JPH0764293B2 - Saddle type vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION A. Purpose of the Invention (1) Field of Industrial Application The present invention is a straddle-type vehicle mainly used for traveling on a wasteland,
In particular, a frame having a main tube that inclines rearward and downward from the support portion of the steering shaft, and a seat rail that extends substantially horizontally rearward from the main tube, and an engine supported by the frame below the main tube, The present invention relates to a straddle-type vehicle that includes a fuel tank installed on a main tube and a straddle-type seat installed on a seat rail.

(2) Conventional Technology This type of saddle riding type vehicle is already known as disclosed in, for example, Japanese Utility Model Publication No. 58-1098.

(3) Problems to be Solved by the Invention In a conventional saddle-ride type vehicle, since only one main tube of the frame is arranged along the longitudinal centerline of the vehicle, the main tube is connected to the engine below. In order to avoid the interference, the vehicle must be placed at a relatively high position, and as a result, the position of the fuel tank on the main tube also rises and the center of gravity of the vehicle tends to increase.

The present invention has been made in view of the above point, and enables the fuel tank to be placed close to the engine without being hindered by the main tube to lower the center of gravity, and the main tube is used to remove air with little dust from the engine. An object of the present invention is to provide the saddle-ride type vehicle that can be smoothly introduced into an air cleaner.

B. Configuration of the Invention (1) Means for Solving the Problems In order to achieve the above object, according to the present invention, the main tube is located on both left and right sides of the engine head when viewed from the left and right outer sides of the vehicle. A pair of left and right are arranged so as to pass through, respectively, and the front ends of the main tubes are opened to the atmosphere, and an air cleaner is connected to the rear ends of the main tubes to introduce outside air through the main tubes. , Is connected to the rear end of the intake pipe extending to the rear of the engine and is disposed below the straddle-type seat.

(2) Action The fuel tank is installed on a pair of left and right main tubes that pass through the left and right sides of the engine head as viewed from the outside of the vehicle, and the air cleaner also has an intake pipe that extends to the rear of the engine. The fuel tank is connected to the rear end of the main tube and communicates with the rear end of the main tube because it is located below the straddle seat on the seat rail and communicates with the rear end of the main tube. It is possible to arrange the bottom surface close to the engine, which lowers the installation position of the fuel tank and lowers the center of gravity of the vehicle.

Moreover, since both main tubes communicate between the front upper part of the vehicle with less dust and the air cleaner behind the engine, it is possible to introduce clean outside air into the air cleaner to reduce the filtration load, and to use a dedicated air cleaner. Since the introduction pipe is not required, the structure is simplified.
The total intake resistance of the main tube of the book is small, so that the output of the engine is improved.

(3) Embodiment An embodiment of the present invention will be described below with reference to the drawings. First, in FIG. 1 and FIG. 2, a wastewater traveling bucket truck 1 includes a pair of left and right front wheels on a front portion and a rear portion of a frame 2, respectively. The fuel tank 5 and the straddle-type seat 6 are arranged in the front and back on the upper portion of the frame 2 while the 3, 3 and 4, 4 are suspended, thereby forming a straddle type.

The frame 2 includes a pair of right and left rectangular tube-shaped main tubes 7 and 7, which incline at a gentle slope in the rearward direction, and these main tubes 7 and 7.
A pair of left and right front tubes 8,8 extending from the lower surface of the front end of the front tube in a steep slope, and a pair of left and right front tubes 8,8 extending from the rear surface of the upper ends of the front tubes in a steep slope to the rear. Down tubes 9,9, a pair of left and right center tubes 10,10 extending downward from the rear of the main tubes 7,7,
A pair of left and right seat rails 11,11 that extend rearward from the middle portion of the main tubes 7,7 toward the rear substantially horizontally, and connect the rear ends of these seat rails 11,11 and the middle portions of the center tubes 10,10. Left and right stays 12, 12, center tube 1
A pair of left and right main tubes 13 and 13 connecting the lower ends of 0 and 10 and the lower ends of the down tubes 9 and 9 and extending forward from the down tubes 9 and 9, and these main lower tubes 13 and 13.
The main element is a pair of left and right sub-lower tubes 14 and 14 that connect the down tubes 9 and 9 to the front tubes 8 and 8 above, and the front ends of the main tubes 7 and 7 are box-shaped gussets 1.
5, the rear ends of the seat rails 11 and 11 are connected to each other via a cross member 16. The front ends of the main lower tubes 13, 13 are connected to each other via a cross member 17, and the front ends of the sub lower tubes 14, 14 are connected to each other via a cross member 18.

The front of the gusset 15 has a steering shaft 19 for the front wheels 3, 3.
A bearing 20 for supporting the steering shaft is provided, and a rod-shaped steering handle 21 is attached to the upper end of the steering shaft 19.

The main tubes 7, 7, the down tubes 9, 9, the main lower tubes 13, 13 and the center tubes 10, 10 constitute a pair of left and right cradle structures 22, 22 between which an engine 23 with a transmission is installed. It is arranged. And the crankcase 24 of this engine 23 has a down tube 9,
9, main lower tube 13,13 and center tube 10,10
To the brackets 26, 27, 28 protruding from the
It is fixed. In this way, the engine 23 is a double cradle structure.
It is supported by 22,22, and both 22 and 22 are connected to each other. At that time, the left and right main tubes 7, 7 are the engine 23
The cylinder heads 25 are arranged on both left and right sides of the cylinder head 25 so that the pair of left and right main tubes 7, 7
Is arranged so as to pass through both the left and right sides of the head of the engine 23 (that is, the cylinder head a25) when viewed from the left and right outer sides of the vehicle. The power of the engine 23 is transmitted to a common axle 40 of both rear wheels 4, 4 via a chain drive device 39.

An intake pipe 32 extending rearward through a carburetor 30 is connected to the rear surface of the cylinder head 25 of the engine 23, and an exhaust pipe 31 is connected to the front surface of the head 25. An air cleaner 33 is connected to the end portion, and a muffler 34 is connected to the rear end portion of the exhaust pipe 31.

The fuel tank 5 is on the main tubes 7 and 7 so as to cover the engine 23 and the carburetor 30 from above, and the seat 6 connected to the rear end of the fuel tank 5 is the seat rail 1
Each of them is detachably mounted on 1,11. The air cleaner 33 is arranged in the frame 2 immediately below the seat 6, and the muffler 34 is arranged on one side of the air cleaner 33 with the stay 12 interposed therebetween.

A bracket 35, on the lower front surface of the center tube 10, 10.
A rear fork 36 that supports the rear wheels 4, 4 at the rear end is pivotally supported 37 so as to be vertically swingable. Between the rear fork 36 and the frame 2, the rear fork 36
A hydraulic rear damper 38 for damping vertical swinging of the rear damper 38 is provided, and the rear damper 38 has a built-in suspension spring that repels the rear fork 36 downward. The mounting structure of the rear damper 38 to the frame 2 will be described later.

The air cleaner 33 is adapted to introduce the outside air from the upper front portion of the vehicle 1 through the left and right main tubes 7, 7 and the gusset 15.

That is, as shown in FIGS. 1 to 4, the lower surface of the gusset 15 is continuously provided with an outside air intake box 41 whose front and rear ends are open, and has a large diameter which communicates with the outside air intake box 41. A through hole 42 is bored. Also, install the gusset 15 on the left and right main tubes 7,
Through holes 43, 43 for communicating with 7 are formed in the side walls of the main tubes 7, 7. On the other hand, as shown in FIG. 5 and FIG.
Connection tubes 44, 44 having a circular cross section are bulged at the rear ends of the main tubes 7, 7, and these connection tubes 44, 44 are a pair of left and right inlet tubes projecting from the front surface of the cleaner case 45 of the air cleaner 33. It is tightly fitted into the inside of 46, 46 via the elastic seal cylinders 47, 47, respectively.

The elastic seal cylinder 47 is fitted on the outer peripheral surfaces of the connecting cylinder 44 and the inlet cylinder 46 outside the fitting portion, and the bands 48, 49 are provided.
Is tightened by. In this way, the cleaner case 45 is elastically supported at its front end by the left and right main tubes 7, 7.

On the other hand, in order to support the rear end of the cleaner case 45, a support pin 50 is provided on the back surface of the cleaner case 45 and the support pin 50 is provided.
A bracket 52, which supports the bearing via an elastic bush 51, is fixed to the cross member 16 with a bolt 53 and a nut 54.

Further, an outlet tube 55 is provided on the front surface of the cleaner case 45, the upstream end of the intake pipe 32 is fitted to the outer circumference of the outlet tube 55, and a tightening band 56 is provided on the outer circumference.

The outlet cylinder 55 also protrudes inward of the cleaner case 45, and a cleaner element 57 is attached to the inwardly protruding end thereof.

The upper surface of the cleaner case 45 is open, and a lid plate 58 that closes the open surface is locked to the cleaner case 45 by a plurality of locking members 59, 59. Thus, the cleaner element
When attaching or detaching 57, first attach the seat 6 to the seat rails 11 and 1.
The cleaner element 57 can be easily attached and detached by removing it from 1, and then opening the lid plate 58.

7 and 8 show a mounting structure of the rear damper 38 to the frame 2. Main tube 7,7 of frame 2
The seat rails 11 and 11 located above the left and right seat rails 11 and 11 have a pair of left and right brackets 60 and 6 whose central portion is curved inward of the frame 2.
Both ends of 0 are welded respectively, and these brackets 60,
Bosses 61 and 61 'are welded to the central portion of 60, respectively. Between the bosses 61, 61 ', an eyeball portion 62 for mounting the upper end of the rear damper 38 is arranged, and the bosses 61, 61' are connected to each other by a bolt 63 penetrating and supporting the eyeball portion 62.

The operation of this embodiment will be described below.

While the buggy vehicle 1 is running, a part of the air passing through the outside air intake box 41 flows into the gusset 15 through the through hole 42, and is further diverted from the through holes 43 and 43 into the left and right main tubes 7 and 7, and the inlet tube After flowing into the cleaner case 45 of the 46, 46 air cleaner 33 and being filtered by the cleaner element 57, it is guided to the carburetor 30 via the outlet cylinder 55 and the intake pipe 32, and is sucked into the engine 23 as a mixture.

In this way, the intake air of the engine 23 is taken in from the upper front part of the buggy car 1 with less dust by using the outside air intake box 41, the gusset 15 and the main tubes 7, 7, so that a relatively clean air is supplied to the air cleaner 33. Can be introduced to
The filtration load on the air cleaner 33 is reduced.

Moreover, since the front and rear ends of the outside air intake box 41 are open so that the traveling wind can pass through, the dirt, snow, and the like that enter the outside air intake box 41 are blown backward by the traveling wind, and It does not collect in the intake box 41.

Also, a pair of main tubes used as air introduction tubes
Since 7 and 7 have low total intake resistance, they can contribute to improving the output of the engine 23.

Further, the pair of main tubes 7, 7 are arranged so as to sandwich the cylinder head 25 of the engine 23 from the left and right, and the air cleaner 33 is provided on the rear end portion of the intake pipe 32 extending rearward of the engine 23. The main tubes 7 and 7 are connected to each other and arranged below the straddle type seat 6 on the seat rail 11.
Since it communicates with the rear end, it is possible to arrange the bottom surface of the fuel tank 5 as close to the engine 23 as possible without being hindered by any of the main tubes 7, 7 and the air cleaner 33. The installation position is lowered, and the center of gravity of the vehicle can be lowered.

Furthermore, an air cleaner 3 is attached to the rear end of the main tubes 7, 7.
Since the three inlet cylinders 46, 46 are fitted via the elastic seal cylinders 47, 47, the air cleaner 33 is elastically supported by the main tubes 7, 7, and the support structure of the air cleaner 33 is simplified. .

C. Effects of the Invention As described above, according to the present invention, the fuel tank is installed on the pair of left and right main tubes that pass through the left and right sides of the engine head as viewed from the outside of the vehicle, and the air cleaner is Since it is connected to the rear end of the intake pipe that extends rearward and is disposed below the straddle-type seat on the seat rail, the engine on the bottom of the fuel tank is not blocked by either the main tube or the air cleaner. It is possible to place the fuel tank closer to the vehicle, and the fuel tank installation position is lowered accordingly, and the center of gravity of the vehicle can be lowered.

Moreover, the front ends of the pair of left and right main tubes are opened to the atmosphere, and the rear ends of the main tubes are communicated with the air cleaner so that both main tubes can be used as air introduction pipes. It is possible to reduce the filtration load of the air cleaner, improve the engine output by reducing the total intake resistance, and simplify the structure.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a side view of a four-wheel buggy vehicle, FIG. 2 is a plan view thereof, and FIG. 3 is an enlarged sectional view taken along line III-III of FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3, FIG. 5 is an enlarged sectional view taken along the line VV in FIG. 2, FIG. 6 is a partially longitudinal plan view of FIG. 5, and FIG. FIG. 8 is an enlarged side view around the rear damper in the figure, and FIG. 8 is a sectional view taken along the line VIII-VIII in FIG. 1 ... four-wheel buggy as a saddle-type vehicle, 2 ... frame, 5 ... fuel tank, 6 ... seat, 7 ... main tube, 11 ... seat rail, 19 ... steering axis, 23 …… Engine, 24 …… Crankcase, 25 …… Cylinder head, 33 …… Air cleaner

Claims (1)

[Claims] 1. A main tube (7) inclined rearward and downward from a support portion of a steering shaft (19), and a seat rail (11) extending rearward from the main tube (7) substantially horizontally.
(2) having an engine, an engine (23) supported by the frame (2) below the main tube (7), and a fuel tank (5) installed on the main tube (7)
In a straddle-type vehicle including a seat and a straddle-type seat (6) installed on a seat rail (11), the main tube (7) is a head part of the engine (23) when viewed from the left and right outside of the vehicle. A pair of left and right are provided so as to respectively pass on both left and right sides of the main tube (7), and front ends of the main tubes (7) are opened to the atmosphere,
An air cleaner (33) is connected to the rear end portion of the main tube (7) to introduce outside air through the inside, and the air cleaner (33) is connected to an intake pipe (32) extending rearward of the engine (23). A straddle-type vehicle, which is connected to a rear end portion and is arranged below the straddle-type seat (6).