JP2010255519A - Muffler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve an engine output by reducing the flowing resistance of exhaust gas flowing in a muffler body when an operating valve is opened, in a muffler including the operating valve opening and closing an opening of a separator partitioning the muffler body into one side and the other side. <P>SOLUTION: The operating valve V for opening and closing the opening of the separator is provided in the opening 44 of the separator 14 partitioning the inside of the muffler body 1 into a silencing chamber 21R at one side and the other side. When the operating valve V is opened, the exhaust gas flowing from the one side to the other side is discharged to the outside of the silencing chamber 21R not through the silencing chamber 21R. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an exhaust silencer connected to an exhaust system of an engine for vehicles or the like, and in particular, an exhaust gas flow resistance when an on-off valve that communicates and blocks an opening formed in a partition wall that partitions a silencer chamber is opened. The present invention relates to an exhaust silencer that reduces engine noise and improves engine output.

  2. Description of the Related Art Conventionally, a silencer in which an opening is formed in the partition wall 5 that partitions the silencing chamber, and exhaust gas is discharged out of the silencing chamber through the silencing chamber when the opening / closing valve V that opens and closes the opening is opened. Is known (see Patent Document 1 below).

JP 2008-140101 A

  However, as disclosed in Patent Document 1, when the opening / closing valve V that opens and closes the opening of the partition wall 5 is opened, the exhaust gas flows into the silencer chamber and expands. 2. Since the gas travels while colliding with the end plate 3, the partition wall 5 and the like and collides with the reflected wave, the flow of the exhaust gas is disturbed, and the flow resistance of the exhaust gas is increased by the amount of the disturbance. There is a problem that this causes a deterioration in the engine output improvement effect.

  The present invention has been made in view of the above circumstances, and provides a novel silencer that prevents an increase in the flow resistance of exhaust gas when the on-off valve is opened, and that can solve the above problem. With the goal.

  In order to achieve the above object, the invention according to claim 1 is provided in a silencer body, and is formed on at least one side of the separator that partitions the inside of the silencer body into one side and the other side. A silencer, comprising: an opening formed in the separator; an opening / closing valve that opens and closes the opening; and a silencer in which exhaust gas flows from the other side of the separator to one side when the opening / closing valve is opened. An exhaust passage connected to the opening is formed, and when the on-off valve is opened, exhaust gas flowing from the one side to the other side is discharged out of the muffler chamber through the exhaust passage. It is a feature.

  According to the first aspect of the present invention, when the on-off valve that opens and closes the opening of the separator is opened, the exhaust gas can be discharged outside the silencing chamber without being expanded in the silencing chamber formed on one side of the separator. Disturbances due to the expansion of the exhaust gas are suppressed, an increase in exhaust gas flow resistance when the on-off valve is opened can be prevented, and the engine output can be improved.

Overall plan view of an exhaust system of a vehicle engine equipped with the exhaust silencer of the present invention Broken perspective view of the silencer shown in the arrow 2 in FIG. Sectional view of arrow 3 in FIG. Sectional view along line 4-4 in FIG. Enlarged sectional view taken along line 5-5 in FIG. Sectional drawing which follows the 6-6 line of FIG.

  Embodiments of the present invention will be described below based on the embodiments of the present invention shown in the accompanying drawings.

  In this embodiment, the silencer of the present invention is applied to an exhaust system of a V-type engine for a vehicle. In the following description, front and rear, left and right, and top and bottom are based on the forward direction of the vehicle.

  In FIG. 1, the vehicular engine generally indicated by the symbol E is a V-type multi-cylinder engine, and includes left and right banks BL and BR that form a pair, and the exhaust manifolds of these banks BL and BR include The first exhaust pipe P1 and the second exhaust pipe P2 are connected to each other. The first and second exhaust pipes P1 and P2 are separated from each other in the width direction of the vehicle body F and extend in the front-rear direction. The exhaust pipes P1 and P2 are primary in order from the upstream side to the downstream side. The catalyst CA1, the secondary catalyst CA2, and the auxiliary silencer (prechamber) PC are connected in series. The silencers M according to the present invention are connected in parallel to the downstream ends of the first and second exhaust pipes P1 and P2 through joints J and J, respectively. The auxiliary silencers PC and PC are connected to each other to regulate the distance between them, and the downstream side of the auxiliary silencers PC and PC of the first and second exhaust pipes P1 and P2 is an elastic support member. The silencer M is suspended and supported by the vehicle body F via the other elastic support members S2 and S2 and is suspended and supported by the vehicle body F via S1 and S1.

  The exhaust gas discharged from the operation of the engine E is purified by the primary and secondary catalytic converters CA1 and CA2 to remove harmful components such as HC, CO and NOx, and then the auxiliary silencer. After being silently silenced through the PC, the sound is silenced by the silencer M and discharged to the outside.

  Next, the configuration of the exhaust silencer according to the present invention will be described in detail with reference to FIGS.

  The silencer M is disposed in such a direction that its longitudinal center axis LL crosses the longitudinal direction of the vehicle body F, and the silencer body 1 that forms the main part of the silencer M and the exhaust gas from the engine E are silenced. A pair of left and right first exhaust gas introduction pipes 2L and second exhaust gas introduction pipes 2R that lead to the main body 1 and a pair of left and right exhausts that exhaust the exhaust gases in the expansion chambers 20, 21, and 21 of the silencer main body 1 to the outside. Exhaust gas discharge pipes 5 and 5 are provided.

  The silencer body 1 constitutes the housing of the silencer M, and includes a cylindrical shell 10 whose left and right end faces are open, a left end wall 11 that is airtightly fixed to the left opening end of the shell 10, and the shell. A right end wall 12 that is airtightly fixed to the right opening end of the right side wall and a cylindrical shape that is more hermetically sealed, and a sound deadening chamber is formed therein. The silencer body 1 is supported by the vehicle body F with its longitudinal center axis LL directed in the left-right direction.

  A pair of left and right inner separators 13, 13 each having a plurality of small holes 15 made of punching holes are fixed substantially parallel to the left and right end walls 11, 12 at the central portion in the longitudinal direction of the inner surface of the silencer body 1. An expansion chamber 20 is formed between the pair of inner separators 13 and 13. A pair of left and right outer separators 14 and 14 are fixed to the left and right end walls 11 and 12 in the longitudinal direction of the inner surface of the silencer body 1 so as to be substantially parallel to the left and right end walls 11 and 12. And expansion chambers 21 and 21 are formed between the inner separators 13 and 13 and the outer separators 14 and 14, and between the outer separator 14 and the left end wall 11 and between the outer separator 14 and the right end wall 12. The resonance chambers 21R are respectively formed.

  A pair of left and right first exhaust gas introduction pipes 2 </ b> L and a second exhaust gas introduction pipe 2 </ b> R are provided in the shell 10 so as to be biased closer to the left and right end walls 11, 12 than the longitudinal center of the sound deadening chamber body 1. Each is through-connected. The upstream end of the first exhaust gas introduction pipe 2L and the upstream end of the second exhaust gas introduction pipe 2R are connected to the downstream end of the first exhaust pipe P1 and the second exhaust pipe P2 outside the silencer body 1. The first exhaust gas introduction pipe 2L and the second exhaust gas introduction pipe 2R are connected to the downstream ends via joints J and J, respectively, in the expansion chambers 21 and 21 of the silencer main body 1. One branch pipe 3, 3 and the other branch pipe 4, 4 are bifurcated. One branch pipe 3, 3 extends toward the center in the silencer main body 1, and its downstream end is penetrated and supported by the central part of the inner separators 13, 13, and the central part of the expansion chamber 20, That is, the silencer body 1 is opened on the longitudinal center axis LL. As shown in FIGS. 2 and 3, the downstream end openings of the pair of left and right one branch pipes 3 and 3 are arranged to face each other with a space in the central portion in the expansion chamber 21. On the other hand, the pair of left and right other branch pipes 4, 4 extend in the silencer body 1 toward the left and right end walls 11, 12, respectively, and their downstream ends are biased in the radial direction of the outer separators 14, 14. And is communicated with an inlet of an on-off valve V described later.

  A pair of left and right exhausts penetrating the resonance chamber 21R is provided between the pair of left and right outer separators 14 and 14 and the left and right end walls 11 and 12 at positions that are separated from the on-off valve V and are radially offset. Gas exhaust pipes 5 and 5 are respectively supported along the axial direction of the silencer body 1, and the upstream ends of the exhaust gas exhaust pipes 5 and 5 are expanded in a divergent shape so that the inner and outer separators 13, Opened into the expansion chambers 21 and 21 between the 13, 14, and 14 and the downstream ends thereof are connected to tail pipes 23 and 23 that open to the outside, respectively.

  A pair of left and right outer separators 14 and 14 are supported by a pair of communicating pipes 16 and 17, respectively. The communicating pipes 16 and 17 have an expansion chamber 21 between the inner and outer separators 13 and 14, and a resonance chamber 21R. And communicate with each other.

  The pair of left and right inner separators 13 and 13 and the pair of left and right outer separators 14 and 14 are respectively connected by a plurality of (three) connecting rods 18 that are fixed to their outer peripheral portions with a circumferential interval therebetween. Yes.

  As shown in FIG. 3, the on-off valve V includes a housing 30 supported between outer separators 14 and 14 and left and right end walls 11 and 12, a valve body 31 provided in the housing 30, and a valve body. And a valve spring 32 formed of a coil spring that elastically biases 31 to a closed position. The on-off valve V communicates with the downstream opening of the other branch pipe 4 whose inlet is connected to the opening 44 formed in the outer separator 14, and its outlet opens to the outside via the exhaust passage 33. Connected to the tail pipe 24. When the exhaust gas pressure in the first and second exhaust gas introduction pipes 2L, 2R is equal to or lower than a predetermined value, the valve body 31 closes the downstream opening of the other branch pipe 4 by the elastic force of the valve spring 32. When the other branch pipe 4 and the outside are maintained in a shut-off state, and when the exhaust gas pressure in the first and second exhaust gas introduction pipes 2L and 2R exceeds a predetermined value, the valve body 31 is closed. Is opened against the elastic force of the valve spring 32, and the downstream opening of the other branch pipe 4 is opened to the outside through the exhaust passage 33 without communicating with the resonance chamber 21R.

  In FIG. 1, reference numeral 25 denotes a side branch (resonance silencer) connected in the middle of the tail pipe 23.

  Next, the operation of this embodiment will be described.

  Now, according to the operation of the V-type engine E, the exhaust gas discharged from the left and right banks BL, BR flows through the first exhaust pipe P1 and the second exhaust pipe P2, and passes through the primary and secondary catalysts CA1, CA2, respectively. After flowing and purifying harmful components such as Nx, CO, and HC, they enter the prechambers PC and PC, where they are primarily silenced, and then pass through the first exhaust gas introduction pipe 2L and the second exhaust gas introduction pipe 2R. It is guided to the silencer M according to the present invention, and after being silenced as described later, it is discharged to the outside.

  In the low speed operation region including the idling operation and the start operation of the engine E, the combustion pressure of the engine E is low and the pressure of the exhaust gas discharged from the engine E is also low. Therefore, the first exhaust gas introduction pipe 2L and the second exhaust gas Since the pressure of the exhaust gas flowing into the silencer body 1 from the introduction pipe 2R is weaker than the resilience of the valve spring 32 of the on-off valve V, the valve body 32 of the on-off valve V is as shown by the solid line position in FIG. The closed state is maintained. Therefore, the exhaust gas introduced into the first and second exhaust gas introduction pipes 2L and 2R expands through the one of the left and right branch pipes 3 and 3 as shown by the solid line arrow a in FIG. The left and right inner separators 13 and 13 pass through the small holes 15 and then divert to the left and right expansion chambers 21 and 21. Through the exhaust gas discharge pipes 5 and 5.

  In this process, the exhaust sound of the exhaust gas is effectively silenced by the silencing effect due to expansion in the expansion chambers 20, 21, and 21 and the silencing effect due to resonance in the resonance chambers 21R and 21R.

  By the way, in the low-speed operation region of the engine E, the exhaust gas introduced into the first and second exhaust gas introduction pipes 2L and 2R passes through the one of the left and right branch pipes 3 and 3, and the expansion chamber 20 Since the amount of exhaust gas flowing into the expansion chamber 20 increases, the downstream end openings of the left and right branch pipes 3 and 3 face each other in the expansion chamber 20. Therefore, the amount of exhaust gas involved in interference increases as much as possible, and the amount of interference of exhaust gas also increases. As a result, the silencing effect based on the interference of exhaust gas is greatly enhanced.

  In particular, as shown in FIGS. 2 and 3, the downstream end opening of one branch pipe 3 of the first exhaust gas introduction pipe 2L and the downstream of one branch pipe 3 of the second exhaust gas introduction pipe 2R. The side end openings are on the longitudinal center axis LL of the silencer M main body, and are opposed to each other with a space at the center of the expansion chamber 20, so that the exhaust gas after interference is made. It can be expanded uniformly in the expansion chamber 20, and the silencing effect due to the expansion of the exhaust gas can be enhanced.

  On the other hand, when the combustion of the engine E is in a complete explosion state and reaches the high speed operation region, the combustion pressure increases, and the pressure of the exhaust gas exhausted therefrom increases, so the first exhaust gas introduction pipe 2L The pressure of the exhaust gas flowing into the second exhaust gas introduction pipe 2R also increases, and the pressure of the exhaust gas flowing into the other branch pipes 4, 4 is greater than the spring force of the valve spring 32 of the on-off valve V. The valve body 31 of the on-off valve V is opened as shown by the chain line in FIG. Therefore, most of the exhaust gas flowing into the first exhaust gas introduction pipe 2L and the second exhaust gas introduction pipe 2R does not pass through the expansion chambers 20, 21, 21, and the other branch pipes 4, 4 The exhaust gas is directly discharged to the outside through the on-off valve V and the exhaust passage 33, and the flow resistance of the exhaust gas is greatly reduced.

  The first and second exhaust gas introduction pipes 2L and 2R pass through the shell 10 between the left and right end walls 11 and 12, and are connected to the silencer main body 1. The exhaust gas introduction pipes 2L and 2R Since the other branch pipes 4 and 4 on the side where the on-off valves V and V are provided open directly from the left and right end walls 11 and 12 to the outside of the silencer body 1, when the on-off valves V and V are opened, The pipe length until the exhaust gas in the first and second exhaust gas introduction pipes 2L and 2R reaches the external opening of the silencer body 1 via the other branch pipes 4 and 4 is shortened, and the exhaust gas flow resistance is reduced. Furthermore, by reducing the flow resistance to the external opening when the on-off valves V, V are opened, the expansion chambers 20, 21, 21 can be opened when the on-off valves V, V are opened. Directly discharged from the external opening through the other branch pipes 4 and 4 without going through The amount of exhaust gas generated increases, and the amount of exhaust gas flowing into the expansion chambers 20, 21, and 21 via the one branch pipes 3, 3 that do not have the on-off valves V, V decreases. An increase in distribution resistance due to discharge via 20, 21, 21 can be greatly reduced. As a result, as a whole, the flow resistance of the exhaust gas flowing through the silencer body 1 can be reduced as much as possible, thereby enhancing the output improvement effect of the engine.

  As mentioned above, although the Example of this invention was described, this invention is not limited to the Example, A various Example is possible within the scope of the present invention.

  For example, in the above-described embodiment, the case where the silencer M of the present invention is implemented in the exhaust system of the V-type engine E for vehicles has been described, but it can be applied to the exhaust system of engines for other purposes such as general purpose. It is.

  Further, in the above-described embodiment, the resonance chambers 21 </ b> R as the sound deadening chambers are formed between the outer separator 14 and the left end wall 11 and between the outer separator 14 and the right end wall 12. The silencing chamber formed between the left end wall 11 and between the outer separator 14 and the right end wall 12 may be an expansion chamber, and the silencing chamber in the claims is expanded when it is a resonance chamber. Including both the case of the room.

1 ... silencer body 14 ... separator (outside separator)
21R ... Silencer room (resonance room)
33 ... Exhaust passage 44 ... Open V ... Open / close valve

Claims (1)

A separator (14) provided in the silencer body (1) and partitioning the silencer body (1) into one side and the other side, and a silencer chamber formed on at least one side of the separator (14) (21R), an opening (44) formed in the separator (14), and an on-off valve (V) for opening and closing the opening (44). When the on-off valve (V) is opened, the separator (14) In silencers where exhaust gas flows from one side to the other,
An exhaust passage (33) connected to the opening (44) is formed in the silencer chamber (21R), and the exhaust gas flowing from the one side to the other side when the on-off valve (V) is opened is A muffler, characterized in that it is discharged out of the muffler chamber (21R) through an exhaust passage (33).

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