Title of Invention

BODY FRAME FOR MOTORCYCLE

Abstract 1. A body frame for a motorcycle, including a first frame (23), a second frame (24) and a third frame (22), a second frame (24) is fastened to a first frame (23) by means of bolts and nuts, a third frame (22) is fastened to a second frame (24) by means of bolts and nuts, said first frame (22) is formed by casting and integrally has a head pipe (25) for steerably supporting a front wheel (WR), down frame (26) extending rearwardly, downwardly from said head pipe (25), and floor supporting frames (271 272) extending rearwardly from the lower end of said down frame (26) and disposed under a step floor (41b); said second frame (24), which swingably supports a power unit (P) and is connected to the upper end of a rear cushion (33), is formed by casting and is fastened to the rear ends of said floor supporting frames (271, 272).
Full Text


FORM 2
THE PATENTS ACT 1970
[39 OF 1970]
PROVISIONAL/COMPLETE SPECIFICATION
[See Section 10]
And Rule 13]
"BODY FRAME FOR MOTORCYCLE"

HONDA GIKEN KOGYO KABUSHIKI KAISHA, a corporation of Japan, having a place of business at 1-1, Minamiaoyama 2-chome, Minato-ku, Tokyo, Japan
The following specification particularly describes the nature of tfte invention and the manner in which it is to be performed :-

3 5 4|MUM/2000




17 APR 2000 Granted
Original

[Detailed Description of the Invention]
[0001]
[Technical Field to Which the Invention Pertains]
The present invention relates to a body frame for a motorcycle, and particularly to a body frame suitable for a scooter-type vehicle. [0002]
[Prior Art]
As known typically from Japanese Patent Laid-open Nos. Hei 1-311975 and Hei 7-156852, a body frame for a motorcycle is generally, integrally formed by welding steel pipes or by casting a metal material. [0003]
[Problem to be Solved by the Invention]
The above-described integrally formed body frame in the prior art has the following problem: namely, since it is difficult to convert part of the body frame to the corresponding part of a body frame of a different motorcycle because of the limitation in size and an external shape of the body frame, the body frame must be designed for each kind of motorcycle. In particular, where the body frame is formed by casting, a mold used for casting must be changed for every kind of motorcycle, with a result that it takes a lot of cost to design and produce a body frame. Further, since the body frame is integrally formed, a plurality of parts are sequentially mounted to the body frame upon assembly of a motorcycle.


As a result, an assembling efficiency becomes low. [0004]
In view of the foregoing, the present invention has been made, and an object of the present invention is to provide a body frame for a motorcycle, which is capable of converting, upon partial change of a different body frame, part of the body frame to the corresponding part of the different body frame thereby reducing the design and production costs, and also improving an assembling efficiency of the motorcycle. [0005]
[Means for Solving the Problem]
To achieve the above object, according to an invention described in claim 1, there is provided a body frame for a motorcycle, including a first frame, a second frame, and a third frame, those are fastened to each other, wherein at least one of the first, second, and third frames is produced by die-forming. [0006]
With this configuration, since at least one of the first, second and third frames constituting the body frame is produced by die-forming, such a frame can be shared/converted among various kinds of motorcycles made different from each other by changing part of each body frame, with a result that it is possible to reduce the


design and production costs of a body frame due to the model change of body frame. Further, since each of the first, second and third frames can be modularized, a motorcycle can be assembled by mounting parts to each modularized frame and then assembling these three modules having been sub-assembled to each other. As a result, it is possible to improve the assembling efficiency of the motorcycle.
According to the present invention there is provided a body frame for a motorcycle, including a first frame, a second frame and a third frame,
a second frame is fastened to a first frame by means of bolts and nuts, a third frame is fastened to a second frame by means of bolts and nuts,
said first frame is formed by casting and integrally has a head pipe for steerably supporting a front wheel (WR), down frame extending rearwardly, downwardly from said head pipe, and floor supporting frames extending rearwardly from the lower end of said down frame and disposed under a step floor;
said second frame, which swingably supports a power unit (P) and is connected to the upper end of a rear cushion, is formed by casting and is fastened to the rear ends of said floor supporting frames.
With this configuration, it is possible to reduce


the design and production costs due to the model change of body frame of the scooter-type motorcycle and to improve the assembling efficiency of the motorcycle. Also, since each of the first and second frames as main portions of the body frame of the scooter-type motorcycle is formed by casting, it is possible to further reduce the design and product costs by sharing either the first frame or the second frame among various kinds of scooter-type motorcycles. The third frame at the rear portion of the body frame, which is relatively low in design and production costs, can be easily formed by working metal pipes in accordance with the model change of body frame of the motorcycle. [0009]
[Mode for Carrying Out the Invention]
Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings. [Brief Description of the brawings] [Fig. 1]
A side view of a scooter-type vehicle. [Fig. 2]
An enlarged side view of a front portion of the scooter-type vehicle. [Fig. 3]
An enlarged side view of a rear portion of the scooter-type vehicle.

[Fig. 4]
A view, seen in the direction shown by an arrow of Fig. 3, of the rear portion of the scooter-type vehicle from which a luggage box and a fuel tank are omitted. [Fig- 5]
A perspective view of a front frame and a rear frame which are separated from each other. [Fig. 6]
An enlarged side view of the front frame. [Fig. 7]
A view seen in the direction shown by an arrow 7 Fig. 6. [Fig. 8]
An enlarged sectional view taken on line 8-8 of 6.
[Fig. 9]
An enlarged sectional view taken on line 9-9 of 7.
[Fig. 10]
An enlarged sectional view taken on line 10-10 o Fig. 7. [Fig. 11]
An enlarged side view of the rear frame. [Fig. 12]

An enlarged sectional view seen in the direction shown by an arrow 12 of Fig. 11. [Fig. 13]
An enlarged sectional view taken on line 13-13 of Fig. 12. [Fig. 14]
A side view, with parts partially cutaway, showing a portion for swingably supporting an engine on a body frame.
[Fig. 15]
A sectional view taken on line 15-15 of Fig. 14. [Fig. 16] A side view showing a portion for mounting a rear cushion unit to the body frame.
[Fig. 17]
A sectional view taken on line 17-17 of Fig. 16. [Fig. 18]
A sectional view taken on line 18-18 of Fig. 17. [Fig. 19]
A side view of a sub-frame. [Fig. 20]
A view seen in the direction shown by an arrow 20 of Fig. 19. [Fig. 21]
An enlarged view seen in the direction shown by an


arrow 21 of Fig. 1. [Fig. 22]
A view seen in the direction shown by an arrow 22-22 of Fig. 21. [Fig. 23]
A sectional view taken on line 23-23 of Fig. 22. [Figs. 24 (a) and 24(b)]
View showing a variation in position of a head pipe with respect to the center line of the rear frame, wherein Fig. 24(a) is a side view of a main frame, and Fig. 24 (b) is a view seen in the direction shown by an arrow B of Fig. 24(a). [Figs. 25(a) and 25(b)]
Views, similar to Figs. 24(a) and 24(b), showing a variation in position of a head pipe in a state in which fastening planes of the front frame and the rear frame extend substantially in the horizontal direction, wherein Fig. 25(a) is a side view of the main frame, and Fig. 25 (b) is a view seen in the direction shown by an arrow B
of Fig. 25(a). [0010]
Figs. 1 to 24 show one embodiment of the present invention, wherein Fig. 1 is a side view of a scooter-type vehicle; Fig. 2 is an enlarged side view of a front portion of the scooter-type vehicle; Fig. 3 is an enlarged side view of a rear portion of the scooter-type vehicle; Fig. 4 is a view, seen in the direction shown by

an arrow 4 of Fig. 3, of the rear portion of the scooter-type vehicle from which a luggage box and a fuel tank are omitted; Fig. 5 is a perspective view of a front frame and a rear frame which are separated from each other; Fig. 6 is an enlarged side view of the front frame; Fig. 7 is a view seen in the direction shown by an arrow 7 of Fig. 6; Fig. 8 is an enlarged sectional view taken on line 8-8 of Fig. 6; Fig. 9 is an enlarged sectional view taken on line 9-9 of Fig. 7; Fig. 10 is an enlarged sectional view taken on line 10-10 of Fig. 7; Fig. 11 is an enlarged side view of the rear frame; Fig. 12 is an enlarged sectional view seen in the direction shown by an arrow 12 of Fig. 11; Fig. 13 is an enlarged sectional view taken on line 13-13 of Fig. 12; Fig. 14 is a side view, with parts partially cutaway, showing a portion for swingably supporting an engine on a body frame; Fig. 15 is a sectional view taken on line 15-15 of Fig. 14; Fig. 16 is a side view showing a portion for mounting a rear cushion unit to the body frame; Fig. 17 is a sectional view taken on line 17-17 of Fig. 16; Fig. 18 is a sectional view taken on line 18-18 of Fig. 17; Fig. 19 is a side view of a sub-frame; Fig. 20 is a view seen in the direction shown by an arrow 20 of Fig. 19; Fig. 21 is an enlarged view seen in the direction shown by an arrow 21 of Fig. 1; Fig. 22 is a view seen in the direction shown by an

arrow 21 of Fig. 1; Fig. 23 is a sectional view taken on line 23-23 of Fig. 22; and Figs. 24(a) and 24(b) are views showing a variation in position of a head pipe with respect to the center line of the rear frame, wherein Fig. 24(a) is a side view of a main frame, and Fig. 24 (b) is a view seen in the direction shown by an arrow B of Fig. 24(a) . [0011]
Referring first to Fig. 1, a body frame F of a scooter-type vehicle includes a main frame 21 and a sub-frame 22 fastened to a rear portion of the main frame 21. The main frame 21 is formed by fastening a front end portion of a rear frame 24 as a second frame to a rear end portion of a front frame 23. The front frame 23 and the rear frame 24 are each formed from an aluminum alloy7 by casting. The sub-frame 22 is fastened to a rear end portion of the rear frame 24. In this way, the body frame F is formed by fastening the front frame 23, the rear frame 24, and the sub-frame 22 to each other in this order from the front side. [0012]
Referring particularly to Fig. 2, the front frame 23 has at its front end a head pipe 25, and a front fork 28 disposed astride a front wheel WF is steerably supported by the head pipe 25. Lower ends of the front


fork 28 are disposed in front of an axle 31 of the front wheel WF. One end of a link 29 is connected to the lower end of the front fork 28, and the other end of the link 29 is connected to the axle 31. A front cushion 30 is provided between an intermediate portion in the vertical direction of the front fork 28 and an intermediate portion of the link 29. A steering handlebar 32 is connected to an upper end of the front fork 28. [0013]
Referring particularly to Figs. 3 and 4, a power unit P including an engine E disposed in front of a rear wheel WR and a continuously variable transmission M disposed leftwardly from the rear wheel WR is vertically swingably supported by an intermediate portion in the longitudinal direction of the rear frame 24. The engine is typically configured as a water-cooled single-cylinder/four- cycle engine disposed substantially in the horizontal direction with its cylinder directed forwardly of the vehicle. The continuously variable transmission M is typically configured as a belt-type transmission. [0014]
The rear wheel WR is rotatably supported by a rear portion of the power unit P. A rear cushion unit 33 is provided between the rear portion of the power unit P and a rear portion of the main frame 23, that is, the rear

frame 24. An air cleaner 34 is mounted on the rear portion of the power unit P at a position offset upwardly, sideways from the rear wheel WR. The air cleaner 34 is connected to the engine E via a carburetor 35. An exhaust pipe 36 for introducing exhaust gas from the engine E projects from the engine E and extends on the right side from the rear wheel WR. The exhaust pipe 36 is connected to an exhaust muffler 37 disposed on the right side from the rear wheel WR. A stand 38 is turnably supported by the engine E, and the radiator 44 is disposed on the right side from the power unit P.
[0015]
Referring particularly to Figs. 5 to 7, the front frame 23 integrally includes the head pipe 25, a down frame 26 extending downwardly from the head pipe 25, and a pair of right and left floor supporting frames 272 and 21 x extending rearwardly from a lower end of the down frame 26, and is formed by casting.
[0016]
As shown in Fig. 8, the down frame 26 is formed into a groove-shape opened forwardly, downwardly, and a plurality of ribs 26a disposed in the groove are integrally provided on the down frame 26.
[0017]
The pair of right and left floor supporting frames

272 and 271, which extend in line, are each formed into a groove-shape opened upwardly. Front ends of both the floor supporting frames 272 and 271 are disposed for connecting to both sides of a lower end portion of the down frame 26 via a pair of curved portions 502 and 501 expanded forwardly from the front surface of the lower end portion of the down frame 26. The curved portions 502 and 501 are each formed into a groove-shape opened upwardly. A recess 51, which is recessed outwardly, is provided in each of the inner portions, opposed to each other, of the curved portions 502 and 501 [0018]
Referring to Fig. 9, ribs 52 extending in the longitudinal direction is integrally provided on each of the floor supporting frames 272 and 271. A pair of drain holes 53 for discharging water permeated in each of the floor supporting frames 272 and 271 are formed in a bottom portion of each of the floor supporting frames 272 and 271 in such a manner as to be located on both sides of the ribs 52. A drain hole 54 is also provided in a bottom portion of each of the curved portions 502 and 501 [0019]
Rear end portions of the floor supporting frames 272 and 271 are integrally connected to each other via a reinforcing frame 55 formed into an approximately U-shape

opened upwardly. [0020]
Front fastening plates 562 and 561 tilted forwardly, downwardly are integrally provided on the rear ends of the floor supporting frames 272 and 271. A pair of bolt insertion holes 57 are provided in each of the front fastening plates 562 and 561. Further, as shown in Fig. 10, a single fitting recess 58 having the axial line parallel to the axial lines of the bolt insertion holes 57 is opened in a bottom surface of the front fastening plate 561 at a position between both the bolt insertion holes 57; and a pair of fitting recesses 58 having the axial lines parallel to the axial lines of the bolt insertion holes 57 are provided in a bottom surface of the front fastening plate 562 at positions between both the bolt insertion holes 57 . [0021]
Referring particularly to Figs. 11 and 12, the rear frame 24 integrally includes a frame main portion 24a formed into an approximately U-shape opened forwardly as seen from above, and a reinforcing frame 24b for connecting arms of the frame main portion 24a at an intermediate portion thereof. The rear frame 24 is basically formed by casting into a shape tilted rearwardly.

[0022]
Rear fastening plates 612 and 611 tilted forwardly, downwardly are integrally provided on front ends of the arms of the frame main portion 24a of the rear frame 24. The rear fastening plates 612 and 6l1 are to be overlapped from below to the front fastening plates 562 and 561 provided at the rear ends of the front frame 23. [0023]
A pair of bolt insertion holes 62 corresponding to the bolt insertion holes 57 provided in the front fastening plates 562 and 561 are provided in each of the rear fastening plates 6l2 and 611. As shown in Fig. 13, a single fitting projection 63 having the axial line parallel to the axial lines of the bolt insertion holes 62 is provided on the rear fastening plate 611 in such a manner as to project upwardly from a portion between both the bolt insertion holes 62. The fitting projection 63 is to be fitted in the fitting recess 58 provided in the front fastening plate 561. Further, as shown in Fig. 13, a single fitting projections 63 having the axial lines parallel to the axial lines of the bolt insertion holes 62 are provided on the rear fastening plate 612 in such a manner as to project upwardly from portions between both the bolt insertion holes 62. The fitting projections 63 are to be fitted in the fitting recesses 58 provided in

the front fastening plate 562.
[0024]
The rear fastening plates 6l2 and 611 are overlapped from below to the front fastening plates 562 and 561, and are fastened thereto by screwing nuts 65 to bolts 64 passing through the bolt insertion holes 62 of the rear fastening plates 612 and 6l1 and the bolt insertion holes 57 of the front fastening plates 562 and 561 In the state in which the rear fastening plates 612 and 611 to the front fastening plates 562 and 561 being fitted, the fitting projections 63 are fitted in the fitting recesses 58. In this way, a plurality (three or more) of portions
(three fitting projections 63 in this embodiment) of the fastening portions at the front ends of the rear frame 24 are fitted in a plurality (three or more) of portions
(three fitting recesses 58 in this embodiment) of the fastening portions at the rear ends of the floor supporting frames 272 and 271.
[0025]
As described above, a plurality of the bolts 64 (a pair of the bolts 64 in this embodiment) are provided for fastening each of the rear fastening plates 612 and 611 to the corresponding one of the front fastening portion 562 and 561. With respect to these bolts 64, the extension line L of the axial line of at least one of the bolts 64

a pair of stopper rubbers 70 and 71. One end of each of the links 682 and 681 is swingably connected to the corresponding one of the engine side brackets 672 and 671, and the other end of each of the links 682 and 681 is swingably connected to the frame main portion 24a of the rear frame 24. The stopper rubbers 70 and 71 are provided on the link 681 in such a manner as to be brought into contact with the reinforcing frame 24b of the rear frame 24. [0028]
The engine side brackets 672 and 671 are provided on the engine E in such a manner as to project upwardly therefrom. The brackets 672 and 671 have mounting holes 72 extending coaxially with each other. A rubber bush 73 is press-fitted in each of the mounting holes 72. A cylindrical spacer 74 is interposed between both the rubber bushes 73. A bolt 75 having a head 75a to be engaged with the outer side surface of the link 681 is allowed to pass through the rubber bushes 73 and the spacer 74, and a projecting portion of the bolt 75 from the link 682 is screwed in a nut 84 engaged with the outer side surface of the other link 682. In this way, the bolt 75 horizontally disposed while being connected to the end portions of the links 682 and 681 is supported by the engine side brackets 672 and 671 via the rubber bushes 73.

(each of the extension lines L of the axial lines of a pair of the bolts 64 in this embodiment) is set to pass through a space between an upper end of the steering handlebar 32 steerably supported by the head pipe 25 for enabling steering operation and the axle 31 of the front wheel WF as shown in Fig. 1. As a result, since each of the fitting projections 63 and the fitting recesses 58 is disposed between a pair of the bolts 64 and has the axial line parallel to the axial lines of the bolts 64, the extension line of each of the fitting projections 63 and the fitting recesses 58 is also set to pass through the space between the upper end of the steering handlebar 32 and the axle 31 of the front wheel WF. [0026]
Incidentally, the engine E of the power unit P is / supported by the rear frame 24 of the body frame F via a vibration-proof link 66. Hereinafter, the structure of the vibration-proof link 66 will be described with reference to Figs. 14 and 15. [0027]
The vibration-proof link 66 includes a pair of right and left engine side brackets 672 and 671 provided on the engine E; a pair of right and left links 682 and 681 disposed in front of the carburetor 35; a cross-member 69 for connecting the links 682 and 681 to each other; and

[0029]
Supporting holes 76 are coaxially provided in intermediate portions of the both arms of the frame main portion 24a of the rear frame 24. A rubber bush 77 is press-fitted in each of the supporting holes 76. Bolts 78 provided at the other ends of the links 682 and 68l in such a manner as to be parallel to the bolt 75 are swingably supported by the frame main portion 24a via the rubber bushes 77.
[0030]
A box-shaped rubber supporting portion 79 is provided on the link 681 in such a manner as to be offset forwardly from a straight line connecting the centers of the bolt 75 and the bolt 78 to each other. A contact plane 81 to be in contact with a stopper rubber 70 mounted on the rubber supporting portion 79 is formed on the bottom surface of the reinforcing frame 24b of the rear frame 24. A box-shaped rubber supporting portion 80 is provided on the link 681 in such a manner as to be offset rearwardly from the straight line connecting the centers of the bolt 75 and 78 to each other. A contact plane 82 to be in contact with a stopper rubber 71 mounted on the rubber supporting portion 80 is formed on the bottom surface of the reinforcing frame 24b of the rear frame 24.


[0031]
The cross-member 69 for connecting the links 682 and 6B1 to each other, which is formed into an approximately U-shape opened downwardly, is disposed astride an intake pipe 83 for connecting the carburetor 35 disposed behind the link 681 and the engine E. [0032]
With this vibration-proof link 66, a load applied from the engine E of the power unit P to the bolt 75 is absorbed by elastic deformation of the rubber bushes 73, elastic deformation of the stopper rubbers 70 and 71 pushed to the contact planes 81 and 82, and elastic deformation of the rubber bushes 77. [0033]
An upper end portion of the rear cushion unit 33 with its lower end connected to the power unit P is mounted to the rear portion of the main frame 21 of the body frame F. The structure for mounting the upper end of the rear cushion unit 33 on the main frame 21 will be described with reference to Figs. 16 to 18. [0034]
A cushion side bracket 86 formed into an approximately U-shape opened upwardly is provided on the upper end of the rear cushion unit 33. On the other hand, an opening portion 87 allowing the cushion side bracket

86 to pass therethrough is formed in the rear portion of
the main frame 21, that is, in the rear portion of the
frame main portion 24a of the rear frame 24 at a position
corresponding to the rear cushion unit 33.
[0035]
A cushion mounting portion 88 raised upwardly from the frame main portion 24a, crossing the opening portion
87 is integrally provided on the frame main portion 24a.
The cushion side bracket 86 is disposed in such a manner
as to hold the cushion mounting portion 88 between both
legs of the U-shaped bracket 86.
[0036]
The cushion mounting portion 88 has a mounting hole 89 in which a rubber bush 90 is press-fitted. A bolt 91 passing through the rubber cushion 90 is screwed in the / cushion side bracket 86. In other words, the cushion side bracket 86 is mounted to the cushion mounting portion 88 via the rubber cushion 90. [0037]
Referring to Figs. 19 and 20, the sub-frame 22 is formed by welding metal pipes. The sub-frame 22 includes a frame portion 92 formed into an approximately U-shape opened forwardly as seen from above; a pair of rising portions 93 extending in the vertical direction and welded at their intermediate portions to both edges of a


front end portion of the frame portion 92; and a pair of reinforcing portions 94 each of which has one end welded to a lower end of the rising portion 93 and has the other end welded to the frame portion 92. The sub-frame 22 is formed symmetrically in right and left with respect to the center line extending in the longitudinal direction of the body frame 21. [0038]
Bolt insertion holes 97 are provided in the lower end portions of the rising portions 93. Similarly, bolt insertion holes 98 are provided in intermediate portions of the reinforcing portions 94 overlapped to the lower end portions of the rising portions 93. On the other hand, a pair of bosses 99 corresponding to the bolt insertion holes 97 and a pair of bosses 100 corresponding to the bolt insertion holes 98 are integrally provided on the frame main portion 24a of the rear frame 24 in such a manner as to be raised upwardly therefrom. The sub-frame 22 is thus mounted on the bosses 99 and 100 by means of bolts 101 and nuts 102. In this case, the bosses 99 and 100 arranged on the left side of the frame main portion 24a are disposed at positions near the connection portion between the cushion mounting portion and the frame main portion 24a. Accordingly, the sub-frame 22 is fastened to the frame main portion 24a at the position near the

connection portion between the cushion mounting portion
88 and the frame main portion 24a.
[0039]
The luggage box 3 9 capable of accommodating a helmet, etc. is supported on the rear frame 24 and the sub-frame 22 in such a manner as to be disposed over the engine E and the carburetor 35. [0040]
As is apparent from Fig. 15, a pair of legs 106 and 105 are provided on a lower end on the front side of the luggage box 3 9 in such a manner as to project downwardly therefrom. On the other hand, supporting recesses 108 and 107 for receiving the legs 106 and 105 are provided on an upper surface of the reinforcing frame 24b of the rear frame 24. The legs 106 and 105 received in the supporting-recesses 108 and 107 are fastened to the reinforcing frame 24b of the rear frame 24 by means of bolts 109 and nuts 110. The bottom portions of the reinforcing frame 24b and the luggage box 39 are tilted rightwardly, downwardly when seeing in the running direction of the scooter-type vehicle in order to avoid interference with the intake pipe 83 and the carburetor 35 disposed under the reinforcing frame 24b and the luggage box 39. [0041]
Flat mounting plates 111 are provided on upper ends

of the rising portions 93 of the sub-frame 22, and nuts 112 are welded to the mounting plates 111. A rear end of the luggage box 39 is placed on these mounting plates 111 of the sub-frame 22, and is mounted thereto by screwing bolts 113 (see Fig. 1) to the nuts 112. [0042]
In this way, the luggage box 39 is supported by the rear frame 24 and the sub-frame 22 at the position over the engine E and the carburetor 35. In this case, the cross-member 69 of the vibration-proof link 66 is disposed between the luggage box 3 9 and the engine E. [0043]
The fuel tank 40 is supported on the sub-frame 22 at a position behind the luggage box 39. To support the fuel tank 40, a mounting plate 114 is welded to an upper' surface of the rear end of the frame portion 92 of the sub-frame 22, and mounting plates 115 are welded on the intermediate portions of the arms of the frame 92. A pair of nuts 116 are welded on the mounting plate 114, and the nuts 117 are welded on the mounting plates 115. In this way, the rear portion of the fuel tank 40 disposed in the frame portion 92 is supported on the mounting plate 114 by screwing bolts 118 (see Figs. 1 and 2) to the nuts 116, and both sides of the fuel tank 40 are supported on the mounting plates 115 by screwing bolts 119 (see Figs. 1

and 2) to the nuts 117.
[0044]
The body frame F is covered with a synthetic resin made body cover 41. The body cover 41 includes a leg shield 41a for covering in front of driver's legs; a step floor 41b on which the driver's legs are to be placed; an under-cover 41c for covering the bottom side of the step floor 41b; and a side cover 41d for covering both sides of the rear portion of the vehicular body.
[0045]
Most of the luggage box 39 supported on the rear frame 24 and the sub-frame 22 and the fuel tank 40 supported on the sub-frame 22 are covered with the side cover 41d. A seat 42 capable of covering the luggage box 39 from above is openably/closably mounted on an upper / portion of the side cover 41d. A fuel filler cap 40a of the fuel tank 40 is provided on the upper portion of the side cover 41d in such a manner as to project upwardly therefrom.
[0046]
Referring particularly to Fig. 2, a mounting plate 45 opposed to the back surface of the head pipe 25 with a gap put therebetween is integrally provided on a back surface portion of the head pipe 25. A nut supporting member 46 formed into an approximately U-shape opened

downwardly is fitted from above to the mounting plate 45, and a nut 47 disposed between the back surface of the head pipe 25 and the mounting plate 45 is welded to the nut supporting member 46. A hook 4 8 to hang a shopping bag is brought into contact with a portion, corresponding to the mounting plate 45, of the leg shield 41a of the body cover 41. A screw member 49, which is inserted in the nut supporting member 46 and the mounting plate 45 and engaged with the hook 48, is screwed to the nut 47.
[0047]
Referring to Figs. 21 to 23, a pair of floor
supporting plates 122 and 121 spaced from each other in
the longitudinal direction are disposed to cross between
the floor supporting frames 272 and 27x of the front frame
23.
[0048]
Bolt insertion holes 123 are provided in front portions of the floor supporting frames 272 and 271 and approximately U-shaped nut supporting members 125 to which nuts 124 corresponding to the bolt insertion holes 123 are welded are fitted from sideways to the floor supporting frames 272 and 271 The under-cover supporting members 126, both ends of the floor supporting plate 121 in the longitudinal direction, and both side portions of the front portion of the step floor 41b are placed on the


nut supporting members 125. The step floor 41b, floor supporting plate 121, and under-cover supporting members 126 are fastened altogether to the floor supporting frames 272 and 211 by screwing bolts 127 to the nuts 125. To prevent heads of the bolts 127 from projecting upwardly, the step floor 41b has recesses 128 for receiving the heads of the bolts 127. [0049]
A raised portion 121a raised upwardly is provided at a central portion of the floor supporting plate 121 in the longitudinal direction. The center of the front end of the step floor 41b and the lower end portion of the leg shield 41a are supported by the raised portion 121a. [0050]
Both the longitudinal end portions of the floor supporting plate 122, which supports the step floor 41b from below in co-operation of the floor supporting plate 121, has the same structure as that of the floor supporting plate 121. That is to say, both the end portions of the floor supporting plate 122 are fastened altogether, together with the step floor 41b, to the floor supporting frames 272 and 271 by means of bolts 129. The step floor 41b has recesses 130 for receiving heads of the bolts 129. Bolt insertion holes 140 allowing the bolts 129 to pass therethrough are provided in the rear


portions of the floor supporting frames 272 and 271
[0051]
The under-cover 41c is disposed to cover, from below, both the floor supporting frames 272 and 271 of the front frame 23, and is fastened to the under-cover supporting members 126 by means of bolts 131 and nuts 132.
[0052]
A box-shaped container 133 opened upwardly is disposed between the floor supporting frames 272 and 271 Supporting flanges 133b and 133a projecting towards the floor supporting frames 272 and 211 sides are integrally provided on both sides of an upper end of the container 133. Recesses 135 and 134 provided at outer ends of the supporting flanges 133b and 133a are received by inner upper edges of the floor supporting frames 272 and 271.
[0053]
A supporting flange 133c to be placed on an upper surface of a lower portion of the down frame 26 is integrally provided on a front portion of an upper end of the container 133. The supporting flange 133c is fastened to the lower portion of the down frame 26 by a bolt 135 passing through a bolt insertion hole 134 provided in the lower portion of the down frame 26 and a nut 136 screwed to the bolt 135.
[0054]

A supporting flange 133d to be placed on a central portion of the reinforcing frame 55 in the width direction is integrally provided on a lower portion of a rear end of the container 133. The supporting flange 133d is fastened to the central portion of the reinforcing frame 55 in the width direction by a bolt 138 passing through the supporting flange 133d and a bolt insertion hole 137 provided in the central portion of the reinforcing frame 55 in the width direction and a nut 139 screwed to the bolt 138. [0055]
A battery 143 is housed in a front portion of the container 133. Hooks 144 and 145 engaged with the container 133 are disposed in front of and behind the battery 143. The battery 143 is fixed in the container 133 by engaging both ends of a belt 146 spread over the top of the battery 143 with the hooks 144 and 145. [0056]
A radiator reservoir tank 147 is fixed in the container 133 at a position behind the battery 143. [0057]
An opening portion 148 is provided at a central portion of the step floor 41b at a position corresponding to that of the container 133. The opening portion 148 is openably closed with a lid 149 fastened to the step floor

41b with a screw member 150. An upper surface of the lid 149 when the lid 149 is closed is at the same level as that of an upper surface of the step floor 41b.
[0058]
The function of this embodiment will be described below. The body frame F of the scooter-type vehicle is formed by fastening the front frame 23, rear frame 24, and sub-frame 22 to each other. At least one of the frames 23, 24 and 22 is formed by casting (the front frame 23 and rear frame 24 are formed by casting in this embodiment). Accordingly, by commonly using either the front frame 23 or the rear frame 24 to various kinds of motorcycles different in part of the body frames, it is possible to reduce the design and manufacturing costs of the body frame required for change in kind of the motorcycle. Further, since it is possible to modularize the frames 23, 24 and 22 and perform the assembly of parts for each of the frames 23, 24 and 22, and hence to manufacture a scooter-type motorcycle by assembling the three modules having been sub-assembled to each other, and hence to improve the assembling efficiency in the process of manufacturing the scooter-type motorcycle.
[0059]
The front frame 23 including the head pipe 25, down frame 26, and floor supporting frames 272 and 271 is

integrally formed by casting; the rear frame 24 formed by casting are fastened to the rear ends of the floor supporting frames 272 and 271; and the sub-frame 22 formed by welding the metal pipes is fastened to the rear end of the rear frame 24. Accordingly, the sub-frame 22 relatively low in design and manufacturing costs is allowed to easily keep up with the change in any kind of the motorcycle by changing the metal pipes to be welded. [0060]
The rear frame 24 is fastened to the pair of right and left floor supporting frames 272 and 211 of the front frame 23 by overlapping and fastening the rear fastening plates 6l2 and 611 provided at the branched front ends of the rear frame 24 to the front fastening plates 562 and 561 provided at the rear ends of the floor supporting frames 272 and 271. Each of the front fastening plates 562 and 561 and the rear fastening plates 612 and 61: is, as shown in Fig. 24(a), formed into a shape tilted forwardly, downwardly. Accordingly, on the projection of the head pipe 25 and the fastening planes of the fastening plates 562, 56l 6l2 and 611 to a plane parallel to the fastening planes, as shown in Fig. 24(b), the fastening planes of the fastening plates 562, 561 612 and 611 are disposed at positions relatively close to the head pipe 25. With this configuration, as shown in Fig. 24(b), even if there


occurs an error in assembling the rear fastening plates 612 and 611 on the rear frame 24 side to the front fastening plates 562 and 561 on the front frame 23 side and thereby the position of the head pipe 25 is tilted from the center line C of the rear frame 24 in the width direction. Thus, it is possible to make relatively small displacement amounts l and 2 of the position of the head pipe 25 with respect to the center line C of the rear frame 24 in the width direction, and hence to improve the positioning accuracy of the front wheel WF and the rear wheel WR to the vehicular body.
[0061]
Further, the extension line L of the axial line of at least one the pairs of bolts 64 for fastening the front fastening plates 562 and 561 to the rear fastening plates 612 and 611 (the extension lines L of the axial lines of the pair of bolts 64 in this embodiment) is set to pass through the space between the upper end of the steering handlebar 32 supported by the head pipe 25 and the axle 31 of the front wheel WF, so that the above fastening planes are disposed at positions closer to the head pipe 25. As a result, even if there occurs an error in assembling the rear frame 24 to the front frame 23, it is possible to make small the displacement amounts 1 and
2 of the position of the head pipe 25 with respect to

the center line c of the rear frame 24 in the width direction.
[0062]
On the contrary, if the fastening planes of the rear ends of the front frame 23 and the front ends of the rear frame 24 are not tilted forwardly, downwardly as shown in Fig. 25(a), but extend substantially in the horizontal direction, on the projection of the head pipe 25 and the above fastening planes of the rear ends of the front frame 23 and the front ends of the rear frame 24 to a plane parallel to the fastening planes, as shown in Fig. 25(b), the fastening planes are disposed at positions relatively apart from the head pipe 25. As a result, when there occurs an error in assembling the rear frame 24 to the front frame 23, the displacement amounts l and 2 of the position of the head pipe 25 with respect to the center line C of the rear frame 24 in the width direction becomes relatively large.
[0063]
Since the rear fastening plates 612 and 611 are overlapped from below to the front fastening plates 562 and 561 a space for disposing the rear frame 24 over the rear ends of the floor supporting frames 272 and 271 is not required to be ensured. As a result, it is possible to allow the step floor 41b to extend up to a position

over the rear ends of the floor supporting frames 272 and 271 and hence to make large the space of the step floor 41b. [0064]
Since the fitting recesses 58 are provided in the rear ends of the floor supporting frames 272 and 271 and the fitting projections 63 to be fitted in the fitting recesses 58 are provided on the front ends of the rear frame 24, it is possible to improve the assembling accuracy in fastening and assembling the rear frame 24 to the front frame 23. [0065]
Further, since three or more (three in this embodiment) pieces of the fitting recesses 58 are formed in the rear ends of the floor supporting frames 273 and 271 and three or more (three in this embodiment) pieces of the fitting projections 63 are provided on the front ends of the rear frame 24, it is possible to further improve the accuracy in assembling the rear frame 24- to the front frame 23. [0066]
Since the down frame 26 of the front frame 23 is formed into the groove-shape opened upwardly, downwardly, the front wheel WF is allowed to be closer to the down frame 26 without reducing the cross - sectional shape of

the down frame 26. Accordingly, it is possible to shorten the length of the wheel base while avoiding interference between the front wheel WF and the down frame 26, and sufficiently ensuring the space of the step floor 41b.
[0067]
Since the pair of right and left floor supporting frames 272 and 271 are each formed into the groove-shape opened upwardly, when an external force is applied to the body frame F, the floor supporting frames 272 and 211 are deflected in such a manner that the areas of the upper opening portions thereof are changed. This makes it possible to improve the riding comfort.
[0068]
Since the ribs 52 extending in the longitudinal direction are provided on the floor supporting frames 272 and 271, when an external force is applied to the body frame F, the floor supporting frames 272 and 271 are allowed to be deflected with their rigidities not reduced so much.
[0069]
The front ends of the floor supporting frames 272 and 271 are disposed on both the sides of the lower end of the down frame 26, the step floor 41b can be disposed in such a manner as to extend up to both the sides of the lower end of the down frame 26, and hence to sufficiently


ensure the space of the step floor 41b on the front side without enlarging the wheel base.
[0070]
The front ends of the floor supporting frames 272 and 271 are connected to both the sides of the lower end of the down frame 26 via the pair of curved portions 502 and 501 expanded forwardly from the front surface of the lower end of the down frame 26, the connection portions between the down frame 26 and the floor supporting frames 272 and 211 are expanded forwardly as the curved portions 502 and 501 although the front ends of the pair of floor supporting frames 272 and 271 extending in line are disposed at the connection portions. As a result, it is possible to sufficiently increase the strength of the connection portions.
[0071]
In addition, the front wheel WF can be disposed close to the curved portions 502 and 501 side while ensuring a gap between the front wheel WF and the curved portions 502 and 501 by providing the recesses 51 on the opposed inner sides 6£ the curved portions 502 and 501 so that it is possible to avoid an inconvenience that the wheel base is enlarged by the fact that the front ends of the floor supporting frames 272 and 211 are connected to the down frame 26 via the curved portions 502 and 501

[0072]
With respect to the vibration-proof link 66 for swingably supporting the engine E of the power unit P on the body frame F, the pair of right and left links 682 and 681 are provided for swingably connecting the pair of right and left engine side brackets 672 and 671 provided on the engine E to the body frame F, and the cross-member 69 is provided for connecting the right and left links 682 and 681 to each other. The cross-member 69 is formed into the approximately U-shape opened downwardly, and is disposed at a position astride the intake pipe 83 for connecting the carburetor 35 disposed behind the links 682 and 681 to the engine E on the front side of the links 682 and 681. Accordingly, as compared with a structure in which the carburetor 35 is disposed in front of the links 682 and 681 the degree of freedom in arrangement of the carburetor 35 becomes larger. [0073]
Further, since the engine E is a four-cycle engine disposed substantially in the horizontal direction and the cross-member 69 is disposed between the luggage box 39 mounted on the body frame F under the seat 42 and the engine E, it is possible to prevent the position of the seat 42 from becoming higher in the case of ensuring the free motion of the cross-member 69 while avoiding the


interference with the luggage box 39.
[0074]
Since the opening portion 87 allowing the cushion side bracket 86 provided at the upper end of the rear cushion unit 33 to pass therethrough is provided in the frame main portion 24a of the rear portion of the main frame 21 of the body frame F; the cushion mounting portion 88 raised upwardly from the frame main portion 24a while crossing the opening portion 87 is mounted on the frame main portion 24a; and the cushion side bracket 86 is mounted on the cushion mounting portion 88, it is possible to set the cushion side bracket 86 at a high position, and hence to make larger the stroke of the rear cushion unit 33. This makes it possible to improve the riding comfort.
[0075]
Since the sub-frame 22 constituting the body frame F in co-operation of the main frame 21 is fastened to the main frame 21 at a position near the connection portion between the cushion mounting portion 88 and the frame main portion 24a, it is possible to reinforce the strength of the cushion mounting portion 88 raised from the frame main portion 24a by the sub-frame 22.
[0076]
While the embodiment of the present invention has

been described, the present invention is not limited to the embodiment, and it is to be understood that many changes in design may be made without departing the scope of the claims. [00771
For example, the front frame 23 and the rear frame 24 are formed by casting in the above embodiment; however, the present invention can be applied to the case in which the front frame 23 and the rear frame 24 are formed from a synthetic resin by molding. [0078]
[Effect of the Invention]
As described above, according to the invention described in claim 1, since at least one of the first, second and third frames is produced by die-forming, such a frame can be shared among various kinds of motorcycles made different from each other by changing part of each body frame, with a result that it is possible to reduce the design and production costs of a body frame due to the model change of body frame. Further, since each of the first, second and third frames can be modularized, a motorcycle can be assembled by mounting parts to each modularized frame and then assembling these three modules having been sub.assembled to each other. As a result, it is possible to improve the assembling efficiency of the

motorcycle. [0079]
According to the invention described in claim 2, it is possible to reduce the design and production costs due to the model change of body frame of the scooter-type motorcycle and to improve the assembling efficiency of the motorcycle. Also, since each of the first and second frames as main portions of the body frame of the scooter-type motorcycle is formed by casting, it is possible to further reduce the design and product costs by sharing/converting either the first frame or the second frame among various kinds of scooter-type motorcycles. The third frame at the rear portion of the body frame, which is relatively low in design and production costs, can be easily formed by working metal pipes in accordance' with the model change of body frame of the motorcycle.
[Explanation of Characters]
22: sub-frame as third frame, 23: front frame as first frame, 24: rear frame as third frame, 25: head pipe, 26: down frame, 21 x, 272: floor supporting frame, 33: rear cushion unit, 41b: step floor, F: body frame, WF: front
wheel, p: power unit



WE CLAIM:
1. A body frame for a motorcycle, including a first frame (23), a
second frame (24) and a third frame (22),
a second frame (24) is fastened to a first frame (23) by means of bolts and nuts, a third frame (22) is fastened to a second frame (24) by means of bolts and nuts,
said first frame (22) is formed by casting and integrally has a head pipe (25) for steerably supporting a front wheel (WR), down frame (26) extending rearwardly, downwardly from said head pipe (25), and floor supporting frames (271 272) extending rearwardly from the lower end of said down frame (26) and disposed under a step floor (41b);
said second frame (24), which swingably supports a power unit (P) and is connected to the upper end of a rear cushion (33), is formed by casting and is fastened to the rear ends of said floor supporting frames (271, 272).
2. A body frame for a motorcycle as claimed in claim 1, wherein
said third frame (22) formed by working metal pipes is fastened to the rear end of said second frame (24).
3. A body frame for a motorcycle substantially as hereinbefore
described with reference to the accompanying drawings.
Dated this 17th day of April, 2000
RITUSHKA NEGI
OF REMFRY & SAGAR
ATTORNEY FOR THE APPLICANTS


Documents:

354-mum-2000-cancelled pages(05-01-2007).pdf

354-mum-2000-claims(granted)-(05-01-2007).doc

354-mum-2000-claims(granted)-(05-01-2007).pdf

354-mum-2000-correspondence(23-3-2006).pdf

354-mum-2000-correspondence(ipo)-(11-10-2004).pdf

354-mum-2000-drawing(28-3-2001).pdf

354-mum-2000-form 1(17-4-2000).pdf

354-mum-2000-form 19(16-11-2004).pdf

354-mum-2000-form 2(granted)-(05-01-2007).doc

354-mum-2000-form 2(granted)-(05-01-2007).pdf

354-mum-2000-form 3(12-3-2001).pdf

354-mum-2000-form 3(17-4-2000).pdf

354-mum-2000-form 5(17-4-2000).pdf

354-mum-2000-petition under rule 138(4-10-2005).pdf

354-mum-2000-power of authority(4-10-2005).pdf

354-mum-2000-power of authority(5-9-2000).pdf

abstract1.jpg


Patent Number 204352
Indian Patent Application Number 354/MUM/2000
PG Journal Number 23/2007
Publication Date 08-Jun-2007
Grant Date 15-Feb-2007
Date of Filing 17-Apr-2000
Name of Patentee HONDA GIKEN KOGYO KABUSHIKI KAISHA
Applicant Address 1-1, MINAMIAOYAMA 2-CHOME, MINATO-KU, TOKYO, JAPAN.
Inventors:
# Inventor's Name Inventor's Address
1 SUSUMU MICHISAKA C/O KABUSHIKI KAISHA HONDA GIJUSTU KENKYUSHO, 4-1, CHUO 1-CHOME, WAKO-SHI, SAITAMA, JAPAN
2 KENICHI SUEDA C/O KABUSHIKI KAISHA HONDA GIJUSTU KENKYUSHO, 4-1, CHUO 1-CHOME, WAKO-SHI, SAITAMA, JAPAN.
PCT International Classification Number B 62 K, 11/10
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 HEI - 11 - 121313 1999-04-28 Japan