Patent ID: 6779804
Filing Date: 2004-08-24
Classification: B60B,B62B,Y10T

Abstract:
A wheel mounting structure comprising:a substantially U-shaped front frame tube, said U-shaped front frame tube having a curved middle part disposed at a front side, a substantially U-shaped handlebar coupled to two distal ends of said U-shaped front frame tube, two rear frame tubes respectively pivoted to two distal ends of said handlebar and spaced from said front frame tube at a distance, a pivot, a front fork carrying a 12 inch front wheel, said front fork having a top side pivoted to the curved middle part of said front frame tube by said pivot, a rear wheel axle coupled between said rear frame tubes and carrying a pair of 15.5 inch rear wheels, and two side frame tubes bilaterally coupled between said U-shaped front frame tube and said rear frame tubes, wherein: said U-shaped front frame tube has a fixed mounting block at the curved middle part thereof, said fixed mounting block having a positioning hole; said front fork has a control block coupled to the top side thereof and pivoted with the top side to said fixed mounting block of said U-shaped front frame tube by said pivot, said control block comprising a horizontal top wall, a horizontal bottom wall, a vertical sidewall connected between one end of said horizontal top wall and one end of said horizontal bottom wall, a top through hole cut through said horizontal top wall, a bottom through hole cut through said horizontal bottom wall in vertical alignment with said top through hole, a sliding slot in said vertical sidewall, an inner locating notch and an outer locating notch respectively formed in said sliding slot at two sides, a stop block suspended in between said inner locating notch and said outer locating notch, a locating pin pivotally mounted in said top through hole and said bottom through hole, an operation rod perpendicularly fixedly fastened to said locating pin, and a spring sleeved onto said locating pin and stopped between said operation rod and said horizontal bottom wall to impart an upward pressure to said operation rod and said locating pin, said operation rod having an outer end extended out of the sliding slot of said vertical sidewall for operation by hand to shift said operation rod between a first position where said operation rod is engaged into said outer locating notch to hold said locating pin outside the positioning hole of said fixed mounting block of said U-shaped front frame tube for enabling said control block to be turned with said front fork about said pivot relative to said U-shaped front frame tube, and a second position where said operation rod is engaged into said inner locating notch, to hold said locating pin inside the positioning hole of said fixed mounting block of said U-shaped front frame tube, prohibiting said control block and said front fork from a swivel motion relative to said U-shaped front tube.