JP6730413B2 - Motorcycle - Google Patents

Description

The present invention relates to an improvement of a motorcycle equipped with an exhaust gas sensor.

BACKGROUND ART An engine exhaust system including an exhaust gas sensor capable of detecting an exhaust gas component in exhaust gas is known (see, for example, Patent Document 1 (FIG. 3)).

As shown in FIG. 3 of Patent Document 1, an exhaust device (6) for an engine (numerals in parentheses indicate reference numerals described in Patent Document 1. The same applies hereinafter) is an exhaust pipe (7) extending from an exhaust port of the engine. And a silencer (8) connected to the downstream end (7a) of the exhaust pipe (7), and the downstream end (7a) is housed in the silencer (8). A three-way catalyst (10) (hereinafter referred to as "catalyst") is arranged in the exhaust pipe (7), and an O2 sensor (14) (hereinafter referred to as "exhaust gas sensor ( 14)”) is arranged.

By the way, the muffler (8) has an expansion chamber having a predetermined capacity. If the exhaust gas sensor (14) is provided in such a silencer (8), the exhaust gas sensor (14) is provided so as to project to the outside of the silencer (8), which tends to increase the size of the vehicle. is there.
In a motorcycle equipped with an exhaust gas sensor in the vicinity of a silencer, a technique capable of suppressing the size increase of the vehicle is desired.

International Publication No. WO2005/075805

It is an object of the present invention to provide a technique for a motorcycle equipped with an exhaust gas sensor in the vicinity of a silencer, which is capable of suppressing an increase in the size of the vehicle.

According to a first aspect of the present invention, a swing arm that rotatably supports rear wheels, an engine, an exhaust pipe connected to an exhaust port of the engine, an exhaust pipe that is disposed outside the swing arm, and a rear exhaust pipe is provided. A silencer connected to the end, a catalyst provided in the exhaust pipe, an exhaust gas sensor capable of detecting the exhaust gas component in the exhaust pipe, the catalyst, the catalyst is provided upstream of the exhaust gas sensor, muffler includes a muffler and the enlarged diameter portion gradually being enlarged from the junction of the exhaust pipe extending from the enlarged diameter portion to the rear, and a cylindrical portion of larger cross-section than the enlarged diameter portion, the enlarged diameter A recessed portion that is recessed toward the exhaust pipe, the exhaust gas sensor is attached to this recessed portion, and the center of the exhaust pipe is provided at a position that corresponds to the recessed portion and is closer to the recessed portion than the center of the expanded diameter portion. and characterized in that it is.
The invention according to claim 2 is characterized in that the silencer includes a wall portion that overlaps with at least one of the front, left, and right of the exhaust gas sensor.
The invention according to claim 3 is characterized in that the exhaust gas sensor is arranged above the center of the exhaust pipe.
The invention according to claim 4 is characterized in that the exhaust gas sensor is arranged inside in the vehicle width direction with respect to the center of the exhaust pipe.

The invention according to claim 5 is characterized in that, in a front view of the vehicle, the exhaust gas sensor is arranged at a position overlapping the crankcase of the engine.

The invention according to claim 6 is characterized in that the motorcycle further includes a pillion step on which a passenger places his/her foot, and an exhaust gas sensor is arranged inside the pillion step.

In the invention according to claim 7 , the silencer is supported by the passenger step, and wiring extends from the exhaust gas sensor, and the wiring is routed inside the vehicle body cover along the inside of the pillion step. It is characterized by being

In the invention according to claim 1, the exhaust gas sensor is attached to the expanded diameter portion provided in the silencer. If the exhaust gas sensor can be mounted using the space of the expanded diameter portion, the exhaust gas sensor can be arranged so that it does not overhang radially outward as compared with the case where the exhaust gas sensor is mounted in the tubular portion. Therefore, in a motorcycle having an exhaust gas sensor behind the catalyst, it is possible to prevent the vehicle from increasing in size. Further, a recess is provided in the expanded diameter portion, and the exhaust gas sensor is attached to this recess. Since the exhaust gas sensor is housed in the recess, the amount of protrusion of the exhaust gas sensor can be suppressed as compared with the case where the recess is not formed. In addition, since the amount of protrusion of the exhaust gas sensor is reduced, the exhaust gas sensor is less susceptible to external influences and can be protected from flying stones and the like. Further, the center of the exhaust pipe is provided at a position closer to the recess from the center of the expanded diameter portion. Since the exhaust pipe is arranged close to the concave portion, the amount of depression of the concave portion can be reduced. If the recess has a small amount of depression, the processing cost can be suppressed.

In the invention according to claim 5 , the exhaust gas sensor is arranged at a position overlapping the crankcase of the engine when the vehicle is viewed from the front. During traveling, flying stones scattered from the front hit the crankcase, and it is difficult for the exhaust gas sensor arranged behind the crankcase to hit. As a result, the exhaust gas sensor can be protected from flying stones and the like from the front.

In the invention according to claim 6 , the exhaust gas sensor is arranged inside the passenger step. Since the exhaust gas sensor is arranged inside the passenger step, the exhaust gas sensor is unlikely to get in the way when placing a foot on the passenger step.

In the invention according to claim 7 , the silencer is supported by the passenger step, the wiring extends from the exhaust gas sensor, and the wiring is routed inside the vehicle body cover along the inside of the passenger step. Therefore, it is possible to carry out the planning without considering the influence of swinging of the swing arm. That is, once the wiring is to be routed along the swing arm, it is necessary to provide a measure to bend the wiring between the silencer and the swing arm.
However, in the present invention, the wiring is routed along the inside of the passenger step in the vehicle body cover by arranging the wiring along the step of supporting the silencer. There is no need to take any measures to flex the arrangement.

FIG. 1 is a right side view of a motorcycle according to the present invention. 1 is a front view of a motorcycle according to the present invention. It is a top view of a silencer provided with an exhaust gas sensor and its surroundings. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 1, illustrating the arrangement structure of the exhaust gas sensor and the like. It is a right view of a silencer with a part broken. It is a top view of a silencer. FIG. 7 is a cross-sectional view taken along line 7-7 of FIG. 1, illustrating the layout between the exhaust gas sensor and the swing arm. FIG. 8 is a sectional view taken along line 8-8 of FIG. 1.

Hereinafter, embodiments of the present invention will be described in detail. In the drawings and the examples, “upper”, “lower”, “front”, “rear”, “left”, and “right” respectively indicate directions as seen from the driver who rides on the motorcycle.

An embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, a motorcycle 10 includes a vehicle body frame 11, an engine 12 suspended on the vehicle body frame 11, a front wheel 13 rotatably provided on the vehicle body frame 11, and a pivot portion 15 of the vehicle body frame 11. A swing arm 16 swingably supported on the vehicle body frame 11, a rear wheel 14 provided on the rear end of the swing arm 16 and rotatably supported, and a vehicle body frame 11 provided between the front wheel 13 and the rear wheel 14. It is a saddle-ride type vehicle that has a seat 17 on which an occupant sits and on which the occupant rides.

The vehicle body frame 11 includes a head pipe 21 that rotatably supports the front wheels 13, a main frame 22 that extends from the head pipe 21 obliquely rearward and downward in a substantially arcuate shape, and below the main frame 22. A down frame 23 extending obliquely downward and rearward of the vehicle from the head pipe 21, a pivot portion 15 provided at a lower end of the main frame 22, and seat rails 24L and 24R extending rearward from an intermediate portion of the main frame 22 (front side in the drawing). 24R) and the support frames 25L, 25R (only the reference numeral 25R on the front side of the drawing is shown) passed between the seat rails 24L, 24R and the pivot portion 15 are main elements.

A steering shaft 31 is rotatably provided on the head pipe 21, a steering handle 32 is attached to the upper end of the steering shaft 31, and a front fork 33 that supports the front wheel 13 extends from the lower end of the steering shaft 31. Cushion units 34L and 34R (only reference numeral 34R on the front side in the drawing is shown) are passed between the swing arm 16 and the seat rails 24L and 24R. A front fender 35 is attached to the front fork 33, and a rear fender 36 is attached to the seat rails 24L and 24R. A fuel tank 37 is arranged behind the steering handle 32, and a seat 17 is arranged continuously behind the fuel tank 37.

The fuel tank 37 is supported by the main frame 22, and the seat 17 is supported by the seat rails 24L, 24R. Further, a driver step 38 allowing the driver to place his/her feet from the engine 12 extends laterally in the vehicle width direction, and passengers steps 39L, 39R allowing the passenger to place his/her feet from the support frames 25L, 25R. (Only reference numeral 39R on the front side of the drawing is shown.) extends laterally in the vehicle width direction.

An exhaust device 40 extends from the engine 12, and the exhaust device 40 is connected to an exhaust pipe 41, a catalyst 42 interposed in the exhaust pipe 41, and a downstream end (rear end) of the exhaust pipe 41. The silencer 43 is the main element. The silencer 43 is connected to the rear end of the exhaust pipe 41 and arranged outside the swing arm 16.

The upstream end of the exhaust pipe 41 is connected to the exhaust port 66 of the engine 12, the rear portion of the exhaust pipe 41 is attached to the pivot portion 15 via the first stay 45, and the silencer 43 connects the second stay 46. It is attached to and supported by the passenger step 39 via.

The engine 12 is attached to the lower end of the down frame 23 via the front engine hanger 47, and is attached to the pivot portion 15 via the rear engine hanger 48. A brake pedal 49 is rotatably provided on the pivot portion 15.

The engine 12 includes a crankcase 51, a cylinder block 52 mounted and mounted on the upper surface of the crankcase 51, a cylinder head 53 mounted and mounted on the upper surface of the cylinder block 52, and an upper surface of the cylinder head 53. An oil pan 55 is mounted on the lower surface of the crankcase 51 from below to above. A clutch cover 56 is attached to the front right side surface of the crankcase 51 in the drawing.

The intake device 60 is connected to the rear surface 53b of the cylinder head 53. An exhaust port 66 is provided on the front surface 53a of the cylinder head 53, and the exhaust device 40 is connected to the exhaust port 66.

Next, the vehicle body covers will be described.
The vehicle body cover 70 includes a front cowl 71 that covers the front of the head pipe 21, tank tanks 72L and 72R that cover the front side of the fuel tank 37 behind the front cowl 71 (only the front side 72R in the drawing is shown). Behind the tank cowls 72L and 72R, midside covers 73L and 73R (only 73R on the front side of the drawing is shown) that covers the rear portion of the main frame 22 and the pivot portion 15 are provided so as to be continuous with the midside cover 73. The rear side covers 74L and 74R (only the front side 74R in the drawing is shown). A license stay 75 is provided below the front cowl 71 so as to project forward and to which a license plate is attached.

As shown in FIG. 2, the crankcase 51 of the engine 12 is provided so as to project to the left and right outside in the vehicle width direction when the vehicle is viewed from the front. An exhaust pipe 41 is provided in front of the crankcase 51. The exhaust pipe 41 extends below the crankcase 51. Returning to FIG. 1, the exhaust pipe 41 extending below the crankcase 51 extends toward the rear of the vehicle, and its downstream side is connected to the silencer 43.

Next, the structure and the like of the fellow passenger step (fellow passenger step) will be described.
As shown in FIG. 3, the left and right passenger steps 39L and 39R on which the passenger places his/her feet respectively extend outward from the support frames 25L and 25R (see FIG. 1) in the vehicle width direction, and then downward on the back side of the drawing. Pipe-shaped first arms 81L, 81R and second arms 82L, 82R that extend toward, and step-side stays 83L provided at the lower ends of these first arms 81L, 81R and second arms 82L, 82R, respectively. 83R, and foot rests 84L and 84R projecting outward from the step side stays 83L and 83R in the vehicle width direction.

A boss portion 85 is attached to the right step side stay 83R that is a component of the right passenger step 39R. The silencer-side second stay 46 is fastened to the boss portion 85 via a fastening member 86. That is, the muffler 43 is supported by the right passenger step 39R.

The arrangement of the exhaust device and the exhaust gas sensor will be described in detail below.
As shown in FIG. 4, a muffler 43 is arranged below the right passenger step 39R, and a muffler cover 77 is attached to the outer surface of the muffler 43. A second stay 46 is provided on the inner side surface of the silencer 43, an exhaust gas sensor 67 is arranged in front of the second stay 46 in the vehicle, and a wiring 68 extends from the exhaust gas sensor 67.

Referring to FIGS. 1 and 3 together, the exhaust gas sensor 67 is arranged inside the passenger step 39R. The wiring 68 extending from the exhaust gas sensor 67 is routed along the inside of the passenger step 39R and then routed along the passenger step 39R.

As shown in FIGS. 5 and 6, the muffler 43 includes a case portion 91, a separator portion 92 that partitions the inside of the case portion 91, and a rear end portion of the exhaust pipe 41 that is routed inside the case portion 91. And a pipe member 93 connected to the. The exhaust pipe 41 is connected to the upstream end of the pipe member 93.

The case portion 91 includes a joint portion 94 that is joined to the exhaust pipe 41, an enlarged diameter portion 95 that is enlarged in diameter so that the outer diameter gradually increases from the joint portion 94, and a rear end portion of the enlarged diameter portion 95. And a cap portion 97 that closes the downstream end of the cylindrical portion 96.

The separator portion 92 includes a first separator 101 and a second separator 102 provided behind the first separator 101 in the vehicle. The first separator 101 and the second separator 102 are arranged in a direction perpendicular to the longitudinal direction of the case portion 91. The first separator 101 is arranged near the boundary between the expanded diameter portion 95 and the cylindrical portion 96, and the second separator 102 is arranged at the rear portion of the cylindrical portion 96. By these first separator 101 and second separator 102, the case portion 91 is divided into a first chamber 104, a second chamber 105, and a third chamber 106 in this order from front to back.

The pipe member 93 of the muffler 43 is supported by the first separator 101 and the second separator 102 and extends to the third chamber 106. The first pipe member 107 is supported by the second separator 102 and the cap portion 97. It consists of two tube members 108. At the position facing the second chamber 105, the first pipe member 107 is provided with a first diffuser portion 114 having a large number of first holes 111 and flowing exhaust gas to the outside of the first pipe member 107. At the position facing the chamber 106, the rear end 107b of the first pipe member 107 is closed by the small cap 117, and at the position in front of the small cap 117 facing the third chamber 106, the third diffuser portion 116 is provided. Is provided. At a position facing the third chamber 106, the second pipe member 108 is provided with a second diffuser portion 115 having a large number of second holes 112 and flowing exhaust gas to the outside of the second pipe member 108.

The exhaust gas that has entered the first pipe member 107 flows from the first hole 111 to the second chamber 105, passes through the third hole 113 provided in the third diffuser portion 116, and flows to the third chamber 106 to generate the third gas. The exhaust gas that has flowed into the chamber 106 enters the second pipe member 108 through the second hole 112, and is discharged outside from the rear end of the second pipe member 108. The exhaust gas flowing into the second chamber 105 enters from the front end of the second pipe member 108 and is discharged to the outside from the rear end of the second pipe member 108.

The exhaust pipe 41 passes through the inside of the first chamber 104, passes through the first separator 101, and is connected to the upstream end of the pipe member 93 that constitutes the silencer 43. That is, the exhaust pipe 41 extends to the inside of the silencer 43. A catalyst 42 is provided in the exhaust pipe 41. The catalyst 42 is provided in the vicinity of the joint portion 94 between the silencer 43 and the exhaust pipe 41. An exhaust gas sensor 67 capable of detecting an exhaust gas component in the exhaust pipe is provided in the exhaust pipe 41 on the downstream side of the catalyst 42. The exhaust gas sensor 67 is attached to the expanded diameter portion 95 of the silencer 43.

As shown in FIG. 7, the enlarged diameter portion 95 is provided with a recess 121 that is recessed toward the exhaust pipe 41, and the exhaust gas sensor 67 is attached to the recess 121. The exhaust pipe 41 is provided at a position close to the recess 121 at a position corresponding to the recess 121.

The exhaust gas sensor 67 is attached to the expanded diameter portion 95 and is provided between the exhaust pipe 41 and the swing arm 16. The expanded diameter portion 95 is provided with a recess 121 that is recessed toward the exhaust pipe 41, and the exhaust gas sensor 67 is attached to the recess 121. As described above, the exhaust pipe 41 is provided at a position near the recess 121 at a position corresponding to the recess 121.

Returning to FIG. 2, the exhaust gas sensor 67 is arranged at a position overlapping the crankcase 51 of the engine 12 when the vehicle is viewed from the front. That is, the exhaust gas sensor 67 is arranged behind the crankcase 51 so as to overlap the crankcase 51.

Since the exhaust gas sensor 67 is arranged at a position overlapping the crankcase 51 of the engine 12, flying stones and the like scattered from the front hit the crankcase 51 during traveling, and the exhaust gas sensor 67 arranged behind the crankcase 51 does not. It's hard to hit. As a result, the exhaust gas sensor 67 can be protected from flying stones from the front.

As shown in FIG. 8, the first stay 45R of the pipe-shaped first stay 45R and the second stay 46R, which is a component of the right passenger step 39R, is recessed inward in the vehicle width direction. The part 122 is formed. The wiring 68 extending from the exhaust gas sensor 67 was provided along the recess 122. The recess 122 is covered with a cover member 78, which is a component of the vehicle body cover 70, from the inside in the vehicle width direction. That is, the wiring 68 is arranged inside the cover member 78, which is a component of the vehicle body cover 70, along the insides of the passenger steps 39L and 39R.

In the present embodiment, the wiring is covered with the cover member, but in addition to this, for example, the rear side cover and the rear fender may be extended to cover the passenger step from the inside.

The operation of the motorcycle equipped with the above-described exhaust gas sensor will be described below.
Returning to FIG. 7, the exhaust gas sensor 67 is attached to the expanded diameter portion 95 provided in the silencer 43. If the exhaust gas sensor 67 can be attached using the space of the expanded diameter portion 95, the exhaust gas sensor 67 can be arranged so as not to overhang to the outside of the silencer 43. Therefore, in the motorcycle 10 in which the silencer 43 is provided with the exhaust gas sensor 67, it is possible to prevent the vehicle from increasing in size. Further, since the exhaust gas sensor 67 is arranged so as to be sandwiched between the exhaust pipe 41 and the swing arm 16, there is no fear of impairing the external appearance of the vehicle.

Further, the enlarged diameter portion 95 is provided with a recess 121, and the exhaust gas sensor 67 is attached to the recess 121. Since the exhaust gas sensor 67 is housed in the recess 121, the amount of protrusion of the exhaust gas sensor 67 can be suppressed as compared with the case where the recess 121 is not formed. Moreover, since the amount of protrusion of the exhaust gas sensor 67 is reduced, it is possible to reduce the influence of the outside.

The exhaust pipe 41 is provided near the recess 121. Since the exhaust pipe 41 is arranged close to the recess 121, the amount of recess of the recess 121 can be reduced. If the recess 121 has a small amount of depression, the number of processing steps can be suppressed.

Returning to FIGS. 3 and 4, the exhaust gas sensor 67 is disposed inside the passenger steps 39L and 39R. Since the exhaust gas sensor 67 is arranged inside the passenger steps 39L and 39R, the exhaust gas sensor 67 is unlikely to get in the way when placing a foot on the passenger steps 39L and 39R.

With reference to FIGS. 1 and 8 together, the wiring 68 extending from the exhaust gas sensor 67 is routed inside the vehicle body cover 70 along the inside of the passenger step 39R on which the silencer 43 is supported. If the wiring extending from the exhaust gas sensor is to be routed along the muffler, the temperature of the muffler rises and the routing is difficult. It is necessary to take heat shield measures separately. In addition, once the wiring is arranged along the swing arm, it is necessary to provide a measure for bending the wiring between the silencer and the swing arm.

In this respect, according to the present invention, the wiring 68 is arranged inside the vehicle body cover 70 along the inside of the passenger step 39R, and therefore, there is no need to take a measure to arrange the wiring 68 by bending it. The passenger step 39R on which the passenger places his foot also has a function of supporting the silencer 43, and the wiring 68 of the exhaust gas sensor 67 extending from the silencer 43 is arranged inside the passenger step 39R. .. Since the passenger step 39R does not swing, the length of the wiring 68 can be shortened. Further, since the wiring 68 is arranged inside the passenger step 39R, the wiring 68 cannot be seen from the outside, and there is no fear of impairing the appearance of the vehicle.

The exhaust gas sensor of this embodiment uses an oxygen sensor (O2 sensor) that measures the oxygen concentration in the exhaust gas. The O2 sensor is preferable because it is inexpensive, but the O2 sensor is not limited to the O2 sensor, and any type of sensor may be used as long as it can detect a component in exhaust gas. For example, there are a CO sensor and a NOx sensor.

Although the present invention is applied to a motorcycle in the embodiment, it is also applicable to a three-wheeled vehicle and may be applied to a general vehicle.

The present invention is suitable for a motorcycle having an exhaust pipe equipped with an exhaust gas sensor.

10... Motorcycle, 12... Engine, 14... Rear wheel, 16... Swing arm, 39L, 39R... Passenger step (pillion step), 41... Exhaust pipe, 42... Catalyst, 43... Silencer, 51... Crankcase, 66... Exhaust port, 67... Exhaust gas sensor, 68... Wiring, 78... Cover member, 94... Joint part, 95... Expanded part, 121... Recessed part.

Claims (7)

A swing arm (16) for rotatably supporting the rear wheel (14),
Engine (12),
An exhaust pipe (41) connected to an exhaust port (66) of the engine (12),
A silencer (43) arranged outside the swing arm (16) and connected to a rear end of the exhaust pipe (41),
A catalyst (42) provided in the exhaust pipe (41),
A motorcycle comprising an exhaust gas sensor (67) capable of detecting an exhaust gas component in the exhaust pipe (41),
The catalyst (42) is provided upstream of the exhaust gas sensor (67),
The silencer (43) includes a diameter-expanded portion (95) having a diameter gradually increased from a joint (94) between the silencer (43) and the exhaust pipe (41), and a diameter-expansion portion (95). A tubular portion (96) extending rearward and having a cross section larger than the expanded diameter portion,
The expanded portion (95) is provided with a recess (121) recessed toward the exhaust pipe (41), and the exhaust gas sensor (67) is attached to the recess (121),
The center (C2) of the exhaust pipe (41) is provided at a position corresponding to the recess (121) and closer to the recess (121) from the center (C1) of the expanded diameter part (95). A motorcycle characterized by. The motorcycle according to claim 1, wherein the silencer (43) includes a wall portion (121) overlapping at least one of a front side, a left side, and a right side of the exhaust gas sensor (67). The motorcycle according to claim 1 or 2, wherein the exhaust gas sensor (67) is arranged above the center (C2) of the exhaust pipe (41). The said exhaust gas sensor (67) is arrange|positioned inside a vehicle width direction with respect to the center (C2) of the said exhaust pipe (41), The automatic of any one of Claims 1-3 characterized by the above-mentioned. Motorcycle. In the front view of the vehicle, said exhaust gas sensor (67) is a motorcycle of claim 1 any one of claims 4, characterized in that arranged in the crankcase (51) and overlapping position of said engine (12) .. The motorcycle is further provided with a passenger step (39) on which the passenger places his foot.
Inside the passenger step (39), said exhaust gas sensor (67) is any one motorcycle according to claim 1 to 5, characterized in that it is arranged. The silencer (43) is supported by the passenger step (39),
A wire (68) extends from the exhaust gas sensor (67),
Motorcycle according to claim 6 , characterized in that the wiring (68) is routed inside the body cover (78) along the inside of the passenger step (39).

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