JP2011202562A - Muffler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress an influence of exhaust gas temperature, in a muffler including an exhaust gas flow passage and a valve which are provided inside of a chamber, the valve opened/closed according to a flow rate of gas circulating in the exhaust gas flow passage.SOLUTION: This muffler A includes: a spring 11 which is attached to the rotating shaft 5b of a valve plate 5a arranged inside of the chamber 1 and composing the valve 5 and which presses the valve plate 5a in a closing direction; a cover 7 covering substantially the whole periphery of the spring 11 and a part of the rotating shaft 5b; and sound absorbing material filled into the chamber 1. The spring 11 is composed of a tension spring, and has one end connected to a lever 10 attached to the end of the rotating shaft 5b of the valve 5 and the other end connected to a locking pin 12 provided to the cover. The cover 7 is covered with the sound absorbing material in the chamber 1.

Description

  The present invention relates to a silencer having an exhaust passage provided in a chamber and a valve having a valve plate biased in a closing direction by a biasing member provided in a part of the exhaust passage. The present invention relates to a silencer which can suppress the influence of the temperature even when the internal temperature of the chamber changes and can operate the valve stably.

  There is used a silencer in which an exhaust passage through which exhaust gas exhausted from the engine is circulated is formed inside the chamber, and a valve that opens and closes according to the pressure of the exhaust gas is provided in a part of the exhaust passage. In this silencer, the valve plate constituting the valve is always urged by the spring in the direction to close the exhaust flow path, and the opening degree of the valve increases as the pressure of the exhaust gas increases. .

  For example, in the case of the silencer described in Patent Document 1, a casing having a built-in butterfly valve is disposed at the downstream end of an inner pipe communicating with two chambers partitioned inside an outer shell. The butterfly valve is fixed to a shaft, and a return spring is attached to one side of the shaft. A link is fixed to the other side of the shaft, and a rod provided with a compression spring is connected to the link. With this technology, it is possible to keep the butterfly valve closed in the low output range of the engine. When the engine output increases and the butterfly valve opening increases, the opening force of the compression spring is added to open the butterfly valve. The valve can be made easy.

  Moreover, in the case of the exhaust muffler with a built-in valve for an automobile described in Patent Document 2, a flow rate sensitive valve is provided at the downstream end of the inner pipe communicating with the two chambers partitioned inside the outer shell. The valve is attached to a plurality of support rods slidably provided on the baffle plate. Each support rod is provided with a coil spring, and the valve is urged toward the inner pipe by the action of the coil spring. It is configured to always close. With this technique, a stable valve opening / closing operation can be realized.

  In the case of the muffler for an internal combustion engine described in Patent Document 3, an on-off valve is provided on the downstream side of the partition wall that partitions the outer shell. This on-off valve is configured to include a valve body that is swingably supported around a fulcrum shaft, and an urging member that urges the valve body in a valve closing direction. In this technique, an increase in back pressure can be suppressed by opening and closing the on-off valve.

JP 09-303143 A Japanese Patent Laid-Open No. 11-022447 JP 2003-003820 A

  The inventions described in Patent Documents 1 to 3 described above have respective characteristics and can be preferably used. However, the return spring and compression spring in Patent Document 1, the coil spring in Patent Document 2, and the urging member in Patent Document 3 are all arranged in an exposed state in a chamber formed inside the outer shell. Has been. For this reason, each spring, coil spring, and biasing member are likely to be affected by high-temperature exhaust gas, and there is a possibility that the spring characteristics may change due to the influence of temperature.

  If the spring characteristics change under the influence of the temperature of the exhaust gas, there arises a problem that the control of the opening degree of the valve becomes unstable with this change.

  The objective of this invention is providing the silencer which can suppress the influence of the temperature of exhaust gas.

  In order to solve the above-described problems, a silencer according to the present invention includes a silencer provided with an exhaust flow path and a valve that opens and closes according to a flow rate of gas flowing through the exhaust flow path. An urging member that is attached to a rotating shaft of a valve plate that constitutes the valve and urges the valve plate in a closing direction, and substantially the entire circumference of the urging member and the rotating shaft. A cover covering a part and a sound absorbing material filled in the chamber are included.

  In the silencer, the biasing member is constituted by a tension spring, and one side of the tension spring is connected to a lever attached to the end of the rotating shaft of the valve, and the other side is a fulcrum provided on the cover. It is preferable that the cover is covered with a sound absorbing material inside the chamber.

  The silencer according to the present invention is provided with an exhaust passage in the chamber and a valve that opens and closes according to the flow rate of the gas flowing through the exhaust passage, and biases the valve plate of the valve in a closing direction. The entire circumference of the urging member and a part of the rotating shaft are covered with a cover, and the chamber is filled with the sound absorbing material, so that the heat insulating effect by the sound absorbing material can be exhibited. The influence of the temperature of the exhaust gas on the can be suppressed.

  In particular, the urging member is constituted by a tension spring, one side of the tension spring is connected to a lever attached to the end of the rotating shaft of the valve plate, and the other side is connected to a fulcrum provided on the cover, and the cover By covering the chamber with the sound absorbing material inside the chamber, the heat insulating effect of the sound absorbing material can be exhibited and the influence of the exhaust gas on the urging member can be suppressed.

  In addition, since the tension spring is covered with a cover, even when the chamber is filled with a sound absorbing material, a working space for the tension spring can be secured, and the valve plate opening degree can be stably controlled by the tension spring. Can do.

It is a three-view figure explaining the structure of a silencer. It is a figure explaining the structure of the principal part. (A) is the aa arrow directional view in FIG. 2, (b) is the bb arrow directional view in FIG. It is a figure explaining the state in which the valve | bulb is closed. It is a figure explaining the state which the valve opened fully.

  Hereinafter, the silencer according to the present invention will be described. The silencer according to the present invention is provided with a valve provided inside the chamber and configured to open and close according to the flow rate (pressure) of gas flowing through the exhaust passage. Then, the influence of the temperature of the gas flowing through the chamber on the urging member is suppressed, and the valve can be operated stably.

  In the present invention, the valve is provided in an exhaust passage provided in the chamber, and has a valve plate that is urged in a direction to be always closed by a urging member arranged in the chamber. Yes. And it is comprised so that the opening degree of a valve | bulb can be controlled by rotating a valve plate according to the flow volume (pressure) of the gas which distribute | circulates an exhaust flow path.

  In the silencer according to the present invention, it is not limited whether the inside of the chamber is constituted by one chamber or divided into a plurality of chambers, and any structure can be preferably applied. Is possible.

  Next, the configuration of the silencer A according to the present embodiment will be described with reference to FIGS. As shown in FIG. 1, the silencer A according to the present embodiment is configured to have one chamber without being partitioned into a plurality of chambers. The cross-sectional shape of the chamber 1 is not particularly limited, and is set to a shape that is most suitable for exhibiting a target silencing effect. In this embodiment, the chamber 1 has a substantially oval cross-sectional shape.

  Flange 1a, 1b is being fixed to the both ends of the chamber 1 by means, such as welding, respectively. An inlet pipe (not shown) for introducing gas from the engine is connected to the flange 1a on one side, and an exhaust pipe (not shown) for discharging the gas from the chamber 1 is connected to the flange 1b on the other side. An inflow pipe 2 constituting an exhaust passage is disposed on the flange 1a side of the chamber 1 and is fixed to the flange 1a. An exhaust pipe 3 is disposed on the flange 1b side and is fixed to the flange 1b. ing.

  The inflow pipe 2 and the discharge pipe 3 are arranged coaxially with each other, and an end portion 2a disposed inside the chamber 1 of the inflow pipe 2 and an end portion 3a disposed inside the chamber 1 of the discharge pipe 3 are They are arranged at a predetermined distance. The end portions 2a and 3a of both tubes 2 and 3 are connected in a substantially sealed state via a rectangular tube-shaped frame 4, whereby an inflow tube 2 and an exhaust tube 3 are connected to the inside of the chamber 1. A continuous exhaust flow path is formed. In particular, a large number of holes (not shown) are formed between the frame 4 of the discharge pipe 3 and the flange 1b.

  The end portion 2a of the inflow pipe 2 is welded with a frame member 4a having a square cross section constituting a part of the frame 4, the end on the inflow pipe 2 side closed with an end plate, and the other side open. Also, the end 3a of the discharge pipe 3 is welded with a frame member 4b having a square cross section forming a part of the frame 4, closed on the end of the discharge pipe 3 with an end plate, and opened on the other side. Yes. Then, in a state in which the open ends of both frame members 4a and 4b are butted, a band 4c is arranged around the butted portion and fastened by means such as bolts and nuts to constitute the frame 4 and An exhaust passage in which the inflow pipe 2 and the exhaust pipe 3 are continuous via the frame 4 is configured.

  A valve 5 is provided at the end 2 a of the inflow pipe 2 to open and close the opening at the end 2 a according to the flow rate (pressure) of the gas flowing into the inflow pipe 2. The valve 5 has a valve plate 5a that is closed by covering the opening at the end 2a of the inflow pipe 2 and opened by being separated from the opening.

  In this embodiment, the valve plate 5a is not designed to completely close the opening at the end 2a of the inflow pipe 2, but when it contacts the opening at the end 2a. Even so, the gap 2b through which the gas can flow is formed.

  The valve plate 5 a is fixed to a rotating shaft 5 b provided on the side portion at the opening portion of the end portion 2 a of the inflow pipe 2. The rotation shaft 5 b is rotatably supported by two bearings 5 c and 5 d attached to the frame 4, and one end portion extends through the frame 4. A cap 5e is attached to the bearing 5c, and the cap 5e maintains airtightness. Similarly, the bearing 5d is configured to maintain airtightness. Therefore, the gas flowing into the frame 4 does not leak into the chamber 1 along the rotation shaft 5b.

  A stud 6 having a preset height is disposed on the surface of the frame 4 on the side through which the rotation shaft 5 b passes, and a cover 7 is attached to the stud 6. The cover 7 includes a tray-like base 7a having standing pieces formed on the entire periphery, and a lid member 7b having hanging pieces formed on the entire periphery, and fixes the base 7a to the stud 6. By fixing the lid member 7b to the base 7a with means such as bolts and nuts, a substantially sealed space 7c can be formed.

  The planar shape and height of the space 7c formed inside the cover 7 are determined according to the size and shape of the lever 10 described later, the specifications of the spring 11, and the rotation of the lever 10 according to the rotation set in the valve plate 5a. It is appropriately set according to various conditions including the moving angle.

  One end (bearing 5d side) of the rotating shaft 5b constituting the valve 5 penetrates the frame 4 and the base 7a of the cover 7, and the end portion projects into the space 7c in a cantilever shape. And the lever 10 is being fixed to the edge part which protruded in the space 7c of the rotating shaft 5b, and the end of the spring 11 by which the other end was latched by the latching pin 12 is latched by this lever 10. .

  The spring 11 serves as an urging member that urges the valve plate 5a in contact with the opening portion at the end portion 2a of the inflow pipe 2 to close the opening portion, and has a predetermined spring characteristic. It is configured as a tension spring with The other end of the spring 11 is locked to a locking pin 12 serving as a fulcrum arranged upright at a predetermined position of the base 7a. Further, a stopper pin 13 with which the lever 10 abuts is disposed at a predetermined position of the base 7a constituting the cover 7.

  In the above-described configuration, the lever 10 is always urged clockwise by the spring 11 in FIG. 2B, and the lever 10 is rotated counterclockwise to abut against the stopper pin 13. Will be regulated by.

  As described above, the protruding end of the rotating shaft 5b, the lever 10 fixed to the protruding end, the spring 11 locked to the lever 10, the locking pin 12, and the stopper pin 13 are arranged inside the space 7c of the cover 7. It is housed in an airtight state. That is, the spring 11 is covered by the cover 7 over substantially the entire periphery. Further, the cover 7 is separated from the frame 4 by the height of the stud 6 to prevent the heat of the frame 4 from being directly transmitted to the cover 7.

  The chamber 1 is filled with a sound absorbing material (not shown). The sound-absorbing material is not particularly limited, but it is preferable that the sound-absorbing material does not deteriorate even when exposed to high temperatures and can maintain sound-absorbing performance in a stable state. As a sound absorbing material having such properties, there is glass wool having both high heat insulation properties. In this embodiment, glass wool is used as the sound absorbing material.

  The sound absorbing material is filled in the chamber 1 and is surely filled in a gap formed between the frame 4 and the cover 7. In particular, the entire periphery of the cover 7 is covered with the filled sound absorbing material, and the cover 7 is protected from the high temperature atmosphere in the chamber 1 by the heat insulating property of the filled sound absorbing material.

  In the silencer A configured as described above, the mechanism for energizing the valve plate 5a of the valve 5 is accommodated in the space 7c of the cover 7 while maintaining airtightness. For this reason, even when the chamber 1 is filled with a fibrous sound absorbing material such as glass wool, the filled sound absorbing material does not enter the space 7c of the cover 7, and the lever 10 rotates and the lever 10 rotates. There is no problem in the movement of the spring 11 such as expansion and contraction and rotation.

  As described above, since the cover 7 is separated from the frame 4 by the height of the stud 6 and the entire periphery is covered with the sound absorbing material, the high-frequency gas flowing through the exhaust passage provided in the chamber 1 is used. Can suppress the influence exerted on the spring 11 accommodated in the space 7 c of the cover 7. That is, even if the temperature of the frame 4 rises due to the heat of the gas flowing in from the inflow pipe 2, the cover 7 is separated without contacting the frame 4 directly. It becomes possible to suppress the influence. Even if heat is released from the exhaust pipe 3 into the chamber 1, the entire periphery of the cover 7 is covered with the sound absorbing material, so that the influence of the released heat is suppressed.

  Therefore, although the spring 11 whose characteristics are most sensitive to temperature is provided in the interior of the chamber 1, the thermal influence by the gas flowing through the exhaust passage provided in the chamber 1 is suppressed. As a result, stable spring characteristics can be exhibited.

  Next, the operation of the silencer A configured as described above will be described with reference to FIGS.

  As shown in FIG. 4, one end of the spring 11 whose other end is locked to the locking pin 12 is locked to the lever 10 fixed to the rotating shaft 5 b, so that the rotating shaft 5 b is connected to the spring 11. It is urged in the pulling direction (clockwise direction in FIG. 5C). Then, when the rotating shaft 5b is biased in this way, the valve plate 5a attached to the rotating shaft 5b is opened at the end portion 2a of the inflow pipe 2 as shown in FIG. And the opening is closed.

  When the valve plate 5a closes the opening portion at the end 2a of the inflow pipe 2 as described above, this closing does not completely close the opening portion, but the opening portion and the valve plate 5a are not closed. The gap 2b shown in FIGS. Accordingly, when the engine speed is small and the amount of exhaust gas is small and the pressure is smaller than the force received by the valve plate 5a from the spring 11, the valve plate 5a is open at the end 2a of the inflow pipe 2. The gas flows in from the gap 2b.

  As the engine speed increases, the flow rate of the exhaust gas increases, the pressure of the exhaust gas increases, and the force acting on the valve plate 5a along with the gas flow acts on the valve plate 5a. The valve plate 5a is separated from the opening at the end 2a of the inflow pipe 2 in accordance with the difference in force at this time. That is, as shown in FIG. 5C, the rotation shaft 5b and the lever 10 are rotated counterclockwise.

  As the exhaust gas further increases, the rotation of the lever 10 and the rotation shaft 5b stops when the rotation shaft 5b and the lever 10 rotate counterclockwise and the lever 10 comes into contact with the stopper pin 13. . That is, as shown in FIG. 5B, the valve plate 5a opens the opening portion at the end 2a of the inflow pipe 2 to the maximum extent.

  The silencer according to the present invention can be used as a silencer for automobiles and motorcycles.

A silencer 1 chamber 1a, 1b flange 2 inflow pipe 2a end 2b gap 3 discharge pipe 3a end 4 frame 4a, 4b frame member 4c band 5 valve 5a valve plate 5b rotating shaft 5c, 5d bearing 5e cap 6 stud 7 Cover 7a Base 7b Lid member 7c Space 10 Lever 11 Spring 12 Locking pin 13 Stopper pin

Claims (2)

In a silencer provided with a valve that opens and closes in accordance with the flow rate of the gas flowing through the exhaust flow channel and the exhaust flow channel inside the chamber,
An urging member disposed inside the chamber and attached to a rotation shaft of a valve plate constituting the valve to urge the valve plate in a closing direction; and substantially the entire circumference and rotation of the urging member A silencer comprising: a cover covering a part of the shaft; and a sound absorbing material filled in the chamber. The biasing member is constituted by a tension spring, one side of the tension spring is connected to a lever attached to the end of the rotation shaft of the valve plate, the other side is connected to a fulcrum provided on the cover, and The silencer according to claim 1, wherein the cover is covered with a sound absorbing material inside the chamber.

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