Patent ID: 7793958

Claim:
Device for attaching the front wheel assembly to the chassis of a motorcycle, the chassis of the motorcycle include a steering head ( 5 ) with upper and lower housings ( 6 a , 6 b ), said device comprising: an upper plate ( 33 , 73 ); a lower plate ( 34 ); a column shaft ( 437 ) connecting the lower plate ( 34 ) and the upper plate ( 33 , 73 ) by the column shaft passing through the steering head ( 5 ), the column shaft ( 437 ) having a cylindrical surface ( 71 ); a guide part ( 414 ) and a ball-joint ( 12 ) located in upper and lower housings of the guide elements of the steering head ( 5 ), the guide part ( 414 ) and the ball-joint ( 12 ) being traversed by the column shaft ( 437 ); a groove located within one said guide part ( 414 ), the groove having parallel sides ( 18 a , 18 b ) with an axis contained in the median plane of the motorcycle; two flat surfaces with parallel sides ( 19 a , 19 b ) along the column shaft ( 437 ) sliding without play on the parallel sides ( 18 a , 18 b ) of the groove; rotating elements ( 11 , 16 , 716 ) placed respectively in the lower plate ( 34 ) and in the upper plate ( 33 , 73 ), the rotating elements allowing rotation of the upper and lower plates on the column shaft ( 437 ) with the column shaft ( 437 ) immobilized therein in rotation relative to the steering head ( 5 ) by the guide part ( 414 ); a shaft ( 30 ) perpendicular to the parallel sides of the groove ( 18 a , 18 b ) and passing via a center of rotation of the ball joint ( 12 ), the front wheel assembly pivotable around the shaft ( 30 ); a nut ( 23 ) positioned at one end of the column shaft ( 437 ), the nut ( 23 ) operative to lock a position of the shaft ( 437 ) at a desired angular value; a centrally concave spherical surface ( 420 ) on the guide part ( 414 ) positioned above a corresponding surface ( 420 ) on the shaft of the steering head ( 5 ); a first eccentric ( 45 ) with a convex spherical surface ( 421 ), the first eccentric ( 45 ) in contact with the guide part ( 414 ) by the convex spherical surface ( 421 ) of the first eccentric being in contact with and having same radius as the convex spherical surface ( 420 ) of the guide part ( 414 ); a bore ( 50 ) within the first eccentric ( 45 ), the bore ( 50 ) having an eccentric vertical shaft a planar surface ( 60 ) on a top on the first eccentric ( 45 ), the planar surface ( 60 ) perpendicular to the shaft of the bore ( 50 ); a second eccentric ( 415 ) having a cylindrical portion ( 51 ) of a size that allows a rotation without play in the bore ( 50 ) of the first eccentric ( 45 ), the second eccentric ( 415 ) having a planar surface ( 61 ) perpendicular to a shaft of the cylinder portion ( 51 ) and resting on the planar surface ( 60 ) of the first eccentric ( 45 ), the second eccentric ( 415 ) having a bore ( 70 ) with an eccentric shaft relative to the shaft of the cylinder portion ( 51 ), and the second eccentric having a bore ( 70 ) allowing rotation of the second eccentric without play around the cylindrical surface ( 71 ) of the column shaft ( 437 ).