Vehicle body frame of motorcycles

• US 20050263334A1
• Filed: 08/01/2003
• Published: 12/01/2005
• Est. Priority Date: 08/30/2002
• Status: Active Grant

• Current Assignee: Kawasaki Jukogyo Kabushiki Kaisha (Kawasaki Heavy Industries Limited)
• Original Assignee: Kawasaki Jukogyo Kabushiki Kaisha (Kawasaki Heavy Industries Limited)
• Inventors: Iwata, Ryo, Moritomo, Takeshi, Taniguchi, Nobumasa, Okabe, Yasuhisa
• Granted Patent: US 7,258,186 B2
• Time in Patent Office: Days
• US Class Current: 180/219
• CPC Class Codes: B62K 11/06 the frame being of single-beam type
• CPC Class Codes: B62K 11/08 the beam being fabricated from sheet metal, e.g. forming fuel tank walls
• CPC Class Codes: B62K 19/12 having cast members
• CPC Class Codes: B62K 19/20 welded, soldered, or brazed

Abstract

There is provided a vehicle frame structure for a motorcycle having an appealing appearance, which structure can be assembled lightweight and compact in size and at a reduced cost. The vehicle frame structure includes a head block (2) including a head tube (3), a main frame (11) forked leftwards and rightwards from the head block (2) to form a pair of main frame half portions (11a, 11b) extending rearwardly thereof, and swing arm brackets (8) extending downwardly from rear ends of the main frame half portions (11a, 11b). An inner frame portion (21) of the main frame (11) and the swing arm brackets (8) in their entirety or respective inner portions of the swing arm brackets (8) are integrally formed by an inner member (19) prepared from a metal casting, and at least an outer frame portion of the main frame (11) is formed by an outer member (20) prepared from a sheet metal.

Claims

1. A vehicle frame structure for a motorcycle, which comprises a head block including a head tube, a main frame forked leftwards and rightwards from the head block to form a pair of left and right main frame half portions extending rearwardly thereof, and swing arm brackets extending downwardly from rear ends of the main frame half portions;

wherein an inner frame portion of the main frame positioned inside the vehicle frame structure and the swing arm brackets in their entirety or respective inner portions of the swing arm brackets are integrally formed by an inner member prepared from a metal casting, and

wherein at least an outer frame portion of the main frame is formed by an outer member prepared from a sheet metal;

2. The vehicle frame structure for the motorcycle as claimed in claim 1, wherein a guide passage for introduction of an air to an air cleaner of an engine is formed inside the main frame.

3. The vehicle frame structure for the motorcycle as claimed in claim 2, wherein the air cleaner is positioned within a space delimited between the pair of the left and right main frame half portions of the main frame.

4. The vehicle frame structure for the motorcycle as claimed in claim 2, wherein the inner and outer frame portions of the main frame are configured to represent a generally U-shape, with their openings jointed with each other to define the guide passage therein.

5. The vehicle frame structure for the motorcycle as claimed in claim 2, wherein a flashing plate for deflecting the flow of the air to separate water contained in the air is disposed within the guide passage.

6. The vehicle frame structure for the motorcycle as claimed in claim 2, wherein the head block is formed with an intake passage through which the air is sucked and supplied to the guide passage.

7. The vehicle frame structure for the motorcycle as claimed in claim 6, wherein the head block is a metal casting including an air intake duct that defines the intake passage and the head tube, and is welded to the main frame.

8. The vehicle frame structure for the motorcycle as claimed in claim 1, wherein the inner member is integrally cast with a cross member for connecting the pair of the left and right main frame half portions with each other.

9. The vehicle frame structure for the motorcycle as claimed in claim 1, wherein the inner member is integrally cast with damping ribs.

10. A combination vehicle frame structure for a motorcycle and air cleaner for providing air to an engine, comprising:

a hollow frame body member extending to the front of the motorcycle with an opening for receiving an air flow pressurized by forward movement of the motorcycle and a guide passage connected to the opening for directing air;

an air cleaner positioned downstream of the opening and configured to fit within the hollow frame body member for communication with the guide passage for cleaning the air and with the engine for delivering clean air; and

a flashing plate positioned within the guide passage traverse to the air flow for deflecting the flow of the air to separate water contained in the air.

11. The combination vehicle frame structure of claim 10 wherein the hollow frame body member includes a left and right main frame half portion and the air cleaner is positioned within a space delimited between the pair of the left and right main frame half portions each of which support a guide passage and a traverse flashing plate adjacent openings to the air cleaner.

12. The combination vehicle frame structure of claim 11 further including means for releasing any separate water from the hollow frame body member.