JPS62198578A - Air cleaner for motorcycle - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an air cleaner installed in a motorcycle.

[Prior art]

As a body frame for a motorcycle, the main frame has a hollow rectangular cross section, and is formed in a so-called delta box shape, which is wide at the front end in the longitudinal direction and becomes narrower toward the rear. A device with a pair of left and right is attracting attention.

On the other hand, since an air purifier installed in a motorcycle needs to also have an intake noise muffling function, it has been found that a larger volume is preferable. However, compared to four-wheeled vehicles, motorcycles have less space for installing accessory equipment, so there is the problem that the vehicle body must be made larger in order to increase the volume of the air purifier, as mentioned above. This causes an increase in weight and cost.

[Purpose of the invention]

An object of the present invention is to provide an air purifier for a motorcycle that utilizes the above-mentioned delta box type main frame and has a large volume without constricting the installation space for other equipment.

[Structure of the invention]

To achieve the above object, the present invention provides a motorcycle equipped with a pair of left and right main frames each having a hollow rectangular cross-section, wide at the front end in the longitudinal direction, and narrowing toward the rear. It is characterized in that an intake hole is provided in the outer wall of the engine and that penetrates into the hollow part, and a filtration element is provided in the hollow part, and communication is made through the filtration element to the intake system of the engine.

〔Example〕

In the motorcycle shown in FIG. 3, 1 is a steering shaft tube, 2 is a main frame, 3 is a backstay, and 4 is a down tube that connects the lower part of the front end of the main frame 2 and the lower part of the backstay 3. Reference numeral 5 denotes an engine mounted on a vehicle body frame made up of these members. A carburetor 7 is attached to the intake system of the engine 5, and an exhaust pipe 8 is attached to the exhaust system.

As shown in FIGS. 1 and 2, a pair of left and right main frames 2.2 are provided, each having a front end welded to the rear of the steering shaft tube 1 and extending obliquely outward, and further curved and extending rearward. There is. The main frame 2 has a hollow rectangular cross section by welding a half-split outer plate part 2a and an inner plate part 2b, and the front end in the longitudinal direction is the length of the steering shaft tube 1. It is equally wide at the front and narrows toward the rear, creating a so-called delta box shape. Further, the front end portions of the left and right inner plate portions 2b, 2b are integrally connected to form a saddle shape, and a delta-shaped space 6d is formed therein.

The outer wall forming the inner plate part 2 has a large number of intake holes 8 on the inner surface. -...-98 is provided so as to penetrate into the hollow part 6. Furthermore, a large opening 9 is provided corresponding to the delta-shaped space 6d in front thereof, and a filtration element 10 is attached to the opening 9 via a retaining plate 11. This holding plate 11 is provided with an air supply pipe 12, and this air supply pipe 12 communicates with the carburetor 7. Further, a reinforcing plate 13 is provided in the delta-shaped space 6d.

When the engine 4 is operated in the above-mentioned motorcycle,
Intake hole 8 of main frame 2 for outside air. -..., 8 is inhaled into the hollow part 6, and further passes through the filtration element 10 installed in the delta-shaped space 6d at the front end, using the hollow part 6 as an intake passage, and is removed by this filtration element 10. It then reaches the carburetor 7, where it becomes a mixture with fuel and is supplied to the engine 4.

Since the filtration element 10 is installed in the large-volume hollow part 6 within the main frame 2, the space for other accessory equipment installed in the vehicle body frame is not narrowed, and the air purifier does not become large. This eliminates the need to enlarge the vehicle body.

Further, when the filter element 10 is installed in the delta-shaped space 6d as in the above embodiment, the delta-shaped space 6d is the position where the cross-sectional area is the largest, so the flow velocity of the intake air flow is slowed down in this part. , dust separation can be advantageous.

Further, as described above, when the outside air is drawn into the hollow portion 6 through the intake hole 8, intake noise is generated, but the intake noise is attenuated while bouncing off the inner wall within the main frame 2, so that it is muffled. That is, the hollow part 6 with a large volume constitutes an intake silencer, and the hollow part 6 is long in the longitudinal direction (
It has a large volume, a large cross-sectional area on the front end side, and a shape that gradually decreases toward the rear, so it can be effective in attenuating frequencies over an extremely wide range.

Furthermore, since the intake holes 8 in the above embodiment are provided on the inner surface of the outer wall of the main frame 2, they are difficult to see from the outside, thereby improving the appearance. In addition, it is possible to reduce suction of water and dust, and it is also advantageous for separation. From this point of view, the intake hole 8 may be provided on the lower surface of the main frame 2.

〔Effect of the invention〕

As described above, the present invention provides a motorcycle equipped with a pair of left and right main frames each having a hollow rectangular cross section, wide at the front end in the longitudinal direction, and narrowing toward the rear. An intake hole is provided in the outer wall that penetrates into the hollow part, and a filtration element is provided in the hollow part, and the air purifier is connected to the engine's intake system through this filtration element. It is in a set state. Therefore, even though the air purifier has a large capacity, a special space is not required for installation of the air purifier, and the installation space for other accessory equipment is not narrowed. Furthermore, the hollow section is long in the longitudinal direction and has a large volume, and its cross-sectional area gradually decreases from the front end, so it is effective at attenuating frequencies over a wide range and also exhibits a high silencing effect. I can do it.

[Brief explanation of drawings]

Figure 1 shows the main frame that constitutes the air purifier of the present invention.
2 is a cross-sectional view taken along arrow I-1 in Figure 2, Figure 2 is a cross-sectional view of the main frame taken along arrows ■-■ in Figure 1, and Figure 3 is a side view of a motorcycle equipped with the main frame. It is a diagram. 2- Main frame, 5- Engine, 6-
- hollow part, 7- vaporizer, 8-.- suction hole, 1o.
-・Filtration filter.

Claims (2)

[Claims] (1) In a motorcycle equipped with a pair of left and right main frames each having a hollow rectangular cross-section, wide at the front end in the longitudinal direction, and narrowing toward the rear, a hollow section is formed on the outer wall of the main frame. 1. An air purifier for a motorcycle, characterized in that an air purifier is provided with a penetrating intake hole, a filter element is provided in the hollow part of the air intake hole, and the air cleaner is connected to an intake system of an engine via the filter element. (2) The air cleaner for a motorcycle according to claim 1, wherein the filtration element is installed in a delta-shaped space where the front end portions of both the left and right main frames meet.