JPH02158484A - Frame for scooter - Google Patents

Abstract

PURPOSE:To concentrate a load support part to the central part of a frame, to improve rigidity, and to reduce the weight of a frame by a method wherein a down tube, a body tube, a frame leg, and a stopper pipe are intercoupled in respective specified states to form a frame. CONSTITUTION:The front end of a body tube 10 is welded to the lower end of a down tube 9 extended downward from a head pipe 8. A frame leg 11 is welded to the lower part of the body tube 10, and the frame leg 11 is coupled to a stopper plate 12. A boss 15 is mounted to the frame leg 11, and a front lower end boss 5 of a power unit 1 is pivotally mounted to the frame leg 11 through a link 17. The lower end of a cushion unit 18 is pivotally mounted to a bracket 14 through which body tubes 10 are intercoupled. A lever 19 pivotally mounted to the upper end of the cushion unit 18 is pivotally mounted to the boss 15, and is pivotally mounted to a front upper boss 5 of a power unit 1 through a rod 20.

Description

[Detailed description of the invention] [Industrial application field] TECHNICAL FIELD This invention relates to improvements in scooter frames.

[Conventional technology and its problems]

As shown in Fig. 5, a scooter generally has a rear extension B integrally provided on one side of an engine case A to house a transmission device, and a rear wheel C rotatably supported at the rear of the rear extension B. A power unit D is used. The frame E is made of a steel pipe or the like, and a front lower end boss H of the power unit D is pivoted to a frame leg F provided at the lower part of the frame E via a link G. Also, the upper end of the cushion unit J, which is pivoted on the upper side of the rear extension part B of the power unit D, is attached to a bracket K provided at the rear of the frame E.
It is attached to the shaft. In this way, the cushion unit J expands and contracts, the power unit D swings, and the rear wheel C is cushioned.

For this reason, the load-bearing parts are divided into the frame legs F of the frame E and the rear bracket, and rigidity is required between them as well, which inconveniently increases the weight of the frame E. For example, Japanese Patent Application Laid-Open No. 58-49589,
See Japanese Patent Application Laid-open No. 57-967.

[Purpose of the invention]

This invention aims to provide a lightweight and inexpensive scooter frame that can strengthen the part that receives the load of the power unit by concentrating it in the center of the frame, has good cushioning performance, and reduces the load burden on the frame contact parts. purpose.

[Structure of the invention]

The present invention will be explained below with reference to embodiments shown in FIGS. 1 to 4.

In the power unit 1, a rear extension part 3 is integrally provided on one side of a front engine case 2, a transmission device is built in, and a rear wheel 4 is rotatably supported at the rear part of the rear extension part 3. be. Bosses 5 are provided at the top and bottom of the center of the engine case 2 at the front of the power unit 1, projecting forward. The frame 6 is attached to the lower end of the down tube 9 which is lowered from the head pipe 8 to which the front fork 7 is attached.
Weld the paired body dups 1o. body dupe 1
A frame leg 11 is welded to the lower side of the front part of 0, and a stopper plate 12 is welded to connect the left and right frame legs 11. The left and right body dups 10 are connected by a bridge 13 at the front side of the frame leg 11 and at the rear upper side. A bracket 14 is welded to the front bridge 13, and the rear end of the bracket 14 is aligned and welded to the stopper plate 12. A boss 15 is welded to the rear bridge 13. A seat rail 16 is welded to the rear portions of the left and right body tubes 1o. The seat rail 16 may be a thin steel pipe for light loads. A link 17 is inserted into the frame leg 11 and pivoted to the stopper plate 12 so as to swing slightly. Then, the lower boss 5 of the power unit 1 is pivoted to the rear end of the link 17. The cushion unit 18 is made of a cushion spring and a damper, and has a lower end pivoted to the bracket 14 and a lever 19 pivoted to the upper end. The lever 19 is pivotably attached to the boss 15, and has a rod 20 pivoted to the rear thereof. The rear end of the rod 20 is pivoted to the upper boss 5 of the power unit 1.

[Action of the invention]

When the rear wheel 4 receives an impact from the road surface, the power unit 1 pivots around the lower boss 5 and the link 17, rotates the lever 19 with the rod 2o, retracts the cushion unit 18, and swings. Move and cushion. The weight that suspends the power unit 1 is the left and right body tube 1.
The left and right frame legs 11 are connected by a stopper plate 12, and the stopper plate 12 and the bracket 14 are also connected, so that the rigidity of this part can be increased. Furthermore, the load applied to the rear seat rail 16 can be reduced, resulting in greater weight reduction. The cushion unit 18 is pushed down straight, without twisting, and the cushioning performance can be improved.

(Effects of the Invention) As explained above, in the present invention, the front ends of the pair of left and right body tubes are welded to the lower ends of the down tubes lowered from the head pipe, and the frame legs are welded to the lower parts of the body tubes. Connect the left and right frame legs with a stopper plate, provide a bridge connecting the left and right body tubes on the front side of the stopper plate, weld the rear end of the bracket welded to the bridge to the stopper plate, and connect the left and right frame legs to the rear upper side of the frame leg. A boss is provided on the bridge provided, the front lower end boss of the power unit is pivoted to the frame leg via a link, the lower end of the cushion unit is pivoted to the bracket, and the lever pivoted to the upper end of the cushion unit is attached to the boss of the bridge. In addition to being pivoted to the front upper boss of the power unit via a rod, the load that suspends the power unit can be concentrated between the front and rear bridges of the left and right body tubes of the frame. The left and right frame rail lugs, stopper plates, and brackets are connected in series to increase rigidity.In this way, the load on the rear seat rails, etc. can be reduced, making it possible to reduce weight. Moreover, the cushion unit can be expanded and contracted straight in the center without twisting, and the cushioning performance can be improved.

14...Bracket, 15...Boss, 17...Link, 18...Cushion unit, 19...Lever 20...Rod.

Claims (1)

[Claims] Weld the front ends of the pair of left and right body tubes to the lower end of the down tube lowered from the head pipe, weld the frame legs to the bottom of the body tube, connect the left and right frame legs with a stopper plate, and then A bridge connecting the left and right body tubes is provided on the front side, the rear end of the bracket welded to the bridge is welded to the stopper plate, a boss is provided on the bridge provided on the rear upper side of the frame leg, and a link is attached to the frame leg. The front lower end boss of the power unit is pivoted, the lower end of the cushion unit is pivoted to the bracket, the lever pivoted to the upper end of the cushion unit is pivoted to the bridge boss, and the lever is attached to the front upper boss of the power unit via the rod. A scooter frame characterized by being attached to the shaft.