JP2002046683A - Unit swing type engine suspending structure in motorcycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a unit wing type engine to be commonly used for various types of motorcycle, to improve assembly precision of the engine to a body side bracket and to simplify and facilitate assembly of the engine. SOLUTION: In a unit swing type engine suspending structure of the motorcycle, a body side bracket 20 is mounted to a cross pipe 13 of a body frame of the motorcycle provided with a unit swing type engine 15 projecting approximately horizontally a cylinder 16a from the crank case 16b, an engine side bracket 18 of a different body from the engine 15 is mounted in a lower front end of the crank case, the engine side bracket is connected with the body side bracket through a link 19, so that a front portion of the unit swing type engine is suspended in a body side, and that a baring 43 or a rubber bush mounted in a connected portion between the link 19 and the both brackets 18, 20 is pressed-in in the link 19.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension structure of a unit swing type engine in a motorcycle, and makes it easy and easy to apply the unit swing type engine to a motorcycle having a different model.

[0002]

2. Description of the Related Art A small scooter type motorcycle is provided with a unit swing type engine in which an engine and a transmission mechanism are integrated, and a front portion of the unit swing type engine is provided integrally with a crankcase. The vehicle is suspended by connecting the engine-side bracket to a vehicle-body-side bracket attached to a pair of left and right vehicle body frames via a link.

[0003]

However, in the conventional suspension structure, the engine side bracket is provided integrally with the crankcase of the unit swing type engine, so that the engine cannot be shared by a plurality of models. There was a problem. Further, in the conventional suspension structure, the rubber bushing that absorbs engine vibration and allows the swing of the unit swing type engine is press-fitted into each of the link side and the engine side. In addition to this, it has been difficult to keep the press-fitting accuracy of the rubber bush high. SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to limit the number of press-fit parts to one to reduce the number of assembling steps and to press-fit a bush or a bearing into the press-fit parts. The purpose of the present invention is to devise a suspension structure of the unit swing type engine so that the accuracy can be improved and the unit swing type engine can be easily and easily applied to motorcycles of different models.

[0004]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a motorcycle provided with a unit swing type engine having a cylinder projecting substantially horizontally from a crankcase. A vehicle-side bracket is attached to a cross pipe laid horizontally on a frame, and an engine-side bracket separate from the engine is detachably attached below a front end of the crankcase of the unit swing type engine, and the engine-side bracket is linked. The front part of the unit swing type engine is suspended on the vehicle body side by being connected to the vehicle body side bracket via the body, and a rubber bush is press-fitted into a front end connecting part of the link and connected to the vehicle body side bracket. Press the bearing or rubber bush into the rear end connection part That it has connected to the bracket and its features.

[0005]

Since the bush or the bearing is press-fitted to one part of only the link, the number of assembling steps is reduced and the press-fitting accuracy of the bush or the bearing is increased. Furthermore, since the engine side bracket is configured separately from the unit swing type engine and is detachably fixed to the crankcase, by selecting the engine side bracket according to the model of the motorcycle,
The subassembly including the engine side bracket and the unit swing type engine can be adapted to different types of motorcycles. Furthermore, since the vehicle-body-side bracket can be attached to an arbitrary position of a cross pipe that is bridged between the left and right main frames, the width dimension of the link connecting one end (front end) to the vehicle-body-side bracket is This can be set arbitrarily irrespective of the distance (width dimension) between the frames. As a result, the degree of freedom in the layout of parts around the link increases, and it is possible to cope with motorcycles of different models. Therefore, the same unit swing type engine can be shared by different types of motorcycles.

[0006]

An embodiment of the present invention will be described below with reference to the accompanying drawings. The schematic structure of the scooter type motorcycle 1 is shown in FIG.
5 and FIG. In FIG. 4, reference numeral 2 denotes a head pipe, in which a steering shaft 3 is rotatably inserted. A steering wheel 4 is attached to an upper portion of the steering shaft 3,
A front wheel 6 is rotatably supported at a lower portion via a front cushion 5. In FIG. 4, reference numeral 7 denotes a front fender, and reference numeral 8 denotes a front cowl.

From the lower part of the head pipe 2, one down tube 9 and two side tubes 10 extend rearward and downward. That is, the down tube 9 is provided at the center in the vehicle width direction, and one end (front end) thereof is inserted and welded to a joint 11 attached to a lower portion of the head pipe 2. And the down tube 9
Extends obliquely downward from the joint 11, and the rear end thereof is connected to the center of the cross pipe 13 described later in the width direction, as shown in FIG.

On the other hand, the two side tubes 10
Disposed on both sides of the down tube 9, one end (front end) of each
Are inserted and welded to the side of the joint 11. Then, each side tube 10 is connected to the joint 1
After extending substantially horizontally from 1 toward the outside and outside, it is bent at a substantially right angle and extends obliquely forward and downward, and is again bent at a substantially right angle and extends obliquely downward and rearward The main frame 12 is bent at an obtuse angle and extends obliquely upward and rearward, and the front end of the main frame 12 is inserted and bound to the rear end.

[0009] The pair of left and right main frames 12 extend obliquely upward toward the rear, bend and rise rapidly, and then bend again to extend obliquely upward toward the rear. As shown in FIG. 5, a cross pipe 13 is provided between the main frames 12, and a reinforcing sub-frame 14 is provided between the cross pipe 13 and each of the main frames 12.

The motorcycle 1 is mounted with a unit swing type engine 15 as a drive source. The engine body 16 of the unit swing type engine 15 has a cylinder 16a and a crankcase 16b which are inclined substantially horizontally. A transmission case 17 is integrally formed on one side of the crankcase 16b. One end of the unit swing type engine 15 is connected to a crankcase 16b.
A pair of left and right engine-side brackets 18 attached to the lower front end of the vehicle, and a link 19 pivotally attached to each bracket 18 are connected to and suspended from a vehicle-body-side bracket 20 attached to the cross pipe 13. I have. The other end (rear end) of the unit swing type engine 15 is connected to and suspended from a bracket 22 attached to the main frame 12 via a rear cushion 21. A rear wheel 23 is connected to an output shaft (rear axle) (not shown) that extends horizontally inward from the rear portion of the transmission case 17 of the unit swing type engine 15. The upper part of 23 is covered by a rear fender 24.

An air cleaner 25 is mounted on the transmission case 17 of the unit swing type engine 15 on the side of the rear fender 24, and a carburetor 26 is connected to the air cleaner 25. 27 is connected to the intake side of the cylinder 16a. On the other hand, as shown in FIG. 4, a storage box 29 for storing the helmet 28 above the unit swing type engine 15, a seat 30, and a fuel tank 31
The fuel tank 31 is provided with a rectangular frame-shaped support frame 32 extending rearward from the main frame 12.
Attached to. A license bracket 33 is attached below the fuel tank 31, and a portion below the seat 30 is covered with an exterior cover 34.

Here, the suspension structure of the unit swing type engine 15 according to the present invention will be described in detail with reference to FIGS. The engine side bracket 18 is formed separately from the unit swing type engine 15, and is provided as a pair of right and left as shown in FIG. 3, and both are connected and integrated by a pipe 35. Then, as shown in FIG. 3, each of the engine-side brackets 18
The unit swing type engine 15 is connected to the lower part of the front end of the transmission case 17 by a long bolt 37 inserted into the bolt 37 and the bolt hole 38. An exhaust pipe (not shown) extending from the cylinder 16a passes between the pair of left and right engine-side brackets 18. The exhaust pipe is protected by the engine-side bracket 18.

As shown in FIG. 3, a pair of left and right links 19 are provided, and both links 19 are connected and integrated by a pipe 40. Further, cylindrical bosses 41 and 42 are attached to the front and rear ends of each link 19. On the other hand, a pair of left and right vehicle body-side brackets 20 formed in a channel shape are connected to a lower portion of the cross pipe 13 which is bridged between the pair of left and right main frames 12. The link 19 is connected to the vehicle body side bracket 20 and the engine side bracket 18 by the following structure. That is, a rubber bush 43 is press-fitted into the boss 41 bonded to the front end of each link 19, and the front end of the link 19 is fitted into the vehicle body side bracket 20 as shown in FIG. 20 and a bolt 44 inserted through the rubber bush 43 from inside the vehicle body
And a nut 45 screwed to the bolt 44 to be connected to the vehicle body side bracket 20 and rotatably supported.
The rubber bush 43 is formed by baking a ring-shaped rubber on a metal inner and outer cylindrical tube, which is assembled to the link 19 by pressing the outer cylinder into the boss 41.

A bearing 46 is press-fitted into the boss 42 connected to the rear end of each link 19, and a sleeve 47 is provided between the pair of right and left engine-side brackets 18. Is passed. And
The rear end (the bearing 46) of the link 19 is positioned at a predetermined position on the sleeve 47 by a washer 48 abutting on both surfaces thereof and a circlip 49 fitted on the sleeve 47. The rear end of the link 19 has a bolt hole 50 formed in the engine-side bracket 18, a long through bolt 51 inserted into the sleeve 47, and a nut 52 screwed to the through bolt 51, so that the rear end of the link 19 can be mounted on the engine side. It is connected to a bracket 18 and is rotatably supported.

In the above-described suspension structure of the unit swing type engine 15 in front of the vehicle body, the vehicle body side bracket 20 can be attached to an arbitrary position of the cross pipe 13 laid between the pair of left and right main frames 12. The width dimension of the link 19 whose one end (front end) is connected to the vehicle body side bracket 20 can be set arbitrarily regardless of the distance (width dimension) between the main frames 12, and as a result, the link 19 The degree of freedom in the layout of the peripheral components is increased, and the components can be shared among various models.

Further, since the engine side bracket 18 is formed separately from the unit swing type engine 15 and is connected to the crankcase 16b, when the model is changed, the bracket 18 is replaced so that the unit swing type engine 15 is replaced. The engine 15 can be shared for each model, and a cost advantage can be obtained.
The cylinder 16a of the crankcase 16b shown in FIG.
There is also obtained an advantage that the machining of the mating surface 16b-1 is facilitated.

Further, in this embodiment, the press-fitting parts are limited to the link 19, and the rubber bush 43 and the bearing 46 are both press-fitted into the link 19, so that the man-hour for assembling the rubber bush 43 and the bearing 46 is reduced. In addition to the reduction, the accuracy of press-fitting these links 19 is improved.

In the present embodiment, as shown in FIG. 6, the rear cushion 21 is attached to the transmission case 17 via a bracket 53 formed separately from the transmission case 17. . In this embodiment, the bracket 53 is made of sheet metal,
The lower end of the rear cushion 21 is rotatably connected to the upper portion of the rear end of the transmission case 17 by the connecting member 5. Thus, as described above, the bracket 53
When the unit swing type engine 15 is shared by a plurality of models, the mounting position of the rear cushion 21 is optimized according to the dimensions of each model by replacing the bracket 53 when the unit swing type engine 15 is shared by a plurality of models. It becomes possible. In the suspension structure according to the present embodiment, the case where the rubber bush 43 is press-fitted into the link 19 has been described, but it goes without saying that the same effect can be obtained when the bearing 46 is press-fitted.

[0019]

As is apparent from the above description, according to the present invention, in a motorcycle equipped with a unit swing type engine, a cross pipe mounted on the left and right main frames of the body frame of the motorcycle is provided with a vehicle body side. Attach a bracket, attach an engine side bracket separate from the engine to the front of the unit swing type engine, and connect the engine side bracket to the vehicle body side bracket via a link, so that the front of the unit swing type engine A part is suspended on the vehicle body side, and a rubber bush is press-fitted into a front end connecting portion of the link and connected to a vehicle body side bracket, and a bearing or a rubber bush is press-fitted into a rear end connecting portion of the link and an engine side bracket is formed. , The number of press-fitting parts is one, and the number of assembly steps can be reduced. Both effects can be obtained that it is possible to increase the press-fitting accuracy of the bushes or bearings to the piezoelectric join the club article.

A unit swing type engine having a cylinder protruding substantially horizontally from a crankcase, wherein an engine-side bracket is integrally provided below a front end of the crankcase (for example, Japanese Patent Application Laid-Open No. 2-162186). Then, when the overlapping surface (joint surface) of the cylinder and the crankcase is cut, the workability is poor because the engine-side bracket is in the way. On the other hand, since the present invention has a structure in which a separate engine-side bracket is detachably attached to a lower portion of the front end of the crankcase, the engine is used for cutting the overlapping surface (joint surface) of the cylinder and the crankcase. There is no side bracket. Therefore, the engine side bracket does not hinder the cutting, and the machining efficiency is improved.

Further, since the engine side bracket is separate from the unit swing type engine and is detachably attached, an engine side bracket corresponding to the type of motorcycle can be used. Since the vehicle-body-side bracket can be attached to an arbitrary position of the cross pipe laid horizontally between the left and right main frames, the width dimension of the link connecting one end (the front end) to the vehicle-body-side bracket is between the main frames. It can be set arbitrarily irrespective of the distance (width dimension). As a result, the degree of freedom in the layout of parts around the link is increased, and it is possible to cope with various motorcycles.
The same unit swing type engine can be used for various motorcycles. Therefore, the cost of the unit swing type engine is reduced.

[Brief description of the drawings]

FIG. 1 is a cutaway side view of a suspension unit at the front of a unit swing type engine.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an exploded perspective view of a suspension unit at the front of a unit swing type engine.

FIG. 4 is a side view of the scooter type motorcycle.

FIG. 5 is a partial plan view of the scooter type motorcycle.

FIG. 6 is a side view of a suspension unit at the rear of the unit swing type engine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Scooter type motorcycle 2 ... Head pipe 12 ... Main frame 13 ... Cross pipe 15 ... Unit swing type engine 18 ... Engine side bracket 19 ... Link 20 ... Body side bracket 43 ・ ・ ・ Rubber bush 46 ・ ・ ・ Bearing

Continued on the front page (72) Inventor Shigeru Sugiyama 2500 Shinkai, Iwata-shi, Shizuoka Prefecture Yamaha Motor Co., Ltd. F-term (reference) 3D011 AF04 AG01 AH02 AK03 AK15 AL21

Claims (1)

[Claims] 1. A motorcycle provided with a unit swing type engine having a cylinder projecting substantially horizontally from a crankcase, wherein a vehicle body side bracket is attached to a cross pipe which is laid across left and right main frames of a body frame of the motorcycle. An engine-side bracket separate from the engine is detachably mounted below the front end of the crankcase of the unit-swing type engine, and the engine-side bracket is connected to the vehicle-body-side bracket via a link, thereby unit swinging. A front portion of the engine is suspended on the vehicle body side, and a rubber bush is press-fitted into a front end connecting portion of the link and connected to a vehicle body side bracket, and a bearing or a rubber bush is press-fitted into a rear end connecting portion of the link. Automatic Suspension structure of the unit swing type engine in a vehicle.