A blade-type tensioner for applying tension to a chain comprising a base, an
arcuately
shaped blade shoe having a chain sliding face, a spring provided on a back side
of the blade shoe, and a guide member. The blade shoe has a proximal end portion
and a distal end portion, where the proximal end portion is swingably supported
on the base, and the distal end portion is slidably supported on a slide plate
of the base. The slide plate is arcuately shaped to form a concavely arcuate arc
face on an opposite side of the distal end portion of the blade shoe, and the distal
end portion of the blade shoe has a convexly arcuate arc face corresponding to
the concavely arcuate arc face of the slide plate. The distal end portion of the
blade shoe is guided by a self-aligning action of the concavely arcuate arc face
of the slide plate in such a way that the distal end portion is centrally positioned
in a lateral direction on the slide plate. The guide member comprises a pair of
guide portions formed integrally on opposite side edges of the distal end portion
of the blade shoe, and hang below opposite side ends of the slide plate.
