The present invention is directed to a bearing structure for a camshaft to
prevent obliquely wiping off the oil from the surface of the camshaft
caused by a knife edge. A lower journal (3) for supporting the camshaft
(2) is formed with a counterbore (6) cutting off a part of a bearing
surface (5) of the lower journal (3). A connecting part between the
bearing surface (5) and the counterbore (6) is formed with a recess (11)
hollowed from the bearing surface (5). A part of an edge (11a) connecting
the recess (11) to the bearing surface (5) is elongated along a
perpendicular direction to an axis of the bearing surface (O5), and a
remaining part of the edge (11b) is elongated along a parallel direction
to the axis (O5). The part of the edge (11a) does not wipe off the oil in
the axis direction (O5), while the oil wiped by the remaining part of the
edge (11b) is received into the recess (11) and is used for lubrication.