A valve timing controller is provided with a first rotary element that
rotates in response to a crankshaft, a second rotary element that rotates
in response to a camshaft. Multiple link mechanisms are arranged
adjacently in the rotational direction of the first rotary element to
change a relative rotation phase between the first and second rotary
elements. The link mechanism in each group is constituted by combining
the first link linked to the first rotary element by a revolute pair with
the second link linked to the second rotary element and the first link.
The second link of the link mechanism in each group retains the first
link of each of the link mechanisms in the same group and the other group
in the rotational axis direction of the first rotary element between the
second link and the first rotary element.