Igniter assembly and molding method for holding part

An igniter assembly, comprising:

• an igniter including an accommodating space for accommodating an ignition charge for igniting a combustion agent;
• a collar for supporting the igniter;
• and
• a holding part formed of a resin material for fixing the igniter to the collar,
• wherein the igniter includes,
• a cup body provided with a peripheral wall having a cylindrical shape and a lid wall for closing one end of the peripheral wall, the cup body being provided such that the lid wall is positioned on a discharge direction side of a combustion product of the ignition charge when the igniter is activated a closing part disposed and thus closing an opening formed at an other end of the cup body, the closing part defining therein the accommodating space together with the cup body,
• the peripheral wall is sectioned, in an axial direction of the peripheral wall, into
• a contact region in contact with the closing part and
• a noncontact region being a region on a side of the lid wall relative to the contact region and not in contact with the closing part,
• wherein the holding part includes,
• a base part for fixing the igniter to the collar by covering a periphery of the contact region and
• a surrounding wall having an annular shape and formed continuously to the base part and configured to prevent the combustion agent from being disposed around the noncontact region by surrounding the noncontact region, and
• a fragile part is formed in the holding part between a first area including at least a part of the base part, and a second area, which is an area on a side of the discharge direction relative to the first area, the second area including a tip end of the surrounding wall, and thus the second area deforms radially outward preferentially compared with the first area when a load is applied to the surrounding wall by the igniter activated.