Patent ID: 8729413

Claim:
A push switch, comprising: a case having a bottom and an outer wall surrounding the bottom to form a recess portion; a first fixed contact placed on the bottom of the case; a second fixed contact placed on the bottom of the case; a dome-shaped movable contact placed in the recess portion and having a center portion facing the first fixed contact with a space therebetween; a protective sheet covering the recess portion; and a protrusion member fixed to the protective sheet at a convex side of the center portion of the movable contact, and placed between the protective sheet and the movable contact, the protrusion member and the protective sheet are melted together at an interface therebetween, wherein the first fixed contact and the second fixed contact are provided at positions where they are brought into contact with the movable contact when the movable contact is elastically reversed, wherein the protrusion member includes a top surface and a side surface, the side surface is not fixed to the protective sheet, a space is provided between the side surface and the protective sheet so that the space is capable of receiving air between the movable contact and an inner bottom face of the case when the movable contact is elastically reversed, wherein a periphery of the dome-shaped movable contact is in contact with the inner bottom face of the case before the movable contact is elastically reversed, so that the periphery of the dome-shaped movable contact is apart from the protective sheet at a distance of a height of the outer wall in the recess portion, and wherein a height of a top of the convex side of the center portion of the movable contact in the recess portion is substantially equal to the height of the outer wall in the recess portion, so that a) a portion of the protective sheet in contact with the protrusion member; and b) a portion of the protrusion member, project beyond the outer wall of the case.