BICYCLE FRAME

• Main Authors: SHIMIZU MASAZUMI, TODOROKI HIROSHI
• Format: Patent
• Language: English
• Published: 19.01.1993
• Subjects: CYCLE AXLE SUSPENSIONS; CYCLE FRAMES; CYCLE SIDE-CARS, FORECARS, OR THE LIKE; CYCLE STEERING DEVICES; CYCLES; LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS; PERFORMING OPERATIONS; RIDER-OPERATED TERMINAL CONTROLS SPECIALLY ADAPTED FORCYCLES; TRANSPORTING

PURPOSE:To enhance the productivity and strength by bulging the center of a head pipe rearward, and by forming rub parts having inner parts which can fit with the outer surfaces of the bulged parts extending from straight pipe parts at the upper and lower vertical end parts of the head pipe to the center thereof, in the front parts of upper and lower pipes by a bulging process. CONSTITUTION:A bicycle is composed of a head pipe 1, upper and lower pipes 2, 3 and a vertical pipe 4. In this arrangement, the head pipe 1 is formed at its center with a bulged part 1a bulged toward the rear of the vehicle body. Further, a rug part 2g having an inner surface which can fit to the outer surface extending from a straight pipe part 1b at the upper end of the head pipe to the center bulge part 1a is formed by a bulging process, and this upper pipe 2 is fitted in the top end part of the head pipe 1. Further, similarly, a lug part 3d having an inner surface which can fit the outer surface of a straight pipe part 1c at the lower end of the head pipe is formed by a bulging process, and the pipe 3 is fitted in the lower end part of the head pipe 1.