Metal separator
A metal separator is applied to a fuel cell. A method of producing the metal separator involves performing a plate processing step of forming a bead base, and a rubber seal forming step of providing a rubber seal by screen printing for the bead base formed in the plate processing step. The rubber seal forming step includes a first protrusion forming step of forming a first protrusion at the central part in the width direction of a top portion of the bead base, in a cross sectional view taken along a thickness direction of the rubber seal, and a second protrusion forming step of forming a second protrusion configured to cover the first protrusion after the first protrusion forming step.
1. A metal separator to be applied to a fuel cell, the metal separator comprising:
a bead base protruding from a surface of the metal separator, and formed integrally with the metal separator; and
a rubber seal provided on the bead base,
wherein, in a cross sectional view taken along a thickness direction of the rubber seal, the rubber seal includes a first protrusion at a central part in a width direction of a top portion of the bead base, and a second protrusion provided outside the first protrusion and configured to cover the first protrusion,
wherein a protruding end surface of the second protrusion includes a depressed portion at a center in the width direction, and rising portions on both sides in the width direction,
and wherein a height difference between a lowest part of the depressed portion and a highest part of the rising portions is not more than 5% of a thickness of the rubber seal.
2. The metal separator according to claim 1 , wherein the first protrusion and the second protrusion have an identical modulus of elasticity.
3. The metal separator according to claim 1 , wherein the rubber seal is formed by screen printing, and a thickness of the rubber seal is set in a range of 50 μm to 150 μm.
4. A metal separator to be applied to a fuel cell, the metal separator comprising:
a bead base protruding from a surface of the metal separator, and formed integrally with the metal separator; and
a rubber seal provided on the bead base,
wherein, in a cross sectional view taken along a thickness direction of the rubber seal, the rubber seal includes a protrusion over a top portion of the bead base entirely in a width direction of the top portion,
a depressed portion is formed at an upper and widthwise central part of the protrusion, and
the rubber seal includes a filler portion configured to cover the depressed portion.
5. A metal separator to be applied to a fuel cell, the metal separator comprising:
a main separator body formed from a metal plate and including a flattened base portion;
a bead base protruding from the flattened base portion of the main separator body, and formed integrally therewith; and
a rubber seal provided on the bead base,
wherein, in a cross sectional view taken along a thickness direction of the rubber seal, the rubber seal includes a first protrusion at a central part in a width direction of a top portion of the bead base, and a second protrusion provided outside the first protrusion and configured to cover the first protrusion,
wherein a protruding end surface of the second protrusion includes a depressed portion at a center in the width direction, and rising portions on both sides in the width direction,
and wherein a height difference between a lowest part of the depressed portion and a highest part of the rising portions is not more than 5% of a thickness of the rubber seal.