Modular composite bicycle frame

• US 5,456,481 A
• Filed: 03/11/1994
• Issued: 10/10/1995
• Est. Priority Date: 04/07/1989
• Status: Expired due to Fees

• Current Assignee: Softride, Inc.
• Original Assignee: Softride, Inc.
• Inventors: Allsop, Michael G., Allsop, James D.
• Primary Examiner(s): HILL, MITCHELL
• Application Number:
  US08/209,871
• Time in Patent Office: 578 Days
• Field of Search: 280/281.1, 280/274
• US Class Current: 280/281.1
• CPC Class Codes: B29C 45/006 Joining parts moulded in separate cavities
• CPC Class Codes: B29C 45/14836 Preventing damage of inserts during injection, e.g. collapse of hollow inserts, breakage B29C45/14434 takes precedence
• CPC Class Codes: B29C 45/4457 using fusible, soluble or destructible cores
• CPC Class Codes: B29L 2031/3091 Bicycles
• CPC Class Codes: B62J 1/04 Saddles capable of swinging about a horizontal pivot
• CPC Class Codes: B62J 1/08 Frames for saddles; Connections between saddle frames and seat pillars; Seat pillars attaching seat pillars to cycle frames B62K19/36
• CPC Class Codes: B62K 19/16 the material being wholly or mainly of plastics
• CPC Class Codes: B62K 19/22 Adhesive joints
• CPC Class Codes: B62K 19/32 Steering heads bearings therefor B62K21/06
• CPC Class Codes: B62K 25/005 characterised by the axle being supported at one end only
• CPC Class Codes: B62K 3/10 of single-beam type, i.e. connecting steering head to rear axle

Abstract

A bicycle (10) with a frame (12) formed of composite material is disclosed. The frame of this bicycle includes a head section or module (34) that is attached to two body units (36, 38). The body units are formed by injection molding and include outer shells and inner ribs 200. Alternatively, the body units may be formed of a urethane core with a stiffened fiberglass, carbon fibers, or like nonmetallic skin. The head section and body units are formed with bores (78, 81, 83, 90) in which sleeves and cables are seated to accommodate the installation of the other components of the bicycle to the frame. The body is further formed with a set of rearwardly extending members that form the chain stays (22) of the bicycle. Dropouts (104) are seated in recesses formed in the chain stays. The bicycle includes a front derailleur/rear brake assembly (30) with a front derailleur (134) that can be both selectively moved up and down and selectively pivoted along a lateral axis of the bicycle. A one-piece, injection-molded frame and methods of construction are also disclosed.

Claims

1. A bicycle frame assembly for securing a seat assembly, wheels, a crank assembly, a front fork assembly, and a handlebar, the bicycle frame assembly comprising:

(a) a separately-formed first body unit comprising a first outer shell with an inside surface and first internal ribs extending in a plurality of directions, said first internal ribs projecting inwardly from said inside surface of said first outer shell to form a first support structure, said first body unit including a first center section; and

(b) a separately-formed second body unit comprising a second outer shell with an inside surface and second internal ribs extending in a plurality of directions, said second internal ribs projecting inwardly from said inside surface of said second outer shell to form a second support structure, said first and second body units being arranged and configured to mate together, said first outer shell being configured to mate along at least a portion of its perimeter with the perimeter of said second outer shell and at least a portion of said first internal ribs configured to mate with at least a portion of said second internal fibs;

wherein the mated shells enclose said first and second internal ribs within the mated portions of said shells;

wherein said second body unit includes a second center section and a chain stay extending rearwardly of said second center section.

2. The bicycle frame assembly of claim 1, wherein each of said body units is constructed of integrally formed, fiber-reinforced plastic material.

3. The bicycle frame assembly of claim 2, wherein each of said body units further includes head sections formed integral therewith, said head sections including internal ribs that are arranged and configured to abut each other throughout at least a portion of said head section, said head sections including recessed portions adapted to secure a head tube for attachment of the front fork assembly.

4. The bicycle frame assembly of claim 3, wherein said head sections further include mounting means for attachment of a seat assembly, including a seat support beam adapted to extend rearward from said head section, and wherein said center sections extend downwardly and rearwardly from said head sections.

5. The bicycle frame assembly of claim 4, wherein each of said first and second body units includes a chain stay extending from said center section near said bottom bracket bore.

6. The bicycle frame assembly of claim 5, wherein said chain stays extend from said center section above said bottom bracket bore to rearward ends, said chain stays having a broad connection zone to said center section and tapering toward the rearward ends.

7. The bicycle frame assembly of claim 2, further including a head section having means for attachment to said center section of said body units, said head section including a cylindrical portion adapted to secure a head tube and a mounting means for attachment of a seat assembly including a seat support beam adapted to extend rearward from said head section.

8. The bicycle frame assembly of claim 1, wherein said first body unit includes a chain stay, and said second body unit terminates at the bottom of said center section near said bottom bracket such that said second body unit does not include a chain stay.

9. The bicycle frame assembly of claim 1, wherein said first body unit includes an integral head section, said head section being arranged and configured to abut an upper end of the second body unit for attachment therewith, said head section being adapted to secure a head tube and a seat assembly including a seat support beam.

10. A bicycle comprising:

(a) a frame formed of composite material, said frame including at least two separately-formed body units, said body units each having a center section, a head section, and a chain stay extending rearward from said center section;

(b) a seat assembly including a seat support beam attached to said head section, said seat support beam extending rearwardly from said head section, and a seat attached to a portion of said seat support beam distal from said head section;

(c) a from wheel assembly including a front fork assembly rotatably coupled to said head section, a front wheel attached to said front fork assembly below said head section, and a handlebar assembly attached to said front fork assembly above said head section;

(d) a rear wheel rotatably coupled to said chain stays; and

(e) a drivetrain assembly including a free gear secured to said rear wheel, a crank assembly secured to said center section of said body units, and a drive chain connecting said crank assembly to said free gear.

11. The bicycle of claim 10, wherein said body units are symmetrically shaped.

12. The bicycle of claim 10, wherein said frame further includes at least one support rib, and wherein said body units of said frame are each formed with a foam core and skin formed from rigid, nonmetallic material, said body units being adapted to be mated so that said skins of said body units join each other and said skins together being said at least one support rib.

13. The bicycle of claim 10, wherein said body units are each formed of injection-molded plastic with reinforcing fibers, each of said body units including a shell and support fibs, said ribs being integrally formed with and extending from the inside surfaces of said shells, said body units being mated so that said shells join each other to substantially enclose said ribs along at least a portion of said central section.

14. The bicycle of claim 10, wherein said body units include interfitting portions joined together.

15. The bicycle of claim 10, further including a head tube extending longitudinally through said head section and wherein said front fork assembly is disposed in said head tube.

16. The bicycle assembly of claim 15, further including a bottom bracket assembly including a sleeve extending longitudinally through said body units, wherein said crank assembly is rotatably mounted to said bottom bracket assembly.

17. The bicycle assembly of claim 16, further including two dropouts for securing said rear wheel to said chain stays, said dropouts being releasably secured in recesses formed in said chain stays.

18. The bicycle assembly of claim 16, further including a front derailleur and rear brake assembly attached to said body units adjacent said crank assembly, said from derailleur and rear brake including a front derailleur having a chain guide disposed around said drive chain and a brake disposed around said rear wheel.

19. The bicycle assembly of claim 18, wherein said front derailleur and rear brake assembly includes a mount secured to said body units and said front derailleur is connected to said assembly mount to pivot about said assembly mount.

20. The bicycle assembly of claim 10, further including at least one derailleur attached to said frame to change the position of said drive chain, a shifter attached to said head section, and a shifter cable extending from said shifter to said derailleur for controlling the position of said derailleur in response to movement of said shifter and wherein one of said body units is formed with a bore and said derailleur cable is partially disposed in said bore.

21. A bicycle frame comprising:

(a) a head section having means for mounting a seat support beam and means for securing a front fork assembly;

(b) a center section extending downwardly from said head section, the lower end of said center section having means for coupling a crank assembly; and

(c) at least one chain stay extending rearwardly from said center section, said chain stay including means for attaching a rear wheel;

wherein said head section and said center section include a generally centrally located body beam providing the main support and the basic shape of said head section and said center section and support ribs projecting outwardly from said body beam, said support ribs extending across said body beam in a plurality of directions.

22. The bicycle frame of claim 21, wherein said chain stay includes an inner wall extending rearwardly from said body beam and chain stay support ribs projecting outwardly from said inner wall.

23. The bicycle frame of claim 21, further including a shell completely surrounding at least a portion of said support ribs.

24. The bicycle frame of claim 21, wherein said body beam, said inner walls, said support ribs, and said chain stay support ribs are integral members comprising an injection-molded plastic.

25. The bicycle frame of claim 24, further including a shell surrounding at least a portion of said support ribs.

26. The bicycle frame of claim 25, wherein said shell comprises a shrink-wrap plastic material.

27. The bicycle frame of claim 25, wherein said shell comprises a fabric material.

28. A bicycle frame assembly comprising:

(a) a first body unit comprising a first outer shell with an inside surface and first internal ribs, said first internal ribs projecting from said inside surface of said first outer shell to form a first support structure, said first body unit including a chain stay; and

(b) a second body unit comprising a second outer shell with an inside surface and second internal ribs, said second internal ribs projecting from said inside surface of said second outer shell to form a second support structure, said first and second body units being arranged and configured to mate together, said first outer shell being configured to mate along at least a portion of its perimeter with the perimeter of said second outer shell and at least a portion of said first internal ribs configured to mate with at least a portion of said second internal ribs;

wherein at least one of said first and second body units includes a center section, said center section having a bottom bracket bore disposed within a lower portion of said center section, said chain stay extending rearwardly of said center section, said second body unit terminating at the bottom of said center section near said bottom bracket such that said second body unit does not include a chain stay.

29. A bicycle comprising:

(a) a frame formed of composite material, said frame including at least two body units, said body units each having a center section, a head section including a head tube extending longitudinally through said head section and a chain stay extending rearward from said center section;

(b) a seat assembly including a seat support beam attached to hid head section, said seat support beam extending rearwardly from said head section, and a seat attached to a portion of said seat support beam distal from said head section;

(c) a front wheel assembly including a front fork assembly rotatably coupled to said head tube of said head section, a front wheel attached to said front fork assembly below said head section, and a handlebar assembly attached to said front fork assembly above said head section;

(d) s rut wheel rotatably coupled to said chain stays;

(e) a drivetrain assembly including a free gear secured to said rear wheel, a bottom bracket assembly including a sleeve extending longitudinally through said center section of said body units, crank assembly rotatably mounted to said bottom bracket assembly of said body units, and a drive chain connecting said crank assembly to said free gear; and

(f) a front derailleur and rear brake assembly attached to said body units adjacent said crank assembly, said front derailleur and rear brake including a front derailleur having a chain guide disposed around said drive chain and a brake disposed around said rear wheel, wherein said from derailleur and rear brake assembly includes a mount secured to said body units and said front derailleur is connected to said assembly mount to pivot about said assembly mount.