shaped recess 10A in the fin 11 in the tail pipe 10 mounted on the exhaust side end of the exhaust muffler for a vehicle. The power value and torque value are extracted.

  The tail pipe 10 has a configuration in which a plurality of fins 11 are arranged in a spiral shape in the cylindrical body 12 in the exhaust gas discharge direction (see FIG. 4). Further, a rectifying cylinder 13 through which exhaust gas passes is provided at the center of the cylinder 12. The illustrated cylinder 12 has a double structure in which the inner cylinder 12B is disposed inside the outer cylinder 12A (see FIG. 2). The straightening cylinder 13 is provided inside the inner cylinder 12B.

  On the other hand, the fins 11 are radially arranged so as to surround the outer surface of the rectifying cylinder 13 and allow the exhaust gas to pass while turning spirally. A large number of dimple-like recesses 10 </ b> A are formed on the exhaust gas contact surface of the fin 11.

  The illustrated fin 11 is configured such that a plurality of protrusions are inserted into a notch formed on the inner surface of the cylindrical body 12 and fixed (see FIG. 5A). Further, the fin 11 may be formed integrally with the cylinder 12 and the rectifying cylinder 13.

  The concave portion 10 </ b> A provided in the fin 11 is formed on the exhaust gas contact surface of the fin 11. Therefore, the surface of the fin 11 with which the exhaust gas contacts may be different depending on the number and angle of the fins 11. In that case, the position of the concave portion 10 </ b> A formed in the fin 11 is also changed, and it may be formed on both sides in addition to any one side of the fin 11. The concave portion 10A formed on the fin 11 is formed so that one side of the fin 11 is recessed. When the concave portion 10A is formed on both surfaces of the fin 11, the thickness of the fin 11 is used to form both surfaces recessed. .

  In the present invention, the basic structure is to form the dimple-shaped recess 10A in the fin 11 at the exhaust side end of the exhaust muffler for the vehicle, but in addition to the fin 11, the rectifying cylinder 13 and the cylinder 12 are provided inside. The recess 10A may be formed.

  The rectifying cylinder 13 is disposed in the axial center portion of the tail pipe 10 and is installed in a state surrounded by the fins 11. Also in the rectifying cylinder 13, the concave portion 10 </ b> A can be formed on the surface with which the exhaust gas contacts, for example, on a part or the entire surface of the rectifying cylinder 13. Although the illustrated straightening cylinder 13 is formed separately from the fins 11, the fins 11 and the straightening cylinder 13 can be integrally formed as described above.

  On the other hand, it is possible to form the recess 10 </ b> A in the cylindrical body 12. In this case, the concave portion 10A is formed on a part or the whole of the exhaust gas contact surface of the cylindrical body 12 in accordance with the type of the internal combustion engine and the vehicle type. The cylinder 12 is prepared in various types according to the vehicle body size, displacement, etc. (see FIG. 6). This figure (a) shows a taper type with an increasing diameter in the exhaust direction, (b) shows a cylindrical type with the same diameter in the exhaust direction, and (c) shows the exhaust direction. The reverse taper type in which the diameter to reach is narrowed is shown. By selecting the tail pipe 10 from the types of these cylinders 12, it is possible to adapt to the body size and displacement of the vehicle, the type of internal combustion engine, the form of the vehicle, and the like. Further, the type of the cylindrical body 12 is not limited to the illustrated example, and may be further changed.

  The cylinder 12 shown in FIG. 2 has a double structure of an outer cylinder 12A and an inner cylinder 12B. Further, as an example of the inner cylinder 12B, an inner cylinder 12B in which a discharge cylinder 12Bb is connected to the discharge side of the adjustment cylinder 12Ba is configured (see FIG. 3).

  One adjustment cylinder 12Ba has fins 11 disposed therein (see FIGS. 3 and 4). The adjustment cylinder 12Ba is appropriately selected from a cylindrical shape having the same diameter in the exhaust direction, a tapered shape in which the diameter in the exhaust direction is enlarged, or a reverse taper shape in which the diameter in the exhaust direction is narrowed. Is. The adjustment cylinder 12Ba in the illustrated example is formed in a reverse taper shape whose diameter in the exhaust direction is narrowed (see FIGS. 2 and 3).

  A recess 10A can also be formed in the inner cylinder 12B. The position of the recess 10A can be selected from a part or the whole of the inner cylinder 12B. In the illustrated example, the recess 10A is formed in the entire adjustment cylinder 12Ba of the inner cylinder 12B (see FIG. 3). In addition, it is possible to limit the periphery of the fin 11 of the adjustment cylinder 12Ba, or to form the recess 10A up to the discharge cylinder 12Bb of the cylinder 12.

  Further, the recess 10A formed on the inner surface of the adjustment cylinder 12Ba is formed by pressing from the inner surface side of the adjustment cylinder 12Ba (see FIG. 5B), but is not limited to this forming means. It is also possible to form the recess 10A by other forming means.

  The other discharge cylinder 12Bb is formed on the final end side for discharging the exhaust gas (see FIG. 3). The illustrated discharge cylinder 12Bb has a tapered shape with an increasing diameter in the exhaust direction. In the illustrated example, the recess 10A is not formed in the discharge cylinder 12Bb, but the recess 10A can also be formed in the discharge cylinder 12Bb.

  In addition, the structure of the cylinder 12 is not restricted to the example of illustration. For example, the discharge cylinder 12Bb is omitted and only the adjustment cylinder 12Ba is used as the inner cylinder 12B, and the cylinder 12 that does not separate the outer cylinder 12A and the inner cylinder 12B can be configured.

  According to the tail pipe 10 of the present invention, the exhaust gas is discharged as follows. When the exhaust gas enters the tail pipe 10, the exhaust gas that has entered the fins 11 passes while turning spirally. At this time, centrifugal force and inertia act on the exhaust gas, and the exhaust gas is discharged while being compressed on the inner surface of the cylinder 12. Then, the pressure (atmospheric pressure) of the exhaust gas passing through the rectifying cylinder 13 becomes lower (negative pressure) than the pressure (atmospheric pressure) on the fin 11 side.

Therefore, the subsequent exhaust gas continuously fed from the engine into the tail pipe 10 is strongly sucked into the rectifying cylinder 13.
Further, the exhaust gas that has passed through the fins 11 and has been discharged outside the tail pipe 10 is rotated and diffused while being spiraled outwardly due to centrifugal force and inertia, and the pressure (in the central portion surrounded by the exhaust gas ( (Atmospheric pressure) decreases. Then, the exhaust gas discharged to the outside of the tail pipe 10 through the rectifying cylinder 13 is smoothly discharged backward so as to pull the yarn with acceleration. As a result, the subsequent exhaust gas continuously fed from the engine into the tail pipe 10 can be discharged smoothly, and the exhaust efficiency is increased.

表１は、テスト車両（トヨタ社製プリウス）の純正マフラーと、各種比較マフラーとから得られたパワーデータ及びトルクデータの比較を示している。比較マフラーは、グラスウールを使用した市販品の排気マフラーと、この市販品の排気マフラーに本発明テールパイプを装着したものである（図７参照）。すなわち、市販品の排気マフラーは、カバー体２１内に内部排気管２２を設けたチャンバー２０を備えたものである。そして、各マフラーから得られたパワーデータ及びトルクデータを示している。尚、これらの測定器として、シャーシダイナモ（ボッシュ（登録商標）ＦＬＡ２０６）を使用した。

Table 1 shows a comparison of power data and torque data obtained from a genuine muffler of a test vehicle (Toyota Prius) and various comparison mufflers. The comparative muffler is a commercially available exhaust muffler using glass wool, and the tail pipe of the present invention mounted on this commercially available exhaust muffler (see FIG. 7). That is, a commercially available exhaust muffler includes a chamber 20 in which an internal exhaust pipe 22 is provided in a cover body 21. And the power data and torque data which were obtained from each muffler are shown. As these measuring instruments, chassis dynamo (Bosch (registered trademark) FLA206) was used.

Each code | symbol of Table 1 has shown the following muffler.
Reference numeral (1) denotes a genuine muffler.
The code | symbol (2) shows the commercial muffler equipped with the tail pipe 10 without the fin 11.
The code | symbol (3) shows the commercial muffler which attached the tail pipe 10 with the fin 11. FIG.
The code | symbol (4) shows the muffler which mounted | worn with the tail pipe 10 (The dimple-shaped recessed part 10A has in the fin 11) of this invention to the commercial muffler.
(Circle 1), (Circle 2), and (Circle 3) all indicate data of each muffler, white circle numbers indicate torque data, and circle numbers indicate power data.

As is apparent from Table 1, the power value (circle 4) and torque value (open circle 4) of the muffler (4) equipped with the tail pipe of the present invention are extremely superior compared to the genuine muffler (1). Is recognized.
Furthermore, the power and torque of the present invention (4) are clearly more effective than the power and torque of the exhaust pipe muffler with tailpipe (3) provided with the conventional fin 11 without dimples.

表２は、表１の具体的数値を示している。すなわち、本発明テールパイプ使用時のパワーデータ（丸４）は146.1psとなり、純正マフラー使用時のパワーの134.9psに比べて＋11.2psものパワーの向上が認められた。一方、トルクデータでも、純正マフラー（白抜き丸１）が25.5kg/mであるのに対し、本発明（白抜き丸４）では、27.0kg/mとなり、＋1.5 kg/mといった向上が認められた。

Table 2 shows specific numerical values of Table 1. In other words, the power data (circle 4) when using the tail pipe of the present invention was 146.1 ps, and an improvement of power of +11.2 ps was recognized compared to the power of 134.9 ps when using the genuine muffler. On the other hand, in the torque data, the genuine muffler (open circle 1) is 25.5 kg / m, but in the present invention (open circle 4), it is 27.0 kg / m, which is an improvement of +1.5 kg / m. Admitted.

  As described above, the effect of improving the power value and the torque value by forming the concave portion 10A in the fin 11 in the tail pipe 10 has been clarified by experiments. It seems to take time. However, the synergistic effect of the exhaust gas passage speed and the change in the airflow generated by the recess 10A under the condition that the exhaust gas passes while spirally swirling around the fins 11 induces these effects. This is considered to be an extremely important factor.

  Each configuration of the present invention is not limited to the illustrated example. For example, in addition to the tail pipe 10 and the shape and configuration of the present invention, the shape and configuration of the fin 11 and the cylindrical body 12, or the arrangement position of the recess 10A These can be arbitrarily changed without changing the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Exhaust pipe 10 Tail pipe 10A Recess 11 Fin 12 Cylinder 12A Outer cylinder 12B Inner cylinder 12Ba Adjustment cylinder 12Bb Discharge cylinder 13 Rectification cylinder 20 Chamber 21 Cover body 22 Internal exhaust pipe

Claims (2)

In a tail pipe attached to an exhaust side end portion of an exhaust muffler for a vehicle, a cylindrical body constituting the tail pipe, a rectifying cylinder disposed at a central portion of the cylindrical body, through which exhaust gas passes, a rectifying cylindrical body and the cylindrical body a plurality of fins are provided which are disposed between, the fins together with the exhaust gas to surround the outer surface of the rectifying cylinder is arranged to pass through while swirling spirally exhaust of the fin Many or all of one or both of the gas contact surfaces, one part or all of the surface of the cylinder that contacts the exhaust gas, and part or all of the surface of the rectifying cylinder that contacts the exhaust gas A tail pipe for an exhaust muffler, characterized in that a dimple-like recess is formed.   The cylindrical body of the tail pipe is formed in a cylindrical shape having the same diameter in the exhaust direction, a tapered shape in which the diameter in the exhaust direction is enlarged, or an inverse tapered shape in which the diameter in the exhaust direction is narrowed. The tail pipe for an exhaust muffler according to 1.

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