JPS6350406Y2 - - Google Patents

Description

[Detailed explanation of the invention] In front and rear V-type engines installed in motorcycles, in order to simplify the intake system, the intake system is placed between the front and rear cylinders, resulting in an exhaust pipe connected to the rear cylinder. is located at the rear of the cylinder. For this reason, the exhaust pipe connected to the rear cylinder is not strongly affected by the wind while the vehicle is running, so it is difficult to cool down and the exhaust pipe tends to reach a high temperature.

In addition, in order to prevent electrical components such as batteries installed diagonally above the exhaust pipe connected to the rear cylinder from being affected by the heat dissipated from this exhaust pipe, It was considered to install a heat shield plate on the exhaust pipe, but since the two exhaust pipes were covered with a single thin and wide plate, the problem was that it would shake due to engine vibrations and cause noise.

The present invention relates to an improvement of the exhaust pipe heat shield plate of front and rear V-type engines for motorcycles that overcomes these difficulties.The purpose of this invention is to increase the rigidity so that resonance is less likely to occur and the heat dissipation and heat insulation properties are improved. The purpose of this invention is to provide an excellent exhaust pipe heat shield plate.

An embodiment of the present invention illustrated in the drawings will be described below.

Reference numeral 1 denotes a motorcycle, and the frame 2 of the motorcycle 1 includes a head pipe 3, a main pipe 4, a down tube 5, a backstay 6, and a seat rail 7, which are integrally connected to each other.

The head pipe 3 also includes a handle steering device 8.
A front fork 9 is attached to the front fork 9 so as to be swingable from side to side, and a front wheel 10 is pivotally attached to the lower end of the front fork 9.

Furthermore, the front end of a rear fork 13 is pivoted to the bottom plate 11 located at the connection between the main pipe 4 and the down tube 5 via a rear fork pivot 12 so as to be able to swing up and down. A wheel 14 is pivotally mounted, and the front end of the rear fork 13 and the seat rail 7 are connected via a rear suspension 15.

Further, a front and rear V-type engine 16 is mounted in a space surrounded by the main pipe 4 and the down tube 5, and the engine 16 has two cylinders 17 arranged in each front and rear cylinder row.

Therefore, an air cleaner 18 is disposed between the front and rear cylinders 17f and 17r, and the air cleaner 18
is connected to the front and rear cylinders 17 via the carburetor 19.
It is connected to intake ports (not shown) of engines f and 17r, and the intake system of the engine 16 is made compact.

Further, the front end of an exhaust pipe 20f is connected to an exhaust port (not shown) of the front cylinder 17f, and the exhaust pipe 20f is curved so as to bypass the lower part of the engine 16, and is connected to an exhaust collection chamber located at the rear of the lower part of the engine 16. The rear end of the exhaust pipe 20f is connected to the exhaust pipe 21.

Further, the front end of an exhaust pipe 20r is connected to an exhaust port (not shown) of the rear cylinder 17r, and the exhaust pipe 20r is bent downward and its rear end is connected to the exhaust collecting chamber 21.

Furthermore, the front end of a muffler 22 is connected to the exhaust collection chamber 21, and the muffler 22 is connected to the backstay 6 via a pillion step holder 23.

A side cover 24 is attached to the outer side of the connection between the exhaust gas collecting chamber 21 and the muffler 22, and the side cover 24 makes it appear as if the muffler 22 is directly connected to the front exhaust pipe 20f. It's starting to give you a feeling.

Further, female screws 25 are integrally fixed to two upper and lower parts of the side surface of the rear exhaust pipe 20r by welding or the like.

Furthermore, a heat shield plate 26 is placed across the two left and right rear exhaust pipes 20r, and both sides 27 of the heat shield plate 26 are curved so as to cover the outer surface of the left and right rear exhaust pipes 20r. Holes 28 and 29 are provided in the heat shield plate 26 at locations corresponding to the holes of the screws 25, and the lower hole 29 absorbs the difference in thermal expansion and contraction between the exhaust pipe 20r and the heat shield plate 26. The holes 28 and 29 are formed into elongated holes so that a bolt 38 can be detachably screwed into the female screw 25 through the holes 28 and 29. Note that except for the portions adjacent to the holes 28 and 29, the heat shield plate 26 is formed so that a predetermined gap exists between the heat shield plate 26 and the exhaust pipe 20r.

Furthermore, the heat shield plate 26 is formed with convex portions 30 extending in the longitudinal direction of the exhaust pipe 20r at predetermined intervals and oriented in the vehicle width direction and protruding downward, and a slit 31 is formed in the center of the convex portion 30. It is formed.

Therefore, the convex portion 30f near the cylinder 17r with the slit 31 as a boundary forms the exhaust gas collecting chamber 2.
The degree of curvature is smaller than that of the convex portion 30r located closer to the first side, so that the wind from the front caused by running flows to the rear of the heat shield plate 26 through the slit 31.

Further, a breather chamber 33 is formed in the upper part of the transmission case 32 of the engine 16.
An iron pipe 34 communicating with the rear exhaust pipe 3 projects upward from between the two rear exhaust pipes 20r, and a rubber breather pipe 35 is connected to the iron pipe 34.

Furthermore, a battery (not visible because it is obscured by the side cover 36) is disposed above the heat shield plate 26.

Note that 37 is a radiator for cooling the engine 16.

Since the illustrated embodiment is configured as described above, when the motorcycle 1 runs due to the operation of the front and rear V-type engines 16, the front exhaust pipe 20f is exposed forward and downward, and the front exhaust pipe 20f is exposed to the front and downward, and the wind that accompanies the running is sufficiently removed. The rear exhaust pipe 20r
Since it is located behind the engine 16 and does not receive enough wind from driving, it tends to be difficult to cool down.
Since the heat shield plate 6 is stretched, a part of the wind that flows along the side of the engine 16 due to the running is transferred to the heat shield plate 2.
6 and flowing along the lower surface of the heat shield plate 26, the rear exhaust pipe 20r and the heat shield plate 26 pass through the slit 31 and flow backward.
is cooled.

Furthermore, since the heat shield plate 26 is attached to the exhaust pipe 20r with a predetermined gap except for the vicinity of the holes 28 and 29, heating due to heat conduction from the exhaust pipe 20r is suppressed to a minimum. The heat shield plate 26 is not easily heated to a high temperature and can provide sufficient heat shielding effect to the battery above it.

Furthermore, since the heat shield plate 26 is stiffened by the convex portion 30 oriented in the width direction of the vehicle body, its natural frequency is greatly increased, and it resonates with the vibrations of the engine 16 and the vehicle body vibrations associated with driving. The anti-vibration properties are significantly improved.

Furthermore, since the heat shield plate 26 is not heated to a high temperature, the rubber breather pipe 35 disposed near the heat shield plate 26 is also less likely to be heated, and the durability of the pipe 35 is improved.

The present invention provides a heat shield that covers the upper surface of each exhaust pipe connected to the rear cylinder in a front and rear V-type motorcycle engine in which two exhaust pipes are arranged at least in the width direction of the vehicle body from a rear cylinder of the V-type engine. Concave or convex portions are formed on the plate at predetermined intervals along the length of the exhaust pipe and are oriented toward the width of the vehicle, and slits are provided in the concave and convex portions that are oriented toward the width of the vehicle. By flowing the accompanying wind, overheating of the heat shield plate can be prevented, and the heat of the exhaust pipe can be sufficiently blocked by the heat shield plate.

Further, in the present invention, the heat shield plate is reinforced by the uneven portion oriented in the width direction of the vehicle body, and its bending rigidity is improved, so that resonance with vibrations caused by the engine and driving can be prevented. I can do it.

[Brief explanation of drawings]

Fig. 1 is a side view of a motorcycle equipped with an embodiment of exhaust pipe heat shield plates for front and rear V-type engines according to the present invention, Fig. 2 is a perspective view of essential parts of the embodiment, and Fig. 3 is its rear view. 4 is a partially cutaway side view thereof, and FIG. 5 is a cross-sectional view taken along the - line in FIG. 3. 1... Motorcycle, 2... Frame, 3... Head pipe, 4... Main pipe, 5... Down tube, 6... Back stay, 7... Seat rail, 8... Handle steering device, 9... Front Fork, 10...Front wheel, 11...
Bottom plate, 12...Rear fork pivot, 13...Rear fork, 14...Rear wheel, 15...Rear suspension, 16...Front and rear V-type engine, 17...Cylinder, 18...Air cleaner, 19... Carburetor, 20...Exhaust pipe, 21...Exhaust collecting chamber, 22...Muffler, 23...Pillion step holder, 24
... Side cover, 25 ... Female screw, 26 ... Heat shield plate, 27 ... Both sides of heat shield plate, 28 ... Hole, 29
...Elongated hole, 30...Protrusion, 31...Slit, 3
2...Mission case, 33...Breather room,
34...Iron pipe, 35...Rubber breather pipe, 36...Side cover, 37...Radiator, 38...Bolt.

Claims (1)

[Scope of utility model registration request] In a front and rear V-type motorcycle engine in which two exhaust pipes are arranged at least in the vehicle width direction from a rear cylinder of the V-type engine, a heat shield plate covering the upper surface of each exhaust pipe connected to the rear cylinder is provided with the same A front and rear V for a motorcycle, characterized in that concave or convex portions are formed at predetermined intervals in the longitudinal direction of the exhaust pipe and are oriented in the vehicle width direction, and the convex and convex portions are provided with slits that are oriented in the vehicle body width direction. Type engine exhaust pipe heat shield.