Sealing element for a rotary timing system of internal-combustion engines.
A plurality of sealing elements (1) is accommodated in seats provided on the engine head and on a case which contains a rotary distribution cylinder. The sealing element is substantially composed of a widened head (2), the upper face (3) whereof is shaped complementarily to the surface of the distribution cylinder; a body (4) with a smaller cross section is connected to the head's lower face. The head and body of the sealing element have a quadrangular cross section and are arranged parallel to the distribution cylinder. The head and the body are axially traversed by at least two parallel holes (7,8) which connect the engine's combustion chamber and corresponding chambers of the distribution cylinder and connect these chambers to the induction and exhaust manifolds. The body of the sealing element is provided with perimetral grooves (5,6) for rings which constitute sliding seals on the seat in which the element is accommodated.