Lockable quick-release mechanism

A lockable quick-release mechanism for retaining a device on a bicycle frame comprising:

• a casing having a substantially hollow axial opening;
• a piston head disposed within said axial opening at a proximal end of said casing and being movable from an outermost open condition to an innermost closed condition in relation to said casing;
• a lever extending horizontally through said piston head, being rotatable therein and having an eccentric cam for shifting the position of said casing relative to the bicycle frame;
• flat abutment surfaces formed integrally with said lever adjacent to said eccentric cam;
• a locking disc disposed within said casing distally of said piston head, having a substantially planar portion including a central aperture formed in said planar portion and extension arms projecting from said planar portion in the proximal direction toward said flat abutment surfaces, said extension arms engaging said flat abutment surfaces in the closed condition for preventing rotation of said lever;
• a spindle coaxially disposed within said axial opening of said casing and extending through said aperture for rotating said locking disc from a locked to an unlocked condition;
• and
• a lock means for selectively securing said locking disc in engagement with said abutment surfaces to lock the device to the bicycle frame.