JP3982677B2 - Exhaust control valve device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an exhaust control valve device interposed in an exhaust passage of a four-cycle engine.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, for example, as an exhaust device for a motorcycle four-cycle engine, exhaust pipes for each cylinder extending from the engine are arranged in the vehicle width direction below the engine, and one exhaust control valve device is interposed in the middle of these exhaust pipes. There is a disguise. In this exhaust control valve device, the exhaust pipe is connected to a front end portion of a valve housing formed in a box shape that is long in the vehicle width direction, and a rotary valve body is provided inside the valve housing. It is provided so as to be rotatable in a state of directing the direction.
[0003]
The valve body is configured by a plate-like portion that extends in the vehicle width direction and faces the downstream side opening of all exhaust pipes, and shaft portions provided at both ends of the plate-like portion. The valve housing is rotatably supported. The plate-like portion is formed in a circular arc shape so as to follow a circle centering on the shaft portion when viewed from the axial direction of the valve body, and a closed position facing the opening, and the opening faces rearward. It rotates between the open position on the upper side opened.
[0004]
When the valve body formed in this way is closed, the pressure wave of the exhaust gas propagating in the exhaust pipe is reflected mainly in the vicinity of the opening, and when the valve body is opened, the pressure wave is mainly behind the valve housing. Reflect on the wall. The opening and closing of the valve body is set to close at low speed and open at high speed so that a negative pressure wave reaches the exhaust port when the engine exhaust port opens at both low and high speeds. ing.
[0005]
However, since the conventional exhaust control valve device configured as described above rotates upward from the exhaust pipe when the valve element opens, a valve element accommodating space is provided above the valve housing so that the valve element can be accommodated. There has been a problem that the valve housing becomes large.
The inventors have considered reducing the size of the apparatus by using a butterfly type exhaust control valve instead of the so-called rotary type gate valve as described above. That is, by arranging exhaust passages in the valve housing in parallel and providing a butterfly-type exhaust control valve so as to cross these exhaust passages, it is not necessary to form a space that protrudes greatly outside the exhaust passage. The valve housing preferably has a structure in which the exhaust control valve is assembled in the axial direction in order to achieve miniaturization.
[0006]
[Problems to be solved by the invention]
However, if a single butterfly-type exhaust control valve is used to open and close a plurality of exhaust passages, when the exhaust control valves are assembled in the valve housing along the axial direction, adjacent exhaust passages are defined. A hole for inserting the plate-like valve element into the partition wall must be formed so as to allow the valve element to rotate, and a new problem arises in that a pressure wave leaks from this hole to the adjacent exhaust passage.
[0007]
Such a problem can be solved by providing the valve body with a partition plate that closes the hole, that is, a partition plate having the same diameter as the maximum outer diameter of the plate-like valve body. However, for example, when a structure in which two exhaust passages are opened and closed by one exhaust control valve, the pressure of exhaust gas is applied to one partition plate provided between both exhaust passages, and this partition plate is connected to one and the other. Will be repeatedly pressed. When the partition plate is pressed in this manner, there is a problem that the exhaust control valve repeatedly collides with the valve housing, and a hitting sound is generated from the collision portion.
[0008]
More specifically, the pressures of two exhaust passages connected to different cylinders do not increase or decrease at the same timing, and when the pressure of one exhaust passage is high, the pressure of the other exhaust passage is low. Since such pressure fluctuations are alternately repeated during engine operation, the exhaust control valve is alternately urged in one of the axial directions and the other, and the hitting sound is repeatedly generated. It is conceivable to provide a partition plate at both ends of the exhaust control valve to offset the pressure difference, but it is necessary to insert a partition plate of the same size as the valve body through the inner wall of the exhaust passage. The assembly work of the valve becomes extremely complicated.
[0009]
The present invention was made to solve such problems, and while using a butterfly-type exhaust control valve, there is no pressure wave leakage or sound generation, and exhaust control is easy to assemble. An object is to provide a valve device.
[0010]
[Means for Solving the Problems]
In order to achieve this object, an exhaust control valve device according to the present invention has a butterfly type exhaust control valve in which at least two exhaust passages are arranged in parallel in a valve housing, and the parallel direction of these exhaust passages is an axial direction. The exhaust control valve device is provided so as to be rotatable, the valve housing has a structure in which the exhaust control valve is incorporated in the axial direction, and the exhaust control valve is provided for each valve passage and each exhaust passage provided in the valve shaft. A plate-like valve body, and a plurality of pressure-receiving plates provided between the plate-like valve bodies and at both ends of the exhaust control valve so as to constitute a part of the inner wall of each exhaust passage. Is a disc shape along a plane orthogonal to the axis of the valve shaft, and has an outer diameter larger than the shaft diameter of the portion where the plate valve body is provided and an outer diameter larger than the maximum outer diameter of the plate valve body. The valve housing A partition wall for defining the definitive exhaust passage with each other, in which the pressure receiving plate and the plate valve body to form a notch that can be inserted.
[0011]
According to the present invention, the pressure of each exhaust passage applied to the exhaust control valve is canceled by the pressure receiving plate. In this pressure receiving plate, a plate-like valve body is formed for each exhaust passage, and it is not necessary to form a large hole in the partition wall so that the plate-like valve body can rotate. It can be made small so that it can be attached. The notch formed in the partition wall can be formed in substantially the same shape as the plate-like valve body and the pressure receiving plate when viewed from the axial direction, and the portion of the notch through which the pressure receiving plate passes is during operation. Closed by the pressure plate.
[0012]
An exhaust control valve device according to a second aspect of the present invention is the exhaust control valve device according to the first aspect of the present invention, wherein the outer diameters of the three pressure receiving plates of the exhaust control valve are made to coincide with each other. .
According to the present invention, the pressure of the exhaust passage similarly acts on the two pressure receiving plates for each exhaust passage, so that the force that urges the exhaust control valve in the axial direction even if the pressure of the two exhaust passages changes alternately. Will not occur.
[0013]
An exhaust control valve device according to a third aspect of the present invention is the exhaust control valve device according to the second aspect of the present invention, wherein the valve housing includes a housing body in which an exhaust passage is formed, and an exhaust control valve for the housing body. And a cover that closes the attachment / detachment port, and a shaft hole that supports one end of the exhaust control valve is formed in the cover, and an annular wall is provided in the shaft hole. The cover side pressure receiving plate of the exhaust control valve is opposed.
[0014]
According to the present invention, the exhaust control valve can be positioned with respect to the cover by the pressure receiving plate on the cover side of the exhaust control valve and the annular wall of the cover. Therefore, an assembly in which the exhaust control valve is assembled to the cover. Can be easily formed.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of an exhaust control valve device according to the present invention will be described in detail with reference to FIGS.
1 is a side view of a motorcycle using an exhaust control valve device according to the present invention, FIG. 2 is a view showing the exhaust device, FIG. 1 (a) is a side view, and FIG. 1 (b) is a plan view. 3 is a side view showing the state of the exhaust control valve device as viewed from the right side of the vehicle body. FIG. 4 is a longitudinal sectional view of the exhaust control valve device, and the broken position in FIG. 3 is indicated by line IV-IV in FIG.
5 is a side view of the valve housing, FIG. 6 is also a front view, FIG. 7 is a sectional view taken along line VII-VII in FIG. 5, FIG. 8 is a sectional view taken along line VIII-VIII in FIG. It is IX sectional view. FIG. 10 is a side view for explaining the operation of the exhaust control valve. FIG. 10 is drawn with the exhaust control valve broken. FIG. 11 is a view showing an exhaust control valve. FIG. 11A is a plan view, FIG. 11B is a side view, and in FIG.
[0016]
In these drawings, what is indicated by reference numeral 1 is a motorcycle according to this embodiment. The motorcycle 1 is of a so-called on-road type that runs using a four-cycle engine 2 as a power source, and includes a cowling 3 that covers a front portion of a vehicle body. Reference numeral 4 denotes a body frame of the motorcycle 1, 5 is a front wheel, 6 is a front fork, 7 is a steering handle, 8 is a fuel tank, 9 is a seat, 10 is a rear wheel, and 11 is a rear arm.
[0017]
The engine 2 is of the DOHC 4-cylinder type, and the cylinder 12 is attached to the crankcase 13 with the axial direction inclined forward and is supported by the tank rail 4a and the rear arm bracket 4b of the vehicle body frame 4. . The engine 2 has an intake device (not shown) attached to the rear surface of the cylinder 12 and an exhaust device 21 to be described later attached to the front surface.
[0018]
As shown in FIG. 2, the exhaust device 21 includes exhaust pipes 22 to 25 for each cylinder, an exhaust control valve device 27 interposed between the exhaust pipes 22 to 25 and the muffler 26 on the downstream side. is doing. The exhaust pipes 22 to 25 extend downward in front of the cylinder 12 of the engine 2, and are bent so that the downstream side faces the rear in the front lower direction of the crankcase 13.
[0019]
The downstream end portions of these exhaust pipes 22 to 25 have two exhaust pipes 22 and 25 (exhaust pipes connected to the # 1 cylinder and the # 4 cylinder) at both ends of the four exhaust pipes. The remaining two exhaust pipes 23 and 24 (exhaust pipes connected to the # 2 cylinder and the # 3 cylinder) which are adjacent to each other in the direction below the exhaust pipes 22 and 25 are arranged along the vehicle width direction. It forms so that it may mutually adjoin.
The muffler 26 includes a communication pipe 28 extending rearward from the exhaust control valve device 27 and a silencer 29 connected to the rear end portion of the communication pipe 28. The communication pipe 28 is formed by a plurality of pipes, and the silencer 29 is provided with a catalytic converter 30 therein.
[0020]
As shown in FIGS. 3 to 11, the exhaust control valve device 27 includes a valve housing 31 that connects the four exhaust pipes 22 to 25, and two butterflies that are rotatably supported by the valve housing 31. The exhaust control valve 32 of a type | mold, the drive device 33 which drives these exhaust control valves 32, etc. are provided.
As shown in FIGS. 3 and 4, the valve housing 31 includes a housing main body 34 having an exhaust passage S formed therein, and a cover 36 attached to the right end of the housing main body 34 by a fixing bolt 35. It is composed by.
[0021]
The housing body 34 is integrally formed with a first partition plate 37 that partitions the interior of the housing into two chambers arranged in the vertical direction and a second partition plate 38 that partitions the interior of the housing into two chambers aligned in the vehicle width direction. The exhaust pipe connecting flange 39 (see FIG. 6) is formed at the front end portion, and the tapered portion 40 is formed at the rear end portion. As shown in FIGS. 7 and 8, the taper portion 40 is formed so that the inner diameter of the housing body 34 gradually decreases toward the downstream side, and a cylinder 41 for connecting the communication pipe 28 to the rear end. Is provided.
[0022]
As shown in FIG. 7, the first partition plate 37 extends in the front-rear direction from the front end of the housing main body 34 to the communication pipe connecting cylinder 41, and the second partition plate 38 is connected to the housing main body 34. It extends from the front end to the center in the front-rear direction. That is, the exhaust passage S in the housing body 34 is first to second in the range where the second partition plate 38 is formed by the first and second partition plates 37 and 38 as shown in FIG. As shown in FIG. 8, the upper exhaust passage S5 and the lower exhaust are defined only by the first partition plate 37 in the range behind the second partition plate 38, which is defined by the fourth cylinder-specific exhaust passages S1 to S4. A passage S6 is defined. The 2nd partition plate 38 comprises the partition which defines the exhaust passage which concerns on this invention.
[0023]
As shown in FIGS. 5 and 8, the second partition plate 38 is formed with two notches 42 for inserting an exhaust control valve 32 described later. These notches 42 are formed in a shape in which two portions of the opening edge of the circular hole 42a partially extend outward in the radial direction. An extending portion extending outward in the radial direction is indicated by reference numeral 42b in FIGS.
[0024]
Further, as shown in FIG. 4, the housing body 34 is provided with an attachment / detachment port 43 through which the exhaust control valve 32 is attached and detached at the front part on the right side of the vehicle body. Bosses 44 and 45 that support the end portions are integrally formed. These bosses 44 and 45 project to the left side of the vehicle body in two vertical directions corresponding to the first cylinder-specific exhaust passage S1 and the second cylinder-specific exhaust passage S2 with the axis line directed in the vehicle width direction. It is formed as follows.
[0025]
As shown in FIG. 4, the cover 36 is formed so as to define a third cylinder specific exhaust passage S <b> 3 and a fourth cylinder specific exhaust passage S <b> 4 in cooperation with the housing main body 34. The bosses 46 and 47 that support the right end of the exhaust control valve 32 on the vehicle body are formed integrally with the bosses 44 and 45. These bosses 46 and 47 are also formed so that the axial direction is parallel to the vehicle width direction. In addition, inside the shaft holes 46a and 47a of the bosses 46 and 47, there are provided annular walls 46b and 47b that restrict the position of a bearing 55 described later and face the pressure receiving plate 54 on the right side of the vehicle body of the exhaust control valve 32. ing.
[0026]
As shown in FIGS. 4 and 11, the exhaust control valve 32 includes valve shafts 32a and 32b at both ends and two plate-like valve bodies 51, 51 and 3 between the valve shafts 32a and 32b. The pressure receiving plates 52 to 54 are integrally formed. Of the two valve shafts 32 a and 32 b, the valve shaft 32 a located at the left end in FIGS. 4 and 11 is formed in a cylindrical shape, and rotates around the bosses 44 and 45 of the housing body 34 via a bearing 55. It is supported freely.
[0027]
At the bottom of the bosses 44 and 45, as shown in FIG. 7, a screw hole 56 is provided through which a push rod (not shown) is inserted to facilitate pressing and removing the exhaust control valve 32 during maintenance. The screw holes 56 are provided at two locations facing the boundary portion between the valve shaft 32 a and the bearing 55. By providing the screw hole 56 in this manner, both the valve shaft 32 a and the bearing 55 can be pressed by the push rod inserted into the screw hole 56. As shown in FIG. 4, the screw hole 56 is usually screwed with a bolt 57 in order to prevent foreign matter from entering. The screw hole 56 may be provided in a portion facing the axial center portion of the valve shaft 32a.
[0028]
The valve shaft 32b at the other end of the exhaust control valve 32 is formed in a columnar shape, and a connecting rod 58 for connecting a driving device 33 (to be described later) is integrally formed at the shaft end. The bosses 46 and 47 of the cover 36 are rotatably supported. In this supported state, the pressure receiving plate 54 on the right side of the exhaust control valve 32 faces the annular walls 46b, 47b of the bosses 46, 47 from the exhaust passage side.
As shown in FIG. 11, the connecting rod 58 is formed such that a front end side fitting surface 58a and an inner fitting surface 58b, which are flat surfaces, are connected to each other with a step, and as shown in FIG. In the figure, connecting members denoted by reference numerals 59 and 60 are fitted and fixed by fixing bolts 61 and 62.
[0029]
These connecting members 59 and 60 constitute a part of a link mechanism 63 (see FIG. 3) that connects the two exhaust control valves 32 so as to be linked to each other. The connecting rods 58 are fitted to each other and are connected to each other via a single link 64. The connecting members 59, 60 are fixed to the connecting rod 58 by connecting the end face 58c (see FIG. 11) formed between the distal end side fitting surface 58a and the inner fitting surface 58b of the connecting rod 58 to the inside of the connecting member. The fixing bolts 61 and 62 are fastened with the end faces (not shown) in contact with each other.
[0030]
In this embodiment, as shown in FIG. 4, a gap is formed between the connecting members 59, 60 and the outer end surfaces of the bosses 46, 47 in the fastening state, and a washer 65 is provided in this gap. The disc spring 66 is elastically mounted. The disc spring 66 urges the entire exhaust control valve 32 together with the connecting members 59 and 60 to the right side of the vehicle body. In this way, the exhaust control valve 32 is biased in one axial direction by the elastic force of the disc spring 66, thereby preventing the exhaust control valve 32 from vibrating in the axial direction during operation and generating a hitting sound. Can do.
[0031]
The connecting member 59 attached to the upper exhaust control valve 32 (hereinafter simply referred to as the drive-side exhaust control valve 32) rotates one end of the link 64 at the lowermost position by the pivot 67 in the state shown in FIG. Install freely. The fixing bolt 61 for fixing the connecting member 59 to the connecting rod 58 is fastened to the connecting member 59 by a pulley 68 fitted in the fitting hole 59a of the connecting member 59 so that it cannot be relatively rotated from the outside. ing.
[0032]
In the state shown in FIG. 3, the connecting member 60 attached to the lower exhaust control valve 32 (hereinafter referred to simply as the driven exhaust control valve 32) pivots the other end of the link 64 to the left end. 69 is rotatably attached.
As described above, the driving side exhaust control valve 32 and the driven side exhaust control valve 32 are connected by the link 64, so that the driving force is linked when the driving side exhaust control valve 32 is rotated by the driving device 33 described later. The driven exhaust control valve 32 is rotated in a direction opposite to that of the drive exhaust control valve 32.
[0033]
Here, the rotation direction (opening / closing direction) of both the exhaust control valves 32 will be described. The two exhaust control valves 32 are fully opened in the state shown in FIG. 3, and are fully closed by rotating 90 ° from this state. As shown in FIG. 10, the fully open state is a state in which the plate-like valve body 51 of the drive side exhaust control valve 32 and the main surfaces 51a of the plate-like valve body 51 of the driven side exhaust control valve 32 are parallel to each other. That means. When shifting from the fully open state to the fully closed state, the drive side exhaust control valve 32 rotates counterclockwise in FIGS. 3 and 10, and the driven side exhaust control valve 32 rotates clockwise. In other words, both exhaust control valves 32 have the main surfaces 51a of the plate-like valve bodies 51 parallel to each other in the fully opened state, and the downstream edges 51b (FIG. 10) of the main surfaces 51a of the plate-like valve bodies 51 in the fully closed state. Rotate so that they are close to each other. The position of both exhaust control valves 32 when between the fully open position and the fully closed position is indicated by a two-dot chain line in FIG. When the exhaust control valve 32 is in the fully closed state, the exhaust gas flows through a gap formed between the plate-like valve body 51 and the valve housing 31.
[0034]
The rotational angle of both exhaust control valves 32 is controlled by a drive device 33 described later, but the fully closed position is mechanically determined by the connecting member 59 of the drive side exhaust control valve 32. That is, as shown in FIG. 3, the connecting member 59 of the drive side exhaust control valve 32 is provided with a protrusion 71 protruding upward in FIG. 3, and the protrusion is in a state where the drive side exhaust control valve 32 is rotated to the fully closed position. A closed stopper 72 with which 71 abuts is provided integrally with the cover 36, and both exhaust control valves 32 rotate in the closing direction until the projection 71 abuts against the closed stopper 72. In this embodiment, in order to restrict the drive-side exhaust control valve 32 from opening further in the opening direction than the fully open position, an open-side stopper with which the protrusion 71 abuts when the drive-side exhaust control valve 32 is excessively opened. 73 is provided integrally with the cover 36.
[0035]
In FIG. 3, a tension coil spring denoted by reference numeral 74 provided at the axial center of the driven exhaust control valve 32 is for preventing the driven exhaust control valve 32 from vibrating in a direction perpendicular to the axial direction. It is elastically mounted between a fixing bolt 62 for fixing the connecting member 60 and a pin 75 erected on the cover 36.
[0036]
As shown in FIG. 11A, the plate-like valve body 51 is formed in a shape substantially equal to the passage cross-sectional shape (see FIG. 9) of the first to fourth cylinder-specific exhaust passages S1 to S4 of the housing body 34. The cylinder-specific exhaust passages are provided for each cylinder so that the cylinder-by-cylinder exhaust passages can be opened and closed simultaneously. A recess 76 facing the second partition plate 38 of the housing main body 34 is formed between the plate-like valve bodies 51, and a pressure receiving plate 53 described later is integrally provided. The plate-like valve body 51 can be formed rounded as shown by a two-dot chain line in FIG. 11A, but as shown in this embodiment, the recess 76 is formed. By providing the corners, the housing main body 34 can be reduced in weight, and the exhaust gas passage can have a larger cross-sectional area and exhaust resistance can be reduced.
[0037]
As shown in FIGS. 10 and 11, the pressure receiving plates 52 to 54 are circular plates along a plane orthogonal to the axial direction of the exhaust control valve 32, and a portion where the plate-like valve body 51 in the exhaust control valve 32 is provided. The outer diameter is larger than the shaft diameter of the exhaust valve and the outer diameter is smaller than the maximum outer diameter of the plate-like valve body 51 viewed from the axial direction of the exhaust control valve 32. The maximum outer diameter is the maximum dimension in the direction perpendicular to the thickness direction of the plate-like valve body 51, and in FIG. 11 (a) is the maximum dimension in the vertical direction of the plate-like valve body 51. . Further, the outer diameters of these pressure receiving plates 52 to 54 are formed to coincide with each other. Further, as described above, the pressure receiving plates 52 to 54 have the first to fourth cylinders at a total of three locations between the plate valve bodies 51 and between the plate valve body 51 and the valve shafts 32a and 32b. It arrange | positions so that a part of inner wall of another exhaust passage S1-S4 may be comprised.
[0038]
That is, by incorporating the exhaust control valve 32 into the valve housing 31, as shown in FIG. 4, the pressure receiving plates 52 and 54 on both ends of the three pressure receiving plates 52 to 54 are connected to the bosses 44 to 47, respectively. While being inserted so as to close the shaft holes 44 a to 47 a, the pressure receiving plate 53 at the center is inserted into the notch 42 of the second partition plate 38 so as to close the circular hole 42 a. In this assembled state, the extended portion 42b of the notch 42 is kept open. The circular hole 42a has a hole diameter that allows the bearing 55 interposed between the shaft portion 32a of the exhaust control valve 32 and the bosses 44 and 45 to be inserted therethrough.
[0039]
Since the outer diameter of the bearing 55 coincides with the shaft holes 44a and 45a, the outer diameter of the left pressure receiving plate 52 whose diameter is smaller than that of the shaft holes 44a and 45a is smaller than that of the circular hole 42a. Since the outer diameters of the three pressure receiving plates 52 to 54 are all the same, a gap is formed between the hole wall surface and the pressure receiving plate 53 when the central pressure receiving plate 53 is inserted into the circular hole 42a. The If this gap is made smaller, the pressure receiving plate 53 becomes larger in diameter than the pressure receiving plates 52 and 54 on both sides and the pressure balance is lost. Therefore, in this embodiment, a configuration is formed in which a gap is intentionally formed. The second partition plate 38 is formed with the extending portion 42b of the notch 42 so that the exhaust gas can be circulated in a slight amount, so that the influence exerted by the size of the gap is small.
[0040]
As shown in FIG. 2, the drive device 33 that drives both the exhaust control valves 32 includes a motor unit 81 and two motor units 81 that transmit driving force from the motor unit 81 to the pulley 68 of the drive side exhaust control valve 32. The wire 82 is constituted by the link mechanism 63 that connects the exhaust control valves 32 to each other. The motor unit 81 fully closes both exhaust control valves 32 when the rotational speed of the engine 2 is lower than the idling rotational speed, and the engine rotational speed when the engine rotational speed is in a low rotational speed range including the idling rotational speed. The exhaust opening is increased so that the exhaust control valve 32 is fully opened when the rotation speed exceeds a predetermined high rotation speed, and is supported by the rear arm bracket 4b of the vehicle body frame 4. Yes.
[0041]
In FIG. 2B, what is indicated by reference numeral 83 located on the side of the exhaust control valve device 27 is an exterior cover that covers the link mechanism 63 from the right side of the vehicle body. The exterior cover 83 is fixed to the cover 36 of the exhaust control valve device 27 with fixing bolts (not shown). A screw hole into which the fixing bolt is screwed is indicated by reference numeral 84 in FIG.
[0042]
The exhaust control valve device 27 configured as described above is assembled by incorporating the exhaust control valve 32 into the housing body 34, attaching the cover 36 to the housing body 34, and connecting the link mechanism 63 and the drive device 33. The operation of incorporating the exhaust control valve 32 into the housing main body 34 is performed by inserting the exhaust control valve 32 into the housing from the attachment / detachment port 43 of the housing main body 34 with the bearing 55 attached to the shaft portion 32a on the left side of the vehicle body of the exhaust control valve 32. At the same time, it is inserted into the notch 42 of the second partition plate 38 and the bearing 55 is fitted into the shaft holes 44a and 45b of the bosses 44 and 45. The operation of inserting the exhaust control valve 32 into the notch 42 is performed by aligning the position of the plate-like valve body 51 with the extending portion 42 b of the notch 42. This assembling operation can also be performed by holding the exhaust control valve 32 on the cover 36 to form an assembly and assembling the assembly with the housing body 34. When assembled in this way, the exhaust control valve 32 can be positioned on the cover 36 by the pressure receiving plate 54 on the right side of the exhaust control valve 32 and the annular walls 46b and 47b on the cover 36 side.
[0043]
The exhaust control valve device 27 is configured such that when the engine is stopped, both exhaust control valves 32 are fully closed, and when the engine 2 is operated at, for example, idling speed, both the two-dot chain lines in FIG. The exhaust control valve 32 opens at a low opening. At this time, the pressure wave propagating through the exhaust passage S is reflected by the exhaust control valve 32, propagates through a relatively short propagation path, and returns to the engine 2. On the other hand, in a high-speed operation state in which the engine speed exceeds the predetermined high-speed rotation speed, the exhaust control valve 32 is fully opened, and the pressure wave propagating through the exhaust passage S is caused by the taper of the valve housing 31. Reflected by the part 40, propagates along a relatively long propagation path and returns to the engine 2.
[0044]
In the exhaust pipes 22 to 25 according to this embodiment, when the exhaust port of the engine 2 is opened while the exhaust control valve 32 is closed at a low speed, a negative reflected wave reaches the exhaust port, and the exhaust pipe is exhausted at a high speed. The exhaust pipe length is set so that a negative reflected wave reaches the exhaust port when the exhaust port of the engine 2 is opened while the control valve 32 is open. It has a structure that can improve output during both high-speed operation.
[0045]
Further, when the engine speed is relatively low, the exhaust control valve 32 functions as a guide that substantially changes the flow direction of the exhaust gas, and the exhaust gas is indicated by an arrow drawn by a two-dot chain line in FIG. It flows toward the first partition plate 37 side. In this way, a large amount of the exhaust gas brought to the first partition plate 37 side flows from the exhaust control valve device 27 to the central portion in the radial direction of the communication pipe 28, and flows into the silencer 29 from the communication pipe 28. Since a large amount of exhaust gas flows through the central portion of the communication pipe 28, the amount of exhaust gas that comes into contact with the communication pipe 28 that is exposed to the outside air and becomes relatively low in temperature is reduced. The temperature can be kept relatively high. As a result, the catalytic converter 30 quickly reaches the activation temperature after the engine is started, and the exhaust gas can be purified from an early stage.
[0046]
When exhaust gas flows through the exhaust control valve device 27, the pressure of the exhaust gas also acts on the exhaust control valve 32. The exhaust control valve 32 is provided with a pressure receiving plate 54 so as to be paired with one side and the other side of each of the first to fourth cylinder specific exhaust passages S1 to S4. The pressure in the exhaust passage for each cylinder applied to the cylinder 32 is canceled by the pressure receiving plates 52 to 54. In the pressure receiving plates 52 to 54, the plate-like valve body 51 is formed for each cylinder exhaust passage, and it is not necessary to form a large hole in the second partition plate 38 so that the plate-like valve body 51 can rotate. Therefore, it can be formed in the minimum necessary size. For this reason, even with the structure in which the pressure receiving plates 52 to 54 are provided at three locations, the assembling work of the exhaust control valve 32 is simple.
[0047]
Further, the notch 42 formed in the second partition plate 38 can be formed in substantially the same shape as the plate valve body 51 and the pressure receiving plates 52 to 54 viewed from the axial direction. The circular hole 42 a through which the pressure receiving plate 52 passes in the notch 42 is substantially closed by the pressure receiving plate 53 during operation, so that it is difficult for pressure waves to leak from the opening formed in the second partition plate 38. For this reason, the engine output can be improved by efficiently using the exhaust pulsation.
Furthermore, the exhaust control valve device 27 according to this embodiment employs a link mechanism 63 for connecting the drive side exhaust control valve 32 and the driven side exhaust control valve 32 so as to rotate in opposite directions. Compared with the case where the same function is realized by gears, the structure is simple and the number of parts is small.
[0048]
In the above-described embodiment, a structure in which two cylinder-specific exhaust passages are opened and closed by one exhaust control valve 32 is employed. However, the number of exhaust passages opened and closed by the exhaust control valve 32 can be changed as appropriate. For example, a structure in which the first to fourth cylinder-specific exhaust passages S1 to S4 are arranged in a line and these exhaust passages are opened and closed by a single exhaust control valve 32 may be employed.
[0049]
【The invention's effect】
As described above, according to the present invention, since the pressure of each exhaust passage applied to the exhaust control valve is canceled by the pressure receiving plate, the sound of the exhaust control valve being pressed against the valve housing by the pressure of the exhaust passage. Will not occur. In the pressure receiving plate, a plate-like valve body is formed for each exhaust passage, and it is not necessary to form a large hole in the partition wall so that the plate-like valve body can rotate. It can be made small so that it can be attached. The notch formed in the partition can be formed in the same shape as the plate valve body and the pressure receiving plate when viewed from the axial direction, and the part of the notch through which the pressure receiving plate passes is pressure-receiving during operation. Closed with a plate. For this reason, since the hole formed in a partition can be formed in the elongate shape which can let a plate-shaped valve body pass, the leakage of a pressure wave decreases compared with the case where a large circular hole is formed.
Therefore, it is possible to provide an exhaust control valve device that uses a butterfly-type exhaust control valve, does not leak pressure waves and does not generate sound, and is easy to assemble.
[0050]
According to the second aspect of the present invention, since the pressure of the exhaust passage similarly acts on the two pressure receiving plates for each exhaust passage, the exhaust control valve is moved in the axial direction even if the pressure of the two exhaust passages changes alternately. There is no energizing force. For this reason, it is possible to reliably prevent the hitting sound from being generated when the exhaust control valve is pressed against the valve housing by the pressure of the exhaust passage.
[0051]
According to the third aspect of the present invention, the exhaust control valve can be positioned with respect to the cover by the pressure receiving plate on the cover side of the exhaust control valve and the annular wall of the cover. Can be easily formed. For this reason, since the exhaust control valve device can be assembled by assembling the assembly into the housing body, an exhaust control valve device that can be easily assembled can be provided.
[Brief description of the drawings]
FIG. 1 is a side view of a motorcycle using an exhaust control valve device according to the present invention.
FIG. 2 is a view showing an exhaust device.
FIG. 3 is a side view of the exhaust control valve device as viewed from the right side of the vehicle body.
FIG. 4 is a longitudinal sectional view of an exhaust control valve device.
FIG. 5 is a side view of the valve housing.
FIG. 6 is a front view of the valve housing.
7 is a cross-sectional view taken along the line VII-VII in FIG.
8 is a cross-sectional view taken along line VIII-VIII in FIG.
9 is a cross-sectional view taken along line IX-IX in FIG.
FIG. 10 is a side view for explaining the operation of the exhaust control valve.
FIG. 11 is a view showing an exhaust control valve.
[Explanation of symbols]
27 ... Exhaust control valve device, 31 ... Valve housing, 32 ... Exhaust control valve, 33 ... Drive device, 34 ... Housing body, 36 ... Cover, 37 ... First partition plate, 38 ... Second partition plate, 42 ... Notch, 46b, 47b ... annular wall, 32a, 32b ... valve shaft, 51 ... plate-shaped valve body, 52-54 ... pressure receiving plate, 63 ... link mechanism, S ... exhaust passage.

Claims (3)

An exhaust control valve device in which at least two exhaust passages are provided side by side in a valve housing, and a butterfly type exhaust control valve having an axial direction as the direction in which the exhaust passages are provided is rotatably provided. The housing has a structure in which an exhaust control valve is incorporated in the axial direction, and the exhaust control valve includes a valve shaft, a plate-shaped valve body for each exhaust passage provided in the valve shaft, and between these plate-shaped valve bodies. A plurality of pressure receiving plates provided at both ends of the exhaust control valve so as to constitute a part of the inner wall of each exhaust passage, and the pressure receiving plate is a disc along a plane perpendicular to the axis of the valve shaft The outer diameter of the portion where the plate-shaped valve body is provided is larger than the shaft diameter and smaller than the maximum outer diameter of the plate-shaped valve body, and the exhaust passages in the valve housing are connected to each other. The pressure plate on the partition wall And plate-like valve body is made by forming a notch capable of inserting an exhaust control valve device. The exhaust control valve device according to claim 1, wherein the outer diameters of the three pressure receiving plates of the exhaust control valve are made to coincide with each other. 3. The exhaust control valve device according to claim 2, wherein the valve housing is constituted by a housing main body in which an exhaust passage is formed and a cover for closing the exhaust control valve attaching / detaching port of the housing main body, and the exhaust control valve is provided in the cover. An exhaust control valve in which a shaft hole for supporting one end portion is formed, an annular wall is provided in the shaft hole, and a pressure receiving plate on the cover side of the exhaust control valve is opposed to the exhaust passage side from the annular wall.

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