Bicycle handlebar lock

A mechanism for discouraging theft of a bicycle having a wheel on a fork rotatable about an axis relative to a frame headstock for steering the bicycle, and a handlebar mount for manually positioning the fork, the mechanism comprising:

• a first member having means for rigid attachment relative to the fork;
• a second member having means for rigid attachment relative to the handlebar mount, the first and second members being rotatably coupleable and decoupleable at a locking junction, one of the first and second members having at least one aperture carrying a locking body and the other of the first and second members having a receptacle for receiving the locking body, the receptacle having a radially sloping edge contour, the aperture and the receptacle being correspondingly positioned and dimensioned such that the locking body resides within said aperture when the aperture and the receptacle are misaligned, and the locking body can be displaced partway into the receptacle to reside partly in the aperture and partly in the receptacle when the aperture and the receptacle are aligned;
• a lock disposed at the locking junction of the first and second members, the lock having a cam movable between a first position wherein the cam urges the locking body from the aperture toward the receptacle, for fixing the first and second members against relative rotation, such that the bicycle can be operated, and a second position wherein the locking body is free to become retracted into the aperture by action of the sloping edge contour of the receptacle, such that the bicycle cannot be operated;
• wherein the first and second members define a concentrically arranged tube and cylinder, the tube and the cylinder having complementary conical tapers for securing the first and second members in an axial direction;
• and,
• means for fixing the first and second members against relative axial displacement, said means for fixing the first and second members exerting a predetermined axial pressure and includes a split conical bushing having a tapered surface engageable with a further conical taper on one of said first and second members, the split conical bushing being supported axially by an abutment on the other of the first and second members.

A mechanism for discouraging theft of a bicycle having a wheel on a fork rotatable about an axis relative to a frame headstock for steering the bicycle, and a handlebar mount for manually positioning the fork, the mechanism comprising:

• a first member having means for rigid attachment relative to the fork;
• a second member having means for rigid attachment relative to the handlebar mount, the first and second members defining a cylinder and coaxial sleeve and being rotatably coupleable and decoupleable at a locking junction, one of the first and second members having at least one aperture carrying a locking body and the other of the first and second members having a receptacle for receiving the locking body, the receptacle having a radially sloping edge contour, the aperture and the receptacle being correspondingly positioned and dimensioned such that the locking body resides within said aperture when the aperture and receptacle are misaligned, and the locking body can be displaced partway into the receptacle to reside partly in the aperture and partly in the receptacle when the aperture and the receptacle are aligned;
• a lock disposed at the locking junction of the first and second members, the lock having a cam movable between a first position wherein the cam urges the locking body from the aperture toward the receptacle, for fixing the first and second members against relative rotation, such that the bicycle can be operated, and a second position wherein the locking body is free to become retracted into the aperture by action of the sloping edge contour of the receptacle, such that the bicycle cannot be operated, said lock including a cylinder having a shaft rotatable upon release of the lock, the shaft being coupled to the cam, and wherein the lock is operable via a key having a substantially tubular configuration with a uniquely configured axial end for operating lock pins against axial spring pressure, the key having at least one radially protruding guide tab, and being fittable into an annular key receptacle in a body of the lock, the key receptacle having at least one first longitudinal slot for the guide tab, and at least one longitudinal fixing slot for the guide tab, the fixing slot being aligned with the tab when the key is rotated to urge the locking body into the receptacle via said cam, the fixing slot being blocked axially against extraction of the key, whereby the key remains captured in the lock when the first and second members are fixed against relative rotation.