JP3077427U - silencer - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable a silence effect of a silencer to be adjusted in a stepless manner without attaching / detaching parts. SOLUTION: A sound absorbing chamber 3 filled with a sound absorbing material 5 is formed on an outer peripheral portion of an exhaust pipe 2 forming an exhaust flow path of an engine, and a large number of the sound absorbing chambers 3 are formed in the exhaust pipe 2. A silencer 1 for introducing engine exhaust through a communication hole 2a. The silencer 1 has an adjustment hole 6a corresponding to the position of the communication hole 2a, and is slidably mounted on the exhaust pipe 2. Inner pipe 6
And the noise reduction effect is adjusted based on a change in the overlapping area between the communication hole 2a and the adjustment hole 6a accompanying the sliding operation of the inner pipe 6.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a silencer provided in an engine exhaust path of an automobile, a motorcycle and the like to muffle engine exhaust sound, and more particularly to a silencer capable of adjusting a muffling effect.

[0002]

[Prior art]

 Generally, in this type of silencer (muffler), a sound absorbing chamber filled with a sound absorbing material such as glass wool is formed on an outer peripheral portion of an exhaust pipe forming an exhaust flow path of an engine. There is one configured to muffle engine exhaust noise by introducing engine exhaust through a large number of communication holes formed in an exhaust pipe.

[0003] In the above-described silencer, the silencing effect (silencing performance) depends on the communication area between the exhaust pipe and the sound absorbing chamber, the volume of the sound absorbing chamber, the type of the sound absorbing material, the degree of packing of the sound absorbing material, and the like. It is known that it changes, so it is relatively easy to increase the noise reduction effect. However, increasing the noise reduction effect increases exhaust resistance (back pressure) and conversely decreases engine output. There is inconvenience to do. Therefore, in the conventional silencer, the noise reduction effect is set in consideration of the balance with the engine output, and each part is designed to exhibit the noise reduction effect.

[0004] However, the balance between the muffling effect and the engine output set as described above is compromised in consideration of various use situations, and is not always optimal in each use situation. It is not possible to respond to situations where, for example, there is a situation in which it is desired to increase the engine output while minimizing the muffling effect, or a situation in which it is desired to increase the muffling effect even at the expense of the engine output. Was.

[0005] Therefore, as shown in FIG. 4, it has been proposed that an inner pipe is inserted into an exhaust pipe and the communication hole is closed with the inner pipe to change the noise reduction effect. Had the following problems. (1) Two-stage adjustment (inner pipe mounted state and non-mounted state), and the muffling effect cannot be adjusted according to various usage conditions. (2) The inner pipe needs to be attached and detached, and the adjustment work is troublesome. (3) The inner pipe cannot be removed in a high temperature state immediately after the engine is stopped. (4) Hands and clothes become dirty with carbon or the like attached to the inner pipe. (5) A place for storing the removed inner pipe is required.

[0006]

[Problems to be solved by the invention]

 The present invention was conceived to eliminate the above-mentioned problems, and the noise reduction effect can be adjusted in a stepless manner, whereby the balance between the noise reduction effect and the engine output can be variously used. It also makes adjustment work easier by eliminating the need for attaching and detaching the inner pipe, making adjustment work possible even at high temperatures immediately after the engine is stopped. It is an object of the present invention to provide a silencer that can eliminate the inconvenience of soiling clothes and clothes, and can also make the storage space for the inner pipe unnecessary.

[0007]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention forms a sound absorbing chamber filled with a sound absorbing material on an outer peripheral portion of an exhaust pipe forming an exhaust passage of an engine, and has a large number of sound absorbing chambers in the sound absorbing chamber. A silencer for introducing engine exhaust through a communication hole formed, the silencer having an adjustment hole formed corresponding to the communication hole position, and slidably inserted into the exhaust pipe. By providing an inner pipe to be installed, a noise reduction effect can be adjusted based on a change in the overlapping area between the communication hole and the adjustment hole due to a sliding operation of the inner pipe. Things.

[0008]

[Embodiment of the invention]

 Hereinafter, an embodiment of the present invention will be described in detail based on a silencer exemplified as a preferred embodiment. FIG. 1 is an exploded perspective view of a silencer according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of the silencer, (A) is a horizontal cross-sectional view, and (B) is a vertical cross-sectional view.

As shown in FIGS. 1 and 2, a silencer 1 according to this embodiment forms an exhaust pipe 2 forming an exhaust flow path of an engine, and a sound absorbing chamber 3 on an outer peripheral portion of the exhaust pipe 2. A drum 4 and a sound absorbing material 5 such as glass wool or stainless steel wool filled in the sound absorbing chamber 3 are provided. A large number of communication holes 2a of a predetermined shape are formed in the exhaust pipe 2 in a predetermined arrangement, and the engine exhaust sound is muted by introducing engine exhaust into the sound absorbing chamber 3 through the communication holes 2a. Have been.

The communication holes 2a are usually circular, and are formed in the exhaust pipe 2 so as to be arranged in a staggered manner (the rows of adjacent holes are arranged half pitch apart from each other). The shape may be an ellipse, an ellipse, a square, an oblong square, etc. other than a circle, and the arrangement can be set arbitrarily (the illustrated one is an ellipse).

The total opening area of the communication hole 2a is one factor that determines the silencing effect of the silencer 1, and is set in consideration of the balance with the engine output. That is, in general, the total opening area of the communication hole 2a is determined in consideration of various usage conditions so as to exhibit a noise reduction effect suitable for a standard usage condition. In the silencer 1 of the present embodiment that adjusts the noise reduction effect based on the change in the opening area of the communication hole 2a, it is desirable to increase the total opening area of the communication hole 2a in advance, and thereby the adjustment range of the noise reduction effect. Can be expanded.

As shown in FIG. 2, the exhaust pipe 2 is provided with an inner pipe 6 having a number of adjusting holes 6a. The outer diameter of the inner pipe 6 is set slightly smaller than the inner diameter of the exhaust pipe 2, and sliding in the circumferential direction in the exhaust pipe 2 is allowed. The adjusting hole 6a is formed corresponding to the communicating hole 2a of the exhaust pipe 2. In the present embodiment, the adjusting hole 6a is formed so that the shape and the arrangement match the communicating hole 2a. I have. When the inner pipe 6 is slid, the overlapping area between the communication hole 2a of the exhaust pipe 2 and the adjustment hole 6a of the inner pipe 6, that is, the effective total opening area of the communication hole 2a changes steplessly. The silencing effect of the silencer 1 is adjusted based on the change in the opening area.

A slot 2b extending in the circumferential direction is formed at the end of the exhaust pipe 2, while a screw hole 6b is formed at the end of the inner pipe 6 corresponding to the position of the slot 2b. A screw 7 is screwed into the screw hole 6b via the long hole 2b. That is, the inner pipe 6 is fixed to the exhaust pipe 2 by tightening the screw 7, and when the screw 7 is loosened, the inner pipe 6 is slidably guided in the circumferential direction by the guide action of the elongated hole 2b. In addition, in the sliding guide range of the inner pipe 6 by the elongated hole 2b, the position of the adjustment hole 6a and the communication hole 2a coincide with each other, and the fully opened adjustment position for fully opening the communication hole 2a; And a fully closed adjustment position for completely closing the communication hole 2a without any overlap between the communication hole 2a and the communication hole 2a.

In the embodiment of the present invention configured as described above, the silencer 1 has an adjustment hole 6a corresponding to the position of the communication hole 2a formed in the exhaust pipe 2, and the exhaust pipe 2 An inner pipe 6 is provided so as to be slidable inside, and the noise reduction effect is adjusted based on a change in the overlapping area between the communication hole 2a and the adjustment hole 6a accompanying the sliding operation of the inner pipe 6. It is configured. This effect will be described with reference to FIG. 3 (FIG. 3 shows a circular hole). In order to adjust the noise reduction effect, after loosening the screw 7, the inner pipe 6 is slid in the circumferential direction, and, for example, as shown in FIG. When the moving operation is performed, the positions of the adjusting hole 6a and the communication hole 2a coincide with each other, so that the communication hole 2a is fully opened, and the silencer 1 exhibits the maximum noise reduction effect, while the exhaust resistance by the silencer 1 also increases. And the engine output will decrease.

Further, as shown in FIG. 3B, when the inner pipe 6 is slid to the half-open adjustment position, almost half of the adjustment hole 6a overlaps with the communication hole 2a. Is in a half-open state, and the silencer 1 exhibits approximately half the silencing effect as compared to when it is fully open, while the exhaust resistance of the silencer 1 is also approximately half and the engine output is higher than when it is fully open.

Further, as shown in FIG. 3 (C), when the inner pipe 6 is slid to the fully closed adjustment position, the adjustment hole 6a and the communication hole 2a do not overlap at all, so that the communication hole 2a Is completely closed, and the silencing effect of the silencer 1 is lost, while the exhaust resistance of the silencer 1 is minimized, and the engine output is greatly increased.

In this state, it is desirable to set the vehicle so as to be suitable for vehicle inspection.

Accordingly, the silencing effect can be adjusted steplessly in accordance with the sliding operation of the communication hole 2a from the fully opened state to the fully closed state, whereby the balance between the silencing effect and the engine output can be varied. It can be adapted to various usage situations. In addition, since it is not necessary to attach or detach the inner pipe 6 when adjusting the noise reduction effect, the adjustment work cannot be facilitated, and the adjustment work can be performed even in a high temperature state immediately after the engine is stopped. The inconvenience that hands and clothes are stained by carbon or the like attached to the pipe 6 can be eliminated, and the storage space for the inner pipe 6 can be eliminated.

Further, since the sliding operation range of the inner pipe 6 includes a position where the communication hole 2a is changed from the fully opened state to the fully closed state, the adjustment range of the noise reduction effect by the inner pipe 6 is widened. In addition, the silencer 1 to which the inner pipe 6 is retrofitted has an advantage that the original silencing effect can be reproduced without removing the inner pipe 6.

Further, a slot 2b is formed in the exhaust pipe 2 in the sliding operation direction of the inner pipe 6, and a screw 7 is screwed into the inner pipe 6 through the slot 2b. Since the inner pipe 6 is fixed to the exhaust pipe 2 by tightening the screw 7, when the screw 7 is loosened, the inner pipe 6 can be slid and guided by the guide action of the elongated hole 2b. As a result, the fixing means and the guide means for the inner pipe 6 can be simply configured with a minimum number of parts.

The present invention is, of course, not limited to the embodiment described above. For example, the sliding direction of the inner pipe is not limited to the circumferential direction of the exhaust pipe, but may be the length of the exhaust pipe. It may be set in a direction, an oblique direction, or the like. Also, the shape and arrangement of the adjustment holes do not necessarily have to match the communication holes of the exhaust pipe.For example, the shape of the adjustment holes is not limited to a circle, but may be elliptical, elliptical, square, rectangular, etc. The arrangement can also be set arbitrarily. For example, adjustment holes can be randomly arranged to provide a general-purpose retrofit inner pipe. Further, the fixing position of the inner pipe by the screw is not limited to the end side of the exhaust pipe, but may be fixed at the starting end side or at both sides. Further, the opening area may be adjusted not for all the communication holes but for some of the communication holes.

[0022]

[Effect of the invention]

 According to the present invention, a sound absorbing chamber 3 filled with a sound absorbing material 5 is formed on an outer peripheral portion of an exhaust pipe 2 forming an exhaust passage of an engine, and a plurality of the sound absorbing chambers 3 are formed in the exhaust pipe 2. A silencer 1 that introduces engine exhaust through a communication hole 2a that has an adjusting hole 6a that is drilled corresponding to the position of the communication hole 2a. By providing the inner pipe 6 that is movably mounted, the noise reduction effect can be adjusted based on the change in the overlapping area between the communication hole 2a and the adjustment hole 6a due to the sliding operation of the inner pipe 6. This makes it possible to adjust the muffling effect in a stepless manner, thereby making it possible to adjust the balance between the muffling effect and the engine output to various use situations. This makes adjustment work easier by eliminating the need for attachment and detachment, makes adjustment work possible even in the high-temperature state immediately after the engine is stopped, and eliminates the inconvenience of dirtying hands and clothes with the carbon or the like attached to the inner pipe 6. The storage location of the pipe 6 can also be made unnecessary.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a silencer.

2A and 2B are cross-sectional views of a silencer, wherein FIG. 2A is a cross-sectional view and FIG.

3A and 3B are diagrams for explaining the operation of the silencer according to the present embodiment, wherein FIG. 3A is an enlarged view of a main part showing a communication hole fully opened state, and FIG. 3B is an enlarged view of a main part showing a communication hole half open state. ,
(C) is a principal part enlarged view which shows the communication hole fully closed state.

FIG. 4 is an exploded perspective view of a silencer showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Silencer 2 Exhaust pipe 2a Communication hole 2b Slot 3 Sound absorption room 4 Drum 5 Sound absorbing material 6 Inner pipe 6a Adjustment hole 6b Screw hole 7 Screw

Claims (3)

[Utility model registration claims] 1. A sound absorbing chamber filled with a sound absorbing material is formed at an outer peripheral portion of an exhaust pipe forming an exhaust passage of an engine, and a plurality of communication holes formed in the exhaust pipe are formed in the sound absorbing chamber. A silencer for introducing engine exhaust through the exhaust pipe, the silencer having an adjustment hole formed corresponding to the communication hole position, and an inner pipe slidably provided in the exhaust pipe. A silencer characterized in that a silencing effect can be adjusted based on a change in an overlapping area between the communication hole and the adjustment hole due to a sliding operation of the inner pipe. 2. The silencer according to claim 1, wherein the sliding operation range of the inner pipe includes a position where the communication hole is changed from a substantially fully opened state to a fully closed state. 3. An exhaust hole is formed in the exhaust pipe so that sliding of the inner pipe can be operated in a circumferential direction, and a screw is screwed into the inner pipe through the elongated hole. 3. The silencer according to claim 1, wherein the silencer is fixed to the exhaust pipe by tightening a screw.